biological Flashcards
what are the six key assumptions of biological psychology?
- All behaviour is determined by biological factors
- the central nervous system is a major influence on behaviour
- behavioural and psychological development is assumed to be based on changes in the brain and general biology
- process of evolutions can explain the existence of much human behaviour
- genes influence behaviour
- there is behavioural continuity between species so it makes sense to study animals and make generalisation to humans
What makes up the central nervous system and what is its role in human behaviour
- the brain
- the spinal chord
The CNS acts as an information processing and control centre for info we receive and response we make
The body receives information from our senses, the peripheral nervous systems send it to the CNS. The brain processes and integrates all the information and generates a response
What are the four lobes of the brain and the PFC and what are they responsible for?
FRONTAL LOBE:
- decision making
- planning and organising
- memory and attention
PARIETAL LOBE:
- sensory info
OCCIPITAL LOBE:
- visual information
TEMPORAL LOBE:
- memory and attention
PRE-FRONTAL CORTEX:
- part of frontal lobe
- executive functions such as inhibiting inappropriate responses, design making and motivational behaviour
What makes up the limbic system and what are their roles?
THALAMUS:
- relays info from senses
AMYGDALA:
- fear and anger
- fight or flight
HIPPOCAMPUS:
- memory formation
HYPOTHALAMUS:
- regulated bodily functions
- hormones such as adrenaline
What is a neutron and what is the structure (label)?
- a specialised cell within the nervous system
- axon
- dendrites
- cell body
- nucleus
- axon hillock
- myelin sheath
- sides of ranvier
- synapse
What is the synapse and what is its structure (label)
- where the communication between one neutron and the next takes place
- presynaptic neuron
- synaptic vesicles
- action potential
- synaptic cleft
- postsynaptic neuron
- protein receptor
- neurotransmitters
How do neurons influence human behaviour?
Neurons make a chain with each other forming a passage way that allows messages to be sent from one part of the brain to another keeping the brain and body working correctly.
They form new connections and change existing connections every time we learn something new
What is the function of neurotransmitters and give three examples of them?
- chemical messengers that take info around the brain
- released from post synaptic neuron after and action potential
- stimulate post synaptic neuron to make its own action potential
- they allow neurons to communicate with one another
SERETONIN:
- mood control
- pain, sleep, body temp and hunger
DOPAMINE:
- pleasure
- dependency (addiction)
NORADRENALINE:
- fight to flight
What are the four steps to synaptic transmission?
- An action potential moves down the pre-synaptic neurone and causes the vesicles filled with neurotransmitters to move closer to terminal membrane
- the vesicles fuse with terminal membrane in a process called exocytosis. This causes neurotransmitters to be released into synaptic cleft
- Neurontramitters bind with protein receptors in the post and pre synaptic neuron. Activation on the post synaptic neuron causes an increase of liklehoof for action potential. Activation in pre synaptic neuron causes the stop of releasing neurotransmitter
- Once neurotransmitter is released into synaptic cleft, it is removed by either, reuptake, broken down by exams or diffusion
Evaluate synaptic transmission as an explanation of how messages move around the brain
- evidence from brain scans which are objective and reliable (increase scientific credibility)
- much evidence has come from animals. To generalise from rat and cat brains may not be valid
- individual differences are not always taken into account. Some people have different levels of certain neurotransmitters.
What are recreational drugs and what ate reward pathways?
- recreational drugs are used in the absence of medical grounds for personal enjoyment.
- reward pathways are circuits of structures and nerves that are linked to the activities of specific neurotransmitters
- Dopamine pathway are activated by natural rewarding behaviours such us ex or eating. Make us more likely to repeat behaviours
What are three ways in which drugs may affect synaptic transmission?
- Increasing the amount of dopamine that is released
- Blocking pre synaptic transpoters so that reuptake is stopped
- stopping the actions of enzymes that would normally break down the neurotransmitter
How does cocaine effect synaptic transmission?
- cocaine is a highly addictive stimulant
- it blocks the transporter receptors on the pre synaptic dopamine neurons in the ventral tegemntal area
- therefore pre gnostic neuron do not reuptake dopamine so it stays in the synaptic cleft longer
- this prolongs and intensifies the stimulation of post synaptic neuron
- user experiences euphoria
How does drug addiction occur?
