Biological Psychology Flashcards
Which 2 parts make up the central nervous system?
Spinal cord and Brain
What are the 2 halves of the brain called?
hemispheres
What does the brain do?
coordination centre of sensation and intellectual and nervous activity
What does the spinal cord do?
reflex actions -links the brain to the rest of the body (peripheral NS)
Define ‘contralateral’
Left side of the brain controls right side of the body and vice versa
What is the cerebral cortex?
outer layer of the brain
What are convolutions?
folds on the cerebral surface (wrinkly)
What are gyri and sulci?
ridges and valleys in the cerebral cortex
What is lateralisation?
different functions for each hemisphere of the brain
What is localisation?
within a hemisphere, certain behaviors are localized to one specific area
What is the function of the frontal lobe?
-controls high level thinking, planning and problem solving -contains motor cortex -contains Broca’s area -one in each hemisphere
What is the motor cortex?
strip along the top of the brain
What does Broca’s area do?
left frontal lobe responsible for speech production
What does the parietal lobe contain?
somatosensory cortex
What does the somatosensory cortex do?
processes sensory information from the skin -touch, temperature and pressure -contralateral
What does the temporal lobe do?
contains auditory cortex (which is contralateral) -processes location, volume and pitch of sounds -role in language
What does Wernicke’s area do and where is it located?
left temporal lobe -understanding of languages
What is the occipital lobe responsible for?
contains primary visual cortex -contralateral
What does the visual cortex do?
interprets messages from our eyes into images we can understand
What is the corpus callosum?
link of fine fibres which connect the hemispheres together -shares info between hemispheres
What does the Thalamus do?
brain relay station -receives info from senses -role in sleep and OCD
What does the Hypothalamus do?
controls motivational behaviors (hunger, thirst, sex drive) -stress response -maintains balance in functions (body temp, hormones)
What is the limbic system responsible for?
contains several structures -regulates emotional response
What does the cerebellum do?
coordinates posture, balance and movement -receives and integrates info from spinal cord + other areas
Explain the parts of the Nervous system.
nervous system - peripheral or central NS -peripheral - autonomic or somatic NS -CNS - brain and spinal cord -autonomic NS - sympathetic and parasympathetic NS
What is the sympathetic NS responsible for?
preparing the body for fight or flight
What does the autonomic NS do?
-controls body’s involuntary movements -controls the organs of the body
What is the peripheral NS?
all of the NS outside CNS
What does the somatic NS do?
-controls body’s voluntary movement -transmits signals to and from senses and muscles
What is the nervous system?
The network of nerve cells and fibres which transmits nerve impulses between parts of the body
What does the parasympathetic NS do?
restores body to resting levels after fight or flight
What are the 3 types of neuron?
Sensory, relay and motor
What does the sensory neuron do?
receives messages from receptors -travels along nerves in the peripheral NS to the CNS -has long dendrites and short axons
What does the motor neuron do?
carries messages from the CNS to effectors -along nerves in the peripheral NS -short dendrites and long axons
What does the relay neuron do?
connects sensory and motor neurons -only found in CNS -short dendrites and short axons
What are neurotransmitters?
chemical messages between neurons in the brain -allows brain to process thoughts and memories -each NT has particular function (excitatory or inhibitory)
Explain the 7 stages of Synaptic Transmission.
1: nerve impulse travels down an axon 2: nerve impulse reaches synaptic terminal 3: triggers the release of neurotransmitters 4: neurotransmitters fired into synaptic gap 5: neurotransmitters bind to receptors on the dendrite of adjacent neuron 6: if successfully transmitted, NT taken up by post-synaptic neuron 7: message will continue to be passed on via electrical impulses
What is an agonist drug?
-imitates natural neurotransmitters -fools the brain into activating pleasure centres -much more powerful than natural occurring NT’s
What is an antagonist drug?
boosts amount of normal neurotransmitters -triggers brain pleasure centre
Which 2 recreational drugs does the course focus on?
cocaine and heroin
What does cocaine do?
-stimulant effect on CNS -alters synaptic transmission involving several NT’s -most profounding effect on activity of dopamine
How does cocaine impact the role of dopamine?
blocks reuptake of dopamine by binding with dopamine transporter molecules on terminal buttons of presynaptic neuron -synapse flooded with surplus of dopamine
What are long term effects of dopamine?
dopamine receptors become downregulated -fewer receptors active, some damaged and shut down -quantity of dopamine produced decreases -tolerance increases, withdrawal, cravings
What does heroin do?
depressant effect on CNS -processed into morphine, which binds with specific receptor
What are long term effects of heroin?
neural transmission = down regulation -receptors desensitized, tolerance increases
Evaluate a strength of recreation drug research.
research supporting the role of dopamine -non-human animal studies (mice) -show that dopamine is released from a specific part of the brain
Evaluate the opposing argument of recreation drug research.
