Learning & Memory

Question 1

Learning

Answer 1

process of acquiring new information.

Question 2

Memory

Answer 2

the outcome of learning

Question 3

The Case of H.M.

Answer 3

• Had Epilepsy from childhood
• 1950s: He was a young adult, couldn’t work.

• Surgical treatment:
remove bilateral medial temporal lobes (seizure foci).

• After surgery, HM could no longer form new long-­term memories (anterograde amnesia)
– Could remember things from before surgery
– Could remember things for a few min (short‐term memory)
– Could learn new procedural/implicit memories
– Intact intelligence/personality

Question 4

H.M.

Lessons

Answer 4

• Hippocampus/MTL critical for forming new explicit memories
• Different types of memory
supported by different structures

HM Revolutionized our
understanding of memory!

Question 5

Memory

Types/Stages

Answer 5

• Time scale of storage:
– Sensory memory
– Short term memory (STM),
working memory
– Long term memory (LTM)

• Types of memory (knowledge)
– Declarative/explicit
– Procedural/implicit

• Stages of memory
– Encoding
– Storage
– Retrieval

Question 6

Time scale of storage

Answer 6

– Sensory memory
– Short term memory (STM),
working memory
– Long term memory (LTM)

Question 7

Time Scale:

Sensory Memory

Answer 7

• Available for brief periods, overridden
– Visual: iconic (<200 ms)
– Auditory: echoic
(several seconds)

• High capacity

Question 8

Sensory Memory:

Iconic Memory

Answer 8

Full/partial report technique.

• Sperling’s partial report
-­‐ flashed very briefly
-­‐ tones used to indicate line to report
-­‐ performance much better than
expected from full report
-­‐ evidence for brief, high-capacity iconic
memory

Question 9

Short‐term Memory
vs
Long­‐term Memory

Answer 9

• H.M. had intact short-­term memory (STM) but impaired long-term memory (LTM)
• What’s the relationship/difference
between STM & LTM?

– Hypothesis I:
Info first in STM then transferred to
LTM

– Hypothesis II:
STM and LTM are the “same”
memory system; LTM simply places
greater demands on the memory
system.

– Hypothesis III:
STM and LTM are relatively
independent learning and memory systems

Question 10

Patient KF

Answer 10

– 28 years old

– LH damage to cortical areas:
parieto-­‐occipital
(motorbike accident age 17)

– Normal IQ

– Poor STM:
Digit span = 1-­‐2 (controls 5-8)

– Normal LTM

Question 11

HM and KF

Answer 11

Both had a double dissociation of STM/LTM

• What’s the relationship/difference between STM & LTM?
– LTM is not just a harder version of STM

Question 12

Working Memory

Answer 12

active maintenance of information

– Limited capacity
– Short-­‐term
– Information that can be acted on and processed
(e.g., backward digit span test)
– Maintenance and Manipulation

Question 13

Types of Memory

knowledge

Answer 13

– Declarative/explicit

– Procedural/implicit

Question 14

Stages of Memory

Answer 14

– Encoding
– Storage
– Retrieval

Question 15

Baddeley-­‐Hitch’s Working

Memory Model

Answer 15

– Central executive controls
2 subordinate systems:
• Phonological loop (acoustical)
• Visuospatial sketchpad (visual)

Are there multiple WM systems?
Are they independent?

Question 16

Can you store both visual and auditory info simultaneously?

Answer 16

yes, independent systems

Question 17

Evidence for multiple WM systems:

PET study

Answer 17

Verbal & spatial memory tasks

activate different brain networks.

Question 18

Long-­‐term Memory

Answer 18

• Declarative memory:
knowledge with conscious access (a question you can answer explicitly)
– Episodic memory:
events we recall about own lives
(“where did you live when you were 5 years old?”)
– Semantic memory: facts/world knowledge
(“who is the president?”)

• Non-­‐declarative memory:
knowledge with no conscious access (implicit)
– Procedural memory:
motor/cognitive skills
– Perceptual priming
– Conditioned learning

Question 19

Declarative Memory

Answer 19

knowledge with conscious access (a question you can answer explicitly)

– Episodic memory:
events we recall about own lives
(“where did you live when you were 5 years old?”)
– Semantic memory: facts/world knowledge
(“who is the president?”)

Question 20

Non-­‐declarative memory

Answer 20

knowledge with no conscious access (implicit)

– Procedural memory:
motor/cognitive skills
– Perceptual priming
– Conditioned learning

Question 21

Revisiting H.M.
Procedural
vs.
Declarative Memory

Answer 21

Mirror-­‐drawing = procedural
– HM demonstrated clear learning/memory
– But no recollection of having seen task before

Question 22

Non-­‐declaratve Memory:

Procedural

Answer 22

Implicit learning without explicit awareness

• ­‐ Performance improves for repeated sequences
• ­‐ Most subjects don’t report noticing repetitions

Procedural memory / motor skill learning:
involves Basal Ganglia

Question 23

Non-­‐declarative Memory:

Priming

Answer 23

Priming:
The change in the response to a stimulus or in the ability to identify a stimulus as the result of prior exposure to that stimulus.

-­‐ Explicit test:
which of these words did you see before:
animal or house?
(H.M. would fail)

-­‐ Implicit test:
word fragment completion»
What word is this: A_I_A_?
(H.M. would show perceptual priming for previously seen words, like ANIMAL)

This is behavioral priming; can also see neural priming (smaller neural responses to a repeated stimulus).

Question 24

Priming

Answer 24

The change in the response to a stimulus or in the ability to identify a stimulus as the result of prior exposure to that stimulus.

