Biopsychology Flashcards
2 sub systems of the nervous system
- central nervous system
- peripheral nervous system
Central Nervous System
- Brain and spinal cord
Peripheral Nervous System
- autonomic nervous system
- somatic nervous system
Autonomic Nervous System
- controls involuntary vital functions in the body such as breathing, heart rate, digestion, sexual arousal and stress responses
- Is divided into the sympathetic and parasympathetic nervous systems
- Sympathetic: physiologically aroused –> increased heart and breathing rate, inhibits digestion and inhibits saliva production
- –> prepares for action/stress
- Parasympathetic: physiologically resting –> decreases heart and breathing rate, stimulates digestion and stimulates saliva production
- –> clams body and helps conserve energy
Somatic Nervous System
- carries sensory info from sensory organs to CNS
- controls muscle movement
- (voluntary movement)
Neurons
> process and transmit messages through electrical and chemical signals
Sensory Neurons
> carry messages from the PNS to the CNS
long dendrites
short axons
Relay Neurons
> connect sensory Neurons to Motor or other relay Neurons
short dendrites
short axons
Motor Neurons
> connect the CNS to effectors such as muscles and glands
short dendrites
long axons
Neurons: Cell Body (soma)
> contains nucleus which contains genetic material
Neurons: Dendrites
> carry nerve impulses from neighbouring Neurons towards the cell body
Neurons: Axons
> carry impulses away from the cell body down the neuron
Neurons: Myelin sheath
> fatty layer that covers and protects the axon and speeds up electrical transmission of the impulse
Action potential
> neuron testing state = negatively charged compared to outside
neuron is activated by stimulus —> insideof cell becomes positively charged for a split second
causing an action potential
this creates an electrical impulse that travels down the axon towards the end of the neuron
Synaptic transmission
> each neuron is separated from the next by synapses
the synapse includes:
- the space between: synaptic gap
- presynaptic terminal
- post synaptic receptor site
> signals WITHIN Neurons = electrical
signals BETWEEN Neurons = chemical by synaptic transmission
> electrical impulse reaches presynaptic terminal –> triggers the release of neurotransmitters from synaptic vesicles
> neurotransmitters (chemicals) diffuse across synaptic gap
> then reaches the post synaptic receptor sites (dendrites)
chemical message is converted back to electrical impulse and the transmission begins again for the next neuron
Neurotransmitter
> chemicals that diffuse across the synapse to the next neuron
Excitatory Neurotransmitter
> increases the likely hood that a neuron will fire and pass on the electrical impulse
Inhibitory Neurotransmitter
> decreases the likely hood that a neuron will fire and pass on the electrical impulse
Summation
> determines whether or not a postsynaptic neuron fires
excitatory and inhibitory influences are summed
> excitatory = sum of influences causes neuron to become positively charged - action potential is created - then released
—> must reach a threshold in order for action potential to fire
Localisation of function
> different area of the brain are responsible for different behaviours
cerebral cortex
> outer layer of both hemispheres
grey matter
each hemisphere is split into: frontal lobe, parietal lobe, occipital lobe and temporal lobe
Frontal lobe
> the back has the motor area which controls voluntary movement in the opposite side of the body
> Damage = loss of control over fine movements