-poor validity of non-human animal studies -human brain ore complex -complexity of recreational drug effects can’t be explained by just one mode of action of a drug BUT -studies of humans as well (similar results)
Evaluate an application of recreation drug research.
other drugs developed with reverse mode of action -Naloxone blocks the effect of heroin, can help with withdrawal process and reduce symptoms
What does the amygdala do?
controls emotion responses (particularly fear)
What does the hippocampus do?
encodes long term memories
What would happen if the prefrontal cortex was damaged? (Raine et al)
person would seek immediate gratification -more negative emotions
What are the 3 types of brain scan?
CAT, PET and fMRI
Outline how CAT scans work
xrays -detailed cross-section images of inside of body
Outline 2 advantages of CAT scans.
useful for revealing abnormal structures -high resolution, good quality images
outline 2 disadvantages of CAT scans
high levels of radiation -only provide structural info (still images)
Outline how PET scans work
measure metabolic activity in brain -radioactive substance injected (radiotracer) -active areas = yellow
outline 2 advantages of PET scans
shows brain in action -provide evidence of localisation of functions
outline 2 disadvantages of PET scans
results sometimes not easy to interpret -ethical issues, radioactive substances can damage tissues
outline how fMRI scans work.
-uses radiowaves to measure blood oxygen levels in brain -blood directed to active areas -picked up through radio signals which produce 3D images
outline 2 advantages of fMRI scans
-doesn’t use radiation (safe) -extremely clear images
outline 2 disadvantages of fMRI scans
expensive to use -only effective if person stays perfectly still
what does serotonin do?
inhibitory effect on transmission between neurons -self control -regulates sleep patterns -low levels = aggression
who studied the role of serotonin on aggression and how?
Virkkunen et al -compared levels of serotonin for violent impulsive and violent non-impulsive offenders
What is the link between serotonin and dopamine?
serotonin underactivity stimulates dopamine overactivity, which causes a link to aggression and impulsivity
Evaluate a strength for the role of serotonin in aggression
-Pardini et al: 56 males who had been involved in aggression study 20 years earlier, some now criminally violent -fMRI scans found strong negative correlations between amygdala volumes and aggression levels -supports influence of amygdala
Evaluate an opposing argument for the role of serotonin in aggression
-often just correlational results (not cause-and-effect) -may be 3rd variable involved
Evaluate a differing theory for the role of serotonin in aggression
some researchers have tried to overcome issue with correlation -using drugs known to increase serotonin activity -evidence for link between serotonin and aggression that goes beyond using correlational findings
Evaluate an application for the role of serotonin in aggression
serotonin agonist drugs called serenics = anti aggressive effects in animals and humans
What are the 6 ways of studying the brain?
MRI scans -EEG (Electroencephalography) -Post-mortem -Lesioning (animals) -Measuring hormones -Identifying genes
What was the aim of Raine et al.’s study?
use brain scanning technology to identify brain impairments in people charged with murder who had pleaded not guilt by reason of insanity
What was the procedure of Raine et al.’s study?
-41 murderers & 41 non-murderers -matched pairs design (matched by sex, age, ethnicity) -control ppts = no meds, physical examination, psychiatric interview -PET scan, then continuous performance task, then 2nd PET scan immediately after
What was the findings of Raine et al.’s study?
CORTICAL REGIONS -murders = lower glucose metabolism in: prefrontal areas, parietal areas -higher in: occipital lobe (not previously linked) SUBCORTICAL REGIONS -murderers = lower metablism in: corpus callosum, left amygdala, left temperal lobe and hippocampus -higher in: right amygdala, right temporal lobe and right thalamus (not previously linked)
What was the conclusions of Raine et al.’s study?
-murderers NGRI = impaired functioning in areas linked to violence - dysfunctions of single brain area can’t explain violence -behavior only expressed when social, environmental and psychological conditions are ‘right’
Evaluate a strength of Raine et al.’s study.
experimental controls
Evaluate an opposing argument of Raine et al.’s study.
key element not controlled -ppts not randomly allocated to experimental or control group -failure to match on some variables
Evaluate a differing theory of Raine et al.’s study.
inappropriate PET scanning technique (may give misleading results) -reduced internal validity
Evaluate an application of Raine et al.’s study.
understanding biological evidence -brain structures only offer partial explanation
Outline evolution by natural selection
genetic differences & spontaneous mutations cause variation -advantageous characteristic passed on (reproduction) = retained in population and become more frequent -leads to adaption
When does natural selection occur?
survival of the fittest -competition for scarce resources
explain sexual selection
choosing mates based on specific traits and then those traits will increase in the population
State how evolution may cause aggression
guarding your offspring -guarding your partner
Evaluate a strength for evolution, natural selection and aggression
explains gender differences -men more aggressive (better hunters) -cooperative females = more likely to be naturally selected, therefore = reduced aggression
Evaluate an opposing argument for evolution, natural selection and aggression
any evolutionary explanation is uncertain -just correlational -may be other influencing factors
Evaluate a differing theory for evolution, natural selection and aggression
-can’t explain cultural differences -differences not universal -cultural norms can change aggression levels
Evaluate an application for evolution, natural selection and aggression
understanding relationships -partners who will enhance reproductive success -males prefer younger women = more likely to be fertile -women prefer older and wealthier men = children well supported
What are hormones?
biochemical messengers that are transported around the body in the bloodstream
What is the role of hormones?
crucial in fight or flight response -helping to fuel aggressive response (e.g. increasing HR)
What is the role of testosterone?
