Biological and Behaviorist Perspectives Flashcards
Personality and Intelligence – inherited (nature) or acquired (nurture) – or both?
This and the next lecture compare the biological perspective - the view that our intelligence and personality are genetically/biologically determined – with the view from the other extreme - behaviorism - that they are determined not at all by biological factors, but solely by learning via our experiences and associations we make in interacting with the environment.
Biological determinism or environmental determinism respectively.
Various aspects of the biological and behaviourist approaches are discussed, together with ‘Quantitative Genetics’ – where the relative contribution of biological and environmental factors to intelligence and personality is considered.
Finally, therapeutic techniques relating to the two approaches are then described.
This provides a basis for future lectures on ‘interactionist’ approaches to personality, e.g. humanistic, cognitive and psychoanalytic perspectives - which advocate consideration of both the person’s biology and the situation/ environment - AND the interaction between them - in determining our intelligence and personality.
Early Biological Thoughts
Physiognomy, e.g. body types (endomorph, mesomorph, and ectomorph) - or facial features as basis for judgement.
Hippocrates’ sanguine, melancholic, choleric and phlegmatic types related to predominance of ‘humours’ (body fluids of blood, black bile, phlegm, etc).
Evolutionary Personality Psychology (Buss, ARP1991).
Evolution by natural selection. Adaptive strategies for survival/ reproduction based on broad traits shared with other primates:-
• activity - energy output • fearfulness • impulsivity • sociability • nurturance - includes altruism • aggressiveness • dominance
Adaptation in terms of ‘reproductive success’ through traits which help in acquiring resources, attracting mates, and providing a safe environment.
Biologically-based sex differences in personality? ‘Opposite sexes’? - or cultural socialisation of gender roles (sex-role stereotyping)?
Behaviorism.
Tabula rasa. Environmental influences. Nurture. Acquired.
Personality a result of learning - a product of learned associations.
3.1 Watson (1913):- ‘Give me a dozen healthy infants……’.
Little Albert and fear of rats.
3.2 Pavlov (1927):- classical conditioning where ‘acquisition of a response’ (and therefore subsequent behaviour) is by associating two events which occur together. Personality the result of a bundle of CR’s.
UCS + CS —> UCR
food bell salivation
after several trials…….
CS —> CR
bell salivation
Skinner’s Operant Analysis of Personality
rewards (positive and negative reinforcements) and punishments from experiences with external environmental factors. Reinforcements strengthen response and consequently learning and subsequent behaviours.
Shaping
Extinction
Schedules of reinforcement:- continuous or partial (variable interval or variable ratio: fixed interval or fixed ratio). More irregular the reinforcement, the longer the time before extinction.
Walden Two (1948).
Molecular genetics
Identifies specific genes which influence behaviour.
Genetic inheritance. Deoxyribonucleic acid (DNA) research. Genes. Human Genome Project. Genetic mapping. Genotyping. Genomics.
Genes and Intelligence – some examples
dysbindin-1 gene (DTNBP1) previously demonstrated to be associated with schizophrenia, may also be linked to general cognitive ability (UCLA, 2006)
IGF2 receptor gene twice as common in high intelligence children (Plomin, 1998)
Plomin (2007) identified six genes that were strongly associated with high or low intelligence, but even the most powerful of these accounted for just 0.4 per cent of the variation in intelligence between individuals. The six together accounted for about 1 per cent of the variation in intelligence.
Cortical Arousal Theory (Eysenck,1985)
Using a psychophysiological approach, suggests a ‘biological basis’ for certain personality types (extraversion and neuroticism). Electroencephalogram (EEG) ) in measures of arousal from the reticular activating system (RAS) > the sympathetic part of the autonomic nervous system (ANS).
Introverts assumed to have innately higher levels of arousal than extraverts. I’s amplify inputs more than do E’s. Inverted U arousal/performance, where intermediate levels of arousal give ‘positive hedonic tone’. Campbell and Hawley (1982) on student study habits, with E bored with low levels of stimulation. Would E or I be the best air traffic controller? N similar to E.
Gray Reinforcement Sensitivity Theory (1964)
Behavioral Activation System (BAS) and Behavioural Inhibition System (BIS).
Latter more active in Neurotics: former in extraverts.
Different regions of the brain, e.g startle reflex and the brain stem.
Quantitative genetic research
Assesses the relative contributions of genetics and environmental influences on intelligence and personality. Jensen intelligence 80% genetic. Burt. Eysenck.
Twin studies - Bouchard and McGue (1981) review showed identical twins more similar to each other (than fraternals) on both extraversion and neuroticism on 3 major studies, e.g. Heath et al., 1989), e.g. MZ together .86: MZ apart .72: siblings .47.
Assumes ‘equal environments’ when MZ and DZ raised together, and ‘different’ environment when separated.
identical twins more concordant for autism, e.g. Folstein and Rutter (1977)
with types of troubles, problems, even divorce risk, higher similarity between identical twins, e.g. McGue and Lykken (1992).
Twins reared apart rare, but examples from separated identical twins who choose the same vocation (e.g. Bouchard, 1981), type of partner, habits.
Adopted children whose personality does not resemble that of adoptive parent.
Zajonc and Markus (1975) - IQ decline with birth order and family size
Skeels (1966) - IQ up when institutionalised children go to enriching environment.
Neuropsychological/Cognitive Bias and its Modification
Possible gender bias in Emotional Competent (Lawrie, 2013)
Right Brain Dominance in Creatives
Possible modification through:-
Neuroplasticity
Mindfulness
Brain Training
Therapeutic Techniques
Different perspectives try to explain the reasons (aetiology) for our behaviour. Therapies used to treat mental illness dependent on the perspective taken.
The Biological Perspective, concerned with overactivity of chemical neurotransmitters (e.g. dopamine in schizophrenia), genetic, or organic (neurological) causes, as described above, will use Biological (Somatic) Therapies.
The Behaviourist Perspective, concerned with environmental influences on personality development and the role of learning, will use Behaviour Therapies, based on unlearning and learning anew.
Other perspectives – the Psychoanalytic, Humanistic and Cognitive have their own therapies.
Together with the Behavior Therapies these are truly ‘psychotherapies’, unlike those using biological treatments.
Psychosurgery:
prefrontal lobotomy (tissue destroyed between frontal lobes and thalamus), but now more specific areas.
Electroconvulsive therapy (ECT
convulsions increase noradrenalin in depressives.
Drug therapy:-
for anxiety (e.g. tranquillisers such as Valium and Librium) to depress CNS
- for depression (e.g. stimulants such as Prozac) which block serotonin but not noradrenalin in depressives
- antipsychotic drugs (e.g. phenothiazines and Clozapine which reduce dopamine activity in schizophrenics) and
- antimanic (e.g. Lithium, which moderates noradrenalin).
