Biological Psychology Flashcards
Define brainstem
part of the brain which connects the upper brain to the spinal cord
Define Brain
the organ in your head, made up of nerves which processes information and controls behaviour
Define hemisphere
half of the brain (left/right halves)
Define cortex
the outer layer of the brain
Define spinal cord
pathway of nerves in the spine, connecting the brain to the rest of the body
What is the CNS made up of?
the brain and spinal cord
What is the PNS made up of?
nerves that connect the CNS to the skin, muscles and organs
Where is the spinal cord connected to?
connected to the brain by the brainstem
What is the brain responsible for?
reflex actions and conscious awareness, where decision making takes place
What are the two hemispheres of the brain connected by?
The corpus callosum
What is the corpus callosum?
a bundle of nerve fibres
What does the corpus callosum allow the hemispheres to do?
allows the halves to communicate with each other
What is brain lateralisation?
the left and right hemispheres have different specialised functions
Which side of brain controls the right side of the body?
left
Which side of the brain controls the left side of the body?
right
What does the right side of the brain control?
spatial skills, creativity and musicality
What does the left side of the the brain control?
language, speech and writing skills
Where is the frontal lobe?
front of the brain
What does the frontal lobe do?
problem solving, attention control and impulse control
Where is the parietal lobe?
Top of the brain
What does the parietal lobe do?
perception, face recognition, touch sensations
Where is the occipital lobe?
back of the brain
what does the occipital lobe do?
vision and making sense of images
where is the cerebellum?
between the brain and spinal cord
what does the cerebellum do?
connects the two parts of the central nervous system and regulates motor movements
what does the brainstem do?
connects the two parts of the CNS
Where is the temporal lobe?
sides of the brain
what does the temporal lobe do?
controls hearing, sounds, speech, memory
What is the amygdala known as?
the centre of emotion in the brain
what does the amygdala control?
instinctive feelings and reactions to the environment, including aggression.
what is the hypothalamus?
maintains internal homeostasis by regulating hormone release from the pituitary gland, including hormones that regulate sexual functions
what is the hypothalamus linked to?
linked to aggressive behaviours in males via production of testosterone.
what does the prefrontal cortex do?
the very front of the brain that governs interaction and behaviour regulation. it governs control and makes us double think our actions
what is the prefrontal cortex connected to?
the amygdala and hypothalamus
what does damage to the prefrontal cortex cause?
inability to control impulses and consequently is related to aggression
Define neuron
nerve cell in the nervous system that transmit and receive chemical messages, through the release and uptake of neurotransmitters
define cell body
main part of the cell where the nucleus sits, contains mitochondria
define nucleus
houses genetic material for that particular neuron
define dendrites
branches at the top end of the neuron that receive messages from other neurons
define axon
long branch from the cell body that passes electrical impulses down to the end of the neuron to allow it to communicate with others
define myelin sheath
fatty deposit that provides electrical insulation for an axon and allows electrical nerve impulses to be passed along
define nodes of ranvier
gaps between adjacent myelin sheaths
define axon terminals/terminal buttons
the very end of a neuron where the nerve impulse becomes a chemical message that can be passed to the dendrite of another neuron
define neurotransmitter
chemicals within the nervous system that pass chemical messages from one neuron to the next, across a synapse
define excitatory
making a neuron more likely to trigger an action potential
define inhibitory
making a neuron less likely to trigger an action potential
define synapse
the gap between two neurons (axon terminal of the pre-synaptic neuron) where neurotransmitters pass on their chemical messages
define action potential
the process where an electrical impulse is triggered by the change in electrical potential of the neuron, causing release of a neurotransmitter
what is stage 1 of action potential?
neutrons are negatively electrically charged at about -70mV
what is stage 2 of action potential?
a neuron is stimulated by another neuron, causes excitatory postsynaptic potential, making it more positively charged
what is it called when a neuron becomes more positively charged?
depolarisation
what is stage 3 of action potential?
