Lecture 16 - Learning & Memory

Question 1

Why are learning and memory important?

Answer 1

To be able to adapt to changes in the environment

Question 2

Learning

Answer 2

Acquire and process information from the environment.

- Changes the nervous system

Question 3

Memory

Answer 3

Ability to retain this information.

Question 4

Hypothesized Memory Processes

Answer 4

3 breakdowns:

1. Encoding
   ex: forgetting a name after hearing it
   or
   ex: someone distracting you during lect & you miss what is said (not in STM)
2. Consolidation
   ex: asked to hear name & is in STM, but didn’t study it/rehearse it
3. Retrieval
   ex: payed attention in STS & studied in LTM, but at test got retrieval problem
   - tip of tongue
   - can’t get it when you need it

Question 5

Multiple Trace Hypothesis of Memory

Answer 5

• memory is always changing
• dependent on your interpretation of the events

LTM - b/c of rehearsal, b/c of studying, it can store a lot of mem for a long time

ITM & STM - smaller capacity - last longer

Sensory buffer - dies a way v. quickly unless you pay attention to that info

Question 6

Multiple Memory Systems Hypothesis

Answer 6

Memory can be divided into categories that reflect the type of information being remembered.

Each system primarily employs a distinct brain region.

Declarative –> Hippocampus
Procedural –> Basal Ganglia
Emotional –> Amygdala
‘Working With’ Memory –> Prefrontal Cortex

Question 7

Sensory memory

Answer 7

Large capacity, but rapid decay.

Sensory association areas involved.

Example: Your mother is lecturing you and you aren’t paying attention, however, if asked, you can repeat the last sentence she said. (b/c still on sensory buffer)

Question 8

Short-term memory(Working memory)

Answer 8

Lasts for seconds to minutes. (encoded)

Severely limited capacity.
magical 7 ± 2 – digits, letters, etc. (ex: phone #)

Available to conscious awareness. - aware that you have this in STM & you can use it

Prefrontal cortex involved.

Example: remember a phone number. between looking it up and dialing.

Question 9

Intermediate-term Memory

Answer 9

Lasts for hours and days.

May be transferred to LTM through rehearsal.

Example: remembering where you parked your car.

Question 10

STM and Forgetting

Decay theory

Answer 10

memory fades away with time, unless there is rehearsal.

Question 11

STM and Forgetting

Interference theory

Answer 11

memory for other material interferes with information we are trying to remember.

ex: studying 3 diff courses & piles on
- new stuff can interfere with what you’re trying to rmbr

Question 12

Decay Theory of Forgetting

Answer 12

memory fades away with time.
unless there is rehearsal.

Example: reviewing notes after class.

Question 13

Interference Theory of Forgetting

Answer 13

Better recall when presentation of information is spaced.

Example: studying versus cramming.

Question 14

Interference Theory of Forgetting

Answer 14

Better recall for items presented first (primacy) and last (recency) in a list.

Question 15

Mechanisms of Primacy and Recency

Primacy:

Answer 15

Memory system has enough resources to transfer items at the beginning of a list into LTM.

Question 16

Mechanisms of Primacy and Recency

Recency:

Answer 16

Items at the end of the list are still in STM and are therefore available for recall.

Question 17

Factors Affecting Primacy and Recency

Answer 17

A distractor task at the end of a list interfered with recency, but not primacy.
- Interrupts rehearsal.

A faster presentation rate interfered with primacy, but not recency.
- Increases load and effects transfer of information from STM to LTM.

Changing the length of delay between training and testing interfered with both primacy and recency.

Question 18

Consolidation

Answer 18

Hippocampus and amygdala involved.

Memories are subject to modification during reactivation and reconsolidation.

Memories are more likely to reflect how person perceived the event, rather than what actually happened.

• Confidence is not correlated with accuracy.
• Implications for eyewitness accounts, repressed memories of abuse.

Question 19

Learning and memory involves multiple

Answer 19

processes, traces and systems.

Question 20

Processes

Answer 20

Encoding, consolidation and retrieval.

Question 21

Traces

Answer 21

Sensory, short-, intermediate- and long-term.

Question 22

Systems

Answer 22

Declarative, procedural, emotional, ‘working-with’.

Question 23

Long-term memory

Answer 23

Declarative

• Episodic
• Semantic

Non-declarative

• Procedural
• Perceptual
• Conditioning
• Non-associative

Lasts for months and years.

Takes a long time to consolidate.

Question 24

Declarative memory

Answer 24

Knowledge we have conscious access to.

Often referred to as EXPLICIT MEMORY.

Question 25

Declarative memory

Episodic

Answer 25

Personal experiences / events etc.
- Canoeing on Lake Winnipeg, surfing in San Diego.
Often referred to as AUTOBIOGRAPHICAL MEMORY.

Question 26

Declarative memory

Semantic

Answer 26

Conceptual knowledge

• “Where is Lake Winnipeg, where is San Diego?”
• “How do you canoe, how do you surf?”

Question 27

Classical Conditioning

Answer 27

association between STIMULUS-STIMULUS.

hippocampus is involved.

Unconditioned stimulus (US)
stimulus (puff of air) that produces UR.

