AQA Psychology Revision – Topic Summary Hormonal Mechanisms
Paper 3 (option topic) – Aggression Serotonin - high levels reduce aggression,
inhibits neurons in amygdala
Aggression – innate, behaviour that is
threatening or intends to harm others Testosterone - high levels increase
aggression, adrenal glands and sex glands,
Neural and Hormonal Mechanisms
men produce more
Neural Mechanisms
The limbic system – associated with
Research: Crockett 2013
emotional processing: formix, cingulate
gyrus, thalamus, hippocampus, - Pps drugs increase serotonin less
hypothalamus and amygdala agg when opponent split money
unfairly between
Hypothalamus – involved in activating the
- Pps drugs decreased serotonin more
sympathetic nervous system, triggering the
agg
fight or flight response and thus aggression
Research: Dabbs et al 1995
Hippocampus – responsible for memory,
sends information stored in our memory to - Positive correlation between
the amygdala testosterone levels and violence in
prison inmates
Amygdala – attaches emotional significance
- BUT correlational + environment
to sensory information, emotional
importance Evaluation
The frontal cortex - Support Crockett et al + Dabbs et al
- Not shown association testosterone
- If aggression inappropriate frontal
not replicated so not reliable
cortex signals amygdala inhibit
- Most research into testosterone only
neurons cause neurons generate
uses male participants
fewer nerve impulses = stops send
signal hypothalamus Evaluation of Neural + Hormonal
- Damage = aggressive behaviour Mechanisms:
Research: Sumer et al 2007 – supports - Ignore non-biological factors
amygdala
Genetic Explanations
- 14 year old girl with excessive
- Different gene alleles make people
aggression had tumour pressing on
more or less aggressively, many
amygdala increasing amygdala
genes involved
activity
MAOA gene
Research: Mpakopoulou 2008 – supports
amygdala - Make chemical controls amount
(serotonin) neurotransmitters
- Review 13 studies patients with
available synapse
seizures who had amygdalotomy,
- Two alleles, short more aggressive,
after surgery aggression reduced
long less
between 33%-100%
Research: Christiansen 1977
Evaluation
- Twin study: MZ 55% concordance
- Support Sumer et al
rate criminal behaviour DZ 22%
- Support MPakopoulou
- Sumer et al case study so not Research: Hutchings and Mednick 1975
generalisable
- Inconsistency – some found damage - Adoption study: children display
= decrease aggression others criminal behaviour more likely bio
increase parents criminal
, Research: Brunner 1993 – supports MAOA - Ignores environmental: Prinz argue
differences caused by social norms
- Case study: DNA analysis 5 Dutch
- Alpha gender bias: men are all
men same family excessive
aggressive and jealous – Prinz argue
aggression, mutation MAOA, impair
girls are agg just mor verbally than
serotonin metabolism
psychically
Evaluation - Implications on society: ethical issues
- Assume environmental impact same Ethological Explanations (part of
MZ DZ BUT MZ often share more evolutionary)
similarities
Ethology – the study of animal behaviour
- Adoption: often match families
similar bio, similar environment to - Aggression has evolved through
would have with bio natural selection because it is
- Gene environment interacts adaptive
diathesis-stress: Caspi et al children - Assumes understand agg humans
short allele more likely aggressive looking at other animal species in
adults but depend environment only natural habitat
maltreated aggressive
Lorenz – aggression is ‘fighting instinct in
Evolutionary Explanations beats and man which is directed against
members of the same species’
- Aggression = an adaptive behaviour
- Prehistoric age help survive and Ritualistic – aggression is used to threaten
reproduce other members of the species without
- Through natural selection we’ve harming the
evolved to display aggression
Ritualistic signals – threat displays,
Aggression was adaptive for men because: appeasement gestures
- Help gain access to resources and - Aggression is a fixed action pattern
mates (FAP) – innate, fixed set of
- Help gain respect and dominance behaviours occur in response to
- Help prevent infidelity through specific sign stimuli
threatening other cavemen - The neurons involved in causing FAP
called Innate releasing mechanism
For women:
(IRM) sensory, relay and motor
- Cavewomen no competition neurons
reproductive partners so women not
Research: Tinbergen 1951
evolved aggressive
- Instead worry keep babies alive so - Male stickleback fish, displayed same
select aggressive partners to protect fixed set of aggressive behaviours
- Less scared of infidelity instead when they observed something look
worry abandon because leave male, red belly
unprotected
Evaluation
Research: Buss et al 1992
- Aggression not always ritualistic:
- Questionnaire: if men and women Goodall 2010 found chimpanzees will
more upset sexual or emotional fight and kill others form
infidelity neighbouring groups – since can get
- Sexual: men 51% upset women 22% injured in fights not adaptive
- So jealousy cause males aggressive - Cultural variation: Nisbett 1996
- Argue differences cause studied agg US, found south more
genetics/evolution prone than north
- BUT questionnaire + hypothetical - Animal studies not generalisable
