Cognitive Psychology Chapter 3: Cognitive Neuroscience PDF

Cognitive Psychology The brain and therefore our thoughts and behaviors are shaped by evolution Chapter 3: Cognitive Neuroscience Adaptations Cognitive Neuroscie...

Cognitive Psychology The brain and therefore our thoughts and behaviors are shaped by evolution Chapter 3: Cognitive Neuroscience Adaptations Cognitive Neuroscience ◦ Mechanisms such as behaviors or physical traits that enhance the reproductive success Cognitive Neuroscience – field of study of organisms that possess them linking the brain and other aspects of the ◦ Our current thoughts or behaviors are nervous system to cognitive processing and, adaptations that benefitted our ancestors ultimately, to behavior ◦ Localization of Function – whether The “mind” seems separate from the brain, specific areas of the brain control specific apparently non-physical abilities or behaviors Research suggests that the mind is a product The Mission of Cognitive Neuroscience – of the brain determine how the brain processes information, builds memories, and makes All of our thoughts and behaviors result from decisions the interactions of the physical parts of the - figure out what makes us who we are brain Neuroscience is a Relatively New Field – From Neuron to Brain: Structure of the combines biology and psychology to connect Neurons neural functions to behaviors - “neuroscience” was first used in the 1960s Neurons – individual neural cell - transmits electrical signals from one location Which Parts Matter? to another in the nervous system Explanations in cognitive neuroscience can Soma – responsible for the life of the neuron be at the level of individual molecules or at the - connects the dendrites to the axon level of systems or neurons Dendrites – receive information from other All thoughts, memories, moods, and decisions neurons are brought about by the physical substance of the brain Axon – long, thin tube that extends from the soma and responds to the information, when Alterations to the anatomy or chemistry of the appropriate brain result in changes to behaviors Myelin – white fatty substance which FIGURE 1.6 Three insulates and protects axons and speeds up patients with deficits in the conduction of information conscious visual perception as a result of Nodes of Ranvier – small gaps in the myelin injuries to specific coating along the axon, which serve to regions of the brain. (a) increase conduction speed even more The injured regions of the brain in each patient. Terminal buttons – small knobs found at the (b) The corresponding ends of the branches of an axon diagrams show the deficits in each patient’s Synapse – small gaps, which serve as a visual field (gray) juncture between the terminal buttons of resulting from the injury. Indicator arrows added neuron and dendrites by Oxford University Press. From Neuron to Brain: Organization of the Static Imaging Techniques – allow for the Nervous System observation of large abnormalities of the brain, such as damage resulting from strokes and Peripheral nervous system (PNS) – all of tumors the nerve cells except those of the brain and - examples: the spinal cord ◦ CT: computerized axial tomography - consists of: ◦ MRI: magnetic resonance imaging – a ◦ Somatic voluntary part (sensory and motor strong magnetic field is passed through the nerves) brain of a patient and a rotating scanner ◦ Autonomic involuntary part detects various patterns of electromagnetic ▪ Sympathetic (activated under stress) changes in the molecules of the brain ▪ Parasympathetic (maintains body functions) Metabolic Imaging – relies on changes that take place within the brain as a result of Central nervous system – consists of: increased consumption of glucose or oxygen in ◦ Brain – most directly controls our thoughts, active areas of the brain emotions, and motivations - examples: ◦ Spinal Cord ◦ PET: positron emission tomography – increased glucose consumption in active Methods of Cognitive Neuroscience brain areas ◦ fMRI: functional magnetic resonance Postmortem Studies imaging – increased oxygen consumption in ◦ Characterization: active brain areas - researchers look carefully at the behavior of people who show signs of brain damage Critical Analysis of the Brain while they are alive - after the patients die, the researchers Is the Brain Equipped to Understand examine the patient’s brains for lesions Itself? ◦ Examples: - The brain has evolved to control three specific - Paul Broca’s patient Tan classes of behaviors: ▪ Speech problems, linked to lesions in an ◦ Homeostatic behaviors, which maintain a area of the frontal lobe now called Broca’s normal range of survival parameters area ◦ Agonistic behaviors, which defend against rivals Animal Studies ◦ Reproductive behaviors, which promote ◦ Single-cell recordings – microelectrodes the continuation of the species are inserted into the brain of an animal to measure the activity of a single neuron ◦ Selective lesioning – surgically removing or damaging part of the brain to observe resulting functional deficits Electrical Recordings ◦ EEG – recording of electrical activity in the brain, which appears as waves of various widths and heights ◦ ERP – EEG waves associated with a particular event or task averaged over a large number of trials ▪ Advantage: very good temporal resolution  Biases and Pitfalls in Human Cognition Healing the Disordered Brain - The anchoring bias refers to the tendency to - Depression affects as many as 1 in 10 be overly