Cognitive Psychology - Midterm Reviewer.docx

**LESSON 1: INTRO TO COGNITIVE PSYCHOLOGY** **Cognitive psychology** is the study of how people perceive, learn, remember, and think about information. cognitive psychologist **might study how people perceive various shapes**, why they remember some facts but forget others, or how they learn langua...

**LESSON 1: INTRO TO COGNITIVE PSYCHOLOGY** **Cognitive psychology** is the study of how people perceive, learn, remember, and think about information. cognitive psychologist **might study how people perceive various shapes**, why they remember some facts but forget others, or how they learn language - **Heuristics** are mental shortcuts we use to process information. When we think about an issue and certain **examples immediately come to mind**, we are using the "availability heuristic" - **Dialectic** - A dialectic is a developmental process **whereby ideas evolve over time through a back-and-forth** exchange of ideas; in a way, it is like a discussion spread out over an extended period of time - **Thesis** - A thesis is a statement of belief - **Antithesis** - is a **statement that counters a thesis**. - **Synthesis** - integrates the most credible features of each of two (or more) views. **PHILOSOPHICAL ORIGINS OF PSYCHOLOGY** **RATIONALISM** - **Plato** - believes that the route to knowledge is through thinking and logical analysis. That is, a rationalist does not need any experiments to develop new knowledge. A rationalist who is interested in cognitive processes would appeal to **reason as a source of knowledge or justification** - **René Descartes** - Cogito, ergo sum (I think, therefore I am) - Viewed the introspective, reflective method as being superior to empirical methods for finding truth. - Only proof of his existence is that he was thinking and doubting. **EMPIRICISM** - **Aristotle** - believes that we acquire knowledge via empirical evidence--- that is, **we obtain evidence through experience and observation** - **John Locke** -- Tabula Rasa - Humans are born without knowledge and therefore must seek knowledge through empirical observation. **Immanuel Kant** - both rationalism and empiricism have their place **PSYCHOLOGICAL ORIGINS OF COGNITIVE PSYCHOLOGY** **STRUCTURALISM** - **1st major school of thought** in psychology. - Goal of Psychology: **seeks to understand the structure** (configuration of elements) of the mind and its perceptions by analyzing those perceptions into their constituent components (affection, attention, memory, and sensation) - Method: - **Introspection**- conscious observation of one's thinking processes. Introspection aims to look at the elementary components of an object or process. - **Proponent:** Wilhelm Wundt and Edward Titchener - Challenges of Introspection: - People may not always be able to say exactly what goes through their mind or may not be able to put it into adequate words. - **What they say may not be accurate**. - The fact that people are asked to **pay attention to their thoughts or to speak out loud** while they are working on a task may itself alter the processes that are going on **FUNCTIONALISM** - Goal of Psychology: seeks to understand what people do and why they do it particularly interested in the practical applications of their research. - Functionalists **were interested in how people learn**; they did not really specify a mechanism by which learning takes place - Method - Various method - introspection, observation, experiment - **Proponents:** William James, Principles of Psychology (1890) **PRAGMATISTS** - **Knowledge is validated by its usefulness**: - Goal of Psychology: concerned not only with knowing what people do; they also want to know what we can do with our knowledge of what people do. - **Proponent:** John Dewey **ASSOCIATIONISM** - Goal of psychology: examines how elements of the mind, such as events or ideas, can become associated with one another in the mind to result in a form of learning - **Contiguity** (associating things that **tend to occur together at about the same time**); - **Similarity** (associating things with **similar features or properties**) - **Contrast** (associating things that show polarities, such as hot/cold, light/dark, day/night). **Edward Lee Thorndike** - Law of Effect, Law of Satisfaction, Law of Readiness - Role of "satisfaction" is the key to forming associations. - A **stimulus will tend to produce a certain response over time** if an organism is rewarded for that response **BEHAVIORISM** - Goal of Psychology: focuses only on the relation between observable behavior and environmental events or stimuli - Considered an **extreme version of associations** focuses entirely on the association between the environment and an observable behavior. - **Method:** Animal experiments, conditioning experiments **Proponents of Behaviorism:** 1. **John Watson** - He believed that psychologists should concentrate only on the study of observable behavior. Behaviorism also differed from previous movements in psychology by shifting the emphasis of experimental research from human to animal participants 2. **Burrhus Frederic Skinner** - Believed that virtually all forms of human behavior, not just learning, could be explained by reactions to the environment. - **Rejected mental mechanisms** - Believed instead that **operant conditioning**---involving the strengthening or weakening of behavior, contingent on the presence or absence of reinforcement (rewards) or punishments---could explain all forms of human behavior. 3. **Ivan Pavlov** - Began with the observation that dogs salivated in response to the sight of the lab technician who fed them. This response occurred before the dogs even saw whether the technician had food. - CRITICISMS: - Behaviorism **did not account as well for complex mental activities**, such as language learning and problem-solving. - More than understanding people's behavior, some psychologists wanted to know what went on inside the head - Using the techniques of behaviorism **to study nonhuman animals was often easier than studying human ones.** Some psychologists rejected radical behaviorism. They were curious about the contents of the mysterious black box. - **Edward Tolman (1886--1959),** thought that understanding behavior required taking into account the purpose of, and the plan for, the behavior - **Bandura (1977)** noted that learning appears to result not merely from direct rewards for behavior, but it also can be social, **resulting from observations of the rewards or punishments** given to others **GESTALT PSYCHOLOGY** - Goal of psychology: to understand psychological phenomena as organized, **structured wholes**. The whole differs from the sum of its parts - Methods: Various methods -- experiment, observation - **Proponents:** Max Wertheimer, Wolfgang Köhler **EMERGENCE OF COGNITIVE PSYCHOLOGY** - In the early 1950s, a movement called the **"cognitive revolution"** took place in response to behaviorism. - Cognitivism is the belief that most human behavior explains how people think. **Karl Lashley (1890-1958)** - **Psychobiological arguments** against behaviorism - On a behaviorist, stimulus-response account, an activity such as rapidly playing a correct sequence of notes from memory on an instrument would involve an associative chain of stimuli and responses - **Such associative chains cannot explain the behavior**; input is never put into a a static system, but always into a system which is actively organized **Noam Chomsky** - **Linguistic arguments** against behaviorism - Arguments from language acquisition - Behaviorists cannot explain how children **can produce novel sentences they never heard** - Infinite number of sentences we **can produce cannot be learned by reinforcement** -- there must be a cognitive algorithmic structure in our mind underlying language **Alan Turing** - Development of first computers - His "Colossus" computer helped break the German "Enigma" codes during the World War II - It has been estimated that this work **shortened the war in Europe by two years** - Analogy between computers and human minds - **Hardware (brain), Software (mind).** Thinking can be described in terms of algorithmic manipulation of some information. These ideas gave rise to the **information processing paradigm in psychology** -- cognitive psychology **Artificial intelligence (AI)** is defined as human attempts to construct systems that show intelligence and, particularly, the intelligent processing of information. Many of the early cognitive psychologists became interested in cognitive psychology through applied problems. Advertising has extensively used applied cognitive psychology. **LESSON 2: RESEARCH METHODS IN COGNITIVE PSYCHOLOGY** **Cognitive psychology employs various research methods** - **Methods include:** - - Laboratory experiments - Neuroscientific research - Self-reports - Case studies - Naturalistic observation - Computer simulations and AI - Choice of method depends on research goals **Research Goals in Cognitive Psychology** - **Data gathering:** Collecting information about cognitive phenomena - **Data analysis:** Drawing inferences from collected data - **Theory development:** Creating explanatory frameworks - **Hypothesis formulation:** Generating testable predictions - **Hypothesis testing:** Evaluating predictions through research - **Application:** Translating findings to real-world settings **The Scientific Process in Cognitive Psychology** 1. 2. Develop a theory based on observations 3. Generate hypotheses from the theory 4. **Test hypotheses through experimentation** 5. Analyze results statistically 6. Retain or reject hypotheses 7. **Revise theory if necessary** 8. Apply findings to real-life situations when possible **Controlled Experiments: Key Concepts** - **Independent variables:** Manipulated by the experimenter - **Dependent variables:** Measured outcomes - **Control variables:** Held constant to prevent interference - **Confounding variables:** Uncontrolled factors that may affect results - **Random sampling:** Selecting participants representative of the population - **Random assignment:** Allocating participants to conditions **Common Dependent Variables in Cognitive Research** - Percent correct (accuracy) - Error rate - Reaction time (speed of processing) - These measures help researchers understand: - Accuracy of mental processing - Speed of mental processing **The Subtraction Method** - Used to **estimate time for specific cognitive processes** - **Process:** 1. Measure reaction time with the process of interest 2. Measure reaction time without the process 3. **Subtract the latter from the former** - Example: Estimating time to process a single word in a list **Correlational Studies** - Used when variables cannot be manipulated experimentally**. Measures relationship between two or more variables.