biopsychology Flashcards
What does the CNS consist of?
brain and spinal cord
What are the two main functions of the CNS?
- control of behaviour
- regulation of the body’s physiological processes
how does the CNS carry out its functions?
- the brain receives information from the sensory receptors
- brain sends messages to the muscles and glands of the body in response
what are the four areas of the brain?
cerebrum
cerebellum
diencephalon
brain stem
what is the cerebrum?
- largest part of the brain
- has four lobes
- is split into two halves called hemispheres
what is the functional the cerebellum
- responsible for motor skills
- balance and coordinating muscles to allow precise movements
what does the diencephalon contain?
thalamus
hypothalamus
what does the thalamus do
regulates consciousness, sleep and alertness
what does the hypothalamus do
regulates body temperature, stress response and hunger and thirst
what is the main function of the spinal cord
- relays information between the brain and the rest of the body.
- allows the brain to monitor and regulate bodily processes (digestion, breathing, voluntary movement)
what does the PNS consist of
the nervous system throughout the rest of the body (not the brain or spinal cord)
how does the PNS work
transmits messages via neutrons (nerve cells) to and from the CNS
what are the two divisions of the PNS
somatic nervous system
autonomic nervous system
what is the function of the somatic nervous system
- controls voluntary movements and is under conscious control.
- connects the senses with the CNS
- has sensory AND motor pathways
- controls skeletal muscles
- CONTROLLED BY the motor cortex
what is the function of the autonomic nervous system
- involuntary control
- ONLY has motor pathways
- it controls smooth muscles and the internal organs and glands of the body
- CONTROLLED BY the brain stem
what are the two divisions of the autonomic nervous system
sympathetic nervous system
parasympathetic nervous system
when is the sympathies nervous system activated and what happens
- activated when a person is stressed
- heart rate, breathing increase. digestion stops
- salivation reduces, pupils dilate
- blood is diverted from the surface on the skin (fight or flight)
when is the parasympathetic nervous system activated and what happens
- activated when the body is relaxing and conserving energy
- heart rate, breathing reduce. digestion starts
- salivation increases, pupils constrict
what are neurons
specialised nerves cells that move electrical impulses to and from the CNS
what is the cell body
control centre of the neuron
what is the nucleus
contains genetic material
what do dendrites do
received an electrical impulse (action potential) from other neurons or sensory receptors
what is the axon
long fibre that carries the electrical impulse from the cell body to the axon terminal
what is the myelin sheath
insulating layer that protects the axon and speeds up the transmission of the electrical impulse
what are schwann cells
make up the myelin sheath
what are the nodes of ranvier
gaps in the myelin sheath. they speed up the electrical impulse along the axon
how do neurons differ?
structure
location
function
where are sensory neurons found
sensory receptors (eyes, ears, skin etc)
how do sensory neurons work
- sensory neurons convert information from sensory receptors into electrical impulses
- carry electrical impulses from the sensory receptors to the CNS via PNS
- when impulses reach the brain they are converted to sensations (heat/pain) so that body can react appropriately
- some sensory impulses terminate at the spinal cord
what do sensory neurons allow us to do
allows reflexes to occur quickly without the delay of sending impulses to begin
where are motor neurons located
in the CNS
but project their axons outside of the CNS