Biological AspectsBiological Aspects

Kimberley A. ClowKimberley A. Clow

kclow2@uwo.cakclow2@uwo.cahttp://instruct.uwo.ca/psychology/257e-570http://instruct.uwo.ca/psychology/257e-570

Office Hour: Thursdays 2-3pmOffice Hour: Thursdays 2-3pmOffice: S302Office: S302

OutlineOutline

Welcome to the BrainWelcome to the Brain

The Nervous SystemsThe Nervous Systems– Neural CommunicationNeural Communication

ExtraversionExtraversion– Return to Eysenck’s Arousal TheoryReturn to Eysenck’s Arousal Theory– Gray’s InterpretationGray’s Interpretation

SociobiologySociobiology– Prosocial Behaviour & LearningProsocial Behaviour & Learning– Mate SelectionMate Selection

The CortexThe Cortex

Hemisphere LateralizationHemisphere Lateralization

Gender Differences?Gender Differences?

Messages from Brain Travel by Messages from Brain Travel by Nervous SystemNervous System

The Central Nervous The Central Nervous System is the System is the Communications Communications Highway of the bodyHighway of the body

SpinalCord

Brain

Nerves

Somatic Nervous SystemSomatic Nervous System

Sensory NeuronsSensory Neurons– input from body to Central input from body to Central

Nervous SystemNervous System

Motor NeuronsMotor Neurons– output from Central output from Central

Nervous System to Nervous System to control muscle control muscle movementsmovements

InterneuronsInterneurons– sensory-motor relay within sensory-motor relay within

Central Nervous SystemCentral Nervous System

Autonomic Nervous SystemAutonomic Nervous System

Neurons are the MessengersNeurons are the Messengers

NeuronsNeurons– Information Information

Processing CellsProcessing Cells– 100 billion 100 billion

neurons in the neurons in the brain!brain!

Neural Communication

Types of NeurotransmittersTypes of Neurotransmitters

NeurotransmitterNeurotransmitter Source and FunctionSource and Function

Acetylcholine (ACH)Acetylcholine (ACH) Controls muscles; attention and memoryControls muscles; attention and memory

Alzheimer’s DiseaseAlzheimer’s Disease

DopamineDopamine Controls muscles; can cause hallucinationsControls muscles; can cause hallucinations

SchizophreniaSchizophrenia

EndorphinsEndorphins Suppresses painSuppresses pain

Gamma aminobutyric Gamma aminobutyric acid (GABA)acid (GABA)

Works against neurotransmitters, especially dopamineWorks against neurotransmitters, especially dopamine

NorepinephrineNorepinephrine Regulates mood; increases arousal and alertnessRegulates mood; increases arousal and alertness

Mood Disorders, Eating DisordersMood Disorders, Eating Disorders

SerotoninSerotonin Opposition to norepinephrine, suppresses activity, Opposition to norepinephrine, suppresses activity, causes sleepcauses sleep

Anxiety Disorders, Mood Disorders, Eating DisordersAnxiety Disorders, Mood Disorders, Eating Disorders

Brain Still in Control!Brain Still in Control!

Altering of Altering of neurotransmitters neurotransmitters based on messages based on messages from brainfrom brain

Absence or Absence or overabundance can overabundance can create whole new set create whole new set of consequencesof consequences

Biology on PersonalityBiology on Personality

How do you show that personality has a How do you show that personality has a biological basis?biological basis?– Relate behaviours to brain structuresRelate behaviours to brain structures– Heritability or genetic contributionsHeritability or genetic contributions

Twin StudiesTwin Studies

– Observations in human & nonhuman animalsObservations in human & nonhuman animals– Evidence in many different culturesEvidence in many different cultures

Cultural UniversalsCultural Universals

– Stability over timeStability over time

Remember Eysenck?Remember Eysenck?

3 Factors of Personality3 Factors of Personality– ExtraversionExtraversion– NeuroticismNeuroticism– PsychoticismPsychoticism

Eysenck’s ModelEysenck’s Model

Extraversion - IntroversionExtraversion - Introversion

Optimal Arousal LevelsOptimal Arousal Levels

GrayGray

Model of ResponsivenessModel of Responsiveness

Dopamine & Extraversion?Dopamine & Extraversion?

Encephalitis LethargicaADHD

SociobiologySociobiology

Born from Darwin’s Theory of EvolutionBorn from Darwin’s Theory of Evolution– Survival of the FittestSurvival of the Fittest

Too many people; Too few resourcesToo many people; Too few resources

– Natural SelectionNatural SelectionFavours behaviours that maximize survival and Favours behaviours that maximize survival and reproductive successreproductive success

– The survival of your genesThe survival of your genes

Inclusive FitnessInclusive Fitness– Your siblings and relations have your genes Your siblings and relations have your genes

too!too!

Prosocial BehaviourProsocial Behaviour

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60606060

20202020

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40404040% Helping

High Medium Low None

Degree of Relation

Nepotism in Action

LearningLearning

Prepared LearningPrepared Learning– Some things are Some things are

easier to learn than easier to learn than othersothers

LanguageLanguage

– We learn some We learn some associations but not associations but not othersothers

Animal Specific Animal Specific

What’s Love Got to Do With It?What’s Love Got to Do With It?

Argument that “love” is just an adaptation to insure survival of the species– It keeps parents together to provide protection of

offspring who require a lengthy period of development before they can fend for themselves

– Evident in gender differencesMate selection

Sexual Relations

Desirable Qualities in Mate

Views on Infidelity

Human Reproductive StrategiesHuman Reproductive Strategies

Male StrategyMale Strategy– Inseminate as many females as possibleInseminate as many females as possible– Promiscuous sexual behaviourPromiscuous sexual behaviour– Devote only minimal resources to child careDevote only minimal resources to child care

Female StrategyFemale Strategy– Choose mate very carefullyChoose mate very carefully– Monogamous sexual behaviourMonogamous sexual behaviour– Remain attached to mate for resourcesRemain attached to mate for resources

When to Have SexWhen to Have Sex

Number of PartnersNumber of Partners

ChastityChastity

SuccessSuccess

Physical AttractivenessPhysical Attractiveness

AgeAge

FidelityFidelity

What would bother you What would bother you more?more?– Sexual InfidelitySexual Infidelity– Emotional InfidelityEmotional Infidelity