PSYCH Notes-3.pdf

The History of Psychology Terminology and Considerations When talking about the history of psych there is mass amounts of bias because of limitations such as gender norms, social conventions, sexism and racism. Etymology ○ Derived from greek psyche,...

The History of Psychology Terminology and Considerations When talking about the history of psych there is mass amounts of bias because of limitations such as gender norms, social conventions, sexism and racism. Etymology ○ Derived from greek psyche, meaning spirit or soul, and logos, meaning to study Defining Psychology The scientific study of mind and behavior ○ Mind:internal,covert behaviors ○ Behavior:external,overt behaviors Hoping to Do Measure and Describe Behavior ○ What behaviors occur ○ Under which conditions ○ How often Explain and Predict Behavior ○ Why does this behavior occur? ○ What triggers it? Modify Behavior ○ Can we make a desirable behavior more likely to occur? ○ An undesirable one less likely? 3 Ways of Framing Explanations Psychological Explanations ○ Thoughts, emotions, and internal motivations Biological Explanations ○ Genes, Hormones, ad physiological processes Environmental Explanations ○ External, physical, and social surroundings The Philosophical Roots of Psychology Greek philosophers asked questions about morality, the mind, and human nature Early physiologists detailed the anatomy of the brain and its connection to behavior ○ Ali ibn al-’Abbas al-majusi (930-990AD) The Mind Body Problem How can we study the mind if it is unobservable? What is the relationship between the body (behavior) and the mind? Monism vs Dualism Rene Descartes (1596-1650) ○ Dualism of mind and body  Mind is an intangible, non physical thing Body is a physical and separate entity Philosophical Dualism:the mind and body are different things Materialistic Dualism: the mind and the body are different and the body is specifically physical Monism vs Dualism Thomas Hobbes (1588-1679) ○ The mind is not a separate, intangible entity; it is the product of the brains physicals action Monism: the mind and the body are the same thing, not separate entities Philosophical Materialism: Mental events are derived from physical events Realism vs Idealism John Locke (1632-1704) ○ Philosophy should focus on understanding the abilities and the extent of the human mind Philosophical Realism: Perception of the world around us is produced by information sent from sensory organs Realism vs Idealism Immanuel Kent (1724-1804) ○ We are born with some innate knowledge of the world and our experiences add to that understanding Philosophical Idealism: Perception of the world around us comes from how the brain interprets incoming sensory information ○ We see things based on existing knowledge that shapes what we are currently experiencing Empiricism vs nativism Philosophical Empiricism: Our knowledge of the world is gained entirely through experience ○ I know that dogs are dangerous because i was bitten by one and it hurt Philosophical Nativism: Our knowledge of the world is innate present from birth ○ I Know that snakes are dangerous because i recoil any time i encounter them even the first time Structuralism and Functionalism Structuralism Wilhelm Wundt (1832-1920) ○ “Father of Modern Psychology” ○ Psychology should use scientific techniques to study the rules that determine how the human mind combines and related various pieces of information  Structuralism ○ School of thought focused on analyzing the basic elements of the mind and trying to determine what those elements were Edward Titchener (1867-1927) ○ Student of Wundt ○ Attempted to better understand our subjective experiences by applying empirical observations Introspection: a systematic process of “looking within” to allow for self-observation Focused on sensations, which they considered the basic elements of consciousness Functionalism William James (1842-1910) ○ Focused on investigating the function or purpose of consciousness Ask “what does the mind do?” Functionalism ○ School of thought focused on the adaptive significance of mental processes Influenced by Darwin's Theory of Evolution Adaptation allows organisms to survive and reproduce Moving to Modern Perspectives The Psychodynamic Perspective Jean-Martin Charcot (1825-1893) and Pierre Janet (1859-1947) ○ French physicians seeking to treat patients with symptoms that had no apparent physical cause Condition called Hysteria Sigmund Freud (1856-1939) ○ Austrian physician who focused on treating individuals with hysteria and nervous disorders ○ Founded psychoanalytic school of thought Idea that the unconscious influences thoughts, feelings, and behaviors in hidden ways Psychoanalysis ○ Therapeutic approach to giving patients insight into their unconscious minds Behaviourism Ivan Pavlov (1849-1936) ○ Russian physiologist studying digestion Classical (or Pavlovian) Conditioning ○ Through experience (learning), a stimulus in the environment can come to elicit a physical response John B. Watson (1878-1958) ○ Thought that psychology should focus on observable behavior, not unobservable inner consciousness ○ Especially interested in predicting behavior by understanding stimulus-response relationship  Behaviorist definitions ○ Psychology The scientific study of behavior ○ Behavior Overt or observable actions B.F. Skinner (1904-1990) ○ American psychologist inspired by Pavlov Interested in active, rather than passive, behavior “No account of what is happening inside the human body, no matter how complete, will explain the origins of human behavior Classical (or Pavlovian) Conditioning ○ Through experience (learning), a stimulus in the environment can come to elicit a physical response Operant (or Instrumental) Conditioning ○ Through experience (learning), an organism can modify their behavior based on the consequences of having carried out those actions in the past Gestalt Psychology Max Wertheimer (1880-1943) ○ German psychologist interested in visual perception ○ Intrigued by perceptual errors in which our interpretations distort sensory reality (i.e., illusions) Gestalt Psychology ○ Interested in understanding how the mind organizes and combines stimuli to create a wholistic perceptual experience Sir Frederic Bartlett (1886-1969) ○ British psychologist interested in false memories ○ Errors in recall show memory is not a simple recording device ○ Exceptions can affect recall Developmental Psychology Jean Piaget (1896-1980) ○ Swiss psychologist interested in understanding mistakes children make as the grew up (such as putting water into a bigger glass and them thinking there is less water) ○ The type of mistakes made provide insight to their mental abilities and how they think Developmental Psychology ○ Interested in how psychological phenomena and abilities change with age Social Psychology Kurt Lewin (1890-1947) ○ German psychologist interested in understanding social behaviour in group settings  ○ Argued against the environment being the driving force of behaviour because individuals subjective perception of the environment is more important in driving behaviour than reality Soloman Asch (1907-1996) and Gordon Allport (1897-1967) ○ Investigated how people come to make inferences about others and how those inferences affect their behaviour towards those individuals Social Psychology ○ Interested in how people interact with one another and how their behaviour can be influenced or influence others Cognitive Psychology Cognitive Psychology ○ Interested in internal, mental processes such as thought, reasoning, memory, and perception Cognitive Revolution in 1960s in response to popularity of behaviorist theories View humans as information processors governed by thought Cognitive Behaviorism Cognitive behaviourism ○ Idea that learning experiences and the environment affect our behaviour by giving us the information we need to behave effectively Evolutionary Psychology Evolutionary Psychology ○ Interested in how natural selection has shaped the human mind and its abilities Neuroscience Neuroscience ○ Interested in function of the brain Cognitive Neuroscience ○ Study of the relationship between the brain and the mind Behavioural neuroscience ○ Study of the relationship between the brain and behaviour Cultural Psychology Culture Psychology ○ Interested in how culture influences behavior Culture ○ Shared experiences, values, beliefs, etc… within a particular group Can be race, country of origin, age, etc… Chapter 3 The Biological Component Outline Neurons ○ Electrical signal transmission ○ Chemical signal transmission The Nervous System ○ Central Nervous system ○ Peripheral nervous system Endocrine system Hemispheric Lateralization Neurons: Communication at the Cellular Level What are Neurons? Neurons ○ Cells that convey sensory information from the body into the brain, carry out operations within our central nervous system, and transmit commands from the brain to body