Unconditional response (UR) 
reflex (eye blink) to US.

Conditional stimulus (CS) 
an arbitrary stimulus (tone) paired closely in time with an US.

Conditioned response (CR) 
behaviour (blinking) now occurs in response to CS (without need for US).

Question 28

Classical Conditioning

How general is this effect?

Answer 28

dog salivates to sounds similar to og stimulus –> generalization but doesn’t persist b/c learns to discriminate b/c gets food only during og

• if she hears bell without receiving food she’ll stop salivating to the bell
• after some time passing, when she hears again she’ll salivate – spontaneous recovery

Question 29

Mechanism for Classical Conditioning: Hebbian learning

Answer 29

If a synaptic connection is repeatedly active at the same time a post-synaptic neuron fires, then this will lead to changes in the structure or chemistry that strengthen the connection.

Question 30

Non-declarative Memory

Answer 30

Performance informed by IMPLICIT knowledge.

Perceptual memory
- Priming

Procedural memory
- Operant / instrumental conditioning

Emotional memory
- Conditioned fear response

Non-associative memory
- Habituation / sensitization

Question 31

Perceptual Memory: Priming

Answer 31

An alteration of response to a stimulus as a result of prior exposure.

Can last for hours.

Not dependent on level of processing.

Reduced (but not eliminated) when presentation and test modalities are different.

Perceptual short-term memory involves the sensory association cortices.

Question 32

Procedural Memory: Instrumental / Operant Conditioning

Answer 32

Pressing a button provides a reward.
- Increases the likelihood that the animal will press the button again.

Association between STIMULUS-RESPONSE.

• Stimuli following a behaviour can be either:
• • Reinforcing: perceived as positive.
• • Punishing: perceived as negative.
• Basal ganglia are involved.

Question 33

Procedural Memory: Motor Learning

Answer 33

Series of connected movements that become automatic with practice.

Other examples: how to tie a shoe lace, ride a bike, drive a manual transmission, play piano.

Question 34

Emotional Memory: Conditioned Fear

Answer 34

• Association between stimulus-valence (pleasant-unpleasant).
• Amygdala is involved.

Little Albert

• Conditioned to fear rats – hammer hitting metal.
• Extended to other furry animals and objects.

Nothing lasts forever!
- If CS is repeated without US often enough, then the CR disappears (EXTINCTION).

Question 35

Non-associative Memory: Habituation

Answer 35

• Ignore incoming information that is not relevant.
• Most basic form of learning.
• • Even worms can do it.
• • Tap response (C. elegans)

Question 36

Memory can be subdivided into multiple categories

involve distinct brain regions.

Answer 36

Short-term memory
Prefrontal cortex, sensory association areas

Declarative long-term memory
Hippocampus

Procedural long-term memory
Basal ganglia, motor association areas, cerebellum

Emotional long-term memory
Amygdala

Question 37

Long-term potentiation

Answer 37

A long-term increase in the excitability of a neuron to a particular synaptic input caused by repeated high-frequency activity of that input.

• EPSP’s are summated as successive EPSP’s occur and before past EPSP’s have dissipated.

Question 38

Synaptic plasticity

Answer 38

LTP strengthens existing synapses and creates new ones.

Important for recovery of function post stroke.

Question 39

Take Home Message

Answer 39

Memory is multifaceted.

- Many processes, traces, systems and brain regions involved.

Question 40

In classical conditioning, an organism
A) learns the consequences of a specific behavior.
B) identifies and categorizes objects.
C) shows a species-typical behavior in response to a previously unimportant stimulus.
D) is able to recognize objects by the sounds they make.
E) forms an association between a response and a stimulus.

Answer 40

C) shows a species-typical behavior in response to a previously unimportant stimulus.

Question 41

You are listening to a song on the radio while doing your homework. The phone rings. Your mother has called to tell you that your favorite uncle has died after being hit by a car. Three months later, you again hear the same song and suddenly feel very sad. In this example, the unconditional response is
A) the voice of your mother as she relays the bad news.
B) listening to the song.
C) your feeling about the song prior to the phone call.
D) your feeling about your uncle before he died.
E) feeling sad when your mother calls with the bad news.

Answer 41

E) feeling sad when your mother calls with the bad news. (UR)

Question 42

The \_\_\_\_\_\_\_\_ states that a weak synapse will be strengthened if its activation occurs at the same time that the postsynaptic neuron fires.
A) perforant path hypothesis
B) law of effect
C) all-or-none principle
D) Hebb rule
E) law of summation

Answer 42

D) Hebb rule

Question 43

The ability to recall a series of events is referred to as
A) serial memory.
B) spatial learning.
C) perceptual learning.
D) episodic learning.
E) observational learning.

Answer 43

D) episodic learning.

Question 44

Intense electrical stimulation of axons within the hippocampal formation results in
A) long-term potentiation of postsynaptic neurons.
B) axoaxonic inhibition of presynaptic neurons.
C) recurrent inhibition of the stimulated axons.
D) long-term potentiation of presynaptic neurons.
E) B and C are correct.

Answer 44

A) long-term potentiation of postsynaptic neurons.