Chapter 1 - Brain and Behaviour PDF

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Chapter 1: Introduction to Brain and Behaviour Biopsychology: the Scientific Study of Behaviour. Reasons to Study the Brain: •Explain and cure behavioural disorders •Interesting o is the most complex living organ on earth •Understand our past and evolution •Explore consciousness •Create artificial intelligence Brain Activity is determined by: - Neurons - Memory - Synpases - Genetics - Circuits

What is Behaviour? •Movements, vocalizations, (thinking) •An action •Observable (can measure it) •Produced by the brain

4 Biological Explanations of Behaviour •Physiological (reason, why) •Ontogenic (develops over time, learned behaviour) •Evolutionary (advantage) •Functional (a developed use)

What Is Biopsychology?  Hebb (1949) proposed that psychological phenomena might be produced by brain activity.  Hebb’s work helped discredit the notion that psychological functions were too complex to be derived from physiological activities.  Biopsychology utilizes the knowledge and tools of other disciplines of neuroscience.  Each discipline studies a different aspect of the nervous system that informs our understanding of what produces and controls behavior. Activity in the Brain Causes Behaviour: The Truck/Trailer Analogy: •the trailer cannot move without the truck, but the truck could move without the trailer •behaviour cannot occur without the brain, but the brain can be active without behaviour •if one observes the behaviour then we know the brain is active So, •if we see behaviour, we know the brain is active •if we see a change in behaviour, we know there must be a change in brain structure or function •momentary change in behaviour means momentary change in brain (structure, function, or activity) •lasting change in behaviour means lasting change in brain (structure or function) Basic Ideas: Is it physiological or psychological? Inherited or learned?/ Nature-Nurture debate o Watson, a behaviorist, believed that all behavior is a product oh learning (nurture) o Ethology, the study of animal behaviour in the wild, focuses on instinctive (nature) behaviours •Many factors other than genetics (nature) or learning (nurture) have an impact on behaviour •Nurture now encompasses learning and environment •While it is generally accepted that behaviour is a product of nature and nurture, it has been decided that it is an interactive component as opposed to an additive fashion Cartesian Dualism •Descartes argued that the universe consists of two elements, two separate entities o Physical matter o Human mind (soul, self, spirit) •Problem 1: Brain damage has an impact on psychological functioning o Example: asomatognosia  Deficiency in awareness of parts of one’s own body  Results of damage to the right parietal lobe •Problem 2: some non-human species possess some abilities that were once assumed to be purely psychological and this purely human o Example: chimps with mirrors – display self awareness Other Neuroscience Disciplines

•Neuroanatomy o Structure of the Nervous System •NeuroChemistry o Chemical Basis of Neural Activity •Neuroendocrincology o Interactions between the Nervous System and the Endocrine System •Neuropathology o Nervous System Disorders •Neuropharmacology o Effects of Drugs on Neural Activity •Neurophysiology o Functions and Activities of the Nervous System Divisions of Psychology • Physiological Psychology o Neural mechanisms of behavior o Controlled experiments with direct manipulation of the brain • Psychopharmacology o Controlled experiments of the effects of drugs on the brain and behavior • Neuropsychology o Psychological effects of brain damage in humans o Usually has a clinical emphasis • Psychophysiology o Relation between physiological activity and psychological processes o Example: Visual tracking is abnormal in schizophrenics • Cognitive Neuroscience o The neural basis of cognition (thought, memory, attention, complex perceptual processes) o Functional brain imaging is the major method of cognitive neuroscience. • Comparative Psychology o Comparing different species to understand evolution, genetics, and adaptiveness of behavior o Laboratory and/or ethological research o Evolutionary psychology o Behavioural genetics Human and NonHuman Subjects •Humans are used for many inquiries but we can learn a lot from studying the brains of other species •Simpler brains makes it easier to reveal brain-behaviour interactions •Comparative approach: gaining knowledge by comparing species •Fewer ethical restrictions exist with animals •Humans can follow instructions, make subjective reports, and are less expensive Experiments and NonExperiments •Experiments involve the manipulation of variables •In NonExperiments, the researcher does not control variables of interest o Quasiexperimental Studies: studies of groups of subjects who have been exposed to the conditions of interest in the real world – ie. alcoholics vs. abstainers  These are not real experiments, as potential confounded variables have not been controlled for. o Case Studies: focus on single case or subject  Usually more in-depth than other approaches, but may not be generalizable  Often a source of a testable hypothesis  Generalizability: the degree to which results can be applied to other cases •Experiments involving living subjects require that subjects be placed in various conditions o Between-Subjects Design: Different groups of subjects tested under each condition o Within-Subjects Design: Same group of subjects tested under each condition o The difference between the conditions is the independent variable. o The effect of the independent variable is the dependent variable. o A confounded variable is a variable that affects the dependent variable but is not controlled for.