** Expressed through Pearson\'s correlation coefficient (r) - **Ranges from -1.00 to +1.00** - Sign indicates **direction of relationship.** Magnitude indicates strength of relationship. Cannot establish causality **Neuroscientific Research Methods** 1. **Postmortem studies:** Examining brains after death 2. **In vivo imaging:** Studying brain structure/activity **in living individuals** 3. **Animal studies:** Investigating neural activity in animal models - Provides insights into brain-behavior relationships - Helps understand normal cognitive functions through abnormal cases - **Allows for procedures not ethical in human participants** **Self-Reports in Cognitive Research** - Participant\'s own account of cognitive processes - - Types: - **Retrospective accounts** - **Questionnaires and surveys** - Verbal protocols (think-aloud method) - Limitations: - Potential for inaccurate reporting - May alter cognitive processes being studied - Some processes occur outside conscious awareness **Case Studies and Naturalistic Observation** - **Case studies:** In-depth investigations of individuals - **Naturalistic observation:** Studying cognition in everyday contexts - - Advantages: - High ecological validity - Useful for rare conditions or events - Generate hypotheses and rich descriptions - Limitations: - Limited generalizability - Lack of experimental control **Computer Simulations and Artificial Intelligence** - **Computer simulations:** Programs **imitating human cognitive functions** - **Artificial Intelligence (AI):** Systems designed to perform cognitive tasks - Applications: - Modeling specific cognitive processes - Creating comprehensive cognitive architectures - Developing programs that mimic or surpass human performance - Example: Chess-playing programs (brute force vs. human simulation) **Cognitive Science: An Interdisciplinary Approach** - **Combines methods and ideas from:** - - Cognitive psychology - Cognitive neuroscience - Artificial Intelligence - Philosophy - Linguistics - Anthropology - - Focus: How humans acquire and use knowledge - Benefits from collaborations with various fields of psychology and related disciplines 1. **Fundamental Idea 1: Empirical Data and Theories** - Both are crucial in cognitive psychology - **Theories give meaning to data** - Data validate or refute theories - Iterative process: - Theory → Data collection → Theory refinement → Further data collection 2. **Fundamental Idea 2: Adaptive Nature of Cognition** - **Cognition is generally adaptive** - Allows accurate perception, learning, memory, reasoning, and problem-solving - However, cognitive processes can lead to systematic errors - Example: Overvaluing easily available information, even when less relevant 3. **Fundamental Idea 3: Interaction of Cognitive Processes** - Cognitive processes interact with each other - Example: Memory depends on perception - Cognitive processes interact with non-cognitive processes - Example: Motivation affects learning - Importance of studying processes in isolation and in interaction - Growing focus on cognitive-biological interactions (e.g., brain imaging studies) 4. **Fundamental Idea 4: Diverse Scientific Methods** - **No single \"right\" way to study cognition** - Multiple methods increase confidence in findings - Examples of methods: - Reaction time studies - Error rate analysis - Individual difference patterns - All methods must be scientific (allow for disconfirmation of hypotheses) 5. **Fundamental Idea 5: Basic and Applied Research** - **All basic research may lead to applications** - All applied research may lead to basic understandings - Distinction between basic and applied research often blurred - Example: - Basic finding: Spaced learning is superior to cramming - Immediate application: Improved study strategies - Applied research (e.g., eyewitness testimony) can enhance basic understanding of cognitive processes **Conclusion: The Goals of Cognitive Psychology** - Understand how people think in laboratories and everyday life - Identify underlying common ideas and organizing themes - Perceive meaningful patterns within cognitive psychology - Encourage deeper contemplation of cognitive problems - Bridge the gap between theoretical understanding and practical application **LESSON 3: COGNITION IN THE BRAIN: ANATOMY AND MECHANISMS** **INTRODUCTION TO THE NERVOUS SYSTEM** - The **nervous system** is the foundation of our ability to perceive, adapt to, and interact with the world - The **brain is the supreme organ of the nervous system** - **The cerebral cortex** controls many of our thought processes **MAJOR REGIONS OF THE BRAIN** 1. Forebrain 2. Midbrain 3. Hindbrain - These labels derive from the front-to-back arrangement in a developing embryo, not their final positions in an adult brain. **BRAIN DEVELOPMENT** - **Initial embryonic arrangement:** forebrain (front) →midbrain →hindbrain (back) - As the fetus develops, the orientation changes. The forebrain eventually forms a cap on top of the midbrain and hindbrain. **This process occurs from a few weeks after conception to birth** **THE FOREBRAIN: OVERVIEW** - The forebrain is **located at the top and front of the brain** and includes: - 1\. Cerebral - 2\. Basal ganglia - 3\. Limbic system - 4\. Thalamus - 5\. Hypothalamus **THE CEREBRAL CORTEX** - **Outer layer of the cerebral hemispheres** - Plays a vital role in thinking and other mental processes - Responsible for **higher-order cognitive functions** **BASAL GANGLIA** - **Collections of neurons crucial to motor function** - Dysfunction can result in motor deficits, including: - Tremors - Involuntary movements - Changes in posture and muscle tone - **Slowness of movement -** implicated in disorders like Parkinson\'s and Huntington\'s disease **THE LIMBIC SYSTEM: OVERVIEW** - **Important for emotion, motivation, memory, and learning** - More developed in mammals, especially humans - Allows for suppression of instinctive responses - **Helps adapt behaviors flexibly to changing environments**. Comprises three central interconnected structures: - Septum - Amygdala - Hippocampus **SEPTUM:** - Involved in **anger and fear** **AMYGDALA:** - Crucial for emotion, **especially anger and aggression** - Stimulation can result in fear responses - **Damage can lead to maladaptive lack of fear** - Enhances perception of emotional stimuli - Dysfunction linked to autism and social impairment **HIPPOCAMPUS:** - Essential for **memory formation** - Crucial for flexible learning and spatial memory - **Monitors spatial relationships** (\"what is where\") - Damage can result in inability to form new memories - Involved in declarative memory, but not procedural memory - Deterioration linked to Korsakoff\'s syndrome **THALAMUS:** - Relays incoming sensory information **to appropriate cortical regions**. Located approximately in the center of the brain - **Divided into nuclei** (groups of neurons with similar functions) - **Helps control sleep and waking** - Dysfunction can lead to various issues: - Pain, tremor, amnesia - Language impairment - Sleep-wake cycle disruptions - Abnormalities linked to schizophrenia symptoms **HYPOTHALAMUS:** - **Regulates behaviors related to species survival:** Fighting, feeding, fleeing, mating - Helps regulate emotions and stress reactions - Interacts with the limbic system - Controls many bodily functions despite its small size - Plays a role in sleep regulation (linked to narcolepsy) - Important for endocrine system functioning ▪ Stimulates the pituitary gland for hormone production **THE MIDBRAIN: OVERVIEW** - Helps control **eye movement and coordination** - Contains the **crucial Reticular Activating System (RAS)** - Part of the brainstem, connecting forebrain to spinal cord **RETICULAR ACTIVATING SYSTEM (RAS)** - Network of neurons essential for: - Regulating consciousness - Sleep and wakefulness - Arousal and attention - Vital functions (heartbeat, breathing): extends into the hindbrain, critical for conscious awareness and control **The hindbrain comprises three main structures:** 1. Medulla oblongata 2. Pons 3. Cerebellum - These structures are part of the brainstem and perform vital functions. **MEDULLA OBLONGATA:** - **Controls heart activity**, contains part of the Reticular Activating System (RAS) - **Largely controls breathing**, swallowing, and digestion. **Essential for keeping us alive**. - Point where nerves cross from one side of the body to the opposite side of the brain **PONS:** - **Contains neural fibers passing signals between brain parts** - Name means **\"bridge\" in Latin**, reflecting its function Contains a portion of the Reticular Activating System (RAS) - Houses nerves serving parts of the head and face **CEREBELLUM:** - **Controls bodily coordination**, balance, and muscle tone - Involved in some aspects of procedural memory - Name means \"little brain\" in Latin - Important for **motor learning and fine-tuning of movement** **BRAIN DEVELOPMENT AND EVOLUTION** - Prenatal brain development mirrors evolutionary development - **Hindbrain:** evolutionarily oldest, develops first prenatally - **Midbrain:** newer addition, develops second prenatally - **Forebrain:** most recent addition, develops last prenatally - Evolution has increased neural complexity, allowing for: - Enhanced voluntary control over behavior - Improved planning abilities - Better contemplation of alternative actions **CONCLUSION: THE BRAIN AND COGNITION** - The brain\'s complex structure underlies our cognitive abilities - Each region plays a crucial role in different aspects of cognition - Understanding brain anatomy helps explain cognitive processes - Continued research in neuroscience enhances our knowledge of brain-behavior relationships - This knowledge can lead to better treatments for neurological and psychiatric disorders **THE CEREBRAL CORTEX: STRUCTURE AND FUNCTION** - The cerebral cortex is a 1-3 mm layer wrapping the brain\'s surface. Crucial for human cognition: thinking, planning, perception, and language. Makes up 80% of the human brain ▪ Gray matter: contains neural cell bodies for information processing. Divided into left and right cerebral hemispheres **ANATOMY OF THE CEREBRAL CORTEX** - Convolutions increase surface area: - **Sulci:** small grooves - **Fissures:** large grooves - **Gyri:** **bulges** between grooves - If smoothed out, human cortex would cover about 2 square feet - Underlying white matter contains myelinated axons **HEMISPHERIC SPECIALIZATION** - Left and right hemispheres have different functions - **Contralateral organization:** each hemisphere controls opposite