nervous system functioning

central nervous system (spinal cord)

recieve sensory info from the body (via the pns) and carry to the brain for processing
recieve motor info from the brain and carry it to relevant parts of the body (via the pns)

spinal reflex

an unconcious automatic response controlled solely by neural circuits in the spinal cord

central nervous system (brain)

processes info and coordinates responses through a series of networks

peripheral nervous system

comprimised of muscles, organs, and glands
sends sensory info to the cns, recieves motor info from the cns

somatic nervous system

network of neurons within the body that transmit info from receptor sites to the CNS and then carry info to the muscles to initiate voluntary movement

autonomic nervous system

a network of neurons that carry info between the CNS and the organs and glands to ensure they are regulated and without concious awareness

sympathetic nervous system

the SNS activates internal muscles, organs, and glands to prepare the body for vigorous activity to deal with a stressful or threatening situation

• adrenal glands secret adrenaline and noradrenaline

• heart rate increases

• dilated pupils

parasympathetic nervous system

the PSNS helps to maintain internal body environment in a steady, balanced state of normal functioning and has a counterbalancing effect to the SNS

restores body to a state of calm

• maintains homeostasis

• pupil constriction

• heartrate decreases

enteric nervous system

dedicated to the functioning of the gastrointestinal (digestive) tract

concious response

response to a sensory stimulus that involves awareness

unconcious response

response to a sensory stimulus that doesn’t involve awareness

s-a-m-e

afferent pathways carry sensory info up to the brain

efferent pathways carry motor info from the brain, travelling though the spinal cord and via spinal nerves to destination

fight-flight-freeze

dependent of the likelihood of survival in each situation and is considered an adaptive response as it aids survival

symptoms of freeze response

can be both adaptive and non-adaptive

• body movements and vocalisations stop

• tense muscles collapse and become still

neurotransmitters

chemical substances that bind to specific receptor sites on the post-synaptic neuron

• GABA

• glutamate

neuromodulators

changes the reactivity of receptors to another type of neurotransmitter to enhance their excitatory/inhibitory response

have broader effects and are more long-lasting than neurotransmitters

• dopamine

• serotonin

GABA

inhibitory neurotransmitter which reduces the likelihood of the post-synaptic neuron to fire an action potential

regulates post-synaptic activation and prevents over excitation of neurons

glutamate

excitatory neurotransmitter which increases the likelihood of the post-synaptic neuron firing an action potential

has an important role in learning and memory by strengthening synaptic connections

serotonin

a neuromodulator which has roles in mood, emotional processing, appetite, and pain perception

is linked to depression, anxiety, and sleep disorders

is only inhibitory

dopamine

a neuromodulator which has roles in the experience of pleasure, motivation, reward based learning, and addiction

both inhibitory and excitatory

neuroplasticity

the brains ability to change istelf as a result of experience

long-term potentation

the long-lasting and experience dependent strengthening of synaptic connections that are regularly activated

long-term depression

the long-lasting and experience dependent weakening of synaptic connections between neurons that are not adequately activated

sprouting

the ability of dendrites or axons to change over time in response to experience

rerouting

the ability of a neuron that is connected to a damaged neuron to create an alternate synaptic connection

pruning

the elimination of synaptic connections that are not adequately activated

proliferation

to enhance or create, making more neurons

migration

move to areas where needed the most

circuit formation

if strong, then myelinate, if weak, then prune

gut-brain axis

a bi-directional communication link between the CNS and the ENS

gut microbiota

living organisms that live in our gastroinestinal tract and maintain gut health and functioning

vagus nerve

most important nerve in the PNS, which 80-90% of nerve fibres responsible for conveying info from the gut to the brain

largest storage space for serotonin (95%) and plays a role in mood, immune response, and digestion