Biological Psychology Flashcards
What brain functions are localised to the frontal lobe?
- problem solving (PFC)
- producing speech (Brocas area)
- muscle movement (motor strip)
What brain functions are localised to the parietal lobe?
- senses (sensory strip)
What brain functions are localised to the temporal lobe?
- memory
- language understanding it (Wernickes area)
What brain functions are localised to the occipital lobe?
- vision
- visual cortex
What is the difference between Brocas Aphasia and Wernickes aphasia?
Broca = unable to speak but can still undertsnad language Wenicke = unable to understand language but can make speech sounds
What is localisation of function?
where each part of the brain is responsible a specific different job
- If a certain area of the brain becomes damaged, the function associated with that area will also be affected.
What is cross lateralisation?
where the brain corresponds with the opposite side of the body
Name the three types of brain scan
PET
CAT/CT
fMRI
What is temporal resolution?
how well the scanner tracks changes in brain activity
What is the temporal resolution of a fMRI scan?
20 seconds, it has the highest temporal resolution
What is the temporal resolution of a PET scan?
5 - 15 minutes, it has a lower temporal resolution than an fMRI scan
What is voxel size?
smaller voxel size means there is more detail so the scan has a higher spatial resolution
What is spatial resolution?
how fine the detail on a scan is
Rank the 3 scans spatial resolution from highest to lowest
CAT/CT = highest spatial resolution fMRI = high spatial resolution but lower than a CAT scan PET = lowest spatial resolution
What is the voxel size of a CAT/CT scan?
0.5mm
What is the voxel size of a fMRI scan?
1.5mm
What is the voxel size of a PET scan?
6mm
Describe a CAT/CT scan
produces a detailed image of brain structure uses x rays quickest scan = 5 mins not too susceptible to motion artefacts cheap £100-400
Describe a PET scan
positron emission tomography mainly shows brain activity works by detecting radioactive tracers that are injected into the person very expensive low temporal resolution 5-15mins lowest spatial resolution scan is in colour
Describe a fMRI scan
scan shows detail of both brain activity and structure
good spatial resolution
high temporal resolution 20 seconds
really long 30-40 mins
not suitable for someone with a pacemaker or metal
very susceptible to motion artefacts
What is the cost of each scan?
CAT/CT cheapest = £100 - £400
fMRI= £200 - £500
PET expensive= £500 per scan, cost of the tracer
Describe the structure of a neuron
- list the parts
- dendrites
- soma
- cytoplasm
- nucleus
- myelin sheath
- nodes of ranvier
- axon
- terminal
check folder for a diagram
Explain how an action potential is transmitted
- at rest = neural membrane is positive outside and negative inside
- the dendrites are disturbed by neurotransmitters and depolarisation occurs as neural membrane opens and negative charges move in
- this prompts a chain reaction and depolarisation occurs down the axon passing the signal down the dendrites to terminals.
What is the action of an inhibitory synapse?
if the inhibitory neuron action potential frequency increases the other neurons frequency will decrease (it does the opposite).
What is the action of an excitatory synapse?
both act the same e.g. both decrease or both increase
What is a neurotransmitter?
- a chemical messenger that acts between 2 neurons,
- specific neurotransmitters have specific and different affects
What is a synapse?
- a junction between 2 neurons, dendrites to terminals
What is synaptic transmission?
- action potential prompts vesicles to release neurotransmitters at the terminal into the synapse
- neurotransmitters diffuse across the synaptic gap
- receptors at the postsynaptic neuron binds to neurotransmitter and increase the probability of an action potential
How do we regulate the amount of neurotransmitter in the synaptic gap?
- enzymes breakdown excess neurotransmitters
- reuptake proteins are used to move excess neurotransmitters from the synaptic gap to the presynaptic neuron
What are psychoactive drugs?
- drugs that change brain functioning, cognition, emotion and behaviour
What is tolerance?
- it is when the brain becomes used to the effect of the drug so more drug is needed to stimulate the same effect
What is dependence?