side of body - Some ipsilateral transmission occurs (e.g., olfactory information) - **Corpus callosum:** **neural fibers connecting hemispheres** **HISTORICAL DISCOVERIES IN HEMISPHERIC SPECIALIZATION** - **Marc Dax (1836):** Observed left hemisphere damage in aphasia patients - **Paul Broca (1861):** Identified Broca\'s area for speech production - **Carl Wernicke:** Discovered Wernicke\'s area for language comprehension - **Roger Sperry:** Nobel Prize winning research on hemispheric specialization **SPLIT-BRAIN RESEARCH** - Surgical severing of corpus callosum to treat epilepsy. Results in two separate specialized \"brains\". Reveals distinct functions of left and right hemispheres. Provides insights into language, spatial abilities, and information processing. **LEFT HEMISPHERE FUNCTIONS** - Language processing (90% of population) - Movement control and skilled actions - **Analytical thinking** and pattern recognition - Hypothesis generation - Grammatical and phonetic understanding **RIGHT HEMISPHERE FUNCTIONS** - Spatial visualization and orientation - Face recognition and self-recognition - Understanding context, metaphors, and humor - **Practical language use** - Holistic information processing **LOBES OF THE CEREBRAL CORTEX** - **Four main lobes:** 1. Frontal lobe 2. Parietal lobe 3. Temporal lobe 4. Occipital lobe - Each lobe has specialized functions but also interacts with others **FRONTAL LOBE:** - **Location:** Front of the brain - Functions: Motor processing - Higher thought processes (reasoning, problem-solving, planning) - Speech production - Contains prefrontal cortex and primary motor cortex 1. **PRIMARY MOTOR CORTEX** - Part of the frontal lobe responsible for planning, control, and execution of movement - **Contralateral organization** - **Mapped as a motor homunculus** - Body parts represented proportionally to their importance in motor control **PARIETAL LOBE:** - Location: Upper back portion of the brain Functions: - **Somatosensory processing** (touch, pressure, temperature, pain) - **Spatial perception** - Attention and consciousness - Contains primary somatosensory cortex 1. **SOMATOSENSORY CORTEX** - Part of the parietal lobe - Receives sensory information from the body - **Mapped as a sensory homunculus** - **Body parts represented proportionally** to their sensory importance **TEMPORAL LOBE:** - Location: Below the parietal lobe, near the temples - Functions: **Auditory processing** - **Language comprehension**, visual memory retention, object recognition **OCCIPITAL LOBE:** - Location: Back of the brain - Primary function: **Visual processing** - Contains multiple specialized visual areas for: color perception, motion detection, form recognition and spatial location **VISUAL CORTEX AND OPTIC CHIASMA:** - Visual cortex primarily located in the occipital lobe - **Optic chiasma:** crossover point for visual information - Contralateral and ipsilateral connections from eyes to visual cortex - Left visual field processed by right hemisphere, and vice versa **BRAIN ENERGY CONSUMPTION** - Brain makes up about 1/40 of body weight Uses approximately: 20% of circulating blood, 20% of available glucose, 20% of available oxygen **SUMMARY AND IMPLICATIONS** - **Cerebral cortex** is crucial for human cognition and behavior - Hemispheric specialization and lobe functions demonstrate complexity - Understanding brain structure and function is vital for cognitive psychology - Ongoing research in cognitive neuroscience continues to reveal new insights **NEURONAL STRUCTURE AND FUNCTION: THE BUILDING BLOCKS OF THE NERVOUS SYSTEM** **INTRODUCTION TO NEURONS** - **Neurons** are individual neural cells that transmit electrical signals in the nervous system - Highest concentration found in the neocortex of the brain - **Neocortex:** Part of the brain **associated with complex cognition** - Can contain up to **100,000 neurons per cubic millimeter** - Neurons form networks for information processing and feedback **BASIC STRUCTURE OF A NEURON:** 1. 2. **Soma (cell body)** - **Contains the nucleus of the cell** - Responsible for the life of the neuron - Performs metabolic and reproductive functions - Connects **dendrites to the axon** - **Integrates information received** from dendrites 3. **Dendrites** - **Branchlike structures** - Receive information from other neurons - Important for learning - Formation of **new neuronal connections** associated with learning 4. **Axon** - Long, thin tube extending from the soma - Responds to information by transmitting electrochemical signals - **Can split into branches** - Signals travel to the terminus (end) - **Two types:** myelinated and unmyelinated 5. **Terminal buttons** **MYELIN AND SIGNAL TRANSMISSION** - **Myelin:** white, fatty substance surrounding some axons - Myelinated axons transmit signals faster (up to 100 meters/second) - Myelin distributed in segments with gaps called **nodes of Ranvier** - Nodes of Ranvier **increase conduction speed** - Degeneration of myelin sheaths associated with multiple sclerosis **TERMINAL BUTTONS AND SYNAPSES** - **Terminal buttons:** **small knobs** at the ends of axon branches - **Synapse:** small gap between terminal buttons and dendrites of next neuron - **Synapses are crucial for cognition** - Rats show increased size and number of synapses after learning - Reduced synaptic efficiency linked to decreased cognitive function (e.g., Alzheimer\'s) **NEUROTRANSMISSION** - Signal transmission occurs when terminal buttons release neurotransmitters - Neurotransmitters: chemical messengers that cross the synaptic gap - Over 100 known neurotransmitter substances - Ongoing research on neurotransmitter interactions with drugs, moods, abilities, and perceptions **TYPES OF NEUROTRANSMITTERS: Three main types** - 1\. Monoamine neurotransmitters - 2\. Amino-acid neurotransmitters - 3\. Neuropeptides **ACETYLCHOLINE** - **Associated with memory functions** - Important for sleep and arousal - Loss of acetylcholine linked to impaired memory in **Alzheimer\'s patients** - Increase in cholinergic neuron activity upon awakening **DOPAMINE** - Associated with attention, learning, and movement coordination - Involved in **motivational processes** (reward and reinforcement) - High levels linked to schizophrenia (\"dopamine theory of schizophrenia\") - Low levels associated with Parkinson\'s disease - Dopamine treatment may increase pathological gambling behavior **SEROTONIN** - **Important role in eating behavior** and body-weight regulation - High levels associated with some types of anorexia (e.g., illness-induced) - **Involved in aggression and regulation of impulsivity** - Blocking serotonin may increase aggressive behavior **COMPLEXITY OF NEURONAL COMMUNICATION** - Constant neuronal communication is highly intricate - Complexities make it challenging to understand normal brain processes - Researchers study neurological and psychological disorders to gain insights - Example: Investigation of depression led to discoveries about mood regulating chemicals **NEUROTRANSMITTER IMBALANCES AND DISORDERS** - Chemical imbalances may contribute to various - Understanding imbalances can help develop treatments - Potential treatments: - Providing needed neurotransmitters - Inhibiting effects of overabundant neurotransmitters **PSYCHOPHARMACOLOGY AND THE BRAIN** - Brain receptors can be affected by psychoactive drugs (legal or illegal) - Drug molecules can occupy receptors normally used by endogenous neurotransmitters - This interaction forms the basis for many psychiatric medications and recreational drugs **NEUROPLASTICITY AND LEARNING** - Learning associated with formation of new neuronal connections - Synaptic changes occur during learning processes - Rats show increases in synapse size and number after learning tasks - Neuroplasticity: brain\'s ability to reorganize itself throughout life **NEURODEGENERATIVE DISEASES** - **Alzheimer\'s disease:** associated with loss of acetylcholine and reduced synaptic efficiency - **Multiple sclerosis:** caused by degeneration of myelin sheaths - P**arkinson\'s disease:** linked to low dopamine levels - Understanding these diseases helps illuminate normal brain function **NEUROTRANSMITTER IMBALANCES AND BEHAVIOR** 1. 2. **Serotonin:** - Low levels: Associated with **depression, anxiety**, and increased aggression - High levels: Can lead to **serotonin syndrome** (confusion, muscle rigidity, fever) 3. **Dopamine:** - Low levels: Linked to **Parkinson\'s disease** (movement problems), ADHD, and depression - High levels: Associated with **schizophrenia**, mania, and addictive behaviors 4. **Norepinephrine:** - Imbalance: Can contribute to **anxiety disorders**, depression, and ADHD - Low levels: May result in **lethargy** and lack of focus 5. **GABA (Gamma-aminobutyric acid):** - Low levels: Associated with **anxiety, epilepsy**, and insomnia - Imbalance: Can affect **mood and stress** response 6. **Glutamate:** - Excess levels: Linked to **neurodegenerative diseases** like Alzheimer\'s and ALS - Imbalance: Can contribute to **cognitive impairments** and mood disorders 7. **Acetylcholine:** - Low levels: Associated with **memory problems** and cognitive decline in Alzheimer\'s disease - Imbalance: Can affect **attention** and learning abilities **CURRENT RESEARCH IN NEUROSCIENCE** - Ongoing investigations into neurotransmitter functions and interactions - Studies on the relationship between brain chemistry and psychological states - Development of new treatments for neurological and psychiatric disorders - Exploration of brain-computer interfaces and neural engineering **CONCLUSION: THE FUTURE OF NEUROSCIENCE** - **Rapid advancements in neuroimaging** and molecular biology - Potential for personalized treatments based on individual brain chemistry - Ethical considerations in neuroscience research and applications - Continued exploration of the complex relationship between brain structure, function, and behavior **EXPLORING BRAIN STRUCTURE AND FUNCTION: METHODS IN NEUROSCIENCE** **INTRODUCTION TO BRAIN RESEARCH** - Brain research uses various methods to understand structure and function - **Two main categories:** postmortem studies and in vivo techniques - **Earlier focus:** studying brains after death - **Current trend: observing** mental functioning in real-time - Each method provides unique insights into brain structure and function **POSTMORTEM STUDIES** - Definition: Examination of the brain after death - Process: - Observe and document behavior of living patients with brain damage - Examine patients\' brains for lesions after death - Infer relationships between lesioned areas and affected behaviors - Example: Phineas Gage case study (19th century) - Limitations: Cannot