-aggression -Dolan et al. = positive correlation between testosterone levels and aggressive behavior in sample of 60 male UK offenders
Explain the dual-hormone hypothesis
-cortisol: protect body against stress -high levels of testosterone = aggression only when cortisol levels are low -cortisol high = testosterone’s influence on aggression blocked
Explain female aggression
lower testosterone levels -non-biological factors related to gender roles may be influencial
Evaluate a strength for hormones and aggression.
-research support -Dabbs + Hargrove: testosterone levels of 87 female prison inmates -degree of criminal violence positively correlated testosterone levels -link found in male prisoners = same results: higher validity of association
Evaluate an opposing argument for hormones and aggression.
correlational only -changing testosterone level and aggression may be result of changes of another hormone
Evaluate a differing theory for hormones and aggression.
difficult to determine testosterone levels -may not provide valid indicator of testosterone level in relation to aggression
Evaluate an application for hormones and aggression.
controlling aggression -e.g. testosterone lowering drug reduced levels of sexually aggressive behavior in some offenders
Outline the 3 parts of our mind according to Freud’s theory.
1: conscious = thinking which the individual is aware of 2: preconscious = readily available for access if you try 3: unconscious = main part, info we can’t access, forgotten
Explain Freud’s psychodynamic explanation of aggression
-born with 2 major instincts: life and death -life = Eros (survival + reproduction) -death = Thanatos
What age are the Id, Ego and Superego developed
Id = 0-2 -Ego = 2 -Superego = 3-6
Explain the Id and the pleasure principle
entirely unconscious mind -instincts and impulses that satisfy immediate pleasure and gratification -makes aggression unavoidable
Explain the ego and the reality principle
-logical and rational thinking -mostly conscious mind -between unrealistic desires and social reality -doesn’t directly fulfill id’s aggressive urges -no moral sense
Explain the superego
-conscience and moral sense of right and wrong -aggression is destructive -opposes id’s aggressive drive through guilt & shame
What is catharsis?
releasing aggression or aggressive thoughts -“letting of steam”
Give evidence for and against catharsis
FOR -Verona + Sullivan: people who reacted aggressively when frustrated = reduced HR AGAINST -Hokanson: only releases tension in short run, increased likelihood of aggression later
What is the contemporary study?
Brengden 2005
What were the aims of Brengden’s study?
investigated aggression in MZ and DZ twins to see: -extent that social + physical aggression is explained by genetic & environmental influences -whether social + physical aggression overlap has a direct affect
What procedure did Brengden’s study follow?
-twin study deign -rated for social + physical aggression -234 pairs, 6 years old -teacher ratings: rated students on 3 point scale in response to given statements -peer ratings: photos, nominate 3 who best matched behavior descriptions
What findings did Brengden’s study give?
-20% (teacher) and 23% (peer) of social aggression explained by genetic factors -physical aggression mostly explained by genetics -moderate but significant correlation between social + physical aggression (overlapping genetic influences) -high physical ag
What conclusions did Brengden’s study give?
genetic characteristics cause some children to be aggressive -HOWEVER further analysis indicated that specific form of aggression = more influences by environmental factors -directional relationship
Evaluate a strength of Brengden’s study.
-multiple data sources (peers and teachers) -2 sets of similar ratings = provides some reassurance that they are valid + reliable measures of aggression
Evaluate an opposing argument of Brengden’s study.
based on equal environments assumption -assumption may be violated = undermining validity of twin study method
Evaluate a differing theory of Brengden’s study.
-Derks (2006): study of aggression in adolescent twins, used statistical methods to show assumptions not violated so reasonably valid results
Evaluate an application of Brengden’s study.
effective interventions to reduce aggression -focus on preventing or reducing physical aggression in early years -interventions could stop physical aggression from turning into social aggression
What is the key question?
What are the implications for society if aggression is found to be caused by nature not nurture?
What are the main points of paragraph 1 of the key question answer?
aggression
What are the main points of paragraph 2 of the key question answer?
-no element of choice -can’t help our biology, shouldn’t be punished -genes and brain structure -born with certain abnormalities
What are the main points of paragraph 3 of the key question answer?
-aggression provoked in animals if certain brain regions (limbic system) are stimulated -Whitman: serial killer, brain tumor on limbic system, not his fault -aggression centre of brain in limbic system -high testosterone + low cortisol (Hank + Dabbs et al
What are the main points of paragraph 4 of the key question answer?
environment, nurture, choice -avoid environments that likely trigger aggressive behavior, retraining to react differently
What are the main points of paragraph 5 of the key question answer?
-cortisol = stress hormone, triggered by stress in environment -animals’ brains stimulated in limbic system showing aggression: coming from environment -environmental factors which perhaps gives individual some control over behavior (avoid stressful situa
What are the main points of paragraph 6 of the key question answer?
biological: should we punish? ethical? treatment instead of prisons? people offered help, not their fault?
What was the biological practical hypothesis?
tall people will be less aggressive than small people
What scale was used for our practical?
Buss-Perry scale