when neuron has received enough messages to reach the threshold level, an action potential is triggered. this is usually when the neurons charge reaches about -55mV
what is stage 4 of action potential?
action potential sends an electrical impulse along the axon, towards the axon terminals. This triggers the release of a neurotransmitter
what is synaptic transmission?
process where neurotransmitters are released by one neuron that travel across a synapse and are taken up by another neuron
describe the steps of synaptic transmission
action potential is triggered
electrical impulse travels along axon to axon terminals
axon terminals release neurotransmitter molecules into synapse
molecules travel across the synapse towards dendrites of post-synaptic neuron
action potential may be triggered in post-synaptic neuron
some neurotransmitters are reabsorbed by the pre-synaptic neuron in a process called reuptake
supporting evidence for the biological cause of addiction
rat experiments- rats placed in isolated cages and starved. Rats had the choice whether to push a lever to inject heroin. rats would overdose suggesting addiction is biological
opposing evidence for biological cause of addiction
Rat Park experiment by Alexander. lots of space for rats to run around and socialise. there were two water bottles, one with water and the other with morphine solution. all rats would drink normal water, suggesting addiction is not purely biological, but is driven by individuals’ environment
different theory for biological cause of addiction
Freud suggests that addiction occurs due to childhood traumas and conflicts. he suggested that drugs can be used as a way to repress feelings
application for biological cause of addiction
drug replacement therapy which gives a substitute drug that produces similar euphoria and then they are slowly weaned off it
supporting evidence of brain functioning as an explanation for aggression
Charles Whitman killed his family, a dozen others and himself. it was found that he had a tumour pressing on his amygdala, the centre of emotion
opposing evidence for brain functioning as an explanation for aggression
we cannot Whitmans tumour to check for reliability. his aggression may have arisen by other factors in his life
different theory for brain functioning as an explanation for aggression
freud’s psychodynamic explanation- he suggests that aggression is caused by internal drives within the unconscious mind, such as Thanatos (the death instinct) which projects outwards onto others in the form of aggression
application for brain functioning as an explanation for aggression
early intervention- brain scans can be done to detect potential violent offenders. anger management can be provided
what are hormones?
chemical messengers that carry information around the body
what is testosterone?
a hormone linked to aggression
why is testosterone linked with aggression?
males are more aggressive as they have higher levels of testosterone. testosterone is produced in spurts so levels can rise and fall suddenly and have an effect on behaviour
supporting evidence for animal experiments
Wagner et al- castrated rats showed less aggression, when injected with testosterone, they showed aggression levels had risen to pre-castration levels
opposing evidence for animal experiments
lack generalisability to humans as animals lack the cognitive complexities of the human brain e.g. no consequences
different theory for animal experiments
freud’s psychodynamic explanation- aggression is caused by drives within the unconscious mind
application for animal experiments
hormone therapy- MPA decreases functioning of testosterone and lower aggression. however she effects include growth of breasts so many decline
claim of evolution and natural selection
aggression is caused by structure and function of our brain having evolved to serve an adaptive function
define natural selection
where organisms become better adapted to their environment
supporting evidence for natural selection
townsend- women find dominant men more attractive
opposing evidence for natural selection
post hoc- theory been developed to fit the facts
different theory for natural selection
freud- internal drives that project aggression outwards
Application for natural selection
socially sensitive- offenders can’t be held accountable for their actions, as the theory suggests males should be more aggressive
Freud’s claim
aggression is caused by internal drives within the unconscious mind
components of freud
id
ego
superego
what is the id
has no thought of consequences, wants it now
what is the ego
delays the id’s urges. doesn’t understand the difference between right and wrong
what is the superego
becomes aware of societal rules and understands difference between right and wrong
what age does the id develop
at birth