observe active physiological processes **CASE STUDY: BROCA\'S PATIENT** - Patient nicknamed \"Tan\" due to speech impairment - Showed severe speech production problems - Postmortem examination revealed lesions in the frontal lobe - Led to identification of Broca\'s area - **Broca\'s area:** region involved in speech production - Demonstrates link between brain structure and specific functions **STUDYING LIVE NONHUMAN ANIMALS** - Allows observation of physiological processes in living brains - Three main approaches: - Single-cell recordings ▪ - Selective lesioning - **Genetic knockout procedures** - Provides insights not possible with human subjects - Limitations: Generalization to humans may be restricted **SINGLE-CELL RECORDINGS** - Process: Insert thin electrode next to a single neuron in an animal\'s brain - Purpose: Record changes in electrical activity when exposed to stimuli - Application: Study of visual perception (e.g., Hubel & Wiesel\'s Nobel Prize-winning research) - Limitation: Not safe for use in humans **SELECTIVE LESIONING AND GENETIC KNOCKOUTS** 1. **Selective Lesioning:** - Surgically remove or damage part of the brain - Observe resulting functional deficits 2. **Genetic Knockouts:** - Some drugs can induce reversible lesions - Use genetic manipulation to create animals lacking certain brain cells or receptors - Compare with normal animals to infer function of missing components **STUDYING LIVE HUMANS: OVERVIEW** - Less invasive techniques used for ethical reasons. Three main categories: - Electrical recordings - Static imaging - Metabolic imaging - Each provides unique insights into brain structure and function **ELECTRICAL RECORDINGS: EEG AND ERP** 1. 2. **Electroencephalogram (EEG):** - Records electrical frequencies and intensities of the living brain - Electrodes placed on scalp - Used to study sleep states, epilepsy, etc. 3. **Event-Related Potential (ERP):** - Measures small changes in brain\'s electrical activity **in response to specific stimuli** - Provides good temporal resolution - Used to study attention, language processing, cognitive development **STATIC IMAGING TECHNIQUES** 1. 2. **Computed Tomography (CT) Scan:** - Uses X-rays to create 3D images of the brain - Detects large abnormalities (e.g., tumors, stroke damage) 3. **Angiography:** - Examines blood flow in the brain - Useful for detecting strokes, aneurysms, arteriosclerosis 4. **Magnetic Resonance Imaging (MRI):** - Uses magnetic fields to create high-resolution images - Two types: structural MRI and functional MRI (fMRI) **METABOLIC IMAGING: BASIC PRINCIPLES** - Relies on changes in brain\'s consumption of glucose and oxygen ▪ Active areas consume more glucose and oxygen - Subtraction method: - Compare activity during task of interest vs. control task - Difference indicates areas specifically involved in target task - Limitation: Cannot determine if activity is excitatory or inhibitory **POSITRON EMISSION TOMOGRAPHY (PET)** - Measures increases in **oxygen consumption** in active brain areas - Process: - Participant given mildly radioactive form of oxygen - Brain scanned to detect positrons emitted during metabolism - Computer analyzes data to produce images of brain function - Applications: Diagnosis of cognitive disorders, studying brain efficiency in intelligence **FUNCTIONAL MAGNETIC RESONANCE IMAGING (FMRI)** - Uses **magnetic fields to construct 3D representation of brain activity** - Based on increases in oxygen consumption ▪ Higher temporal resolution than PET - Process: - Participant performs task inside MRI machine - More active areas draw more oxygenated blood - Computer analyzes data to provide precise information on brain activity - Applications: Studying vision, attention, language, memory **DIFFUSION TENSOR IMAGING (DTI)** - **Examines restricted dispersion of water in brain tissue,** especially axons - Useful for: Mapping white matter in the brain, examining neural circuits - Applications: Studying traumatic brain injury, schizophrenia, brain maturation, multiple sclerosis **TRANSCRANIAL MAGNETIC STIMULATION (TMS)** - **Temporarily disrupts normal brain activity in a limited area** - Process: Electrical current passed through coil on head generates magnetic field - Advantages: Can imitate lesions or stimulate brain regions, allows examination of causal relationships - Applications: Investigating brain areas involved in motor actions, potential treatment for neuropsychological disorders **MAGNETOENCEPHALOGRAPHY (MEG)** - Measures brain activity by **detecting magnetic fields** from outside the head - Allows localization of brain signals with high precision - Applications: - Helping surgeons locate pathological structures - Studying phantom limb pain - Advantage: One of the most precise measuring methods **EMERGING TECHNIQUES** - Combination of fMRI and MEG: Integrates spatial (fMRI) and temporal (MEG) information - Provides more detailed understanding of brain processes - **Functional Transcranial Doppler Sonography (fTCD):** **Uses ultrasound to track blood flow velocity in the brain**, continuous monitoring with high temporal resolution, suitable for children or less cooperative subjects **NEAR-INFRARED SPECTROSCOPY (NIRS)** - Monitors blood flow and oxygen levels in the prefrontal cortex - Process: Sensor attached to forehead takes measurements before, during, and after tasks - Advantages: Relatively easy to use, allows some subject movement, portable for various settings - Particularly useful for studies involving children **LIMITATIONS AND CONSIDERATIONS** - Current techniques do not provide unambiguous mappings of functions to brain structures - Relationships between cognitive functions and brain structures are often inferred - Multiple brain structures may influence particular functions - Best results often come from combining multiple techniques - Some studies combine in vivo animal studies with brain imaging techniques **FUTURE DIRECTIONS IN BRAIN RESEARCH** - Continued development of non-invasive techniques - Improved spatial and temporal resolution in imaging - Integration of multiple imaging modalities - Advancements in data analysis and interpretation - Increased focus on individual differences and personalized medicine - Potential for new insights into neurological and psychiatric disorders - Ethical considerations in brain research and potential applications **NEUROSCIENCE TECHNIQUES IN RESEARCH** EEG APPLICATIONS IN RESEARCH - **Sleep Studies:** ▪ Monitoring sleep stages and disorders - Example: Using EEG to diagnose narcolepsy by observing abnormal sleep patterns - **Cognitive Development:** Tracking brain maturation in children - Example: Studying language acquisition in infants by measuring - ERP responses to native vs. non-native phonemes - **Neurofeedback:** Training individuals to control their brain activity - Example: Using EEG neurofeedback to help individuals with ADHD improve attention **FMRI IN COGNITIVE NEUROSCIENCE** - Decision Making: Observing brain activity during complex choices - Example: Studying neural correlates of moral decision-making by presenting ethical dilemmas in the scanner - Memory Formation: Tracking brain activity during encoding and retrieval - Example: Investigating how emotional content affects memory formation by comparing brain activity for emotional vs. neutral stimuli - Neuroplasticity: ▪ Examining brain changes due to learning or injury - Example: Monitoring brain reorganization in stroke patients during rehabilitation **PET SCANS IN CLINICAL RESEARCH** - Alzheimer\'s Disease: ▪ Detecting early signs of neurodegeneration - Example: Using PET to image amyloid plaques in the brain, a hallmark of Alzheimer\'s - Cancer Research: Monitoring tumor metabolism and treatment response - Example: Tracking glucose uptake in brain tumors before and after chemotherapy - Parkinson\'s Disease: Assessing dopamine function - Example: Using PET to measure dopamine receptor density in patients with early-stage Parkinson\'s **TMS IN COGNITIVE ENHANCEMENT AND THERAPY** - Depression Treatment: Stimulating brain regions to alleviate symptoms - Example: Using repetitive TMS on the dorsolateral prefrontal cortex to treat major depressive disorder - Stroke Rehabilitation: Enhancing motor recovery - Example: Applying TMS to the motor cortex to improve hand function in stroke survivors - Cognitive Enhancement: Temporarily boosting cognitive abilities - Example: Using TMS to enhance creative problem-solving by suppressing specific brain regions **BRAIN DISORDERS: UNDERSTANDING COGNITIVE IMPAIRMENTS** - Brain disorders can significantly impair cognitive functioning - They provide valuable insights into brain function - Historical approach: Detailed patient observations and post-mortem analysis - Modern approach: In vivo techniques for diagnosis and research - **Focus on three major categories: Stroke, Brain Tumors, and Head Injuries** **STROKE: OVERVIEW** - **Definition:** Sudden **disruption of blood flow** to the brain - Results in marked loss of cognitive functioning - Symptoms depend on the affected brain area - Can cause paralysis, speech loss, language comprehension issues, and impaired thought processes 1. 2. **Ischemic Stroke:** - Caused by **buildup of fatty tissue in blood vessels** - Piece of tissue breaks off and lodges in brain arteries - Treatable with clot-busting drugs 3. **Hemorrhagic Stroke:** - Occurs when a blood vessel in the brain **suddenly breaks** - Blood spills into surrounding tissue, causing cell death **SYMPTOMS:** - Numbness or weakness (especially on one side of the body) - Confusion and difficulty speaking or understanding speech - Vision disturbances Dizziness, trouble walking, or loss of balance - Severe headache with no known cause **BRAIN TUMORS:** - **Also called neoplasms** - Can seriously affect cognitive functioning - Occur in gray or white matter (more common in white matter) - **Two main types: Primary (originate in brain) and Secondary (spread from elsewhere)** 1. 2. **Benign Tumors:** - Do not contain cancer cells - Usually removable and don\'t grow back - Can still be dangerous if pressing on sensitive brain areas 3. **Malignant Tumors:** - Contain cancer cells - Grow quickly and invade surrounding healthy tissue - Life-threatening **BRAIN TUMOR SYMPTOMS** - - Headaches (often worse in the morning) - Nausea or vomiting - Changes in speech, vision, or hearing - Balance or walking problems - Mood, personality, or concentration changes - Memory issues - Seizures or muscle twitching - Numbness or tingling in extremities **BRAIN TUMOR DIAGNOSIS AND TREATMENT** - - Diagnosis methods: - Neurological examination - CT scan - MRI - Common treatment approach: Combination of surgery, radiation, and chemotherapy **HEAD INJURIES:** - Result from various causes (e.g., car accidents, hard object impacts, bullet wounds) - Surprisingly common: 1.4 million North Americans affected annually \\(\~50,000\\) deaths and \\(235,000\\) hospitalizations per year - \\(2\\)% of U.S. population needs long-term assistance due to head injuries 1. 