Part of our nervous system Basic structures of behaviour Types of Neurons Motor Neuron: carries commands to the muscles and organs Sensory Neurons:Carry information from the body and outside world into the brain and the spinal cord Interneurons: Neurons which connect one neuron to another in the same part of brain or spinal cord Energy and the Cell Membrae Polarization ○ A state in which there is a difference in electrical charge between the inside and outside of the neuron Volatge ○ Measure of the difference in electrical charge between two points Resting Potential ○ Difference in charge between inside and outside of membrane of a neuron test Energy and the Cell Membrane Ions ○ Atoms that have lost or gained electrons Positive: Na+, K+ Negative: Cl-, A- What Moves the Ions? Force of Diffusion ○ Tendency of ions to move through membrane to less concentrated side  Electrostatic Pressure ○ Force where ions are repelled from similarly charged, attracted to oppositely charged Sodium Potassium Pump ○ Large protein molecules that move sodium ions through cell membrane to outside, potassium ions back inside Ion Channels Ion channels ○ Gated pores in the membrane formed by proteins; limit the flow of ions into and out of the cell Can be chemically gated or electrically gated ○ Chemically Neurotransmitters or hormones ○ Electrically Change in electrical potential of the membrane Depolarization Local potential ○ Partial depolarization Polarity in an area shifts towards zero when disturbed Local potential is a graded potential ○ Varies in magnitude with the strength of the stimulus that produced it If local potential exceeds the threshold for activating electrically gated channels, then an action potential occurs Action Potential: Abrupt depolarization of membrane that allows neuron to communicate Action potential is ungraded ○ All-or-none-law: Occurs at full strength or it does not at all Action potential is nondecremental ○ Travels down the axon without any decrease in size ○ Propagated at each successive point along the way Hyperpolarization Increase in electrical charge across a membrane (more negative) ○ Usually due to the inward flow of chloride ions or outward flow of potassium ions Refractory Periods Absolute Refractory Periods ○ Sodium ion channels are unresponsive to further stimulation A new action potential cannot occur Relative Refractory Period ○ Sodium ion channels could support another action potential, but potassium channels are still open A new action potential can occur, if the stimulation is sufficiently strong enough to overcome the charge Rate Law Rate Law  ○ Axon encodes stimulus intensity not in the size of its action potential but in its firing rate Myelin Sheath Fatty, insulating layer that wraps around the axon ○ Speeds transmission by forcing signals to “Jump” ahead to nodes of ranvier Made up of glial cells ○ Schwann cells in peripheral nervous system One bundle per cell ○ Oligodendrocytes in the central nervous system Multiple bundles per cell Glial Cells Make up the myelin sheath Break down dead neurons Bring in nutrients for neurons Provide physical support to keep neurons in place and form scaffolding for development The Synapse End of axon terminals are terminal buttons Vesicles are bubbles containing neurotransmitters Synapse is fluid-filled space between neurons Neurotransmitters Chemical substances that carry messages across the synapse to either excite other neurons, or inhibit firing Excitatory Inhibitory Increases probability of neuron becoming active Decreases probability of neuron becoming active Acetylcholine Gamma-aminobutyric acid Glutamate Glycine Serotonin Dopamine Dopamine Excitation ○ Excitatory Neurotransmitter onto Depolarizing neurons membrane to Increasing likelihood of action potential Inhibition ○ Inhibitory neurotransmitter onto Hyperpolarizing neurons membrane to Decrease likelihood of action potential 1. Synthesize neurotransmitters 2. Storage in synaptic vesicles 3. Release into synaptic space  4. Binding to receptor sites 5. Deactivation through reuptake or breakdown Drugs and Receptors Agonist ○ Drug increases activity at receptor Antagonist ○ Drug decreases activity at receptor Direct ○ Drug binds at same site Indirect ○ Drug binds at different sites Pre and Postsynaptic Potential Voltage change at receptor sites - postsynaptic potential (PSP) ○ Not all-or-none ○ Changes the probability of the postsynaptic neuron firing Positive Voltage Shift- excitatory PSP