Transcript The nervous system

The nervous system
From the perspective of
contemporary psychology
A survey of the
nervous system
Within the broad heading of the Nervous
System we find many component systems and
subdivisions
The first are:
a) The Central Nervous System –
the brain and the spinal cord, and
b) The Peripheral Nervous
System – bundles of axons connecting the
spinal cord and the rest of the body.
The spinal cord
A rope of neural tissue that runs inside the
hollows of the vertebrae from just above
the pelvis into the base of the skull
Connected to both sensory ( pain, touch,
and pleasure) and motor ( contract and
relax muscles) neurons
Facilitates reflexes - rapid, involuntary
responses to stimulus
the peripheral
nervous system
Divides into :
a) the Somatic Nervous System –
nerves which communicate with the skin
and muscles and
b) the Autonomic Nervous System –
nerves which control the involuntary
muscles, internal organs (heart, lungs,
stomach, etc.) and glands
The autonomic
nervous system
Two divisions:
1) Sympathetic – prepares your body for
action, fight or flight
blood flows to muscles
epinephrine increases heart rate
lungs pull in more oxygen
sweat forms for cooling
2) Parasympathetic – returns your body
to its resting state, conserves energy
heart rate slows
epinephrine cut off
lungs relax
stomach resumes
digestion
The endocrine
system
A set of glands that produce and release
hormones
These hormones influence thoughts,
behaviors and actions
Transmitted through the blood
Have a global effect as compared to the
local effect of neurotransmitters
Include the hypothalamus and pituitary
Hormones of note
Melatonin – aids sleep, from pineal gland
Oxytocin – the cuddle hormone, from
pituitary gland
Cortisol, Epinephrine, etc.– arousing,
from adrenal glands
Sex hormones (Testosterone, Estrogen,
etc. – differentiate the sexes (and much
more), mostly from the gonads