biological perspective. historical and cultural conditions that gave rise to the biological...
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Biological perspective
Historical and cultural conditions that
gave rise to the biological perspective
DualismDarwinScientific studies
Contribution of the biological perspective to the scientific study of behaviour, and its current
standing
biological correlates of behaviour genetic contributions to
explanations of behaviour effects of hormonal change on
behaviour experimental testing of hypotheses use of both quantitative and qualitative
research
Key concepts
how physiological concepts such as the endocrine system, central nervous system affect behaviour
neurotransmitters—excitatory, inhibitory
the brain—localization of function bodily rhythms
Resting potential
Action potential
Split brain
Sperry et alVogel and Bogen
(1961)
anterior cerebral commissurotomy
Hemispheric specialization
chimeric figures
Focus on the dotPoint: pick a womanTalk: pick a man
EEG
MRI
PET
http://hendrix.ei.dtu.dk/movies/moviehome.html
Migrane
Evaluation of assumptions
use of alternative perspectives as a possible evaluative strategy
Ponzo illusion
Which red bar is longer?
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The moon illusion
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Muller-Lyer illusion
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You see whom you wish to see
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Theoretical explanations of behavioural change
use of drugs; surgical procedures psychological correlates of physiological
processes, such as emotion, anorexia nervosa and bulimia nervosa
Eating disorders
PhysiologicalCulturalEmotionalFemale/male differences (1 to 7)Feel fat vs are fatWeight vs shape
"But it probably involves a transition from psychosocial to biomedical mechanisms."
Methods
correlational studies double-blind trials experiments interviews case studies questionnaires
Strengths and limitations of methods
comparison of invasive and non-invasive techniques
Ethics and controversies of research
use of human and non-human animals for research
Effectiveness of the perspective in explaining psychological and/or social
questions comparison with other perspectives on
questions such as aggression, gender differences or stress
application of genetic research and its ethical implications
Gender differences: Nature or nurture?
•Females have evolved mechanisms that enable them to detect men that will transfer resources to their offspring (i.e. health and paternal investment ). These are sometimes referred to as 'good provider' and 'good genes' attributes in the male •Males have evolved mechanisms that enable them to detect females that promise rapid production of offspring, and a disinclination to mate with other men (i.e. health, fertility and faithfulness )
Aggression
Nature Nurture
Aggression
Nature GeneticInheritance of
behavioral capacity for aggression.
PhysiologicalControl of aggression by brain, blood and hormones.
Organism 1. Why animals aggress. Control by genetic and physiological factors.
Nurture 2. Influence of learning.
a. Pavlovian conditioningb. Operant conditioningc. Social modeling
SocietySocietal organization, cultural and political determinants of aggression
a. Sociology b. Anthropology c. Political Science
Aggression
Nature GeneticInheritance of
behavioral capacity for aggression.
PhysiologicalControl of aggression by brain, blood and hormones.
Organism 1. Why animals aggress. Control by genetic and physiological factors.
Nurture Ecology Large scale population
characteristics and availability of natural resources.
a. Over population (e.g., Rwanda)
b. Limited food supplyc. Limited energy supply 1. Oil exhausted by the year
2050
Lorenz' Hydraulic Model of motivation
Hydraulic Theory predicts: Aggression is inevitable - the
accumulating energy must find an outlet
Humans & animals will actively 'look for fights'.
After an attack an animal / human will become less aggressive.
Animals reared in isolation will show aggressive behaviour.
Baerends and his guppies
HUMANS AIN’t Guppies!Or are they?
Does the Hydraulic model explain this?
Deutsch's Model of motivation
Notice the feedback loop!
Phineas Gage
Railroad worker-spike went through his head:Gage was able to walk away from the accident,
"talking with composure and equanimity of the hole in his head."
Previously a polite and sociable gentleman, Gage became an antisocial, foul-mouthed, irresponsible, bad-mannered lout and unrepentant liar.
According to his friends, he was "no longer Gage." He drifted from job to job, finally dying penniless.
Jonathan Toot and his wandering rats
Add a male Add a female
THE ENDOCRINE SYSTEM
The endocrine system—the other communication system in the body—is made up of endocrine glands that produce hormones, chemical substances released into the bloodstream to guide such processes as metabolism, growth, and sexual development. Hormones are also involved in regulating emotional life.