Negative voltage shift- inhibitory PSP Excitation and Inhibition Excitatory postsynaptic potential (EPSP) ○ When receptors open sodium channels to produce a partial depolarization of the dendrites and cell body Inhibitory postsynaptic potential (IPSP) ○ When receptors open potassium channels, chloride channels, or both to produce a hyperpolarization of the dendrites and cell body Postsynaptic Integration Spatial Summation ○ Combines potentials occurring simultaneously at different locations on the dendrites and the cell body Temporal Summation ○ Combines potentials arriving a short time apart, from either the same or separate units The Nervous System Directional Terms Dorsal ○ Toward the back Ventral ○ Toward the stomach Anterior ○ Toward the front Posterior ○ Toward the rear  Superior ○ Above another structure Inferior ○ Below another structure Lateral ○ Toward the side Medial ○ Toward the middle Important Terminology An important note ○ Nerve does not equal neuron Neuron ○ Single neural cell Nerve ○ A bundle of axons running together Term only used in the peripheral nervous system Tract ○ Bundle of axons running together in the CNS Organization of the Nervous System Peripheral Nervous System ○ Nerves that lie outside the central nervous system Somatic nervous system ○ Voluntary muscles and sensory receptors Autonomic nervous system ○ Controls automatic, involuntary functions Sympathetic ○ Fight or flight response Parasympathetic ○ Stop Central nervous system ○ Brain and spinal cord Afferent ○ Toward the CNS Efferent ○ Away from CNS Early History of Brain Studies Invention of the microscope allowed scientists to separate out individual neurons by hand Staining techniques allowed scientists to visualize neurons in preserved tissues Improved understanding of structures, but what about functions? Early 1900s started to see reliable methods of recording electrical activity in the brain Damage Studies and Lesioning Damaging areas to alleviate symptoms ○ Epilepsy  ○ Prefrontal lobotomy Disconnect frontal lobe and thalamus ○ Side-effects Lesion studies ○ What happens when this part is damaged Transcranial Magnetic Stimulation A technique that allows scientists to enhance or depress activity in specific parts of the brain Metal coil produces a magnetic field that can penetrate up to 2cm into the brain Pulse timing and duration can be modified to increase firing or decrease firing Also used as treatment Computerized Tomography (CT or CAT) Produces computer enhanced X-ray of the brain Builds 2D picture of the brain based on differential absorption of x-rays ○ Tissue density affects absorption ○ Control which axis we take images on Ca stitch multiple images together ○ Reveals gross features of the brain Does not resolve brain structure well Magnetic Resonance Imaging Uses strong magnetic field to align certain molecules, then a quick and strong burst of radio waves to disrupt alignment ○ Measure energy released when the molecules snap back into alignment with magnetic field Different molecules release different levels of energy ○ Allows us to resolve soft tissues much better than CAT scans Functional Magnetic Resonance Imaging (fMRI) Detects changes in blood oxygenation, blood flow ○ Tied to neural activity High activity=high oxygen use and high blood flow Specifically, hemoglobin ○ Need to consider background activity ○ Better spatial and temporal resolution than a PET scan Diffusion Tensor Imaging (DTI) Builds a picture of water movement (diffusion) in the brain using an MRI scanner ○ Observe blood flow along specific neural tracts Measure rate and direction ○ High spatial resolution and directionality ○ Helps us understand connectivity Positron Emission Tomography (PET) Track levels of a harmless radioactive material that is injected into the subjects bloodstream ○ Higher activity in brain areas = more blood flow, higher concentration of the radioisotope  ○ Similar logic to fMRI Near Infrared Spectroscopy (NIRS) Measures changed in blood oxygenation ○ Shines near IR light through the skull ○ Detects attenuation of reemerging light ○ Indirect measure of brain activity Electroencephalography (EEG) Measures electrical activity via electrodes ○ Can be inter or intra cranial Electrodes either on or in the skull ○ Very good time resolution Milliseconds The Spinal Cord Nerve bundles in spinal cord carry information to and from brain Nerves in each section connect with different areas in body Dorsal horn contains afferent