Biological perspective
Historical and cultural conditions that
gave rise to the biological perspective
Dualism
Darwin
Scientific 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 al
 Vogel and Bogen
(1961)

anterior cerebral
commissurotomy
Hemispheric specialization
chimeric figures
 Focus on the dot
 Point: pick a woman
 Talk: pick a man
 EEG
 MRI
 PET
 http://hendrix.ei.dtu.d
k/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
Physiological
Cultural
Emotional
Female/male differences (1 to 7)
Feel fat vs are fat
Weight 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
 Nurture
 2. Influence of learning.
behavioral capacity for
aggression.
 PhysiologicalControl of
aggression by brain,
blood and hormones.
 Organism 1. Why
animals aggress. Control
by genetic and
physiological factors.
a. Pavlovian conditioning
b. Operant conditioning
c. 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 supply
c. 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 Gland
The 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 Glands
Within 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 1220%
 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
 Add a female
 an average of 2.6 times,
 Female rats did not
attack other rats, and
and
 received an average of 1.8
scars
 Guess what:
 significantly lower levels
of dopamine and
serotonin in areas of the
amygdala
 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
girl
 15 years he was
abused
 15 years lived
normal (but with
fantasies)
 Then car accident
The mind of a killer: Application
 Hitler
 Abused as a child
 Manic 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