THE ENDOCRINE SYSTEM
The Thyroid GlandThe thyroid gland secretes thyroxin, a hormone that can reduce concentration and lead to irritability when the thyroid is overactive, and cause drowsiness and a sluggish metabolism when the thyroid is underactive.
The Parathyroid GlandsWithin the thyroid are four tiny pea-shaped organs, the parathyroids, that secrete parathormone to control and balance the levels of calcium and phosphate in the blood and tissue fluids. This, in turn, affects the excitability of the nervous system.
THE ENDOCRINE SYSTEM
The Pineal Gland The pineal gland is a pea-sized gland that apparently responds to exposure to light and regulates activity levels over the course of the day.
The Pancreas The pancreas lies in a curve between the stomach and the small intestine and controls the level of sugar in the blood by secreting insulin and glucagon.
THE ENDOCRINE SYSTEM
The Gonads These reproductive glands—the testes in males and the ovaries in females, and, to a lesser extent, the adrenal glands—secrete androgens (including testosterone) and estrogens.
THE ENDOCRINE SYSTEM
The Adrenal Glands The two adrenal glands are located above the kidneys. Each has two parts: an outer covering, the adrenal cortex, and an inner core, the adrenal medulla. Both influence the body's responses to stress. For example, in response to a stressful situation, the pituitary gland may release beta endorphin and ACTH, which, in turn, prompt the adrenal cortex to release hormones. Meanwhile, the autonomic nervous system stimulates the adrenal medulla to secrete hormones such as epinephrine into the bloodstream.
Brain size
Brain size
At birth, the average brain of boys is between 12-20%
However, when the size of the brain is compared to body weight at this age, there is almost no difference between boys and girls
Many recent claims have been made that the corpus callosum is bigger and more developed in women than in men.
Brain size
Preoptic Area of the Hypothalamus 2.2 times the size in boys after 4 years of age
studies show that human male brains are, on average, approximately 10 percent larger than female brains. Certain brain areas in women, however, contain more nerve cells.
Normal Synapse
Effect of MDMA at Synapse
MDMA can cause the release of the neurotransmitter called serotonin.
MDMA can block the reuptake of serotonin by the synaptic terminal that releases it.
MDMA can deplete the amount of serotonin in the brain.
MDMA can cause an indirect decrease in the amount of the neurotransmitter called dopamine.
Your brain on cocaine
Cocaine acts by blocking the reuptake of the neurotransmitters dopamine, norepinephrine and serotonin in
Brain during sleep
Jonathan Toot and his wandering rats
Add a male an average of 2.6 times,
and received an average of
1.8 scars Guess what: significantly lower levels
of dopamine and serotonin in areas of the amygdala
Add a femaleFemale rats did not
attack other rats, and were not attacked
themselves.
Jonathan Toot and his wandering rats
"The data show that males are involved in more fights than females," they say, "suggesting increased aggression is influenced by a Y-chromosomal effect that decreases amygdala serotonin."
The researchers speculate that testosterone levels also contribute to males' increased aggression.
open up the possibility of being able to identify the chromosome markers in high-risk males, and of trying to manipulate their levels of serotonin, through diet, exercise, or medication.a long way down the road, but this is the start."
More mice
"The effect of ginkgo biloba on aggression was remarkable," the researchers say. "When 0.1 ml of ginkgo biloba was administered to MAOA knockout mice, their aggressive behavior in resident-intruder confrontations was reduced significantly." The substance had no effect on the mice's nonsocial, investigative, defensive, or movement behaviors, indicating that effects were not due simply to sedation.
Ruben Gur and colleagues performed MRI
57 men and 59 women
•The researchers measured
•the volume of the amygdala,
•hippocampus, and
•other limbic areas associated with emotional arousal,
•as compared to the volume of orbital frontal brain regions that exert control over emotional responses
Ruben Gur and colleagues performed MRI
57 men and 59 women
•Results:
•Same for:
•the volume of the amygdala,
•hippocampus, and
•other limbic areas associated with emotional arousal,
•But women had significantly larger orbital frontal cortex volume than men.
Ruben Gur and colleagues performed MRI
Conclusions: "Because men and women differ in the way they
process the emotions associated with perception, experience, expression, and most particularly in aggression," the researchers say, "our belief is that the proportional difference in size in the region of the brain that governs behavior, compared to the region related to impulsiveness, may be a major factor in determining what is often considered 'gender-related' behavior."