- brain is a self regulating system so reacts to the over production of dopamine
- reduced how much dopamine it naturally produces
- brain will no longer operate properly without the drug
- without drugs, people experience dysphoria
- motivation to self administer is high to re-experince eurphoria
- this leads to repeated use snd therefore further down regulate the production of dopamine
- tolerance for the drug is built up, must take a higher dose to get high
- causes person to be physically dependent in order to avoid experience of withdrawl
Evaluation of how drugs effect brain functioning and synaptic transmission
- well controlled scientific evidence using animals (van den over)
- brain scanning techniques (Li et al used fMRI scans to show heroine had changed functioning and connections in the brain)
- applications such as enabling scientists to develop medications to help addicts
- brain scans are not sophisticated enough to show everything
- evidence comes from animals which may not straightforwardly generalise to humans
What is the aim of Van Den Oever’s study?
to investigate acute changes in the molecular composition and function of synapses in the medial prefrontal cortex upon re-exposure to heroin cues
What was the procedure of Van Den oevers study?
Stage one:
- experimental group trained to self administer heroin. When presented with an audiovisual cue, if they poked their nose in a hole, they received a dose of heorin
- control group, same but received sucrose solution
Stage two:
- experimental group split in two
- some rats kept in operate cage fro 21 days (abstinence)
- other rates kept in self administration cage but did not receive heroin (extinction)
Stage three:
- both groups split in two
- hald absietnce and extincction rats were exposed to drug associated cues for 60 min but did not receive heroin
- other hand we’re places in self adminstarion boxes but were not exposed to drug associates cues
Stage 4:
- all rats were decapitated
- brains were analysed using mass spectrometry technique which allowed detection of subtle changes
What were the results and conclusions from van den oever study?
Results:
- behavioural evidence of relapse (rates re-exposed to drug cues demonstrated greater amount of frug seeking behaviour compared to those not re-exposed)
- composition of synapses in the medial prefrontal cortex (rates re-exposed to drug cues had lower than normal levels of AMPA receptors in the medial prefrontal cortex)
- endocytosis preventive drugs reduced the amount of drug seeking behaviour
Conclusions:
- after a period of abstinence, exposure to drug associates cues can trigger a relapse back to drug seeking behaviour. Therefore, recovering addicts need to be removed from sung associated cues
- Rates re-exposed to drug associated cues related to heroin, is linked to lower number of AMPA receptors. Therefore, the molecular composition and function of the synapses had changed
- the reductions of AMPA rectors in prefrontal cortex is causing a relapse in drug seeking behaviour.
Evaluate Van Den Oevers study?
Generalisability:
- male white wistar rats used
- areas in the brain for drug addiction are similar in rats and humans (medial prefrontal context and reward pathways)
Reliability:
- used standardise procedures (all had same amount of assistance/extinction)
Applicability:
- preventing drug addicts from relapse such as a drugs preventing endocytosis
Validity:
- control over extraneous variables such as a control group
- reductionist as it only focuses on medial prefrontal cortex and ignores social factors
Ethics:
- sample was rats as it would be unethical on humans
- rats were harmed (catheters and killed)
What are hormones and what are their role in human behaviour
chemical substances produced in a specialised gland and transported in blood to stimulate specific cells or organs into action (endocrine system)
Hormones influence:
- sensory input
- intergration by CNS
- Motor output by muscles
- hormones change the probability that a particular behaviour will happen in certain situations and can also change the intensity of a behaviour
How do hormones affect development in stages of life?
In the womb:
- development of brain influenced by reproductive hormones
- impact on sex differences causing male and female brains to develop slightly differently
Early Childhood:
- stressful environments cause the release of cortisol
- if children experience high cortisol levels, this can impact development of the brain
- children experiencing abuse may overproduce neural connections in fear and anxiety and may under produce neural connections for reasoning and planning
Puberty and adulthood:
- hormonal imbalances in adulthood can result in brain changes
- these make a person more susceptible to depression, anxiety, alcoholism and drug abuse
- e.g puberty and menopause
evaluate the use of hormones to explain human behaviour
- high scientific credibility as standardised measures such as blood tests
- supporting evidence making it reliable
- ethical issues so it is more correlational research than cause and effect
- practical problems as many variables can’t be controlled
- reductionist as it only looks at hormones
What is evolution and how does it explain human behaviour?
The gradual development of different kinds of living organisms. This is done through natural selection
Behaviour that have aided human survival are then inherited by offspring. HBhevaour is therefore genetically determined
Example: languages would have helped us communicate more easily and is therefore a valued trait. This is then passed on to the next generation
Evaluate the use of evolution by natural selection as an explanation to human behaviour
- theory is directly observable and therefore falsifiable
- high scientific credibility as there is evidence (Darwin, Galapagos islands
- twin and adoption studies how role of genetics
- evidence is limited as there is no physical fossil record
- DNA evidence is also limited
- reductionist
What are the three biological explanations of aggression?