endings (axons) of sensory nerves Ventral horn contains cell bodies (and dendrites) of efferent nerves Both connected by interneurons (aka relay neurons) The Brain Hindbrain ○ Vital functions and coordinating movements Midbrain ○ Reflex actions and voluntary movements Forebrain ○ Highly developed, numerous functions The Hindbrain Regulation of basic life functions Connects peripheral and central nervous systems The Medullas Controls heart activity and circulation Regulates breathing Involved in coordinating swallowing and digestion All sensory and motor nerve tracts ascend from the spinal cord and descend from the brain Pons Relay station for signals between higher levels of the nervous system and lower levels ○ Coordinates with the cerebellum and rest of the brain Connects to muscles and glands in face and neck Cerebellum Controls bodily coordination, balance, and muscle tone ○ Active in fine motor control and smoothing out movements Helps with sequences of actions Involved in procedural memory ○ Memory of motor skills The Midbrain Reticular formation Superior and inferior colliculi Red nucleus Substantia nigra Tectum vs tegmentum Reticular Formation Helps to regulate awareness and attention ○ Filter out irrelevant stimuli Regulates sleep and wakefulness ○ Aka arousal Coordinates several brain areas The Forebrain Basal ganglia Limbic system Thalamus Hypothalamus Cerebral cortex Basal Ganglia Controls voluntary and involuntary movement Principal structures ○ Caudate nucleus ○ Putamen ○ Globus pallidus Limbic System Principal Structures ○ Amygdala ○ Hippocampus ○ Cingulate cortex Limbic system regulates ○ Emotional and sexual behaviours ○ Memory ○ Spatial navigation Amygdala ○ Increases electrical activity in its neurons when we are under threat Fight or flight response Remember events tied to strong emotions Receives sensory input to determine emotional value/intensity of a stimulus Hippocampus ○ Activated when we form memories Assists the process of memory formation Cingulate gyrus ○ Helps focus our attention and thoughts on things that are unpleasant to us  Physical and emotional pain Thalamus Relays incoming sensory information through groups of neurons that project to the appropriate region in the cortex Also actively filters incoming sensory information Hypothalamus Regulates the autonomic and endocrine systems ○ Involved in hunger responses, sexual behaviour, temperature control, and aggression Homeostasis Geography of the Brain Cerebral Cortex ○ Outer layer of frontal lobe Cerebral hemispheres ○ Large, wrinkled structures dominating brains appearance The dorsal or superior part of the brain and that are covered by the cortex Surface Features Cortex ○ Outer surface of brain; literally, “bark” Mostly made up of the cell bodies of neurons Gyrus ○ Each ridge in surface of the brain Plural = gyri Sulcus ○ Groove or space between two gyri Plural = sulci Fissure ○ Large groove or space between two gyri Interior Features Lateral ventricles ○ Winged-shaped cavities Filled with cerebrospinal fluid (CSF) made by a network of interconnected blood vessels CSF ○ Suspends the brain, act as as a shock absorber Provides stable environment for optimal function Hemispheric Divisions Each hemisphere is divided into four lobes ○ Frontal (executive function) ○ Parietal (sensory integration) ○ Temporal (auditory, taste, smell, memory) ○ Occipital (visual) Temporal Lobes Temporal lobes  ○ Regions containing the auditory projection area, visual and auditory association areas, an additional language area, and structures important in learning and memory Inferior temporal cortex ○ Plays major role in visual identification of objects Other interesting concepts Aphasia ○ Difficulty processing or producing language Mirror neurons ○ Our actions and the actions of others Plasticity ○ Making new connections ○ Adapting after damage The Endocrine System The Endocrine System A series of glands throughout the body that release hormones ○ Hormones: chemical messengers in the bloodstream Serves as a secondary control system ○ Feedback to the nervous system Endocrine Glands Pituitary ○ The director, growth hormone Thyroid ○ Metabolic rate Adrenal ○ Salt and carbohydrate metabolism Pancreas ○ Sugar metabolism Gonads ○ Sex hormones CNS Endocrine Control System Hypothalamus ○ Secretes hormones and controls the pituitary gland via direct nerve stimulation and chemicals Pineal Gland ○ Secretes melatonin to regulate sleep cycles Pituitary gland ○ Secretes hormones that affect sexual behaviour, reproduction, circulatory function, hunger, and responses to aggression Genetics Crash Course  What are Genes? Organization of Information DNA (deoxyribonucleic acid) ○ String of nucleotides containing genetic information ○ Nucleotides Adenine(A), Thymine(T), Guanine(G), and Cystonine(C) Gene ○ Basic unit of hereditary; used as instructions to make proteins Chromosome ○ Paired complimentary strands of DNA compacted for protection and storage From Gene to Trait Proteins ○ Molecules made up of chains of amino acids that are assembled within the cytoplasm Wide array of functions Activation or deactivation of a gene can increase or decrease protein production ○ Change in protein levels can change functioning in and around cells Genotypes vs Phenotypes Genotype ○ Persons specific genetic makeup Present from birth and effectively unchanging Phenotype ○ Observable characteristics or trait and individual displays due to both their genetic makeup and the effects pf their environment Can be altered by other genes, the environment, etc Which trait do we see? In somatic cells: 2 pairs of each chromosome ○ But with two copies, which do we see? If a gene in a pair is dominant, the characteristic it controls will be displayed If a gene in a pair is recessive, the characteristic will not show up unless the partner gene is also recessive Polygenic Transmission When a number of gene pairs combine to crease a single phenotypic trait Epigenetics Epigenetics ○ Lasting changes in gene expression during development that are not caused by the genes themselves ○ DNA Methylation Adding a methyl group to DNA making a off switch ○ Histone modification Chemical changes to histones that modify proteins that condense DNA and make a on or off switch Evolution What is Evolution Evolution ○ A gradual change in heritable traits within a population of individuals over time Monitor frequency of certain genes (and the traits they influence) within the population What is Natural Selection Natural Selection ○ The process whereby the genes that produce traits that increase the likelihood of survival and reproduction are maintained in the gene pool and become more common in that population over time This makes evolution occur Oversimplified as survival of the fittest Cautions about Natural Selection Natural selection acts on the traits that provide a fitness benefit and by doing so influence the genes that produce those traits ○ Only works on heritable traits A trait may be adaptive (beneficial for fitness) in one environment, but if the environment changes, the former adaptation may no longer be beneficial Natural Selection Acts from Two Sides Mutation ○ Change in the DNA sequence of an organism that occurs because of errors Changes to the DNA sequence can lead to changes in the protein structure produced ○ Changes caused by mutations can be bad, neutral, or good Bad is removed from population Neutral is up to chance Good is adaptation Genetic Relatedness and Heritability Genetic Relatedness Parent and child = 50% Grandparent and Grandchild = 25% Between siblings = 50% Between twins ○ Identical (monozygotic) = 100% ○ Fraternal (dizygotic) = 50% Heritability Heritability ○ How much of the variation in a characteristic within a population can be attributed to genetic differences Heritabilty Coefficient ○ Estimate of how much of a characteristic is due to genetic factors  Aka Heritability Estimate Concordance Rate Concordance Rate ○ Rate of co-occurrence of a characteristic among individuals What is the proportion of cases in which both members of a pair have a certain trait Higher rates with increasing relatedness = possible genetic contribution Types of Studies Family Studies Ask if traits are more common within a family vs the rest of the population Track pattern of inheritance across the generations Adaptation Studies Share genes, but not environment, with biological relatives Share environment, but not genes, with adoptive relatives Twin Studies Different methodology from adoption studies - separates genetic and environment influences Agreement between adoption and twin studies increases confidence in results Francis Galton - conducted first twin study in Britain in 1875 If theres mainly a genetic contribution ○ MZ twins should resemble each other about twice as much as DZ twins If theres mainly an environmental contribution ○ MZ and DZ twins should resemble each other equally Example: Religion