Biological Flashcards
key assumptions of biological psychology
all behaviour is determined by biological factors
behavioral and psychological develop,ent is assumed to be based on changes in the brain and general bilogy
genes influence behaviour
the cns
the brain - draws together information from all over the body and sends information back out to the body in response
the spinal cord - contains the nerves that carry messages between the brain and the body
pns branches out from the spinal cord
the role of the cns in human behaviour
the cns acts as an information processing and control centre fro information we receive and responses that we make in our environment
frontal lobe
desicion making
problem solvig
planing
parietal
reception and processing od sensory information from the body
occipital
vison
temporal
memory
emotion
hearing ad language
the prefrontal cortex
part of the rontal lobe
executive functions
inhibiting innapropriate responses desision making and motivational behaviour
the limbic system
complex system of structures and nerves
linked to instinct and mood
thalamus
hippocampus
amygdala
hypothalamus
thalamus
relays information from the five senses to relevent parts of the cortex
amygdala
emotions such as aanger and fear linked
if our senses perceive a threat thos area is stimulated
fight or flight response
hippocampus
key role in memory formation
linked to emotions
evolution - remembering what things frighten us
hypothalamus
regulates bodily functions by stimulating the release of hormones
neurons
specialised cells
communicate with other cells
atapt as we have new experiences
axon
dentrites
cell body
nucleus
axon hillovk
mylean sheath
nodes of ranveir
synapse
the role of neurns in human behaviour
they are the basis of all behavior i that any time we think feel or do something thousands of neurons are communicating
the role of neurotransmittetrs in human behaviour
neurotransmitters are chemical messangers that take information around the brain . they are then released from the presynaptic neuron into the synaptic cleft after an action potential
they then stimulate the post synaptic neuron and assist that neuron to create its own avtion potential . Altough , they can also inhibit the post synaptic neiron making it less likley to produce and action potentoal
neurostansmitters alow neurons to communicate with one another
seretonin
inibits violent tenancie
decreases our worries
dopamine
noradrenaline
synaptic transmission
- an action potential moves dwon the presynaptic neuron and causes the vesicles filled with neurotransmitters to move close to the terminal membrane
2.the vesicles fuse with the terminal membrane in a process called exoytosis this causes the neurotransmitter to be released into the synaptic cleft - te neurotransmitter binds with potein receptors in the post synaptic neuron and the presynaptic neuron receptors in both
activation of the receptors on the post synaptic neuron causes the post synaptic neuron to increase the probability of producing an ation potential
activation of the receptors on the presynaptic neuron causes the presynaptic neuron to stop reasing neurotransmitters . - once the neurotransmitter is released into the synaptic cleft it is removed by one of the three processes
reuptake - taken back into the presynaptic neuron
broken down - by enzymes in the synaptic cleft
diffusion - disperesed away from the synaptic cleft
evaluation of synaptic transmission
^ research uses brain scanning eg pet scans so high scientific credibility e.g pet scans have founf dfferencesin synaptic receptor sites
however pet scans do not give microscopic detail on synaptic transmission .
* studying animals - difficult to generalise eg van den over 2008
* individul differences - not taken into account as it assumes everyones synaptic transmission in the same way
recreational drugs
reward pathways in the brain
drugs target what is known as reward pathways
circuits of structurs and erves that are linke to the acticities of specific neurotransmitters in particular dopamine
dopamine pathways
actovated by natural rewarding pathways such as having sex or eating food
stimulates the release of normal levels of dopamine in certain areas of the brain including the ucleus accumbens and the ventral tegmental area in the limbic system
messages are sent to the frontal cortex and we experience pleasurable feeligs
make us more likley to repeat the behavior
how recreational drugs wrk
alering neuro transmission in one specific ststem the dopamine system
increase the levels of dompamine in the limbic system and the VTA
structures in the nucleus accumbens are assosiated with plearsurable experiences and are considered to be part of reward systems in the brain
drugs act t prolong and intesify the activity in the reward system by ensuring that an increase in dopamine levels continously excites the post synaptic neurons within the system so that they keep firing .
ways drugs affect synaptic transmission by
increasing the amount of dopamine released into the synaptic cleft blocking the presynaptic transporters so that reuptake is stopeed and more remains in the synaptic cleft
stopping the action of enzymes that would normally breakdown the neurotransmitter so more dopamine is left in the sunaptic cleft
cocaine
it disrupts the. ormal funtioning of the dopamine rward pathways in the brain
works by blocking the transporter receptors on the presynaptic dopamine neurons in the ventral tegmental area
as a result the presynaptic neurosdo not ruptake dopamine , theefore dopamie remains there for longer
prolongs and intensifies the stimulation of the ost synapticneuron
europhoric feelings
drug addiction
the brain is a self rgulating system and reacts to this overproduction of dopamine by rducing how much dopaine it naturally produces
this plactisity of the brain allows it to adapt to the changes imposed on it by drugs
but the brain will now longer operate properly without the drug
brain has less dopaine - dysphoria
the motivation to self administer the drug is overpowering to reduece feelings of sysphori and re experience euphoria
leads to repeated use of the drug wih causes the brain to further down regulate production of dipamine
so tolerance is built up for the drug
needs greater dses
addicted
hormones
hormones are chemical substances produced by a specialised gland and transported in the blood to stimulate specific cells or organs into action
chemical messangers
secreted by glands wich are colllectively named th endocrine system
controlled by the hypothalamus
once they have been secreted into the bloodstream they reach a perticular destination
binding with target cells
hormones take longer to work but have a longer term influence
the role of hormones in human development
1- in the womb - brain is influenced by reproductive hormones oestrogen , progerterone , testosterone
impact sex differences causing brains to develop slighly differently
2- during early childhood - stressful environment - they relese the stress hormone cortisol wich represses the imune system and stimulates the automati nervous system resulting in high levels of arousal
the regions of the brain involved in fear anxeity and impulse resonses may overproduce neural conections while aras assosiated with reasoning and planny may produce fewer
3 - puberty and adulthood - hormone imbalences may make a person more suseptable to depresion anxeity alcoholism and even drug abuse
evaluation of hormones to explain human behaviour
^ scientificlly redible
standardised measurmnts eg measuring hormones using blood tests
lots of suporting evidence - reliable
- ethial issues - cannot manipulate hormone levels meaning research is oftern correlational
cause and effect can not be infferred
practical problems
longitudinal research
reductionist
evolution definition
the gradual development of different kinds of living organisms from earlier forms throughout histor of the earth
natural selection
a gradual process by wich hereditable trats become more or less common in an environment . the organisms that have traits better adapted to survival in their environment are healthier live longer and reproduce more frequently
evolution summary
individuals in a species show a wide range of variation caused by random genetic mutations
the environment also has a wide range of variation
individuals with characteristics most well adapted to the environment are more likley to survive and reproduce and pass their genes - survival of the fitesst
the characteristics that allow these individuals to be sucessful are inherited by their offspring
individuals who are poorly suited are less likley o survive and reproduce so less liley genes will be passed on
over time the species will graduallu evolve to the characteristic that enabe survival in the environment
Aronsons 1997 definition of agression
an intentional action aimed at doing harm or causing pain . the action may be physical , verbal it might suceed in its goal or not
the prefrontal cortex - agression
rgulating agression
control agressve impulses
stop us from automatically reacting to threats - allows us to think
when we experience