what age does the ego develop
2
what age does superego develop
3-6
what is eros
life instinct
what is Thanatos
self-destruction
supporting evidence for freud
case studies- rich in depth data
opposing evidence for freud
can’t operationalise- they are theoretical concepts that cannot be measured
different theory for freud
biological explanations- aggression is caused by structural differences in the brain
application for freud
catharsis- reduces aggression, sport or video games
claim of hormone theory
aggression is caused by the release of hormones e.g. testosterone
supporting evidence for hormone theory
Wagner et al- castrated rats showed less aggression, but when injected with testosterone again aggression rose
opposing evidence for hormone theory
animal experiments- lack generalisability to humans s we are more cognitively complex
different theory for hormone theory
Freud- aggression is caused by internal drives within the unconscious mind
application for hormone theory
hormone therapy, female hormone MPA lowers testosterone and aggression
what is kety
adoption study
aim of Kety
investigate the genetic basis of schizophrenia by comparing adoptive and biological families of patients with and without schizophrenia
procedure of kety
opportunity sample
recruited from Danish adoption register
34 with schizophrenia
33 without
used Danish family records to identify 459 relatives in total after 4 were dropped
4 psychiatrists used to ‘diagnose’ schizophrenia amongst the relatives
this was done based on their medical records
results of Kety
more signs of schizophrenia in biological family
biological families 5 times more likely to get schizophrenia (8.7% and 1.9%) prevalence
conclusion of kety
there is a genetic component to schizophrenia
Generalisability of kety
large sample of relatives
not generalise to mental health disorders outside of Denmark due to cultural differences
Reliability of Kety
4 psychiatrists to ensure inter-rater reliability
diagnostic criteria used were vague and subjective e.g. borderline
Application of Kety
lead to early diagnosis and early intervention
validity of Kety
diagnostic criteria used were vague e.g. borderline, which limits validity
what is Raine?
classic study
aim of Raine
to see if there is brain abnormality in murderers pleading NGRI compared to non-murderers
procedure of Raine
41 murderers- 41 non murderers used as control
all ppts kept medication free for 2 weeks
ppts injected with a glucose tracer
required to do continuous performance task for 32 mins
given a PET scan
results of Raine
murderers showed lower activity in prefrontal cortex which is an area associated with self-restraint
conclusion of Raine
dysfunction in the prefrontal cortex has been linked to impulsivity and lack of self-control
dysfunction in the amygdala has been linked to lack of fear
generalisability of Raine
sample consists of only 41 murderers
reliability of Raine
standardised procedure e.g. 2 weeks medication free
application of Raine
PET scans can be used to identify those at risk of this behaviour- early interventions
validity of Raine
high control of extraneous variables (2 weeks meds free)
objective measure of brain function using a PET scan
ethics of Raine
ppts may have been persuaded into participation of experiment by lawyers to reduce their sentence
what is brendgen
contemporary study
aim of brendgen
investigate whether physical and social aggression are genetically or socially caused
procedure of brendgen
234 twin pairs recruited from Quebec newborn twin study
ppts were 6 yrs old
teachers completed questionnaires, rating children on a 3 point scale on 6 statements e.g. gets into fights
3 questions about social, 3 questions about physical aggression for teachers
children peers shown photos of classmates and asked to circle photos of 3 children who best fit statements e.g. gets into fights.
2 statements of physical, 2 statements of social for children
results of brendgen
correlation between physical aggression ratings between identical twins was twice as high as non-identical twins (MZ and DZ)
roughly 50-60% of physical aggression can be explained by genetic causes, only 20% of social aggression can b explained by genetics
conclusion of brendgen
children who are physically aggressive are more likely to be socially aggressive, but not the other way round
as children age, they show more social aggression
generalisability of brendgen
large sample of 234 twin pairs
ppts were 6 years old, can’t generalise to older peoples aggression
social aggression develops fully at 8 yrs
reliability of brendgen
standardised 3 point scale and the same 6 statements given to teachers e.g. gets into fights
application of brendgen
early intervention programmes to prevent social aggression
validity of brendgen
objective, 3 point scale means aggression ratings are objective and quantitative