- brain structure and functioning
- hormones
- evolution and genetics
How is the amygdala linked to aggression?
- enables our instinctive reactions
- amygdala is activated in threatening situations causing high to flight
- necessary to initiate aggression
- reactive agression
Evidence:
Case study - Charles Whitman went on a shooting rampage at uni of texas killing 14. Was found to have a brain tumour in the hypothalamus and near the amygdala
Brain scans - fMRI - coccaro found people with intermittent explosive disorder had an overactive amygdala compared to controls.
How is the pre-frontal cortex linked to aggression?
- various executive functions
- allows us to control reactive aggressive impulses that stem from amygdala
- inhibits us from automatically reacting and allows us to think
- proactive aggression
Evidence:
Case study - phones cage suffered damage to his pre frontal lobes. went from a quiet family man to aggressive drunk
Brain scans - CAT - Grafman studied veterans from Vietnam war and found those with damage to pre frontal cortex wherefore aggressive than those with damage in other areas
Brain scans - PET - Raine found violent murderers had brain dysfunction in pre frontal cortex
How do neurotransmitters link to aggression?
- low levels of serotonin are associated with an increased tendency towards impulsive and aggressive behaviour
- low levels of serotonin in pre frontal cortex results in it not being able to inhibit the fight to flight so increases likeuooh of reactive aggression
- low levels of serotonin all means the amygdala will be more active
Evidence:
Clinical drug studies - antidepressants than increase serotonin levels tend to reduce irritability and impulsive aggression
Lab experiments with rodents - Ferrari found rats serotonin levels decreased when they were anticipating a fight with another rat (rats fought for 10 days and on the 11th day no rat was introduced and serotonin was measured)
What was the aim of Raines study?
- to find out which brain areas were dysfunctional in violent offenders using PET scans
- he hypothesised that participants pleading NGRI would show brain dysfunction in areas of the brain previously associated with violence
What was the sample and procedure of Raines study?
Sample:
- 41 individuals charged with murder pleading NGRI
- 39 men and 2 women
- control group was matched on age, sex and psychiatric illness
Procedure:
- p’s required to perform a continuous performance task (stare at a screen whilst blurred symbols appeared and p’s had to press a button when a certain symbol appears so it required constant attention)
- did this for 10 min as practice
- a radioactive glucose tracer was injected into participant
- after a further 32 min of task, the p’s brains were PET scanned in order to determine the glucose metabolic rate throughout the brain
What were the results and conclusions from Raines study?
RESULTS:
1. lower levels of brain activity in both hemispheres compared to control group in the pre frontal cortex
- Lower levels of brain activity compared to control group in various areas of parietal cortex
- lower levels of brain activity compared to controls in both hemispheres in the corpus callosum
- abnormal asymmetrical levels of limbic system activity compared to controls in thalamus, amygdala and hippocampus
- no overall difference in level of activity in the amygdala, temporal lobe and thalamus
CONCLUSIONS:
- reduced activity in certain areas of the brain such as the pre frontal cortex and abnormal asymmetries of activity in the limb system could predispose a person towards violent behaviour
- lack of functioning in pre frontal cortex means reduced ability to regulate activity of limit system and is thus less able to control aggressive responses
- abnormal functioning in amygdala results in murderers being fearless
- hippocampus and thalamus are related to learning so abnormal citify could resell in them being unable to modify their own behaviour by learning the consequences
Evaluate Raines study
Generalisability:
- large sample used
- representative for a rare category
- mostly men
- only murderers pleading NGRI so may not represent other violent offenders
Reliability:
- high
- standardised preocedures such as using the same scanner and do cpt for same time
- PET scans are quantitive
Applicability:
- suggests pre dispositions to committing violent crime so could make early interventions and preventions
- however cause and affect is not established
Validity:
- control over extraneous variables such as not taking medication for two weeks and having a control group
- could not control some variable such as the participants upbringing
- reductionist, ignores social factors
- resolution of PET scans are lower than others so images may not be accurate
Ethics:
- ethical guidelines largely followed such as no deception and consent
- participants my have has psychiatric illness so may not be fully aware of implications in giving consent
- participants subject to some harm including a radioactive in section and being off any medication for two weeks
Evaluate brain structure and functioning as an explanation for aggression
STRENGHTS:
- high scientific credibility as brain scanning is objective and falsifiable (raine, graffman, coccoro)
- supporting evidence including lab experiments with animals and people (raine and ferrari)
- practical applications such as physical treatments (in the past a pre frontal lobotomy was used)
WEAKNESSES:
- research has practical and ethical issues as we cannot establish cause and effect
- generalisability from animals is limited as human shave more complex brains than rats
- reductionist as it ignores social factors such as social learning
How are hormones (testosterone) linked to aggression?