Control of Confounded Variables • Example: The Coolidge effect: a copulating male who has become tired of his partner will see a return in vigor with a new copulation partner o A copulating male who becomes incapable of continuing to copulate with one sex partner can often recommence copulating with a new sex partner o The Coolidge effect had been demonstrated in males—but does it occur in females? o The confounded variables: A female hamster may be more receptive to a new partner due to novelty or to his vigor (compared to the fatigued former partner). Pure and Applied Research • Pure Research: conducted for the purpose of acquiring knowledge – “what happens if….?” • Applied Research: intended to bring about some direct benefit to humankind – a question or treatment o Applied is often to develop therapeutic drugs or reduce abuse o Often research projects have elements of both Converging Operations • Using multiple approaches to address a single question o E.g. neuropsychology (patients but not experiments) and physiological psychology (experiments but nonhumans) • Example: Korsakoff’s Syndrome • Korsakoff’s syndrome is a condition characterized by severe memory loss and most commonly seen in alcoholics. o Is Korsakoff’s the result of the toxic effects of alcohol on the brain? • Jimmie G o Jimmie G.: An Alcoholic with Korsakoff’s Syndrome (case study) o Korsakoff’s is also seen in malnourished persons who have had little or no alcohol. (quasiexperiment) o Thiamine-deficient rats exhibit memory deficits. (physiological psychology, psychopharmacology) o Alcohol accelerates the development of brain damage in thiamine-deficient rats. • Exploring the possible causes of Korsakoff’s using multiple approaches, or converging operations, leads to more accurate findings. • Korsakoff’s syndrome is the result of thiamine deficiency, but the damage is accelerated by alcohol. Critical Thinking • The ability to evaluate scientific claims by identifying potential omissions or weaknesses in the evidence o Case 1: Delgado claims that a charging bull can be tamed by means of stimulation of its caudate nucleus.  Exciting account reported in popular press  Many possible alternative explanations  Morgan’s Canon: Give precedence to the simplest interpretation for a behavioral observation. • Critical Thinking o Case 2: Moniz wins a Nobel Prize for prefrontal lobotomy.  Used for the treatment of mental illness  Adoption for human therapy based largely on study of a single chimpanzee • Critical Thinking  Inadequate postoperative evaluation of human patients, often by the physician who prescribed the surgery  Undesirable side effects such as amorality, lack of foresight, emotional unresponsiveness, epilepsy, and urinary incontinence  More than 40,000 patients were lobotomized in the USA alone Summary 1. There are many different ways to study behaviour 2. Experiments and non-experiments can be designed in different ways depending on the question you want answered. 1. Often using multiple approaches is the best 3. Critical thinking is the most important skill you can learn in biopsychology. Week 1. 2. 3. 4.

1: Summary Brain activity causes behaviour We can infer brain activity through behaviour Brain activity underlies the mind There are 6 basic approaches to study the brain:

1. 2. 3. 4. 5. 6.

Correlate brain anatomy with behaviour Record brain activity during behaviour Examine the effects of brain damage Examine the effects of brain stimulation Pharmacological interventions Genetic engineering...