nervous system Flashcards
(28 cards)
function of nervous system
receives information, process information and coordinates a response
what is within the nervous system
Peripheral NS(somatic(sympathetic and parasympathetic) and autosomatic) and central NS(brain and spinal cord)
function of central nervous system
- sends and receives messages to and from the PNS
function of the brain
- processes sensory info
- coordinates a response to that information
CNS
function of spinal cord
- connects the brain to the PNS
- receives sensory info from PNS and sense to the brain(up to spinal cord)
- receives motor information from the brain and sends it to various parts of the body using the PNS(down the spinal cord)
CNS
function of Peripheral nervous system
- made up the entire network oF nerves outside the CNS
-carries sensroy information to the CNS
-carries motor information from CNS
Somatic Nervous System
-Initiates skeletal movement
* Carries sensory information to the CNS (neural
pathways are afferent/towards)
* Carries motor information from the CNS (neural
pathways are efferent/away from)
Autonomic nervous system
Connects CNS to internal organs and
glands
* Self-regulating/automatic (not under
voluntary control)
* Regulates the muscles controlling
organs (known as visceral muscles)
sympathetic nervous system
- Prepares the body for action
- Fight-flight-freeze response
- Triggered by a stressor/fear stimulus
- Releases hormones such as adrenaline,
from the adrenal glands - Heart rate and breathing rate increases
parasympathetic
- decreases visceral muscles
- Calms the body after action
- Dominates the sympathetic nervous
system most of the time (during routine,
everyday activities) - Takes longer to return the body to its
normal state as it has to remove
hormones from the bloodstream
conscious response
A conscious response to a sensory stimulus is a reaction that involves awareness and is
voluntary. It usually happens after you have paid attention to the stimulus
unconscious response
An unconscious response to a sensory stimulus is a reaction that doesn’t involve awareness. It
is involuntary and automatic. These are generally controlled by the autonomic nervous system,
and include functions such as blinking, or your heart beating. Sometimes they are reflexive
responses, when there isn’t enough time to make a conscious response
spinal reflex
A spinal reflex is an unconscious and involuntary response that occurs automatically to certain
stimulus, without any involvement of the brain. This allows for a faster reaction time in
potentially harmful situations
neurons
A neuron is an individual nerve cell that is specialised to receive, process and
transmit information to other cells in the body
parts of neurons
dendrites, axon, myelin, axon terminals, terminal button
synaptic gap
The synaptic gap is a tiny gap
(about 500 times thinner than a human hair)
between the dendrites of one neuron and the
terminal buttons of another neuron. It is part
of the synapse, which is where
communication between two neurons occurs
neurotransmitter
neurotransmitters are a chemical substance produced by a neuron that carry a message to
other neurons or cells. When carrying a message to another neuron, neurotransmitter works by
attaching themselves to receptor sites of postsynaptic neurons. The neuron that releases the
neurotransmitter is called the presynaptic neuron
glutamate
glutamate is the main excitatory neurotransmitter in the CNS. This means that glutamate
enhances information transmission by making postsynaptic neurons more likely to fire. It is
associated with increases in learning and memory
gaba
GABA is the main inhibitory neurotransmitter in the CNS. It works throughout the brain to make
postsynaptic neurons less likely to fire
agonists
Substances that increase the receptiveness of the dendritic
receptors to a particular neurotransmitter are known as agonists
Dopamine
Dopamine is a neurotransmitter that is important for balance,
movement, pleasure + rewarding behaviours. It is a
neuromodulator, meaning that it can lead to both excitatory +
inhibitory effects
* can be released from a neuron far from its receptor site
* influence effects of other chemical messengers
Dopamine
Dopamine is a neurotransmitter that is important for balance,
movement, pleasure + rewarding behaviours. It is a
neuromodulator, meaning that it can lead to both excitatory +
inhibitory effects
* can be released from a neuron far from its receptor site
* influence effects of other chemical messengers
Serotonin
- Serotonin is a neurotransmitter (that also acts as a hormone) and
is important for mood and sleep - the ‘feel-good’ hormone
neural plastcity
Neural plasticity is the ability of the brain’s neural structure or function to be changed
throughout the lifespan, generally through experience. Neural plasticity is the basis of learning
and memory