There is little doubt that social and psychological factors contribute to the development of crime, and there is an extensive body of research established in those areas. Could there also be, however, a biologic risk for wickedness, whereby an individual is biologically predisposed to engage in serious repeat criminal offenses? There is a growing body of literature to suggest that this may be the case. In other words, biological individual differences may be a predisposition to crime."Angela Scarpa and Adrian Raine,"Biology of wickedness,"in Psychiatric Annals,September 1997
The mind of a killer
mental illness, neurological damage and child abuse.
The mind of a killer
It's pretty clear that mental illness is not enough to cause violence because most people who are mentally ill are not violent
The mind of a killer
It's also evident that neurological damage is not enough to cause violence because the vast majority of people who are neurologically impaired are not violent.
The mind of a killer
And it's clear that the experience of horrendous child abuse is not enough to cause violence because most people who are abused that way are not violent.
The mind of a killer
Yet, most violent people have these three factors, or two of the three.
The mind of a killer: Theory
abuse sets up an impulse toward violence that a good brain can control.
neurological damage and mental illness, then violent impulses are not easy to check.
The mind of a killer: Application
Lewis Culpepper Sexually abused a
girl15 years he was
abused15 years lived
normal (but with fantasies)
Then car accident
The mind of a killer: Application
HitlerAbused as a childManic depressive,
filled with anger
The conclusion of this paper is a wholehearted rejection of any consideration of biological, genetic, or evolutionary factors in the explanation or analysis of conflict. While a number of different arguments are presented, and it is admitted in some cases that the outcome is not conclusive, the net consequence of these arguments is in favour of the rejection of biology and the acceptance of social explanations based on human openness and what have been described as the essential features of man. But this has been said before: the proper study of man is man.
Keith Webb
But we can, perhaps, go further than this. The biological interpretation of the world is not just a description of the world, but like all social theory has prescriptions embedded within it. These prescriptions are profoundly reactionary and operate to justify the existing social order. Thus Shaw and Wong (1989: 195-209) attack 'top-down' and 'bottom-up' approaches to peace, as well as functional or world society approaches (e.g., Banks, 1984) as approaches which do not recognise the essential nature of man.
Keith Webb
Their own scheme for peace is no more convincing than that of Lorenz before them - educational efforts, a redefinition of inclusive fitness, and a voluntaristic change in attitudes and beliefs. But, in terms of their own theory, such hopes are utopian; rather, they should accept the dismal consequences of their own ideas and recognise that peace is unattainable. The real message of biological arguments is that the human race will forever be embroiled in violent confrontations and thus arms races, nuclear deterrence, balances of power, and military alliances, are the best means of attaining our security.
Keith Webb
Given the weakness of biological arguments, however, there is no need to accept these conclusions, and hence no good reason to succumb to a mindless fatalism.
So what are the limitations of biologic psychiatry?
First of all, medications lessen symptoms, they do not treat mental illness per se. This distinction is crucial. Symptoms by definition are the surface presentation of a deeper process. This is self-evident. However, there has been a vast and largely unacknowledged effort on the part of modern (i.e., biologic) psychiatry to equate symptoms with mental illness.
Recommendations for change in lifestyles
contribution of the biological perspective to changes in education, work or therapy
Assumptions on which key concepts are based
innate disposition and environmental influences and their evaluation
imprinting relative influence of inherited and
environmental factors upon behaviour, such as intelligence
http://psych.hanover.edu/Krantz/tutor.html#Biopsychology/Physiopsychology
There are three different aspects to biology to consider: biology is the causation of behavior, genetics, and evolution.
One way of studying the brain is through clinical observation - looking for specific areas of the brain that are damaged and then determining the functions of that damaged area of the brain based on the behavioral response.
Recent advances in technology has yield better ways of studying the brain through neuroimaging (eg. through MRI and CAT scans, for example).
Among the various structures in the brain, the cortex is probably the most important as it controls motor, sensory and higher mental functions such as thought, language, reason, emotion and memory.
A neuron is the specialized cell of the nervous system. Neurons communicate via neurotransmitters, which are special
chemicals that are released at the synapse. The endocrine system is a complementary system to the nervous
system in that it has a role in determining behavior as well.