- dependence is when a user is unable to fully function unless they take the drug
What is the reward pathway?
- the drug leads to pleasure, the want to achieve this effect again and gain the reward leads to addiction.
How does nicotine affect synaptic transmission and the nervous system?
- it causes more neurotransmitter to be released in response to an impulse
- this affects the reward pathway
How does cocaine affect synaptic transmission and the nervous system?
it is a REUPTAKE INHIBITOR
- cocaine latches on to reuptake mechanism for dopamine
- more dopamine is released into the synapse (agonist)
- it is a stimulant and activates the reward pathway, feel more alert, better mood and confident
How does heroin (opiods) affect synaptic transmission and the nervous system?
- morphine binds to receptors for endorphine acting as endorphine (endorphine analogue)
- endorphine levels increase
- GABA levels decrease
- dopamine level increase
- this activates the reward pathway so you feel no pain, sedative, fell dreamy, euphoric and drowsy
How do cannabinoids affect synaptic transmission and the nervous system?
- anandamide acts as a GABA regulator by binding to GABA receptors
- delta A THC is the analogues of anandamide and so it acts as anandamide and binds to and stimulates the anandamide receptors
- GABA levels decrease
- dopamine levels increase
- feel sedated, deeper senses, more relaxed, hungry
In detail describe the steps of synaptic transmission
- action potentials arrive at the terminals
- vesicles release neurotransmitters
- increased concentration of neurotransmitter in ths synaptic gao
- increased probability that neurotransmitters bind to receptors
- change in probability of action potential of post synaptic neuron
- reuptake and enzymes break down neurotransmitter
What are the 4 drug mechanisms?
block enzyme activity
block reuptake
block receptor
activate receptor
What are the key ideas of evolution?
explanation of the ways characteristics if an organism change overtime
- role of genes
- descent with modification (variation as each generation is different from the one before)
- EEA environment of evolutionary adaptation
- features of the environment exert selection pressures
What is natural selection?
A theory of evolution, depends on the environment some traits are more useful than others in certain environments as the environment provides a selection pressure.
How can natural selection and evolution be used to explain aggression?
- Aggression is affected by inherited genes (mutation form assortative mating)
- the EEA exerts selection pressures where having the aggressive genes is advantageous and favoured by the selection pressure
- those with the aggressive genes are more likely to survive and reproduce, passing on their aggressive genes to future offspring
What are the strengths of the evolutionary theory of aggression?
- aggression is universal and uniquely high in humans
- aggression increases during scarcity (correlation)
- aggression brain areas/structures are common to many species
What are the weaknesses of the evolutionary theory of aggression?
- evidence is correlational not causation
- aggression could also be learned (Bandura, 1963)
- not possible to directly test as it occurs over many years
Evidence to support evolutionary theory of aggression
Buss (2000)
men care about infidelity more than women
Putz et al (2016)
male figure is bigger than female which supports more male vs male competition for mates
Evidence to reject evolutionary theory of aggression
Bandura et al. (1963)
showed aggression is environmental not biological
Lorenz (1966)
species become more aggressive following scarce resources so its a learnt feature
Allen et al. (2016)
found a correlation between environment and violent death
what two types of studies can be used to investigate genetics and aggression
twin studies
adoption studies
Adoption study example KETY ET AL. (1968)
did a study of 34 schizophrenia patients that had been adopted and compared them to 33 control mentally healthy adoptees
-4 danish psychiatrists did blind tests to diagnose family members based on medical records
- B1 = chronic
- B2 = acute
- B3 = borderline
biological parents had a higher correlation than adopttive parents
biological relatives of probands had a correlation of 8.7% compared to relatives controls of 1.9%
shows there is a high genetic influence on sz
Which 3 brain structure affect aggression?
- hypothalamus
- amygdala
- pre frontal cortex
How does the Pre Frontal Cortex impact aggression?
damaged, low activity or low volume PFC = issues with inhibiting aggressive impulses
- person acts in an aggressive manner because they can’t stop themselves as impulse control is damaged they also won’t learn from punishment
What is the role of PFC in aggression?
