L1 - Intro to Sensory Motor Systems and Methods Flashcards
What is needed to copy another person’s motor actions?
Activation of the motor system, which is involved in action observation as well as action production.
Why do animals have nervous systems?
For learning and adaptable behaviour (and movement)
What does the sea squirt do that provides evidence for the nervous system being responsible for action and movement?
It attaches to a sedimentary rock at the bottom of the sea and digests it’s own nervous system.
Which part of a neuron is responsible for the input of information?
Dendrites
Which part of the neuron is responsible for the output of information?
Axon
Which part of a neuron is the main cell body?
Soma (perikaryan)
What is a multipolar neuron?
One that has a single axon and multiple dendrites
What is a unipolar neuron?
One that only has one protoplasmic process extending from the cell body.
What is a bipolar neuron?
One that has two extensions from the cell body - typically one axon and one dendrite.
How many neurons is the human brain estimated to have?
100 billion neurons
How many synapses is the human brain estimated to have?
100 trillion synapses
The adult brain will tend to lose how many neurons every day?
10,000-20,000 per day
What do neurons need electricity for?
To transmit signals
What are nerve signals not good for? What does it do instead?
Transmitting information long distances. Taking lots of signals and integrating them together.
What happens if multiple pulses/signals reach a terminal in quick session?
They will be summated into a larger signal/action potential (temporal integration)
If multiple cells signal to the same cell in quick session, what occurs?
They will be summated into a larger signal/action potential (spatial integration)
The speed of change in Na+ permeability is what?
Fast
The speed of change in K+ permeability is what?
Slow
What is the typical resting potential of an axon?
-70mv
Briefly describe the stages that occur in an action potential.
Resting potential, depolarisation, repolarisation, hyperpolarisation, resting potential.
Influxes of sodium into the axon causes what?
An increased positive charge, meaning points in the axon slightly further down the cell will be more (in relative terms) negatively charged. This then causes a cascade of changes in charge, in and out of the axon, resulting in an increased positive charge inside the axon. This leads to K+ ions diffusing out of the cell. Continuous process that leads to a propagation of the action potential along the axon.