Evaluation Social Explanations
Paper 3 (option topic) – Aggression Serotonin - high levels reduce aggression,
inhibits neurons in amygdala
Aggression – innate, behaviour that is
threatening or intends to harm others Testosterone - high levels increase
aggression, adrenal glands and sex glands,
Neural and Hormonal Mechanisms
men produce more
Neural Mechanisms
The limbic system – associated with
Research: Crockett 2013
emotional processing: formix, cingulate
gyrus, thalamus, hippocampus, - Pps drugs increase serotonin less
hypothalamus and amygdala agg when opponent split money
unfairly between
Hypothalamus – involved in activating the
- Pps drugs decreased serotonin more
sympathetic nervous system, triggering the
agg
fight or flight response and thus aggression
Research: Dabbs et al 1995
Hippocampus – responsible for memory,
sends information stored in our memory to - Positive correlation between
the amygdala testosterone levels and violence in
prison inmates
Amygdala – attaches emotional significance
- BUT correlational + environment
to sensory information, emotional
importance Evaluation
The frontal cortex - Support Crockett et al + Dabbs et al
- Not shown association testosterone
- If aggression inappropriate frontal
not replicated so not reliable
cortex signals amygdala inhibit
- Most research into testosterone only
neurons cause neurons generate
uses male participants
fewer nerve impulses = stops send
signal hypothalamus Evaluation of Neural + Hormonal
- Damage = aggressive behaviour Mechanisms:
Research: Sumer et al 2007 – supports - Ignore non-biological factors
amygdala
Genetic Explanations
- 14 year old girl with excessive
- Different gene alleles make people
aggression had tumour pressing on
more or less aggressively, many
amygdala increasing amygdala
genes involved
activity
MAOA gene
Research: Mpakopoulou 2008 – supports
amygdala - Make chemical controls amount
(serotonin) neurotransmitters
- Review 13 studies patients with
available synapse
seizures who had amygdalotomy,
- Two alleles, short more aggressive,
after surgery aggression reduced
long less
between 33%-100%
Research: Christiansen 1977
Evaluation
- Twin study: MZ 55% concordance
- Support Sumer et al
rate criminal behaviour DZ 22%
- Support MPakopoulou
- Sumer et al case study so not Research: Hutchings and Mednick 1975
generalisable
- Inconsistency – some found damage - Adoption study: children display
= decrease aggression others criminal behaviour more likely bio
increase parents criminal
, Research: Brunner 1993 – supports MAOA - Ignores environmental: Prinz argue
differences caused by social norms
- Case study: DNA analysis 5 Dutch
- Alpha gender bias: men are all
men same family excessive
aggressive and jealous – Prinz argue
aggression, mutation MAOA, impair
girls are agg just mor verbally than
serotonin metabolism
psychically
Evaluation - Implications on society: ethical issues
- Assume environmental impact same Ethological Explanations (part of
MZ DZ BUT MZ often share more evolutionary)
similarities
Ethology – the study of animal behaviour
- Adoption: often match families
similar bio, similar environment to - Aggression has evolved through
would have with bio natural selection because it is
- Gene environment interacts adaptive
diathesis-stress: Caspi et al children - Assumes understand agg humans
short allele more likely aggressive looking at other animal species in
adults but depend environment only natural habitat
maltreated aggressive
Lorenz – aggression is ‘fighting instinct in
Evolutionary Explanations beats and man which is directed against
members of the same species’
- Aggression = an adaptive behaviour
- Prehistoric age help survive and Ritualistic – aggression is used to threaten
reproduce other members of the species without
- Through natural selection we’ve harming the
evolved to display aggression
Ritualistic signals – threat displays,
Aggression was adaptive for men because: appeasement gestures
- Help gain access to resources and - Aggression is a fixed action pattern
mates (FAP) – innate, fixed set of
- Help gain respect and dominance behaviours occur in response to
- Help prevent infidelity through specific sign stimuli
threatening other cavemen - The neurons involved in causing FAP
called Innate releasing mechanism
For women:
(IRM) sensory, relay and motor
- Cavewomen no competition neurons
reproductive partners so women not
Research: Tinbergen 1951
evolved aggressive
- Instead worry keep babies alive so - Male stickleback fish, displayed same
select aggressive partners to protect fixed set of aggressive behaviours
- Less scared of infidelity instead when they observed something look
worry abandon because leave male, red belly
unprotected
Evaluation
Research: Buss et al 1992
- Aggression not always ritualistic:
- Questionnaire: if men and women Goodall 2010 found chimpanzees will
more upset sexual or emotional fight and kill others form
infidelity neighbouring groups – since can get
- Sexual: men 51% upset women 22% injured in fights not adaptive
- So jealousy cause males aggressive - Cultural variation: Nisbett 1996
- Argue differences cause studied agg US, found south more
genetics/evolution prone than north
- BUT questionnaire + hypothetical - Animal studies not generalisable
Evaluation Social Explanations