- to act as impulse control and exercise inhibitory control
What is the role of the amygdala in aggression?
- to interpret information from the environment and decide if it is a threat or provocation (challenge), respond to these challenges with aggressive impulses
How does the amygdala impact aggression?
- overactive amygdala = more sensitive to threats (perceive more threats) respond with aggression
- underactive amygdala = won’t detect fear from others or experience it themselves so they may persist with aggression
- diminished fear response
- difficulty in distinguishing emotions
What is the role of the hypothalamus in aggression?
- predatory aggression
- allows amygdala to draw on past memories and experiences to determine if something is a challenge
How does the hypothalamus impact aggression?
- active hypothalamus = stimulates predatory aggression so person acts more aggressive
Evidence to support role of PFC in aggression.
DE BRUIN ET AL. 1983
- damage to parts if the PFC can facilitate aggressive responses
Evidence to support role of amygdala in aggression.
PINEL ET AL 1977
MICZEK ET AL 1974
- damage to amygdala in monkeys can either inhibit or dis inhibit aggressive behaviour, depending on the site of the damage
Evidence to support role of the hypothalamus in aggression.
FUCH ET AL 1985
KRUK 1991
- electrical stimulation of hypothalamus of cats and rats causes social or predatory aggression depending on where stimulation is applied
CASE STUDY for aggression
- charles J whittman 1966
murdered mother, wife and fourteen strangers ( shooting at the top of the University of Texas tower
- post mortem = tumour that affected his hypothalamus and amygdala
- diary LAVERGNE 1997 = accounts of unpredictable inexplicable rage before shooting which he had sought medical treatment for
What is a hormone?
- a chemical messenger secreted by glands in the endocrine system that is carried around the body in the blood
- affect a wide range of behavioural and physiological functions
What is the organising effect?
- effect the hormone has on influencing organ structure
What is the activation effect?
- effect a hormone has on influencing organ function
How do hormones work?
bind to receptor proteins on the target cell and change the cell function
Which hormone is linked to aggression?
Testosterone
How does testosterone affect aggression levels
- organising affect on the brain
- testosterone levels are higher in males than in females so an affect the way brain structures (hypothalamus and amygdala) develop in male and female embryos - activating effect
- the testosterone hormone acts as a neurotransmitter and can increase or decrease activity in different brain areas
e. g.
- testosterone increases when in competition with other
- amygdala is more responsive as more testosterone is bound to its receptors
- testosterone weakens the PFC control of aggressive impulses from amygdala
Animal study that supports the link between testosterone and aggression
SILBER AND WAGNER (2004)
- male rats are more aggressive than females
- castrated males show reduced aggressive
- male vs male aggression starts at puberty
- injecting both male and female rats with testosterone increases aggression
Human studies that support relationship between testosterone and aggression
DABBS ET AL (1995)
- measured testosterone levels in the saliva of 89 male prisoners (violent and non violent)
- testosterone levels were higher in prisoners who committed violent crime
MIDGELEY ET AL (2001)
- body builders taking androgenic steriods
- 60% had higher scores on State Trait Anger Expression Inventory (measure of aggression)
- these who scored higher tended to be security staff or bouncers
Human studies that challenge relationship between testosterone and aggression
TRICKER ET AL (1996)
- gave 43 male ppts either 600mg a week for 10 weeks of testosterone or a placebo
- double blind experiment
- using 2 anger questionnaires ppts were tested before, during and after treatment
- aggressive behaviour and mood was also rated by people known by the ppts (parents and spouses)
no significant differences where found between the aggression and placebo group on any of the measures
Issues with evidence supporting relationship between aggression and testosterone
- evidence is correlation and so causation can’t be determined
- possible that in studies using prisoners, higher testosterone levels are the consequence of aggressive behaviour and not the cause
- researchers are looking at the wrong type of aggression, defensive aggression PINEL (2000) points out animals studies found testosterone affects social aggression not defensive
What is Freud’s Psychodynamic theory?
main points
- psyche is divided into 3 parts that develop over first 5 years of life
- any issues with development in first 5 years = unstable adult personality
- 3 states of mind
What are the 3 states of mind in Freud’s Psychodynamic theory?