- male sex hormone
- high levels of testosterone are linked to high levels of aggression
- testosterone may influence serotonin levels in areas involved in aggressive reactions
Maccoby and Jacklin: Gender differences
- boys and consistently more aggressive than girls
- men are more frequently charged with violent offences
- males produce more testosterone than women
Evidence:
- Dabbs - measured testosterone in saliva of 89 male prisoners some vine crime some non violent crime. The more violent criminals had higher testosterone levels
- Dabbs - testsoterone was high in both male and female violent offenders compared to non violent offenders
- Olweus - boys with higher levels of testosterone were more impatient and irritable
- Wagner - observed aggression levels in male mice. After castration aggression levels dropped but when they were injected with testosterone their aggression levels rose back to pre castration levels
How is cortisol linked to aggression?
- produced by adrenal gland to manage stress levels
- normal cortisol levels inhibit aggressive behaviour but low levels are linked to increased aggression levels
Barzman:
- took saliva from 7-9 year old boys in a psychiatric hospital
- obtained aggression rating from nurses
- low levels of cortisol in saliva were linked to a higher number of aggressive incidents recorded by nurses
Evaluate hormones as an explanation for aggression
STRENGHTS:
- high scientific credibility as hormones can be measures in an objective and quantile way such as blood tests
- supporting evidence in humans and animals (dabbs,wagner)
- practical applications such as use of drugs to reduce testosterone
WEAKNESSES:
- findings are largely correlational not cause and effect so scientific credibility is lowered
- reductionist as it only looks at hormones
- overemphasis on the role of nature where social learning may play a part
Explain evolution as an explanation for aggression
- aggression is well adapted to a hostile environment and would therefore aid survival
- aggression would have been linked to survival of the fittest as it would be needed to defend one self from attacks and protect a mate.
- non aggressive individuals would have been less likley to survive
Buss:
- argued natural selection is an explanation for aggression in humans
- humans want the best resources so fight for them
- aggression proves dominate for a mate and reputation
- aggression is developed for protection of valuables
Barash:
- gender differences
- professions that involve viokncen such as soldiers, executioners, hunters and slaughterhouse workers were mainly male
- males would have been the ones providing for and protecting the females
Wilson and Daly:
- status competition
- males partcpaiate in risky behaviour such as violence because females will be attracted to aggressive risk takers
- they compete for higher status than other males, increasing their chances of winning a high value mate
- analysed data from police records in Detroit
- more homicides were committed by young, unmarried males as well as them being the victim mostly.
- most conflict involve conflict caused by retaliation, showing off and jealousy
Evaluate evolution as an explanation for aggression
STRENGHTS:
- scientific credibility of original theory is high as Darwin used scientific observations
- evidence such as wilson and daly
Weaknesses:
- scientific credibility when applied to behaviour is low as we cannot empirically test behaviour that is dependent on environment
- reductionist as it overlooks the role of social and cognitive factors
- determinism as it implied humans do not have free will in choosing an aggressive response
What is the aim of Gottessman and Shields study?
aimed to see wether schizophrenia had a genetic basis. They examined records of patients in a psychiatric hospital over a sixteen year period
What was the procedure of Gottessman and Shields study?
- identified 57 schizophrenic patients that were one member of a twin
- 24 were monozygotic and 33 were dizygotic
- collected data in many ways such as hospital notes, self report questionnaires, self report interviews, personality testing and tests to measure disordered thinking
- split into 4 ctatagroies based on which twin was hospitalised and what diagnosis twins had
What were the results and conclusions of gottessman and shields study
RESULTS:
- concordance rates for schizophrenia were higher in females compared to males
- concordance rates were higher in both MZ and DZ twins for severe schizophrenia compared to mild schizophrenia
- concordance rate for severe schizophrenia was higher in MZ twins (75%) compared to DZ twins (22%)
CONCLUSIONS:
- schizophrenia does have a biological basis
- chance of developing schizophrenia is influenced by a person’s genes
- schizophrenia is not totally due to genes as the concordance rates in MZ twins was not 100%
What was the aim and procedure for Ludekes adoption study?