2. **Closed-head injuries:** - Skull remains intact - Brain damage from mechanical force - Example: Hitting head on windshield in car accident 3. **Open-head injuries:** - Skull is penetrated - Example: Bullet wound **IMMEDIATE SYMPTOMS OF HEAD INJURY** - - Abnormal breathing - Speech or vision disturbances - Pupils of unequal size - Weakness or paralysis - Dizziness - Neck pain or stiffness **COGNITIVE SYMPTOMS OF HEAD INJURY** - - Concentration problems - Difficulty understanding others - Trouble expressing thoughts verbally - Challenges with abstract concepts - Memory issues **CASE STUDY: KEVIN PEARCE** - Snowboarder who suffered traumatic brain injury before 2010 Olympics - Spent a month in intensive care - Required 3 months of hospital rehabilitation - Had to relearn basic skills like walking and speaking - Recovery continued for years post-accident - Now advocates for brain injury awareness and support **IMPACT OF BRAIN DISORDERS ON COGNITIVE FUNCTION** - Affects various cognitive domains: Memory, Attention, Language, Executive functions, Perception - Severity and specific impairments depend on the type and location of the disorder **NEUROPLASTICITY AND RECOVERY** - Brain\'s ability to reorganize and form new neural connections - Crucial for recovery from brain disorders - Rehabilitation techniques often leverage neuroplasticity - Can lead to significant improvements in cognitive function over time **DIAGNOSTIC TECHNIQUES FOR BRAIN DISORDERS** - Neurological examination - Neuroimaging: CT, MRI, fMRI, PET - Electroencephalography (EEG) - Neuropsychological testing - Blood tests and cerebrospinal fluid analysis **TREATMENT APPROACHES** - Medication (e.g., anticoagulants for stroke, chemotherapy for tumors), Surgery (tumor removal, relieving pressure in head injuries), Radiation therapy, Cognitive rehabilitation, Physical and occupational therapy, Speech and language therapy PREVENTION AND RISK REDUCTION - Maintain a healthy lifestyle (diet, exercise, no smoking), Control blood pressure and cholesterol, wear protective gear during high-risk activities, Regular medical check-ups, Recognize and respond quickly to warning signs FUTURE DIRECTIONS IN BRAIN DISORDER RESEARCH - Advanced neuroimaging techniques - Gene therapy and targeted drug delivery - Brain-computer interfaces for rehabilitation - Stem cell therapies for brain repair - Artificial intelligence in diagnosis and treatment planning **CONCLUSION** - Brain disorders significantly impact cognitive function and quality of life - Understanding these disorders provides crucial insights into brain function - Ongoing research and technological advancements offer hope for improved diagnosis, treatment, and prevention - Importance of public awareness and support for those affected by brain disorders **LESSON 4: VISUAL PERCEPTION** **Our Visual System** - **Electromagnetic light energy** is converted into neural electrochemical impulses 1. **Light reflected from a surface** enters the eyes via the transparent cornea, bending to **pass through the pupil** at the center of the colored iris. 2. Behind the iris, **the thickness and shape of the lens adjust to focus light on the retina**, where the image appears upside down and backward. **Vision is clearest at the fovea**. 3. Light-sensitive receptor cells in the retinal surface, excited or inhibited by spots of light, influence the specialized neurons that signal the brain's visual centers through their bundled axons, which make up the optic nerve. The **optic nerve creates the blind spot**. - Light bounces off an object in the world - Projected onto the retina - The retina transduces the light (turns it into neurons firing) **THREE MAIN LAYERS OF RETINA:** - **Ganglion** cells - **Amacrine** cells (horizontal cells, bipolar cells) - **Photoreceptors** (rods and cones) **VISUAL PATHWAYS IN THE BRAIN:** - "what" -- Temporal lobe lesions in monkeys (can indicate where but not what) - "where" -- Parietal lobe lesions in monkeys (can indicate what but not where) From eye to back of the brain **(Occipital lobe)** where visual info is processed - **Contralateral** (based on visual field) - The wiring from the retina to the occipital lobe of the brain is quite orderly - **Electromagnetic radiation** (light waves) hit the eye. Neural firing (action potentials) go from eye to brain. **VISUAL PERCEPTION** - **Perception:** the process of recognizing, organizing and interpreting sense information - What we see (visual perception) is not exactly what's out there in the world 1. **DISTAL OBJECT** - (distal -- distance, i.e. out there) 2. **INFORMATIONAL MEDIUM** - Light reflected off his face - (atmosphere, time of day) 3. **PROXIMAL STATUS** - (in proximity) - **Light absorbed by retina in the eye** - (projected onto 2D surface) 4. **PERCEPTUAL OBJECT** - What we **actually experience seeing** - Day vs. Clay = context and past experience/knowledge matters, i.e. "top-down effects on perception" - Sometimes we fail to perceive what does exist - Sometimes we perceive things that do not exist - What we perceive is not identical to the distal object out there - What we perceive is not the proximal stimulus. Our brain **uses cues and context to interpret the proximal stimulus that hits the retina** **PERCEPTUAL BASICS:** - **Sensory adaptation** -- occurs when sensory receptors change their sensitivity to the stimulus - Our **senses respond to change -- Ganzfeld effect** 1. **Perceptual Constancy** - Object remains the same even though our sensation of the object changes. - Size constancy vs shape constancy - Each person\'s experience creates perceptual constancy - constancies of size, colour, shape, and brightness 1. **Size Constancy** - the tendency to **perceive an object as being on one siz**e no matter how far away the object is 2. **Color Constancy** - the tendency to **perceive objects as keeping their color** even though different light might change the appearance of their color 3. **Shape Constancy** -- the tendency to **perceive the same shape in an object** no matter what angle you view it from 4. **Brightness Constancy** -- the tendency to **perceive an object as being equally bright** even when the intensity of the light around it changes **THEORIES OF PERCEPTION:** - Bottom-up vs top-down theories - Bottom-Up processing theories - Direct perception - Template theories - Feature-matching theories - Recognition-by-components theory 1. **GIBSON'S THEORY OF DIRECT PERCEPTION** - The information in our sensory receptors is all we need - **No complex through process** (ex: use texture gradients as cues for depth and distance, mirror neurons start firing 30-100ms after a visual stimulus) 2. **TEMPLATE THEORIES** - Compare to templates ion memory until a match is found - **Problem of imperfect matches** (cartoony versions of animals) 3. **FEATURE-MATCHING THEORIES** - Recognize objects by feature - Detect elements and assemble them **into more complex forms**. Brain cells respond to specific features (lines and angles) - **Hubel & Wiesel (1979)** -- each neuron only responded to a very specific situation in a very specific place in the visual field - **Simple cells:** bars/edges - **Complex cells:** respond to moving edges, bars/edges detect bars of particular orientation - **Hypercomplex cells:** moving edges of a particular orientation and length, particular colors (simple and complex cells), moving in a particular direction - **Pandemonium Model (Four kinds of demons)** - Image, feature, cognitive, decision demons 4. **RECOGNITION BY COMPONENTS THEORY** - Breaks **objects down into "geons"** (for geometric ions) **Sensation does not equal perception** **TOP-DOWN INFLUENCES:** - When reading sentences, "bottom-up" would be seeing the lines/curves that make up each letter, **forming each letter into a word**, forming words into sentences, and so on - Bottom-up theories have trouble accounting for the fact that we can understand jumble of letters (order of letters inside of a word) - Top-down influences on perception - **The Likelihood Principle:** we perceive the world in the way that is "most likely" based on our past experiences - Perception is not automatic from raw stimuli (making inferences, guessing from experience) - **Word Superiority Effect:** better recognition of letters presented within words compared to isolated letters or letters in non-words - **Configural Superiority Effect:** objects presented in context are easier to recognize **than** **objects presented alone** **GESTALT'S VIEW OF PERCEPTION** - The whole is more than a sum of its parts - **Law of Prägnanz** -- individuals organize their experience in as simple, concise, symmetrical, and complete manner as possible - These principles allow us to make sense of what we see 1. **Closure:** the tendency to perceive a complete or whole figure even when there is something missing; there are gaps in what our senses tell us 2. **Figure-Ground perception:** the perception of figures against a background; **what you see depends on which you are looking at** and it can change as your eyes move from one area to another 3. **Proximity:** the perceptual tendency to group together visual and auditory events that are near each other; we group things together because they are close to each other 4. **Similarity:** the perceptual tendency to group things together because they are alike 5. **Continuity:** the perceptual tendency to group stimuli into continuous patterns **(following the smoothest path)** 6. **Common Fate:** the tendency to perceive objects that are moving together as belonging together 7. **Law of Good Form:** the tendency to organize forms in simplest way possible 8. **Relative size:** objects farther away appear to be smaller while objects that are larger appear to be closer 9. **Height in plain**: distant objects in a picture appear higher while closer objects are lower in the visual field **MOVEMENT:** 1. **Phi Phenomenon:** mistaking **apparent movement** for the real thing 2. **Stroboscopic Motion:** the **illusion of movement** produced by the rapid progression of images or objects that are not moving at all; example -- movies **DEPTH PERCEPTION** - This allows us to **develop the ability to judge depth or distance away of objects**. We perceive this distance **by using monocular and binocular cues** - There is evidence that depth perception begins to develop early in life. - The Visual