1 - Memory and Learning

Question 1

Two Major Categories of Memory?

How is it sorted?

Answer 1

Declarative / Non-Declarative

Sorted by:

1. Type of information learned
2. Anatomical systems required

Question 2

Declarative Memory

Brain structure?

Type of information?

Answer 2

Brain: Medial Temporal lobe; diencephalon, limbic system structures

Information: Facts, Events–can be brough to conscious awareness or explicity declared

“Knowing that”

Question 3

Non-declarative Memory

Brain areas?

Type of Information?

Answer 3

Brain: Striatum, Cerebellum, Amygdala* (each for different type)

Type of Information: Procedural skills/habits, skeletal musculature (Pavlov dog), Emotional response (fear from memory, etc)

**Requires motor-related system: basal ganglia, cerebellum

“Knowing How”

Question 4

Clinical: Dissociation of declarative and non-declarative memory systems?

Answer 4

Depend on anatomically distinct systems

Loss of one system does not impair function of the other; those with severely impaired declarative memory can still learn new skills

“You could display new learned skills with no conscious awareness of ever having practiced”

Question 5

Temporal Stages of Declarative Memory:

Consolidation

Answer 5

First Stage of (big picture) Processing*

Stable (long-term) memories are first processed through immediate and short-term forms

There are earlier steps to memory, (immediate, short term, etc)

Question 6

Temporal Stages of Declarative Memory:

Immediate Memory

Answer 6

Very Brief, Very Large (theoretical) Capacity

Sensory Register, sum of all ongoing sensory input to cerebral cortex

Volatile - Rapidly lost if not processed further

Question 7

Temporal Stages of Declarative Memory:

Short Term

Answer 7

Short duration (seconds/minutes)

Extremely small capacity (7+/-2 pieces); information at center of attention

Question 8

Temporal Stages of Declarative Memory:

Long Term Memory

Answer 8

Very long duration (years / decades)

Very Large Capacity

Vast size, very resistant to forgetting

Formed through consolidation; repetition enhances, partially consolidated is vulnerable–head trauma, seizures, etc

Question 9

What is critical for consolidation of memories to long term?

Answer 9

Sleep, brian reactivates at night to reinforce thi stage

Question 10

Clinical: How to test short and long term memory?

Answer 10

Short: Digit +/- test (5-9)

Long: Recall of autobiographical information, famous faces test*

*Susceptible to confabulations; or unintentional wrong answers

Question 11

Retrograde vs Anterograde Amnesia

Answer 11

Retro - Loss of memories which were already formed; damage to long-term memory areas

Antero - Inability to reform new memories; damage to consolidation areas

Question 12

Retrograde Amnesia

Temporally Limited Retrograde Amnesia

Answer 12

Loss of old memories, damage to long-term memories

Temporally Limited - Short span (you forgetting getting hit by the car, but remember stuff before and after)

Question 13

Anterograde Amnesia

Answer 13

Usually accompanied by temporally limited retrograde amnesia

Question 14

What areas of the CNS do procedural memory rely on?

What areas of the CNS do declarative memory rely on

Answer 14

Neural systems that modulate motor function

- - -

Neural systems connected to association, high level of sensory cortical areas, and limbic cortex

Question 15

Association Cortex

Answer 15

Declarative memory depends on neural systems connected to heteromodal association and high level sensory unimodal association (ex. fusiform gyrus) cortical areas

Question 16

Dorsolateral Prefrontal Cortex (part of association cortex)

Answer 16

“Executive” or “Working Memory” function

Exec - direct attention, entry of information into short-term memory, use information

Working - storage in short term memory

Question 17

System Summary:

Immediate Memory

Short Term

Consolidation

Long-Term Memory

Answer 17

Immediate Memory - High level sensory cortical; association

Short Term - High level sensory; association; dorsolateral prefrontal

Consolidation - Medial temporal lobe; related limbic structures

Long-Term Memory - High level sensory cortical; association

Question 18

How are long term memories stored?

Answer 18

Distributed Manner

Single memory is complex collection of many different stimuli; e.g. visual aspects stored in higher order areas different than smell or taste

Question 19

Long Term Memory strengthing?

What does this say about the requirements for consolidations of memory?

Answer 19

Strengthened by increasing synaptic connections between neurons in multiple cortical areas

Consolidation of memory requires interconnected limbic structures

Question 20

How are subdivisions of the hippocampus connected?

Clinical: Damage to these connections?

Answer 20

In a loop

Clinical: Anterograde Amnesia

Question 21

Clinical: Lesions locations (2) which can impair consolidation?

Answer 21

Medial Temporal Lobes

Medial Diencephalic Structures

Breaking of declarative memory system loops

Question 22

Long Term Potentiation (LTP)

Long Term Depression (LTD)

Where do these occur?

Answer 22

Process for strengthing synapses in memory storage

Process of weakening synapes in memory storage

Declarative: Hippocampus, Neocortex

Procedural: Cerebellum, Basal Ganglia

Question 23

Long Term Potentiation (LTP)

Neurotransmitter

Locations

Answer 23

NT: Glutamate

Locations: Spines of Pyramidal Neurons at glutamate synapses in Hippocampus and Neocortex

Question 24

What type of receptors are on post synaptic membranes in LTP?

Answer 24

non-NMDA (AMPA, kaitnate)

NMDA glutamate

Question 25

What do NMDA receptors require for gating?

What does this lead to?

Answer 25

Depolarization + Glutamate

Increased calcium, increased protein activation, increased NMDA receptors, increased synapses