Question 25

Classical Conditioning

Answer 25

Conditioned stimulus (CS) is paired with the unconditioned stimulus (US) to eventually give a response on its own

Question 26

Stages of Memory

Answer 26

• Encoding: Processing of incoming information to be stored
– Acquisition (registering sensory inputs)
– Consolidation
(creating a stronger stored representation)

• Storage: Permanent record of the information

• Retrieval:
Utilizing stored information to recall conscious memory or execute learned behavior.

Question 27

Encoding

Answer 27

Processing of incoming information to be stored.

– Acquisition (registering sensory inputs)
– Consolidation (creating a stronger stored representation)

Question 28

Memory

Capacity

Answer 28

• What is typical memory capacity?
– “magic number 7”?
– ~4 “chunks”?

• Individual differences
(high­‐capacity vs low-‐capacity)

• Eidetic/photographic memory
hmp://www.youtube.com/watch?v=A4ugfCjqlZ4

• Strategies for improving memory capacity
– Chunking
– Mnemonics
– Memory mapping:
hmp://artofmanliness.com/2011/09/30/how-­‐to-­‐
memorize-­‐anything-­‐you-­‐want-­‐a-­‐quick-­‐primer-­‐on-­‐mental-­‐
mapping/
– hmp://www.youtube.com/watch?v=V8S8V9VEFyI

Question 29

Strategies for improving memory capacity

Answer 29

– Chunking
– Mnemonics
– Memory mapping

Question 30

False Memories

Answer 30

• Parallels between attention & memory:
– What we perceive is not necessarily what we see;
– What we remember is not necessarily what we saw

• Problem for eye-witness testimony

Question 31

Why Do We Form False Memories?

Answer 31

• Failure in encoding:
– Insufficient memory separation

• Failure in retrieval:
– Low criteria for accepting a memory as veridical (truthful).

• “Forgotten” memories:
also failures of storage
– Decay or interference of representations

Question 32

False Memories

Answer 32

fMRI studies show that the Hippocampus responds to false memories as if the where true

Question 33

Remembering
and
Forgetting

Answer 33

“Remembering is not simply a process of passively activating stored information. Instead, people’s
expectations, metamemorial beliefs, even how they are instructed to examine their memory, influence the
kind and amount of information that is remembered.”

Dodson & Schacter, 2001

Question 34

Memory

Disorders

Answer 34

• Amnesia
• Korsakoff’s
• Alzheimer’s

Question 35

Amnesia

Answer 35

Amnesia = deficit in memory as a function of brain damage, disease, or psychological trauma

• Retrograde amnesia:
loss of previous knowledge from before event

• Anterograde amnesia:
inability to form new memories after event

Caused by damage to Bilateral Medial Temporal
lobe (MTL)

Question 36

Which type of amnesia did H.M. have?

Answer 36

?

Question 37

Retrograde

amnesia

Answer 37

loss of previous knowledge from before event

Question 38

Korsakoff’s

Answer 38

• Amnesia associated with alcoholism
• Long term alcohol abuse&raquo_space;> vitamin B deficiency
»> brain damage
• Degeneration of thalamus & mammillary bodies
• Anterograde & retrograde amnesia

Question 39

Alzheimer’s

Answer 39

• Degenerative brain disorder

• Formation of plaques & tangles
– Tau concentrated in medial temporal lobe

• Progressive dementia
– Short-­‐term memory loss
– Repetive behaviors/conversations
– Difficulty remembering names
– Difficulty performing familiar tasks
– Misplacing items / putting items in inappropriate places
– Difficulty remembering words
– Disorientation, paranoia
– Inability recognizing family/friends
– Loss of basic functions, death

• Not same as “normal aging”
• Medication can slow, but not stop progression
• Preventative “treatment”: staying mentally active

Question 40

Memory & Learning:

Where in the brain?

Answer 40

• Hippocampus/MTL
– Encoding & retrieval
– Consolida\on, ability to acquire long term memories
– NOT the ultimate storage site (which is located elsewhere in the neocortex)

• Information encoded in relevant parts of cortex

• Projected to parahippocampal regions
(perirhinal, parahippocampal, entorhinal)

• Projected to hippocampus; consolidated
• Fed back to original relevant cortical areas for storage/retrieval

Question 41

Where is information encoded?

Answer 41

“Subsequent memory paradigm”
– Present list of items while measuring brain activity
– Afterwards,
test memory
for items
– Sort neural data as a function of whether items were later remembered or forgotten
– Hippocampus & MTL more active during successful encoding

Recollection vs familiarity task
– Do you actually remember seeing this item before, or does it just feel familiar?
• Scanned during retrieval phase
• Hippocampus is active during successful retrieval
(of full episodic memory)

Question 42

Retrieval:
recollection
vs
familiarity

Answer 42

• Binding of items & contexts
– Perirhinal Cortex represents info about specific items (what, who)
– Parahippocampal represents info about context (where, when)
– Bound together in hippocampus

• Familiarity: Perirhinal is sufficient
• Full episodic memory: Need hippocampus

Question 43

Where is information stored?

Answer 43

• Re-­activation during long-­term memory retrieval
• Learned sets of sounds & pictures
• Retrieval of pictures re-­activated visual cortex (green)
• Retrieval of sounds reactivated auditory cortex (orange)
• Content of memories stored in content-­specific regions

Perceptual Activation
Memory Test

Question 44

Other
brain
areas
involved

Answer 44

• Frontal lobes
– Executive functions: Working memory
(lateral PFC, planning, goal monitoring, task switching)
– Encoding and Retrieval

• Parietal lobes
– Attentional processes, etc.