Biopsychology Flashcards
What is the primary means of communication in the nervous system?
Neurons
What do dendrites do?
carry nerve impulses towards the cell body
What does the axon do?
carriers nerve impulses away from the cell body
What is the myelin sheath?
insulating layer on axon that speeds up electrical transmission
What are the nodes of ranvier?
gaps in myelin sheath that speed up electrical transmission
What is the axon terminal?
End of the axon that send impulses to the next neuron across the synapse
How do neurons pass a message?
When at rest there is a negative charge outside the cell and a positive charge inside the cell
When the cell fires, a chemcal process reverses the cahrge and an action potential occurs. An electrical impulse moves down the neuron along the axon
What are the 3 types of neuron?
Sensory, motor and interneuron
What does the sensory neuron do?
carries info from sense to CNS
What does the motor neuron do?
carries info away from CNS to muscles or glands
What do interneurons do?
connect neurons
What is the synapse?
A specialised gap between the end of one neuron and the dendrites of the next
How are signals transmitted to adjacent neurons?
Using neurotransmitters in synaptic transmission
What are neurotransmitters?
Brain chemicals that affect cognitive processes and behvaiour
Name one neurotransmitter and its role
Dopamine, involved in emotional arousal, pleasure and voluntary movement. too much is thought to be responsible for schizophrenia
What happens in an excitatiry synapse?
neurotransmitter makes recieving neuron more likely to fire and pass onb electrical impulse
What happens in an in an inhibitory synapse?
neurotransmitter makes receiving neuron less likely to fire and pass on electrical impulse.
Describe the process of synaptic transmission.
- nerve impulse travels down terminal and arrives at pre-synaptic terminal
- vesicles release their neurotransmitter across the synapse
- the chemical binds to receptor sites on adjacent neuron
- enzymes released to break down excess neurotransmitter or they are reabsorbed by the synaptic terminal
- Vesicles are replenished with neurotransmitter
What two sections is the nervous system divided into?
Peripheral nervous system and CNS
What makes up the CNS?
brain and spinal cord