influenced by a single observation, individuals typically the first observation - Techniques such as rTMS and deep brain - The confirmation bias is the tendency to stimulation have been identified that can help seek out and emphasize information that alleviate the symptoms of conditions such as matches our existing beliefs depression, Parkinson’s disease, and - There is a long list of biases and heuristics obsessive-compulsive disorder that adversely affect our ability to observe and - FIGURE 1.29 Deep draw accurate conclusions about our own brain stimulation. A skull brain: X-ray of a patient who ◦ Availability heuristic has undergone surgical ◦ Affect heuristic implantation of a ◦ Illusory correlation pacemaker-like device ◦ Belief bias known as a deep brain stimulator. These A Toolbox of Critical-Thinking Technique devices are used to - The scientific method provides a systematic treat an increasingly way to study a process and avoid biases and wide variety of heuristics neurological and psychiatric conditions ◦ Make observations about the world including Parkinson’s disease, obsessive– ◦ Develop a hypothesis to explain the compulsive disorder, and major depression observations ◦ Generate testable predictions about the Enhancing Human Abilities hypothesis - Understanding how humans make decisions ◦ Perform experiments to test the predictions can provide insight into how to encourage us to - The results of one experiment help to refine make better decisions the hypotheses for the next experiment - Brain interface devices, such as cochlear - Experiments are repeated and extended to implants and implanted electrodes to enable show they are reproducible paralyzed patients to move devices outside - Results are subjected to independent peer their own body, can restore lost functions to review to reduce the biases that may have individuals been introduced by the experimenter Blueprints for Artificial Cognition - Researchers are learning from the brain to improve the abilities of our computing devices, such as speech recognition, locomotion, and object recognition - Such artificial “neural networks” are now being used to recognize patterns of brain activity in brain imaging studies - Much remains to be done to find artificial equivalents to much human cognition - Eyewitnesses are very compelling in the courtroom, but are notoriously unreliable - Cognitive neuroscience can help understand and explain the factors that influence the memory of such witnesses The Payoffs of Cognitive Neuroscience Brain-Compatible Social Policies - An increased understanding of the Concepts of Attention and Consciousness neuroscience of addiction can inform our policies regarding punishment and treatment of Preconscious Processing – information that addicts is available for cognitive processing but that - Such research suggests ways to attack the currently lies outside of conscious awareness demand for the drugs within the reward system exists at the preconscious level of awareness of the brain ◦ Priming – processing of certain stimuli is - Modern neuroscientific research has facilitated by prior presentation of the same or important implications for criminal punishment similar stimuli. Sometimes we are aware of and rehabilitation the prime sometimes we are not. Even when - It is estimated that about 25% of the we are not aware of the prime, the prime will American prison population has a mental influence the processing of the target illness, so providing appropriate care is ▪ Antony Marcel (1983) important - participants had to classify series of words into various categories (e.g. pine-plant) Chapter 4: Attention and Consciousness - primes where words with two meanings such as palm followed by target word (tree Attention – is the means by which we or hand) actively process a limited amount of - e.g., Is this a plant? Prime – PALM, Target information from the enormous amount of – TREE information available through our senses, our - if the participant was consciously aware of stored memories, and our other cognitive seeing the word “palm”, the mental pathway processes for only one meaning was activated - if the word “palm” was presented so briefly Consciousness – more directly concerned that the person was unaware of seeing the with awareness – it includes both the feeling of word, both meanings of the word appeared awareness and the content of awareness, to be activated some of which may be under the focus of ◦ Tip-of-the-tongue phenomenon – we try to attention remember something that is known to be stored in memory but that cannot quite be The Nature of Attention and Consciousness retrieved - people who can not come up with the Different conceptions of consciousness word, but who thought they knew it, could ◦ Biopsychological – different levels of identify the first letter, indicate the number of arousal (sleep, coma, hyperactivity) syllables, or approximate the word’s sounds ◦ Meta-cognitive – reflection on your own ◦ Blindsight – lesions in some areas of the cognitive processes visual cortex - being aware of cognitive processes - patients claim to be blind ◦ Psychoanalytic - when forced to guess about a stimulus in ▪ Unconscious information – we do not the “blind” region, they correctly guess have access to it in normal awakened state locations and orientations of objects at ◦ Phenomenological – what it is like to have above-chance levels an experience of something - individual, subjective aspects of experience Controlled Versus Automatic