Aim: determine wether peoples attitudes could be influenced by their genes (particularly looked at authoriantarism, conservatism and religiousness) by examining these attitudes in MZ and DZ twins that were separated at birth
Procedure:
- studied 66 MZ and 53 DZ twins that were separated at infancy and reunited later in life
- p’s were all members of the Minnesota study of twins reared apart group
- filled in various self report measures to determine their attitudes
What were the results and conclusions from Ludekes adoption study?
RESULTS:
- strong positive correlation across all sales in the MZ twins
- only conservatism measure scored stronger for DZ twins
CONCLUSIONS:
- genes do have an influence on peoples attitudes towards traditionalism
Evaluate the use of twin and adoption studies in explaining behaviour
STRENGHTS:
- twin studies have high scientific credibility as there is objective and quantitive data
- practical applications from twin studies can help find treatments and preventions
- adoption studied have high scientific credibility as they have a clearer isolation of environmental influences
WEAKNESSES:
- twin studies share same environments so scientific credibility is lowered
- generalisation from twin studies is hard as samples tend to be small
What are Freud’s key assumptions/ basic principles?
Key Assumption:
- our awareness is in layers, what we think and feel and what motivates us is in the unconscious mind
Structure of the mind:
Conscious - only part you are aware of
Preconcious - readily brought to conscious
Unconscious - tied to anxiety, conflict and pain
Structure of personality:
ID - pleasure principle and immediate gratification
EGO - reality and controls ID
SUPER EGO - morality principle
Defence mechanisms:
- ego keeps the id and super ego balanced
- displacement (divert emotions)
- denial (reject painful thoughts or feelings)
- Repression (push info out of consciousness)
- projection (put on someone else)
- regression (engage in old characteristics)
What is Freuds theory of aggression?
Psychodynamic theory of aggression
We are born with an inborn uncouncoius drive
EROS - motivation to live, love and create experiences
THANATOS - death instinct which causes aggressive behaviour
First two years we are driven only by eros and thanatos which are in direct conflict with one another. Tension therefore builds up until we can no longer control it, resulting in aggressive behaviour
At two, the ego develops and there is an understanding that aggressive behaviour is only appropriate some of the time. Aggression is kept in the unconscious mind using defence mechanisms
Aggression can be controlled through catharsis which is when we release pent up aggression. We can put energy into a safe activity
Evaluate Freud’s psychodynamic explanation of aggression
STRENGHTS:
- some evidence to support such as case studies like little hans (big amounts of qualitative data)
- Practical applications such as talking cures like therapy and catharsis to manage aggression
WEAKNESSES:
- scientific credibility is low due to use of case studies
- they are open to subjective interpretation and are not representative
- theory is not falsifiable as his theory is not directly observable or measurable
What was the title of your practical in biological psychology?
A correlational study to investigate wether there is a relationship between testosterone levels and aggression levels
What was the aim of your practical is biological psychology?
The aim of this study was to investigate, using correlational method, wether testosterone levels can be linked with aggression levels
What was the hypothesis for your practical in biological psychology?
There will be a positive correlation between testosterone, using the 4d/2d ratio measured in mm across both hands, and aggression levels measured by self rating using the buss perry aggression scale
What are two strengths and two weaknesses of your practical in biological psychology?
STRENGTH:
- internal validity increased as we used self report method that can ask questions about previous experiences
- ethical as it was carried out in a classroom where the teacher made sure guidelines were followed
WEAKNESSES:
- validity lowered as self report means p’s may not have been fully honest
- not generalisable as only 14 psychology students used
What is your key question in biological psychology?
Can the use of animals in psychological research be justified?
What are the for and against arguments for your key question in biological psychology?
FOR:
- allows procedures that would not be possible in humans
- found treatment for Parkinson’s disease using animal research
- Bennazzouz used monkey to trial treating Parkinson’s disease
- humans and animals have enough similarities in their psychology and evolutionary past in common to justify conclusions drawn from animas being generalised to humans
- animals in psychological research have shorter life spans than humans so developmental processes are easier to observe
- animals are good participants (they do not try and know the aim)
- examples such as van den oever and wagner
AGAINST:
- physiology and behaviour in animals may be similar to humans but they are not the same. Humans have more complex emotions, cognitions and social interactions
- environment and stress animals endure in the labs can affect their behaviour and therefore results are not valid
- alternatives to animal reproach are improving with technology such as computer models and virtual reality.
