1. Nervous System
• Central Nervous System
-Consists of brain and spinal cord
-Controls behaviour and regulates
physiological processes
-Spinal cord function is to relay
information between the brain and the
rest of the body.
• Peripheral Nervous System
-Somatic nervous system : controls voluntary functions and carries sensory and
motor information to and from the CNS.
-Automatic nervous system: which controls involuntary bodily functions
-Automatic nervous system has 2 branches:
v -Sympathetic Nervous System, fight or flight response, noradrenaline,
increases HR, slows down non-emergency functions such as digestion.
(speed up).
v -Parasympathetic Nervous System, rest and digest, acetylcholine, slows HR,
BR, reduces blood pressure and restores digestive processes back to
normal. (slow down).
2. Neurons and Synaptic Transmission
• 3 types of neurons:
Sensory
-Carry impulses from sensory receptors to CNS
Relay
-Connects sensory neurons and motor neurons, found in the CNS
Motor
-Carry nerve impulses to the muscle to allow movement to occur
-Nerve impulses, known as action potential and travel along the axon
, Biopsychology
• Synaptic Transmission
1. -Arrival of action potential at end of the axon triggers release of
neurotransmitters by exocytosis.
2. -Neurotransmitters diffuse across the gap and bind to receptors on post-
synaptic neuron, binding to specialised receptors and activated by the
neurotransmitter. Then generate an excitatory or inhibitory effect :
3. -Neurotransmitters can be excitatory, such as acetylcholine, or
inhibitory, such as serotonin
-Excitatory, make post-synaptic neuron more likely to fire
-Inhibitory, make post-synaptic neuron less likely to fire
3. The Endocrine System
-Glands secrete hormones into the bloodstream.
-Glands are self-regulated through negative feedback, known as homeostasis.
-Hormones regulate the activity of cells or organs in the body, they stimulate
response in target area/cells.
• Pituitary Gland
-Controlled by hypothalamus
-Regulates many of the bodies main functions by releasing hormones that
control many other endocrine glands
-Releases ACTH as a response to stress.
• Adrenal Gland
-Adrenal cortex - produces cortisol, which increases during stress
-Adrenal medulla - releases adrenaline and noradrenaline, preparing the body
for flight or flight
4. Fight or Flight Response
-Enables us to react quickly to life-threatening situations
-Stress response activated by amygdala, which associates sensory input with
emotions such as fear and anger, amygdala sends impulse to hypothalamus.