Biopsychology Flashcards
What are exogenous zeitgebers?
they are environmental cues which regulate body clocks
What are the examples of exogenous zeitgebers?
light
social cues
How is light an example of an exogenous zeitgebers?
- receptors in the SCN are sensitive to change in light levels
- and the uses this info to synchronise the activity of the body organs and glands
What does the zeitgebers do?
resets the body’s internal body clocks every 24 hours
What are endogenous pacemakers?
internal
What are the examples of endogenous pacemakers?
pineal gland
SCN
How is SCN an example of an endogenous pacemakers?
controls sleep/wake cycle (circadian rhythm)
has control over body clocks
neurons in SCN synchronise together, so that they target neurons in sites of the body which receive time-coordinated signals
How is pineal gland an example of an endogenous pacemakers?
SCN sends signals to the pineal gland
which then increases the production of melatonin at night and then decrease in the morning
melatonin makes you fall asleep as it inhibit brain mechanisms that promote being awake
What is an circadian rhythm?
24 hours (one day)
What is an infradian rhythm?
more than one day
What is an ultradian rhythm?
under a day
Draw the nervous system
-
What does the spinal cord do?
relays information between the brain and the rest of the body
What does the brain do?
has four areas - cerebrum, cerebellum, diencephalon and brainstem
What is the somatic nervous system?
responsible for carrying sensory and motor information to and from the central nervous system
What is the autonomic nervous system?
controls involuntary actions
What are the 2 things which make up the central nervous system?
spinal cord
brain
What are 4 things which make up the peripheral nervous system?
somatic nervous system
autonomic nervous system
sympathetic nervous system
parasympathetic nervous system
What is the sympathetic nervous system?
helps up deal with emergencies - fight or flight - it increases heart rate etc.
What is the parasympathetic nervous system?
relaxes the body after the emergency - slows heart rate back down etc.
Draw the structure of a neuron
-
What are the 3 types of neurons?
motor
relay
sensory
What are sensory neurons?
carry nerve impulses from sensory receptors to the spinal cord and the brain
What are relay neurons?
allow sensory and motor neurons to communicate with each other
What are motor neurons?
located in the CNS, form synapses and release neurotransmitters that trigger a response from muscles
Draw the synaptic transmission
-
Explain the synaptic transmission
1 - electrical impulse (Action potential) arrives at the end of axon
2 - synaptic vesicles which contain chemical messenger
3 - impulse reaches the vesicles which secrete the chemical messengers which help transfer the impulse
4 - neurotransmitters carry the signal across the synapse
5 - which bind to the receptors
What is summation?
the adding up of positive and negative post-synaptic potentials
What are excitatory neurotransmitters?
increase the chance that an excitatory signal is sent to the postsynaptic cell, which is then more likely to fire
What are inhibitory neurotransmitters?
decreases the chance of that neuron firing - usually responsible for calming the mind and body and sleep
Give an example of an excitatory neurotransmitter?
noradrenaline
Give an example of an inhibitory neurotransmitter?
GABA
Why do excitatory neurotransmitters mean a neuron is more likely to fire?
because when a excitatory neurotransmitter binds to the postsynaptic receptor it causes an electrical change in the membrane of that cell, resulting in EPSP (excitatory post-synaptic potential)
Why do inhibitory neurotransmitters mean a neuron is more likely to fire?
when a inhibitory neurotransmitters binds to the postsynaptic receptor it results in IPSP (inhibitory post-synaptic potential)
What are the 3 types of glands?
- endocrine
- pituitary
- adrenal
What is the endocrine system?
is a network of glands throughout the body that secrete chemical messengers (hormones) around the body
What does the endocrine gland do?
produce hormones which regulate the activity of cells and organs
What does the pituitary gland do?
‘master gland’ - produces hormones which stimulate the production and release of other hormones. Is controlled by the hypothalamus
What does the adrenal gland do?
adrenal cortex produces cortisol and adrenal medulla produces noradrenaline
What is cortisol responsible for?
stress response
What is noradrenaline responsible for?
fight or flight
Draw the structures which are in the fight or flight response
-
What does the amygdala do in the fight or flight response?
associates sensory signals (e.g senses) with emotions which are linked to flight and fight like anger and fear. It then sends a distress signal to the hypothalamus
What are the 2 systems used when the body is responding to stressors?
- acute
- chronic
What is an acute response?
sudden
What is a chronic response?
ongoing
What are the steps for response to acute stressors?
- sympathetic nervous system (SNS) is triggered
- SNS sends a signal to the adrenal medulla
- which releases adrenaline into the bloodstream
- adrenaline causes physical changes to the body e.g heat beats faster
- adrenaline also causes the release of glucose
- when threat has passed, the parasympathetic nervous system relaxes the body again
What are the steps for response to chronic stressors?
- if threat is ongoing then the hypothalamus activates the stress response system called HPA axis
- hypothalamus releases CRH, which is a chemical messenger
- CRH causes the pituitary gland to produce ACTH, which targets the adrenal glands
- ACTH stimulates the adrenal cortex to release cortisol
- feedback
What does the HPA axis consist off?
hypothalamus
pituitary gland
adrenal gland
What is localisation of function?
refers to the belief that specific areas of the the brain are associated with specific cognitive processes
What are the different areas of the brain mentioned in localisation of function?
motor areas somatosensory areas visual centres auditory centres language centres
What does the motor cortex do?
responsible for voluntary motor movements
What are the differences of both hemispheres?
-
What are the similarities of both hemispheres?
- both have a motor cortex
- both have a somatosensory cortex
What are the differences of both hemispheres?
- broca’s area in left hemisphere
- wernicke’s area in right hemisphere
What are the similarities of both hemispheres?
- both have a motor cortex
- both have a somatosensory cortex
- both have visual centres
- both have auditory centres
Where is the motor cortex found?
frontal lobe
What is the visual centre?
processes visual information
Where is the visual centre found?
occipital lobe
What is the auditory centre?
processes auditory information
Where is the auditory centre found?
temporal lobe
What is Broca’s area?
is related to speech production
Where is Broca’s area located?
frontal lobe in the left hemisphere