Neuro2 Epp Learning and Memory

Question 1

Define Learning and Memory

Answer 1

Learning = Process to acquire memory
Memory = Behavioral change based on experience

Question 2

What is synaptic plasticity?

Answer 2

Change in synaptic strength

Question 3

What is Hebb’s postulate?

Answer 3

If 2 neurons that fire at the same time (within a short time frame), the postsynaptic neuron undergoes metabolic changes that increase the efficiency of presynaptic neuron
This is also called Long Term Potentiation

ie. Cells that wire together fire together

Question 4

Describe Long Term Potentiation.

Answer 4

The strengthening of a synapse due to coordinated activity of 2 neurons
If downstream neuron fires within 20ms of upstream fire, LTP happens. If downstream neuron fires first, LDP occurs

Question 5

What model systems can be used to model memory?

Answer 5

Primates - highly complex memory
rodents - also complex, especially spatial memory
avians - complex memory distinction
aplysia/drosophila/zebrafish - simple systems applicable for molecular work

Question 6

Describe 3 types of memory based on time span and capacity.

Answer 6

Sensory - transient sensory input to short term (<1 sec)
Short term - Working memory, held during info processing (few mins)
Long term - possibly permanent storage of info

Question 7

What are the subtypes of long term memory?

Answer 7

Recent and remote memory

Question 8

Describe Ribot’s law and Jost’s law

Answer 8

Ribot’s law: old memories are less vulnerable to disruption than new one
Jost’s law: If 2 memories are of the same strength but different ages, older memory decays slower

Question 9

What are characteristics of a sensory memory?

Answer 9

Ability to retain sensory info after stimulus ends, while it is being transferred to short term/working memory
Requires attention but not conscious awareness

Question 10

Compare and contrast short term and working memory.

Answer 10

Often used interchangeably, but could be differentiated
short term: transient
working : transient + manipulating the info

Question 11

What is working memory?

Answer 11

Kept transiently to process/manipulate info in some way

Question 12

Describe the working memory model

Answer 12

If attentive, sensory memory goes to central executive (prefrontal cortex) -> Visuospatial and phonological regions take part to convert to LTM

Question 13

What are the subtypes of long term memory? Break it down further with examples.

Answer 13

Declarative (Explicit) and non-declarative (implicit)
Declarative -> episodic (sequence of events) and semantic (facts)
non-declarative -> procedural (how to do things), priming (repetition of info), associative (conditioned behavior), and non-associative (habits)

Question 14

What are 2 types of non-associative learning?

Answer 14

Habituation - Reduced strength of response to stimulus over multiple exposure

Sensitization - Increased strength of response to stimulus over multiple exposure

Question 15

Describe how gill withdrawal reflex in aplysia demonstrates habituation and sensitization

Answer 15

Stimulating the siphon withdraws the gills -> over repetition withdraws less -> habituation

Weak stim to siphon -> weak gill withdrawal -> strong stim to tail -> strong gill withdrawal -> weak stim to siphon -> strong gill withdrawal
This is due to strong activation of interneurons from tail that modulate activity of siphon sensory neurons

Question 16

2 types of associative learning

Answer 16

Classical and operant conditioning

Question 17

Describe classical conditioning

Answer 17

Association of neural stimulus and another stimulus that elicits a specific response, such that the neural stimulus evokes the specific response
Unconditioned stimulus and response happens naturally like food + salivation
While conditioning, unconditioned stimulus is given with an unrelated stimulus
After conditioning, unrelated stimulus becomes a conditioned stimulus (bell only) to elicit a conditioned response (salivation)

Question 18

Describe operant conditioning

Answer 18

Modification of behaviour by reinforcement after desired response
Reinforcement - anything to strengthen behavior
Punishment - anything to weaken
Positive - addition
Negative - removal

Question 19

Compare and contrast classical and operant conditioning

Answer 19

Stimulus before to elicit response vs stimulus after response to strengthen it
Learning as a result of association vs Learning as a result of consequence

Question 20

What is vicarious learning and what brain region is involved?

Answer 20

Process of learning behavior through observations, not direct experience.
Frontal cortex fires during task observation and execution

Question 21

What is procedural learning and what brain region is involved?

Answer 21

Acquisition of skill through practice
Striatum, cerebellum, basal ganglia

Question 22

What makes declarative distinct from non-declarative memory?

Answer 22

Memory you can demonstrate knowledge of by telling
Being able to convey is important

Question 23

What are the properties of episodic memory?

Answer 23

What, when, and where
3 components that are defined by:
- Sense of time
- Connection to self
- Ability to mentally place one self in that episodic moment (mental time travel)

Question 24

Which animals show episodic-like memory and how?

Answer 24

Srub jays
They bury insects over different locations but only eat unrotten ones
- what: insect
- when: rotten or not
- where: different bury locations

But still lacks the component if they still recall even outside of context and not recalling only when they are in the context

Question 25

Difference between retrograde and anterograde amnesia
What do they tell about a brain structure?

Answer 25

Retrograde = inability to recall events before lesion -> info about what the structure was doing
Anterograde = inability to form new memories -> info about what rest of brain is capable of doing

Question 26

How is the hippocampus involved in memory?

Answer 26

It encodes memories, but is not necessarily required
memory formed before HPC lesion is destroyed after lesion but memory formed after lesion remains intact
HPC lesions destroy more recent memories but not remote -> HPC doesn’t store memory indefinitely

Question 27

What is systems consolidation?

Answer 27

Long term reorganization of memory to solidify
Hippocampus recruits cortical network activation to strengthen it and thereby transfer the memory to the cortex

Question 28

What is memory reconsolidation?

Answer 28

When a memory is retrieved, it becomes vulnerable to disruption but also possible to update and integrate new information.

Question 29

What is memory extinction? Are memories unlearned?

Answer 29

Memory extinction is a decrease in memory expression due to repeated CS without US
Not unlearning but formation of inhibitory memory because there’s spontaneous recovery (ie. faster relearning if you try to recover)

Question 30

What is fear generalization?
Fear incubation?

Answer 30

Over time, fear memory is generalized to different contexts likely due to hippocampus converting the specific contextual info to a more general schematic

Fear incubation - fear memory can become stronger as they become remote

Question 31

What are the two types of memory interference?
What disease is it related to?

Answer 31

Interference is when a similar information hinders recalling an information

Retroactive - new information hinders recalling old info
Proactive - old info hinders recalling new info

Increased interference occurs in Alzheimer’s disease and aging

Question 32

How are neurogenesis and interference related?

Answer 32

Neurogenesis can promote forgetting of old info via retroactive interference but allows reversal learning

Question 33

What are 3 ways we can forget memory?

Answer 33

Encoding failure - lack of attention
Storage failure - Insufficient rehearsal and consolidation
Retrieval failure - memory inaccessible

Question 34

What are 3 ways we can forget memory?

Answer 34

Encoding failure - lack of attention
Storage failure - Insufficient rehearsal and consolidation
Retrieval failure - memory inaccessible