biological Flashcards
explain the process of synaptic transmission
action potential reaches the terminal button
vesicles release neurotransmitters into the synaptic cleft
neurotransmitter binds to the receptors on the post synaptic neuron
neurotransmitters that don’t attach enter the presynaptic neuron via reuptake channels
evaluate evolution as an explanation of human behaviour
S. gender differences. males who are aggressive are more likely to be naturally selected because they make better hunters. supported by mason + wrangham
O. correlation. impossible to directly test evolution. can’t draw cause and effect conclusions because variables just measured not manipulated
D. hormones
A. Buss- males preferred younger, more attractive, chaste women. females preferred ambitious, wealthier men
explain Freuds psychodynamic theory
id- driven by the pleasure principle. functions in the unconscious and made up of aggressive instances that demand immediate gratification
ego- reality check that balances the conflicting demands of the id and super ego
super ego- moralistic part of personality that represents the ideal self/ how we ought to be
evaluate Freuds psychodynamic theory as an explanation of aggression
S. hot blooded and cold blooded aggression. hot- impulsive and angry caused by id, failure of egos normal function of reducing id’s agressive impulses. cold- deliberate and rational- outcome of egos successful control of id impulses
O. bushman- made college students angry by getting a confederate to criticise an essay each had written. one group was allowed to vent anger. these students blasted the confederate with the loudest and longest noises compared to control group
D. evolutionary theory
A. catharsis used in therapy- bringing unconscious and forgotten memories into the conscious mind
evaluate hormones as an explanation for aggression
S. dabbs- measured testosterone levels in female inmates. degree of violence was positively corrlelated with testosterone level. seen as ‘tough’ by other inmates
O. testosterone fluctuates from one encounter to another. baseline measure is used in many studies but everyone has a different baseline. lacks validity
D. evolutionary explination of aggression
A. development of drugs. depo-provera (testosterone lowering drug) reduced levels of sexually aggressive behaviour in some offenders
rains findings
lower levels in left side of amygdala
higher in right side of amygdala
lower activity in prefrontal cortex
rains procedure
41 NGRI’s, 41 controls matched for age, sex and ethnicity
ppts injected with radioactive tracer
completed tasks- identifying targets on a screen and pressing a button
Pet scan conducted immediately after 32 minute period
scan took 10 images at 10 millimetre intervals
rain evaluation
+ validity- matched on age, gender, ethnicity
+ reliability- standardised procedure
- validity- canthomeatal line
- ethics- uneccesary medical procedure for controls- exposed to radiation
brendegen procedure
- 234 pairs of twins from the quebec newborn twin study at age 6
- teacher ratings- rated children’s aggression on a 3 point scale (never, sometimes, often) in response to statements such as ‘hits, kicks or bites others’
- peer ratings- children circled 3 classmates faces in a booklet that best matched the description’s e.g.’ tells mean secrets about another child’
brendegen findings
20-23% of social agression was explained by genetic factors
physical agression was mostly explained by heritable factors
statistical tests showed high physical agression led to high social agression
evaluate brendegens study
+ interventions to reduce aggression. future studies could identify the factors that block the path from physical to social agression
+ standadised procedure- peer ratings- children all given same booket of classmates faces, all given the same point to mark againsed, all told to circle 3
- ethics- getting children to vote which child in their class most likely to tell mean secrets may break up friendships/ lead to bullying and cause the children to be treated differently after the study.
- validity- teachers used their memories of the twins in order to rate them on a scale. This makes the results susceptible to error because memory is unreliable.
how does cocain affect the synapses
blocks the reuptake of dopamine by binding to dopamine transporter moelcules on the pre synaptic neuron
the synaps is flooded with surplus quantaties of dopamine all available for binding with post synaptic receptors
this causes a euphoric high
what are the effects of repeated cocain use
dopamine receptors become downgraded so fewer receptors are activated (some are damaged and some shut down)
quantities of dopamine produced declines
causing higher doses needed to get the same effect
the effect of heroin on synapses
injected and converted into morphine
morphine binds with a specific oplid receptor at the synaps
endorphins are produced as natural pain killers
what are the long term effects of heroin
Downregulation
Overtime oploid receptors are constantly binding with morphine which desensitizes them to the effect of the drug
