Folio 1 Mechanisms of Learning

Question 1

What are neurons?

Answer 1

A neuron is a nerve cell that is specialised to receive, process and/or transmit information to other cells within the body

Question 2

What is the role of dendrites in neural transmission?

Answer 2

Dendrites are thin extensions of a neuron that receive information from other neurons and transmit it to the soma.

Question 3

What is neural transmission?

Answer 3

Neural transmission occurs when a neuron is activated, or fired (sends out an electrical impulse)

Question 4

What is the role of the soma (cell body) in neural transmission?

Answer 4

The soma integrates the neural information received from dendrites and sends it to the axon.

Question 5

What is the role of the axon in neural transmission?

Answer 5

The axon is a single, tube-like extension that carries neural information away from the soma towards other neurons by stimulating the release of neurotransmitters from the terminal buttons. The terminal buttons can be located at the end of the axon collaterals (which the axon splits into)

Question 6

What does a terminal button do ?

Answer 6

The terminal button is a small structure like a sac that stores and secretes neurotransmitter manufactured by the neuron

Question 7

What is a neurotransmitter?

Answer 7

A neurotransmitter is a chemical substance produced by a neuron that carries a message to other neurons or cells in muscles and organs. They are produced by presynaptic terminal buttons when stimulated by a neural impulse.

Question 8

What is a neural impulse?

Answer 8

A neural impulse is information that travels along the axon as an electrical impulse

Question 9

How do neurotransmitters work?

Answer 9

A neurotransmitter works by attaching itself (‘binding’) to receptor sites of postsynaptic neurons that are specialised to receive that specific neurotransmitter

Question 10

What is the role of the synapse in neural transmission?

Answer 10

The synapse contains a small gap separating neurons. The synapse consists of: a presynaptic ending that contains neurotransmitters, a postsynaptic ending that contains receptor sites, and a synaptic gap in between.

Question 11

What is the definition of plasticity?

Answer 11

Plasticity is the ability of the brain’s neural structure or function to be changed by experience throughout the lifespan

Question 12

What is developmental plasticity?

Answer 12

Developmental plasticity refers to changes in the brain’s neural structure in response to experience during its growth and development. It involves synaptogenesis and synaptic pruning.

Question 13

What is synaptogenesis?

Answer 13

Synaptogenesis is the process of forming new synapses. This is seen in its greatest effect in infants and children, where we see their brains form far more synaptic connections than they will ever use. Synaptogenesis occurs rapidly within the first year of life, this is believed to allow the brain to have the capability to respond to the constant stream of new environmental input.

Question 14

What is synaptic pruning?

Answer 14

Synaptic pruning is the process of eliminating synaptic connections. Experience determines which connections are retained, and which ones are pruned. Pruning follows the rule ‘use it or lose it’. Synaptic pruning is done to enhance the brains efficiency by breaking off unneeded connections.

Question 15

Why is the hippocampus important in learning?

Answer 15

The hippocampus has a crucial role in forming new declarative explicit memories (semantic and episodic). Because of this role the hippocampus plays a large part in learning, as we need to have a memory of the experiences in order to learn from them and see an influence/change in our behaviour

Question 16

Why does synaptic pruning occur?

Answer 16

It’s necessary because the brain doesn’t know when it’s building itself, which cell-to-cell connections are going to be the most important connections, so as we get older and gain more experiences, we begin to establish which ones are important and used the most. Those that are not used are simply removed because they are inefficient and not needed.

Question 17

What is adaptive plasticity?

Answer 17

Adaptive plasticity refers to changes occurring in the brain’s neural structure to enable adjustment to experience, to compensate for lost function and/or to maximise remaining functions in the event of brain damage. Most evident in neural processes that occur when the brain has experienced damage. AP is particularly quicker, more substantial and more extensive in infancy and childhood. Involves rerouting and sprouting

Question 18

What is rerouting?

Answer 18

In rerouting, an undamaged neuron that has lost a connection with an active neuron may seek a new active neuron and connect with it instead.

Question 19

What is sprouting?

Answer 19

Sprouting is the growth of new bushier fibres with more branches to make new connections. Thus, sprouting not only involves nerve growth, but rerouting as well.

Question 20

What does adaptive plasticity; rerouting and sprouting do ?

Answer 20

Sprouting and rerouting enable the formation of entirely new neural connections at the synapse to compensate for loss of function due to brain damage. The brains Adaptive plasticity enables it to take over or shift functions from damaged to undamaged areas.

Question 21

How do we make adaptive plasticity work?

Answer 21

In order for neurons to reconnect or form new connections, they need to be stimulates through activity. Relevant types of experience during recovery from brain damage are therefore important influences on the speed of recovery.

Question 22

How do Developmental and Adaptive plasticity interact?

Answer 22

• possibly through the fact that a child can have both developmental and adaptive plasticity working in their brain, where as an adult may only have adaptive plasticity.