Lecture elevem: Learning and Memory

Question 1

What is Perceptual learning ?

Answer 1

(better and faster identification of faces/objects if seen before)

Question 2

Stimulus-Response learning

Answer 2

Classical conditioning (initial neutral stimulus induces reflexive behavior)

Instrumental conditioning (relation between stimulus and behavior for reward/punishment)

Question 3

Motor learning

Answer 3

(ride a bike, tennis, etc)

Question 4

Relational learning (declarative, explicit memory

Answer 4

1. Relations in time (episodic: on my 18th birthday I got a car)
2. Relations with concept (semantic: object with 4 wheels is a car)
3. Relations in space (spatial: navigation)

Question 5

S-R learning at neural level

Answer 5

1. Food induces salivation
   (hardwired connection between neurons that detect food and neurons that induce salivation)
2. Sound Bell: no response
   (weak connection between neurons that detect the bell sound and neurons that induce salivation

after learning

3. Sound bell induces salivation
   (synapses connecting neurons that detect the sound and neurons that induce salivation have been strengthened

Question 6

Hebb Rule

Answer 6

“If a synapse is active at about the same time that the post-synaptic neuron is active, that synapse will be strengthened”.

Question 7

Long Term Potentiation (LTP)

Answer 7

Repeated stimulation of axon (causing an action potential in the post-synaptisch neuron) leads to long-lasting increase of excitatory post-synaptic potential (EPSP

Question 8

LTP is frequency specific

Answer 8

LTP requires repeated stimulation at high frequency

As a result of this, EPSPs will overlap and sum to become strong enough to depolarise the postsynaptic neuron

Question 9

LTP requires …

Answer 9

LTP requires activation of the axon and depolarisation (action potential) of the post synaptic neuron

Question 10

Associative LTP:

Answer 10

If a strong and weak synapse are activated together (and the postsynaptic neuron depolarises) the weak synapse will become stronger

Question 11

Requirements for LTP:

Answer 11

1. Axon active (secretion neurotransmitter (glutamate) in synaptic cleft)
2. Depolarisation postsynaptic neuron
   Precisely these 2 conditions have to be met for opening the N-methyl-D-aspartate (NMDA) receptor

Question 12

Axon active (secretion neurotransmitter (glutamate) in synaptic cleft)
.
Why cant the calcium channel open?

Answer 12

Magnesium Ion blocks the NMDA receptor

Glutamate can bind with the NMDA receptor, but ion channel is normally blocked by Mg2+ ion

Question 13

Depolarisation postsynaptic neuron

Answer 13

depolarisation of the postsynaptic neuron evicts the magnesium ion and unblocks the channel.
Now glutamate can open the ion channel and permit the entry of calcium ions.

Question 14

What is calcium doing after it enters the cell?

Answer 14

Ca2+ works as 2nd-messenger and activates the enzyme CaM-KII to add new AMPA receptors

Question 15

2 types of reinforcement

Answer 15

Reinforcement promotes behavior

Positive Reinforcement: reward promotes behavior
pushing lever leads to food
If you behave good you get a sweet

Negative Reinforcement: removal negative stimulus promotes behavior
pushing lever stops electrical shock
If you behave good you may get out of your room

Question 16

2 types of punishment

Answer 16

Punishment reduces behavior

Positive Punishment: negative stimulus reduces behavior
pushing lever leads to electrical shock
if you behave badly you have to go to your room

Negative Punishment: removal of positive stimulus reduces behavior
pushing lever ends food supply
If you behave badly you don’t get sweets

Question 17

Neural mechanism involved with reinforcement: “the pleasure center”

Answer 17

Around 1950, James Olds en Peter Milner studied if electrical stimulation of the brainstem reticular formation could improve spatial navigation in rats.

As a control, they first studied if the stimulation was not perceived as unpleasant

In fact, just the opposite was true!

The rats kept turning back to the place that led to stimulation: they liked it!!

Question 18

Pleasure center localized in medial forebrain bundle

Answer 18

Connects dopaminergic neurons in ventral tegmental area with neurons in nucleus accumbens

Question 19

Dorsolateral prefrontal cortex

Answer 19

Particularly strong evidence for involvement of the dlPFC in working memory a.o. from research in monkeys by Patricia Goldman-Rakic

Question 20

non-declarative memory (implicit memory.

Answer 20

memories you are not aware of

Question 21

declarative memory (explicit memory):

Answer 21

Memories you are aware of and that can be verbally expressed

Question 22

DECLARATIVE MEMORY IS LOCALIZED IN?

Answer 22

TEMPORAL LOBES

Question 23

declarative memory is:

Answer 23

relative memory

Question 24

brain regions: episodic (events experienced)

Answer 24

Relations in time

Medial temporal

Question 25

brain regions of semantic (facts)

Answer 25

Conceptual relations

Lateral temporal

Question 26

brain regions: spatial

Answer 26

Spatial relations

Para hippocampus

Question 27

retrograde amnesia is:

Answer 27

cannot remember events prior to brain damage

Question 28

anterogate amnesia is:

Answer 28

cannot remember events after brain damage

Question 29

what happened to patient HM (Henri Gustav Molaison

operated in 1953, died in 2008

Answer 29

bilateral medial temporal lobectomy to surgically resect the anterior two thirds of his hippocampi, parahippocampal cortices, entorhinal cortices, piriform cortices, and amygdalae in an attempt to cure his epilepsy.

But.. NO storage of new DECLARATIVE memory

Question 30

In patients with hippocampal damage, which kind of learning is still possible?

Answer 30

E.G.: Perceptual priming: improved recognition if seen before

Question 31

does retrograde amnesia occur to patients with hippocampal brain damage?

Answer 31

Hippocampus lesions also lead to retrograde amnesia, the severity depends on the extent of damage:

Question 32

is the activation of the hippocampus related to consolidation of memory?

Answer 32

That hippocampus damage results in limited retrograde amnesia suggests an involvement limited to the initial anchoring of the memory trace in other brain regions (memory consolidation).

Question 33

london taxi drivers have a larger… and that is because…

Answer 33

a larger (posterior) hippocampus…. because the

Question 34

Reconsolidation of memories

Answer 34

If we learn something new about a specific subject (or person) we need to change/extend our memories

During reconsolidation the old memory is retrieved and adjusted. In this period, the memory is vulnerable!!

Question 35

what can we use Electroconvulsive Shock (ECS) for?

Answer 35

ECS used to treat depression

Electrical current through the head excites many neurons in the brain and produces an epileptic seizure

Question 36

is there a side effect of electroconvulsie shock? :D

Answer 36

Side effect: retrograde amnesia for events around the time of stimulation
(the seizure erases short-term memory active at that moment and consequently prevents consolidation of these memories into long-term memory)

If long-term memories are retrieved during reconsolidation, can we then erase these e.g. with ECS!!!???