Chapter 2 (Nervous System) Flashcards
role of the nervous system
- reception of sensory information
- processing of received information
- response of received information
nervous system flow chart
nervous system
central ns peripheral ns
brain spinal cord somatic autonomic
afferent. sympathetic.
efferent parasympatheic
role of central nervous system
brain - processing system, sent here processed and sent out
spinal cord - group of nerves that connect the brain to other body structures (how brain communicates with body)
role of peripheral nervous system
- carry sensory info to spinal cord
- carry motor info from spinal cord
- divided into 2 part (somatic and autonomic)
role of somatic nervous system
- network of nerves that carries sensory info from receptor sites to the CNS via sensory neurons
- also carries motor info from the CNS to the voluntary
skeletal muscles via motor neurons - use SAME
role of autonomic nervous system
- connects the central NS to the body’s involuntary muscles, internal organs and glands
- 2 divisions (sympathetic and parasympathetic NS)
- increased heart rate, pupils dilate, sweating
role of sympathetic nervous system
- increasing autonomic arousal
- fight, flight
- release hormones into the bloodstream (adrenaline and noradrenaline)
role of the parasympathetic nervous system
- decreasing autonomic arousal
- maintains your body’s normal level of functioning
- also acts to restore homeostasis after the activation of the sympathetic NS
conscious response
you notice is cold outside so you go inside and get a jacket
unconscious response
- the body’s response to the cold is to start shivering
- involuntary response was made without awareness
spinal reflex
- response to stimuli that occurs unconscious and involuntary
- is a somatic nervous system response
- the message doesn’t get sent to the brain until after the response
- sensory info about the situation (e.g hot pan) are received by sensory receptors and then sensory neurons carry and travel along afferent pathways towards the spinal cord, interneurons communicate between sensory and motor neurons and send a message to the moto neurons that then travel back along a efferent pathways and activate the muscles/response
neural transmission
- lock and key neural transmission
- communicate by releasing neurochemicals into the synaptic gap
axon - transmits the action potential
axon terminal - releases the neurochemical
dendrites - contain receptors which neurochemical bind
structure & function of the neural synapse
- form a connect with the synaptic gap
- between the pre synaptic neuron (axon terminal) and the post synaptic neuron (dendrites)
- stored in sac (vesicles)
- when action potential reaches the axon terminal it with cross the synaptic gap
- binds with the receptor site on the dendrite
- trigger response in neighbouring neuron
neurotransmitter exitatory
- increase the chance of action potential forming in post synaptic neuron
-GLUTAMATE
effect - increase the chance of action potential firing
role - important in the role of learning and memory
- forms and strengthens synaptic connections
neuro transmitter inhibitory
- decreases the chance of action potential forming in post synaptic neuron
- GABA
effect - decrease the chance of action potential firing
role - preventing overexcitation
- reduces anxiety
neuromodulator dopamine
pathway - mid-brain and ventral tegmental area
effect - can have both excitatory and inhibitory effects on the post synaptic neuron
role - coordinating voluntary motor movement, motivation
neuromodulator serotonin
pathway - masses of neurons in the brainstem
effect - has a inhibitory effect on the post synaptic neuron
role - mood regulation, sleep and wake cycle
define synaptic plasticity
the ability of synaptic connections to change from experience, can be negative or positive
mechanisms of plasticity
sprouting - dendrites and axon terminals sprout new growth, allows for new synapses to form
rerouting - alternative synaptic connections can be formed, due to neurons that have damaged connections
pruning - synaptic connects that are not regularly activated can be lost or removed (cut away)
structural changes to LTP AND LTD
LTD - decreased number of receptor sites on dendrites on post synaptic neuron
- pruning
- loss of synaptic connections
LTP - increased number of receptor sites on dendrites on post synaptic neuron
- sprouting
- increase number of synaptic connections
role of long term depression (LTD)
- long lasting and experience dependent weakening of synapses
- are not regularly activated
- will occur in response to weak use of synapse
role of long term potentiation (LTP)
- long last and experience dependant strengthening of synapses
- are frequently activated
- will occur in response to frequent use of synapse