Processes – many tasks that start off as controlled Relationship between attention and processes eventually become automatic ones consciousness ◦ Controlled processes – require intentional ◦ Attention + Consciousness effort; full conscious awareness; consume ◦ No attention + No Consciousness many attentional resources; performed ◦ Attention + No Consciousness serially; relatively slow ◦ No attention + Consciousness ◦ Automatic Processes – little or no intention or effort; occur outside of conscious  awareness; do not require a lot of attention, simply scan the environment for those performed by parallel processing; fast features ◦ Automatization – the process by which a ◦ Conjunction search – we look for a procedure changes from being highly particular combination of features conscious to being relatively automatic Feature-Integration Theory (Anne Habituation – we become accustomed to a Treisman) – each of us has mental map for stimulus, we gradually notice it less and less representing the given set of features for a (e.g. music and studying) particular item (shape, size, color features) ◦ Dishabituation – a change in a familiar - during feature searches we monitor the stimulus prompts us to start noticing the relevant feature map for the presence of any stimulus again activation in the visual field ◦ Sensory adaptation – physiological - during conjunction searches, we can simply phenomenon; not subject to conscious use the map of features, we must conjoin two control; occurs directly in the sense organ, not or more features into an object representation in the brain at a particular location Attention Similarity theory (Duncan and Humphreys) – as the similarity between target and distracter 1. Vigilance and Signal Detection increases, so does the difficulty in detecting the target stimuli We vigilantly try to detect whether we did or - factors influencing search: did not sense a signal (a particular target ◦ similarity between the target and the stimulus of interest) distracters ◦ similarity among distracters Vigilance – a person’s ability to attend to a field of stimulation over a prolonged period, Guided search theory (Cave and Wolfe) – during which the person seeks to detect the all searches involve two consecutive stages appearance of a particular target stimulus ◦ Parallel stage – simultaneous activation of - example: Mackworth, 1948 – participants all the potential targets were watching when a clock hand took a ◦ Serial stage – sequential evaluation of each double step of the activated elements - substantial deterioration after half an hour of observation Movement-Filter theory (McLeod et al) – - vigilance can be increased with training movement can both enhance and inhibit visual search 2. Search ◦ Movement-filter – can direct attention to stimuli with a common movement Search – scan the environment for particular characteristics features - whereas vigilance involves passively waiting 3. Selective Attention for a signal stimulus to appear, search involves actively seeking out the target Stroop Effect (Stroop, 1935) – demonstrates the psychological difficulty in Distracters – nontarget stimuli that divert our selectively attending to the color of the ink and attention away from the target stimuli trying to ignore the word that is printed with the - can cause false alarm ink of that color - since reading is an automatic process (not 2 kinds of search: readily subject to your conscious control) you ◦ Feature search – when we can look for find it difficult intentionally to refrain from some distinctive features of a target we reading and instead to concentrate on identifying the color of the ink  The attentional system must perform two or The Cocktail Party Problem (Cherry, 1953) more discrete tasks at the same time – the process of tracking one conversation in the face of the distraction of other Much better performance at two or more conversations automatic tasks (driving a car and speaking) than controlled tasks (writing and Shadowing – listening to two different comprehending read text) messages and repeating back only one of the messages as soon as possible after you hear it Dichotic presentation – listening to two different messages (presenting a different message to each ear) and attending to only one of them Filter and Bottleneck Theories ◦ Broadbent’s Model – we filter information right after it is registered at the sensory level ◦ Moray’s Selective Filter Model – the selective filter blocks out most information at the sensory level, but some highly salient messages are so powerful that they burst through the filtering mechanism (e.g. your name) ◦ Treisman’s Attenuation Model – we preattentively analyze the physical properties of a stimulus (stimuli with target properties) - we analyze whether a given stimulus has a pattern, such as speech or music - we sequentially evaluate the incoming messages, assigning appropriate meanings to the selected stimuli messages ◦ Deutsch and Deutsch’s Late Filter Model – placed the signal-blocking filter later in the process, after sensory analysis and also after some perceptual and conceptual analysis of input had taken place ◦ Neisser’s Synthesis – two processes governing attention: ▪ Preattentive processes (rapid, automatic, parallel) ▪ Attentive processes (controlled, occur later, serial) Attentional-Resource Theories – we have attentional resources specific to a given modality - explains why we can study and listen to a music but not listen to news 4. Divided Attention