Cliff experiment showed this, the very young infants seemed to be unafraid when placed on the Cliff at the edge of the apparent drop-off. - By nine months, infants responded with the fear to the drop off. Other studies showed that they wouldn\'t even cross the "cliff" when called by their mothers. Crawling apparently signaled the need to sense this danger. - The only animal that would regularly cross the "cliff" **was a rat**. This was because they don\'t use their vision to sense danger. Their whiskers told them that the surface was still solid, so they moved across it. **MONOCULAR CUES** - There are several of these which allows us to judge how close or far away objects are 1. **Linear perspective:** the tendency to see parallel lines as coming closer together, or converging, as they move away from us 2. **Interposition (overlap, relative position):** the tendency to perceive an object as being closer if it blocks another object 3. **Shadows and highlights:** objects with highlights on their surface and shadows beneath appear to be closer 4. **Texture Gradient:** the **more texture or detail** we see in an object, the **closer** we perceive it to be 5. **Motion Parallax:** The tendency of objects to seem to move forward or backward depending on how far away they are from the viewer; An example is looking at nearby things out the car window versus objects farther away. 6. **Atmospheric Perspective:** The tendency to **perceive hazy or smoky objects** as farther away. **BINOCULAR CUES:** - Both eyes are needed to perceive these cues. 1. **Retinal Disparity:** Binocular cue for perceiving depth based on the difference **between 2 images of an object that the retina receives**. As the object moves closer; As the object gets closer, the disparity gets greater. 2. **Convergence:** Movement of eye muscles that cause pupils to come closer together as an object is brought closer. **OPTICAL ILLUSIONS:** - This is a false visual perception of a stimulus. These are **not hallucinations** where there is no external stimulus. **They exist; we just see them inaccurately.** **FUSIFORM GYRUS IN TEMPORAL LOBE:** - Pattern recognition, facial recognition, high expertise in any item (birds, cars) recognition - Expert individuation hypothesis **EVIDENCE FOR SEPARATE SYSTEMS:** 1. **Prosopagnosia** - Inability to recognize faces after brain damage - Ability to recognize objects is intact 2. **Associative Agnosia** - Difficulty with recognizing objects - Can recognize faces **DEFICITS IN PERCEPTION** - Disruption of the "how" pathway -- **OPTIC ATAXIA** -- cannot use vision to guide movement, unable to reach for items - Disruption of the "what" pathway -- **AGNOSIA** -- inability to recognize and identify objects or people - **Simultagnosic** -- normal visual fields, yet act blind; perceives only one stimulus at a time -- single word or object - **Prosopagnosia** -- inability to recognize faces, including one's own **LESSON 5: ATTENTION AND CONSCIOUSNESS** **ATTENTION** - Attention is the **means by which we actively process a limited amount** of information. **CONSCIOUSNESS** - Consciousness includes **both the feeling of awareness and the content of awareness**, some of which may be under the focus of attention (Bourguignon, 2000; Farthing, 1992, 2000; Taylor, 2002) 1. It **helps monitor our interactions** with the environment 2. It assists us in **linking our past memories and our present** (sensations) to give us a sense of continuity of experience. 3. It helps us **control and plan for our future actions** based on the information from monitoring and from the links between past memories and present sensations **Main Functions of Attention** 1. Signal detection and vigilance 2. Search 3. Selective attention 4. Divided attention **Signal Detection Theory (SDT)** - Measure **sensitivity to a target's presence** **Vigilance and SDT** - Vigilance is **attending to a set of stimuli over a length of time** in order to detect a target signal - Vigilance decreases rapidly over time (fatigue), thus misses and false alarms increase **Search** - **Actively searching for a target** - **Number of targets** and distracters influence accuracy - Feature search versus conjunctive search - **Conjunctive Search** - Find the letter T -- Which panel is easier? (same characteristics) - **Feature Search** - Find the letter O -- Easier or harder than the previous one? (different characteristics) **Feature-Integration Theory (FIT)** - Individual feature processing is done in parallel -- **Simultaneous processing is done on the whole display** and if feature is present, we detect it - **Conjunctive searching** requires attention to the integration or combination of the features -- **Attention to particular combination of features** must be done sequentially to detect presence of a certain combination **Another Feature Search (colors instead of characteristics)** - Is there a red T in the display? Target is defined by a single feature - According to feature integration theory, **the target should "pop out"** - No attention required **Another Conjunction Search** - Is there a red T in the display? - Target is defined by **two features: shape and color** - According to FIT, the features must be combined and so attention is required - **Need to examine one by one** **Similarity Theory** - Similarity between targets and distracters is important, not number of features to be combined - **More shared features** = more difficult to detect a target **Guided Search (Cave & Wolf 1990)** - All searchers have two phases - Parallel phase (simultaneous) - Serial phase (one at a time) **Selectivity of Attention** - **Cocktail party phenomenon** - Cherry's Shadowing Technique - **Attended ear and unattended ear** (listening to two different conversations and repeat one of the messages; may be binaural or dichotic) - **Noticed in unattended ear** -- change in gender, change to a tone - **Did not notice in unattended ear** -- changed language, changed topic, same speaker; if speech was played backwards **MODELS OF SELECTIVE ATTENTION** 1. **Broadbent's model --** we **filter information** **right after we notice it at the sensory level** - Had trouble explaining: - Why participant's name gets through; why participants shadow meaningful message that switches from one ear to another; effects of practice on detecting information in unattended ear (e.g., detect digit in unattended ear for naïve and practiced participants) 2. **Selective Filter Model** - Moray (1959) found that even when participants ignore most other high-level (e.g., semantic) Selective Filter Model aspects of an unattended message, **they frequently still recognize their names in an unattended ea**r (Wood & Cowan, 1995). - Moray suggested that the reason for this effect is that **messages that are of high importance to a person may break through the filter** of selective attention (e.g., Koivisto & Revonsuo, 2007; Marsh et al., 2007). But other messages may not. - According to Moray, the filter blocks out most information at the sensory level. **But some personally important messages are so powerful** that they burst through the filtering mechanism. 3. **Treisman's Attenuation Model** - Instead of blocking stimuli out, **the filter weakens the strength of stimuli** other than the target stimulus  4. **Late Selection Theory** - **All stimuli is processed to the level of meaning**; relevance determines further processing and action A diagram of a process Description automatically generated 5. **Neisser's Synthesis** - **Preattentive processes** (parallel, note physical characteristics) - **Attentive processes** (controlled processes occur serially, occur in working memory) **DIVIDED ATTENTION** - How many tasks can you do at once? - **Dual-task paradigm** - The researchers would compare and contrast the response time (latency) and accuracy of performance in each of the three conditions. - Of course, **higher latencies mean slower responses**. As expected, initial performance was poor for the two tasks when the tasks had to be performed at the same time. Dual-task paradigm - Spelke, Hirst, and Neisser, however, had their participants practice to perform these two tasks five days a week for many weeks (85 sessions in all). To the surprise of many, given enough practice, the participants' performance improved on both tasks. They showed improvements in their speed of reading and accuracy of reading comprehension, as measured by comprehension tests. They also showed increases in their recognition memory for words they had written during dictation. Eventually, participants' performance on both tasks reached the same levels that the participants previously had shown for each task alone **CAPACITY MODELS OF ATTENTION** Real-life dual task - **Driving and cellphones; adjusting to music; watching the scenery** - Almost 80% of crashes and 65% of near-crashes involved some form of driver inattention within three seconds of the event - Strayer and Drews (2007) -- naturalistic observation of phone use and driver behavior - Conclusion: impact of hands-free cell-phone conversations on simulated driving -- cell-phone conversations led to inattentional blindness; even if they looked at an object, participant did not remember the object **FACTORS THAT INFLUENCE OUR ABILITY TO PAY ATTENTION** 1. Anxiety 2. Arousal 3. Task difficulty 4. Skills **THREE SUBFUNCTIONS OF ATTENTION** 1. **Alerting** - **Being prepared to attend to some incoming event** and maintaining this attention - Involves right frontal and parietal cortexes as well as the locus coeruleus 2. **Orienting** - The **selection of stimuli to attend to**; needed when we perform a visual search; involves the superior parietal lobe, the temporal parietal junction, the frontal eye fields, and the superior colliculus 3. **Executive attention** - Processes for **monitoring and resolving conflicts** that arise among internal processes; involves the anterior cingulate, lateral ventral, and prefrontal cortex as well as the basal ganglia **When attention fails us:** ADHD; change blindness and inattentional blindness; spatial neglect 1. **Attention Deficit Hyperactivity Disorder (ADHD)** - Symptoms: inattention, hyperactivity, impulsivity; not everyone who is overly hyperactive, inattentive, or impulsive has ADHD - Behavior must be demonstrated to a degree that is inappropriate for the person's age 2. **Change blindness** - An **inability to detect changes in objects** or scenes that are being viewed - **Inattentional blindness:** people are not able to see things that are actually there 3. **Spatial neglect** - **Lesion on one side of brain** causes person to ignore half of their visual field **HABITUATION** - **Decrease in responsiveness** when **exposed to a repeated stimulus** - People who smoke do not notice the smell of cigarettes on their clothes, but nonsmokers do; people get used to hearing the chiming of their clocks **DISHABITUATION** - Change in familiar stimuli **causes one to notice it again** - Smokers who quit suddenly notice how much their clothes smell of smoke; if clock breaks, owner suddenly notices the clock isn't chiming **HAIBUATION/DISHABITUATION PARADIGM** - Allows psychologists to test abilities of infants and animals; measure subject's arousal to see if a change occurs when pattern or sound changes - If animal or infant dishabituates to a change, they can detect the change; if the animal or infant does not dishabituate to a change in stimuli, they do not detect the change **CONTROLLED VS AUTOMATIC PROCESSING** 1. **Automatic processing** -- requires no conscious control 2. **Controlled processing** -- requires conscious control **AUTOMIZATION: TWO EXPLANATIONS** 1. **Integrated components theory (Anderson)** - Practice leads to integration; less and less attention is needed 2. **Instance theory (Logan)** - Retrieve from memory specific answers, skipping the procedure; **thus less attention is needed** **EFFECTS OF PRACTICE ON AUTOMATIZATION** - **Negative-acceleration curve** -- rate of learning slows as amount of learning increases **STROOP EFFECT** - Say the color of the words are printed in as quickly as you can - **Reading interferes with your ability to state the color**, and your reaction time is slower **CONSCIOUSNESS** - The Consciousness of Mental Processes - People have good conscious access to their complex information processes. - Second view is that people's access to their complex mental processes is not very good (e.g., Nisbett & Wilson, 1977). In this view, people may think they know how they solve complex problems, but their thoughts are frequently erroneous **Preconscious processing** - Information that is available for cognitive processing but that **currently lies outside conscious awareness** - Priming, TOT phenomenon, blindsight 1. **Priming can speed or slow down processing** - **Facilitative priming** (target stimuli -- BUTTER) are processed faster if **preceded by a related word** (BREAD) - **Negative priming effect** (target stimuli -- PINE) processed slower if preceded by a word related to **target's alternate meaning** (PALM relating to hand) 2. **Tip-of-the-Tongue Experiences (TOT)** - You know you know the word, **but you cannot fully retrieve the word**; paradigms used to generate TOT - Show pictures of famous people or politicians and have participants name them - Ask general knowledge questions to generate TOTs 3. **Blindsight** - **Person cannot consciously see a certain portion of their visual field** but still behave in some instances as if they can see it - Being aware of doing something is distinguishable from doing something **LESSON 6: MEMORY: MODELS AND RESEARCH METHODS** **Memory** - The means by which we retain and draw on our past experiences to use that information in the present. - As a process, it refers to the dynamic mechanisms associated with storing, retaining, and retrieving information about **past experience.** **3 OPERATIONS OF MEMORY** - **Encoding** - you transform sensory data **into a form of mental representation**. - **Storage** - you keep encoded information in memory. - **Retrieval** - you pull out or use information stored in memory. **TASKS USED FOR MEASURING MEMORY (RECALL VS. RECOGNITION)** 1. **Recall** - You may produce a fact, a word, or other item from memory. Ex. Fill in the blank and most essay tests. - Require expressive knowledge, in which you have to produce an answer. Ex. "The term for persons who suffer severe memory impairment is \_\_\_\_" 2. **Recognition** - You select or otherwise identify an item as being one that you have been **exposed to previously**. Ex. Multiple choice or true or false tests. - Referred to as **tapping receptive knowledge**. Receptive means **"responsive to stimulus."** You respond to stimuli presented to you and decide whether you have seen them before or not. Ex. "The term for people with outstanding memory ability is (1) amnesics (2) semanticists (3) mnemonists, or (4) retrograders." **3 MAIN TYPES OF MEMORY RECALL** 1. **Serial Recall** - You recall items in the exact order in which they were presented. For example, remember the following list of comedians in order: Stephen Colbert, Jon Stewart, David Letterman, Conan O\'Brien, Jay Leno. - Repeat the digits in the exact order, 287164. 2. **Free Recall** - You recall items in any order you choose. Ex. Repeat the items in the list in any order in which you can recall them: Dog, pencil, time, hair, money, restaurant. 3. **Cued Recall** - You are first shown items in **pairs**, but during recall you are cued with only one member of each pair and are **asked to recall each mate**. Also called **"paired-associates recall."** - For example, you could ask people to learn the following pairings: Colbert-apple, Stewart-grape, Letterman-lemon, O'Brien-peach, Leno-orange, and then ask them to produce the pairing for Stewart (grape). **IMPLICIT VS. EXPLICIT MEMORY TASKS** 1. **Explicit Memory** - Participants engage in conscious recollection. Ex. They might recall recognize words, facts, or pictures from a particular prior set of items. 2. **Implicit Memory** - We use information from memory, but are not consciously aware that we are doing so. Ex. You can read the word in the photo without problems, although a letter is missing. - Every day you engage in many tasks that involve your unconscious recollection of information. **PRIMING TASK** **Word-completion tasks** - Based on the priming effect. Participants received a word fragment, such as the first 3 letters of a word. They then complete it with the first word that comes to mind. For ex. Imp \_\_\_\_ - Priming is the **facilitation of your ability** to utilize missing information. - In general, participants **perform better when they have seen the word** on a recently presented list, although they have not been explicitly instructed to remember words from that list. **Procedural Memory** - Memory for processes. Examples: riding a bike, driving a car. - Many of the **activities that we do every day** fall under the purview of procedural memories; From brushing your teeth to writing. 1. **Rotary Pursuit Task** - Requires participants to maintain contact between an L-shaped stylus and a small and a small rotating disk. - When a new disk or speed is used, participants do relatively poorly. But with the same disk and speed, they do as well as they had after learning the task, even if they do not remember previously completing the task. 2. **Mirror Tracing** - A plate with the outline of a shape is drawn on it is put behind a barrier where it cannot be seen. - With practice, however, participants become quite efficient and accurate with this task. - Used to study the impact of sleep on procedural memory. **Process-Dissociation Model** - Postulates that **only one task** is needed to measure both implicit and explicit memory. The model assumes that **implicit and explicit memory both have a role** in virtually every response. **INTELLIGENCE AND THE IMPORTANCE OF CULTURE IN TESTING** - **Culture-relevant tests** - measure skills and knowledge that relate to the cultural experiences of the test-takers. **MODELS OF MEMORY (Traditional Model of Memory)** 1. **William James** - Two structures of memory - **Primary memory** -- holds temporary information **currently in use** - **Secondary memory** -- holds information **permanently** or at least for a very long time - **Stores** -- **structures for holding information** - **Memory** -- the information stored in the structure - The **stores are hypothetical constructs** - Concepts that are not themselves directly measurable or observable, but that serve as mental models for understanding how a psychological phenomenon works. 2. **Atkinson-Shiffrin Model** - Richard Atkinson and Richard Shiffrin (1968) proposed an alternative model that conceptualized memory in terms of three memory stores: **sensory store, short-term store, long-term store.** - This emphasizes the passive storage areas in which memories are stored; But it also alludes to some controlled processes that govern the transfer of information from one to another. **Sensory Store** - The initial repository of much information that eventually enters the short and long term stores. - **Capable of storing** relatively limited amounts of information for very brief periods. - **ICONIC STORE** -- a discrete visual sensory register that holds information for very short periods. **SPERLING'S DISCOVERY** - **George Sperling** (1960) -- made the initial discovery regarding the existence of the iconic store. He addressed the question of how much information we can encode in a single, brief glance at a set of stimuli. - **Whole-report procedure** -- participants report every symbol they have seen - **Partial-report procedure** -- participants need to report only part of what they see - Display from a visual-recall task - These data suggest that the iconic store can hold about 9 items. They also suggest that information in the store decays very rapidly. **Subsequent Refinement** - **Averbach and Coriell** (1961): iconic memory can be erased. - **Backward visual making** -- mental erasure of stimulus caused by the **placement of one stimulus where another one had appeared previously**. - To summarize, visual information appears to enter our memory system through an iconic store. Erasure occurs if other information is superimposed on it before there is sufficient time for the transfer of the information to another memory store. **Short-Term Store** - Capable of storing information for somewhat longer periods, but of relatively limited capacity as well. It holds memories for a few seconds and occasionally up to a couple of minutes. - In general, our immediate short term memory capacity for a wide range of items **appears to be about 7 items, plus or minus 2.** - An item can be something simple, such as a digit, or something more complex, such as a word. -- if we chunk string of numbers into larger units, we probably will be able to **reproduce easily** the 21 numerals as 6 items. **Long-Term Store** - Capable of storing information for very long periods, **perhaps even indefinitely**. - Here we keep memories that stay with us over long periods. We hold in it information we need to get us by in our day-to-day lives -- people's names, where we keep things, how we schedule ourselves on different days, and so on. **What is stored in the brain?