- conscious mind
- preconscious mind
- unconscious mind
What is the conscious mind in Freud’s Psychodynamic theory?
- part of the mind that we are aware of
contains thoughts that we are currently thinking at any given moment
What is the preconscious mind in Freud’s Psychodynamic theory?
- part of the mind we are occasionally aware of
contains remembered dreams, feelings that haven’t been put into words and memories that can be recalled into the conscious mind without help
What is the unconscious mind in Freud’s Psychodynamic theory?
- rest of the psyche that we are totally unaware of
contains instincts and desires, fears, motives, most of our dreams and memories that have been repressed because they are too painful
What are the 3 parts of the psyche?
- ID
- Ego
- Superego
What is the ID ?
- most basic part, develops first in babies
- consists or urges and desires
not rational or reflective, made of only feelings and is based on the pleasure principle - is entirely in the unconscious mind
the Id doesn’t understand time or logic or the world, it wants what it wants immediately, if denied it becomes frustrated
What is the Ego?
- develops in toddlers
- thinking and decision making part that exists in conscious mind
- it understands time and the outside world, has no desires
role is to find a way to grant the id’s desires but can trick the id to desire something less pleasant with promise of a more pleasant reward
What is the Superego?
- develops between age 4 -6
- between the conscious and unconscious mind
acts as the morals and voice of conscience, tells the ego whether its thoughts are morally acceptable or not - when superego objects to egos thoughts it generates guilt and shame which the ego finds unbearable so it comes up with other thoughts that appease superego
if the superego doesn’t agree with id = anxiety
if id wants something superego finds immoral = guilt
if it doesn’t get what it wants = regret
How does Freud’s Psychodynamic theory explain aggression?
- Aggression is the result of frustration at the id not getting what is wants or getting something it displeases
- superego blocks the direct expression of aggression
- aggressive drive builds up in unconscious mind
- ego finds away to remove aggression using defence mechanisms
What defence mechanisms are used by the ego (and explain what they are)?
VICARIOUS AGGRESSION
- watching aggression ( someone else being aggressive)
SUBLIMATION
- channels the ids urges into something socially acceptable like art or work
DISPLACEMENT
- ids urges are acted upon but they are directed to a different target (blaming others)
DENIAL
- ids urges are acted upon but conscious mind refuses to admit and accept what they are
What is catharsis?
-> process of getting rid of built up emotions before a violent outburst in the form of explosive aggression, overt aggression (series of aggressive acts) or covert aggression
In terms of Freuds’s Psychodynamic theory people who act in aggressive ways …
- do not inhibit the expression of aggression (weak superego)
- cannot channel their aggression ( weak ego/ strong superego)
- aren’t good at using defence mechanisms
Evidence against Catharsis
BUSHMAN (2002)
- had a confederate anger the ppts
- experimental group could then punch a punch bag for a few mins (catharsis) while control group did nothing
- ppts could then act aggressive towards person who angered them by blasting them with white noise
- ppts in experimental group were sig more aggressive than control
VERONA AND SULLIVAN (2007)
- confederate acted in ways to frustrate ppts
- experimental group acts aggressive by pressing button to give someone (fake) electric shocks control group pressed a non shock button
- all ppts received a blast of uncomfortable hot air and then could act aggressively
experimental group were more aggressive than controls
Compare biological theory + freudian theory
is aggression nature or nurture?
bio theory
- nature = brain structures
- nurture = experience in lifetime
Freud theory
- nature = theory of evolution
- nurture = how parents teach you moral ( superego)
similar both view aggression as a combination of both
Compare biological theory + freudian theory
is aggression a physical or mental process?
