Chapter 4: Learning and memory

Question 1

What is neural plasticity and what may it involve?

Answer 1

The ability of the brain’s neural structure or function to be changed by experience throughout the lifespan, which provides the physiological basis of learning and memory.
-May involve a single neuron, a pair of neighbouring neurons or entire networks of neurons.

Question 2

What is synaptic plasticity and how may it occur?

Answer 2

The ability of the synapse to change over time, which may occur through the growth or formation of new synaptic connections that strengthen the synapse, or through disuse of synaptic connections that weaken or eliminate the synapse.

Question 3

What is Hebb’s cell assembly (neural pathway)?

Answer 3

Learning results in interconnected groups of neurons that form networks or pathways.

Question 4

What happens when a synaptic connection is strengthened?

Answer 4

It makes presynaptic and postsynaptic neurons more likely to fire and to transmit their signals more forcibly and efficiently in the future.

Question 5

What does learning involve according to Hebb?

Answer 5

The establishment and strengthening of neural connections at the synapse.
Eg. When we are learning a new task such as playing the piano, where regular practice will strengthen neural connections enabling you to get better at it and make fewer mistakes.

Question 6

What is Hebb’s rule?

Answer 6

‘Neurons that fire together, wire together’

Question 7

What is long-term potentiation (LTP)?

Answer 7

The long-lasting strengthening of synaptic connections resulting in enhanced or more effective synaptic transmission.

Question 8

What is the effect of long-term potentiation on neurons and what happens the more connections are activated?

Answer 8

Improves presynaptic and postsynaptic neuron communication at the synapse, which enables presynaptic neurons to be more easily activated.
-The more the connection is activated, the more the connection is strengthened, thus also strengthening the specific pathway

Question 9

What is long-term depression (LTD) and what does it result from?

Answer 9

The long-lasting decrease in the strength of synaptic transmission, which results from a lack of stimulation of pre- and postsynaptic neurons or from prolonged low-level stimulation.

Question 10

What is the effect of long-term depression on neurons?

Answer 10

Postsynaptic neurons become less responsive to the neurotransmitters released by presynaptic neurons.
-This weakens the synaptic connection, which also weakens or even silences communication at the synapse.

Question 11

Why is it believed that LTD may be just as important as LTP for learning and memory?

Answer 11

The weakening or elimination of unused synapses through LTD may prune unimportant or unwanted connections, leaving only the important connections that have been strengthened through repeated use by LTP.
-‘Use it or lose it’

Question 12

List 3 similarities between LTP and LTD:

Answer 12

• Both involved glutamate
• Both are long-lasting effects
• Both are activity depend (Eg. More or less active)

Question 13

Describe the role of neurotransmitters in relation to learning and memory:

Answer 13

Generally, they enable the communication of the info being learned, and initiate or contribute to important structural changes at the synapse that help ensure the memory is durable and long-lasting when formed.

Question 14

What are neurohormones?

Answer 14

Are chemical messengers that are manufactured by neurons and released from axon terminals into capillaries (tiny blood vessels) where they are absorbed into the bloodstream and carried to target neurons or other cells.

Question 15

What is glutamate (Glu)?

Answer 15

The main excitatory neurotransmitter throughout the brain and enhances info transmission by making postsynaptic neurons more likely to fire.

Question 16

How does glutamate play a crucial role in learning and memory?

Answer 16

It promotes the growth and strengthening of synaptic connections between neurons within a neural pathway, which represents the memory that has been learned.

Question 17

What is consolidation?

Answer 17

The biological process of making newly formed memory stable and enduring after learning.

Question 18

Describe the process of consolidation and how long is consolidation vulnerable to disruption:

Answer 18

• New incoming info is temporarily stored in short-term memory before it is transferred to long-term memory.
• If consolidation is disrupted, new info may not be transferred from short-term to long-term memory or it may not be stored well in long-term memory if it arrives there.
• Consolidation is vulnerable to disruption for at least 30 mins after learning

Question 19

Describe the 2 phases of consolidation:

Answer 19

An initial rapid process for temporary storage, followed by a slower, more permanent process for long-term storage that could take days, weeks, months or even years.

Question 20

What is the role of adrenaline in consolidation?

Answer 20

Adrenaline can enhance the consolidation of long-term memories of emotionally arousing experiences, which means that these memories are more likely to be well remembered.

Question 21

How do stress-inducing events affect memory? Give an example:

Answer 21

Emotionally arousing experiences, which are usually unpleasant, leave memories that are lasting, vivid and highly detailed from a personal perspective.
Eg. A victim of a crime will remember what happened much better than the experiences of their everyday routine.

Question 22

Describe the process of how adrenaline effects consolidation:

Answer 22

• When released during heightened emotional arousal, adrenaline induces the release of noradrenaline in the amygdala, which is located deep with the brain and has a crucial role in processing emotions
• It is believed that the presence of noradrenaline during consolidation may activate the amygdala to signal the nearby hippocampus, that details of the relevant experience are significant and its long-term storage should be strengthened

Question 23

How does the level of adrenaline effect consolidation?

Answer 23

Moderate doses of adrenaline seem to enhance consolidation, while higher or lower levels are less effective.

Question 24

How does the emotional significance of events affect the strength of the memories of events? Give an example:

Answer 24

The more emotionally significant the event to an individual, the longer-lasting its memory is likely to be and more detail that will be recalled.
Eg. Participants given a drug that promotes the release of adrenaline when viewing emotionally arousing images will tend to have enhanced memory of those images.

Question 25

What is synaptogenesis?

Answer 25

The formation of a synapse between two neurons