** - **Wilder Penfield** addressed this question while performing operations on the brains of conscious patients afflicted with epilepsy. He used electrical stimulation of various parts of the cerebral cortex. to locate the origins of each patient\'s problems. - His work was instrumental in plotting the motor and sensory areas of the cortex. He found that patients sometimes would appear to recall memories from their childhoods. - These data suggested to Penfield that long-term memories might be permanent. - **Permastore** -- refers to the very long-term storage of information, such as knowledge of a **foreign language and of mathematics**. - Schmidt and colleagues (2000) studied the permastore effect for names of streets near one's childhood home. Indeed, the author just returned to his childhood home of more than 40 years ago and perfectly remembered the names of the nearby streets. These findings indicate that permastore can occur even for information that you have passively learned. **THE LEVELS-OF-PROCESSING MODEL** **Levels-of-Processing Framework** - Postulates that memory does not comprise 3 or even any specific number of separate. Of course, but rather **varies along a continuous dimension** in terms of depth of encoding. (Craik & Lockhart, 1972). - There are **theoretically an infinite number of levels of processing** (LOP) at which items can be encoded through elaboration -- or successively deeper understanding of material to be learned (Craik & Tulving, 1975) - The deeper the level of processing, the higher, in general, is **the probability that an item may be retrieved** - **Physical** -- visually apparent features of the letters - **Phonological** -- sound combinations associated with the letters (e.g., rhyming) - **Semantic** -- meaning of the word **Self-reference effect** - Participants show **very high levels of recall** when asked to relate words meaningfully to the participants by determining whether the words describe them. - The highest levels of recall occur with words that people consider **self-descriptive**. - Objects can be better remembered, for example, **if they belong to the participant**. **Self-schema** - Is an **organized** **system of internal cues** regarding our attributes, our personal experiences, and ourselves. - Thus, we can richly and elaborately encode information related to ourselves, much more so than other information about other topics. - Two other variables may be of more importance: **the way people process** (elaborate**) the encoding of an item** (e.g., phonological or semantic), and the way the item is retrieved later on. - Two kinds of strategies for elaborating the encoding: - **Within-item elaboration** -- it elaborates encoding of the particular item in terms of its characteristics, including the various levels of processing. - **Between-item elaboration** -- it elaborates encoding by relating each item's features to the features of items **already in memory**. **AN INTEGRATIVE MODEL: WORKING MEMORY** - Most widely used and accepted model today (Baddeley, 2007, 2009) (Unsworth, 2009) **Working Memory** - Holds only the most **recently activated, or conscious**, portion of long term memory, and it moves these activated elements into and out of brief, temporary memory storage. (Dosher, 2003) **Components of Working Memory:** 1. **Visuospatial Sketchpad** -- briefly holds some visual images 2. **Phonological Loop** -- briefly holds inner speech for verbal comprehension and for acoustic rehearsal - We use the phonological loop for a number of every day tasks, including sounding out new and difficult words and solving word problems. - 2 critical components: - **Phonological storage** -- holds information in memory - **Subvocal rehearsal** -- used to **put the information into memory** in the first place - When subvocal rehearsal is inhibited, the new information is not stored. This phenomenon is called **articulatory suppression**. - **Articulatory suppression** is more pronounced when the information is presented visually versus aurally (e.g., by hearing). Thus, **we can remember fewer long words** compared with short words. Without this loop, acoustic information decays after about 2 seconds. 3. **Central Executive** -- both coordinates attentional activities and governs responses. - Critical to working memory because it is the **gating mechanism that decides what information to process further** and how to process this information. - It decides what resources to allocate to memory and related tasks, and how to allocate them. Involved in higher-order reasoning and comprehension and is central to human intelligence. 4. **Subsidiary Slave System** -- perform other cognitive or perceptual tasks 5. **Episodic Buffer** - A limited-capacity system that is **capable of binding information** from the visuospatial sketchpad and the phonological loop as well as from long-term memory into a unitary episodic representation. Integrates information from different parts of working memory-that is, visual-spatial and phonological-so that they make sense to us. - This incorporation allows us to solve problems and reevaluate previous experiences with more recent knowledge. **Neuroscience and Working Memory** - **Phonological loop** - Left hemisphere of the lateral frontal and inferior parietal lobes as well as the temporal lobe. - **Visuospatial sketchpad** -- (short intervals) occipital and right frontal lobes, (longer intervals) parietal and left frontal lobes. - **Central executive** -- frontal lobes - **Episodic buffer** -- bilaterial activations of the frontal lobes and portions of the temporal lobes, including the left hippocampus **MEASURING WORKING MEMORY** - Retention-delay task (old or new?) - Temporally ordered working memory load task (old or new?) - N-back task (find and repeat n-back) - Temporally ordered working memory load task (reproduce in current order -- also referred to as digit-span task) - Temporally ordered working memory load task (reproduce final items in correct order) **MULTIPLE MEMORY SYSTEMS (2 kinds of Explicit Memory)** - **Endel Tulving (**1972) - **Semantic Memory** -- stores general world knowledge. It is **our memory for facts** that are not unique to us and that are not recalled in any particular temporal context. - **Episodic Memory** -- stores personally experienced events or episodes. **HERA (hemispheric encoding/retrieval asymmetry)** - Attempts to account for differences in hemispheric activation for semantic versus episodic memories. - According to this model, there is greater activation in the left than in the right prefrontal hemisphere for tasks requiring retrieval from **semantic memory**. In contrast, there is more activation in the right than in the left prefrontal hemisphere for **episodic retrieval tasks**. **Connectionist Network** - Consists of many different nodes. Unlike in semantic networks, it is not a single node that has a specific meaning, **but rather the knowledge is represented** in a combination of differently activated nodes. - This integrated view suggests that part of the reason we humans are as efficient as we are processing information is that we can handle many operations at ones. Effectively explains **priming effects**, skill learning (procedural memory), and several other phenomena of memory. **PDP (Parallel distributed processing model)** - The key to knowledge representation lies in the connections among various nodes, or elements, stored in memory, not in each individual node. **Priming effect** - Is the **resulting activation of the node**. - **Prime** -- a node that activates a connected node. Ex. Where we ate and whom we were with **(episodic)**, nature of the food we ate **(semantic)**, skills in chopsticks **(procedural)**, embarrassment in spilling tea **(emotional)**. - **Mnemonist** -- someone who demonstrates extraordinarily keen memory ability, usually based on **using special techniques** for memory enhancement. - **Synesthesia** -- experience of sensations in a sensory modality different from the sense that has been physically stimulated (hearing colors, tasting sounds) - **Hypermnesia** -- a process of producing retrieval of memories that would seem to have been **forgotten** - Sometimes loosely referred to as, "unforgetting." Unusual power or enhancement of memory, typically under abnormal conditions such as trauma, hypnosis, or narcosis. **DEFICIENT MEMORY** **Amnesia -- sever loss of explicit memory** - **Retrograde amnesia** -- individuals lose their purposeful memory for events **prior** to whatever trauma induces memory loss. - **Anterograde amnesia** -- the inability to remember events that occur **after** a traumatic event. - **Infantile amnesia** -- the inability to recall events that happened when we were very young. **Alzheimer\'s Disease** - A disease of older adults that causes dementia as well as progressive memory loss. First identified by **Alois Alzheimer in 1907**. - **Dementia** -- **loss of intellectual function** that is severe enough to impair one's everyday life. - **Atrophy --** decrease in size of the brain; especially in the **hippocampus and frontal and temporal brain regions**. The brains of people with the disease show plaques and tangles that are not found in normal brains. - **Plaques** -- dense protein deposits found outside the nerve cells of the brain. - **Tangles** -- pairs of filaments that become twisted around each other. The symptoms are of gradual onset, and the progression is continuous and irreversible. **Donepezil (Aricept)** -- may slightly slow progression of the disease but that it cannot reverse it; slows destruction of the disease but that it cannot reverse it; **slows destruction of the neurotransmitter acetylcholine in the brain**. **Memantine (Namenda or Ebixa)** -- inhibits a chemical that overexcite the brain cells and leads to cell damage and death. - The incidence of Alzheimer\'s disease **increases exponentially with age.** About 1% of people between 70-75 years of age experience an onset of Alzheimer\'s. But between ages 80-85, the incidence is more than 6% a year. - Early-onset, linked to genetic mutation, before even 50 years of age and sometimes as early as the 20s. **HOW ARE MEMORIES STORED?** - **Frontal lobe** -- **store** semantic and episodic memories - **Motor cortex** -- procedural memories - **Prefrontal cortex** - short-term memories - **Temporal lobe** -- formation and storage of long-term semantic and episodic memories and contributes to the processing of new material in short-term memory - **Amygdala** -- vital to the formation of new emotional memories - **Hippocampus** -- plays a pivotal role in the formation of new long-term semantic and episodic memories - **Cerebellum** -- plays an important role in the storage of procedural memories.