bio theory
- physical = relies on physical components of brain
freud theory
- mental = result of unconscious activity and pressure build up
different bio is physical and freud is mental
Compare biological theory + freudian theory
Does aggression involve one or several processes?
bio theory
- several structures at one time, any go wrong (damage) aggresion occurs
freud theory
- psyche has 3 parts that all function properly for aggression
similar both explain that different structures must work properly for aggression to occur
Compare biological theory + freudian theory
What evidence is there for the explanation?
bio theory
- PET scans, case studies, experiments, objective measures
freud theory
- dream analysis, psychoanalysis subjective measures
different bio uses objective measure and freud uses subjective measures
Compare biological theory + freudian theory
is it scientific?
bio theory
- yes scientific evidence, reductionist and objective
freud theory
- yes tested theory
but hard to prove as it is subjective
What are the aims of the contemporary study BRENDGEN ET AL. (2005)?
- to estimate the size of genetic influence on physical and social aggression
- conducted a twin study to estimate and investigate the influence of factors on 6yo childrens social and physical aggression
What is the procedure of the contemporary study BRENDGEN ET AL. (2005)?
- twins were assigned as either MZ/ DZ twins based off appearance
- conducted in 409 classrooms
Teachers - competed a questionnaire where they rated each child on a 3 point liker scale ( 2 scores = social aggression and physical aggression)
statements -> ‘gets into fights’ or ‘tries to make others dislike a child’
Peer - shown photos of their classmates and asked to circle the photos of the 3 children who best fit the statements
statements -> ‘hits, bites, kicks’
What are the sample of the contemporary study BRENDGEN ET AL. (2005)?
234 twin pairs taken from the Quebec newborn twin study
44 MZ male
50 MZ female
41 DZ male
32 DZ female
67 DZ mixed
What are the findings of the contemporary study BRENDGEN ET AL. (2005)?
chi squared test used to show agreement btw teacher and peer ratings
physical -> MZ correlations 2x higher than DZ same sex
genetic factors have a higher contribution to physical aggression
social -> MZ and same sex DZ correlations were similar
social aggression is less linked to genetics
physical = mostly nature (genes) social = mostly nurture (environment)
What are the conclusions of the contemporary study BRENDGEN ET AL. (2005)?
- 50 - 60% of physical aggression is linked to genes
- other 40% of this is due to a non shared environment
- social aggression genes count for 20%, 20% is shared environment and 60% is from non shared environment
genes predispose children to aggression but social aggression is encouraged
What are the aims of the classic study RAINE ET AL (1997)?
- conducted a brain study using PET brain scanning to investigate relationship between brain structure/ function and aggression
- to see whether brain dysfunction predisposed people to violent behaviour
What is the procedure of the classic study RAINE ET AL (1997)?
- 2 groups one group pf NGRI murderers and one control group
PET SCANNING
- each ppt completed a practice CPT (continuous performance task) 10 mins before being injected with the tracer
- 30 secs before injecting tracer ppt started the real CPT (boost metabolic rate and brain activity) recorded before injection
- ppt continued CPT task and recorded
- after 32 mins ( time taken for tracer uptake) ppt was taken for PET scan
What is the sample of the classic study RAINE ET AL (1997)?
NGRI murderers = 41 ppts, 39 men and 2 women, 34.3 average age charged with murder or manslaughter
control group, matched to 6 ppts with schizophrenia
What are the findings of the classic study RAINE ET AL (1997)?
- no difference in performance of the CPT task in groups
prefrontal = NGRI less activity parietal = NGRI less activity temporal = no sig diff occipital = NGRI had more activity
corpus callosum = NGRI had less activity
amygdala = less activity on the right
hippocampus = more activity on the left
What are the findings of the classic study RAINE ET AL (1997)?
- how abnormalities in NGRIs might translate into violence
prefrontal deficit = lack of activity means more impulsice
limbic deficit = abnormalities in amygdala, hippocampus, thalamus hard to understand emotions
corpus callosum deficits = harder for hemispheres to communicate and make decisions
