Learning and memory

Question 1

What is learning?

Answer 1

The process of acquiring information

Question 2

What is memory?

Answer 2

Stored, retrievable information

Not a copy but interpretation of the environment often subjective, emotionally loaded representation

Question 3

What are the memory processes?

Answer 3

Encoding
Storage
Retrieval
Reconsolidation/ Updating/Forgetting

Question 4

What is encoding?

Answer 4

Converting information into useable, “processable” and “storable” form

Question 5

What is storage?

Answer 5

Holding information (later use)

Question 6

What is retrieval?

Answer 6

Recall of stored information

Question 7

What is reconsolidation?

Answer 7

Memory traces become labile when recalled. Review/ repetition reconsolidates the trace

Question 8

What is updating?

Answer 8

New experience modifies earlier memory traces. Similar situations can result in recall but then consolidation of an altered memory trace

Question 9

What is forgetting?

Answer 9

“fading” and removal of stored information. Lack of reconsolidation?

Question 10

What is Semantic memory?

Answer 10

Facts- words and their meanings, people, faces, objects, concepts- all filled into discrete categories. Conscious

Question 11

What is Episodic memory?

Answer 11

“Snapshots” of life events. Conscious

Question 12

What is declarative memory?

Answer 12

“Knowing that”

Memory of facts and events, and refers to those memories that can be consciously recalled

Question 13

What is procedural memory?

Answer 13

“Knowing how”

Information acquired and retrieved unconsciously,including motor and cognitive skills and classical conditioning

Question 14

Where in the brain is semantic and declarative memory occur?

Answer 14

Neocortex

Question 15

Where in the brain does episodic memory occur?

Answer 15

Hippocampus

Question 16

Where is the brain does procedural memory occur?

Answer 16

Basal ganglia, cerebellum

Question 17

What is priming?

Answer 17

A earlier stimulus facilitates the recognition/identification of a second related stimulus

Question 18

What is non-associative learning paradigms?

Answer 18

Learning about a single stimulus
Habituation (decreasing response to the stimulus)
Sensitisation (increasing response to the stimulus)

Question 19

What is associative learning paradigms?

Answer 19

Classical conditioning- learning a relationship between two stimuli (cerebellum)
Fear conditioning- instantaneous association between a neutral and a fearful stimulus (depends on the amygdala)
Operant conditioning- learning a relationship between the organism’s behaviour (e.g. movement/act) and the consequences of that behaviour

Question 20

What did Pavlov do?

Answer 20

Pavolv’s dog

Conditioned dog to associated bell sound with getting food

Question 21

What is operant conditioning?

Answer 21

Skinner’s operant conditioning chamber (1930/31)

Animal’s action (e.g. pressing a lever) and consequence of that action for the animal

Question 22

What is reinforcement?

Answer 22

e.g. food reward→ action repeated with increasing probability/frequency

Question 23

What is punishment?

Answer 23

e.g. food shock→ action will be avoided

Question 24

What is self stimulation?

Answer 24

Stimulating electrode or drug application canule in the brain- model of addictive behaviour (Olds and Milner, 1954)

Question 25

What are other forms of learning?

Answer 25

Imprinting

Question 26

What is imprinting?

Answer 26

Instantaneous non-conditional form of learning: e.g. “filial imprinting” in which a young animal (hatching birds) learns the characteristics of its parents

Question 27

Examples of imprinting

Answer 27

``` Konrad Lorenz (1903- 1989) Studied instinctive behaviour and imprinting in birds Angelo d’Arrigo (2006). Bird chicks hatch under the wing of his glider, and imprinted on him. Subsequenty, he taught the fledglings to fly, hunt and to migrate ```

Question 28

What is the most common model which explains the formation of long-term (declarative) memories?

Answer 28

The multi-stage model

Question 29

What is the multi-stage memory model?

Answer 29

Information is presumed to be stored for increasing length of time at a series of “stages” in the brain: Sensory memory Short-term (working) memory Long-term memory Depending on condition, information can be “transmitted” from one stage to the next and stored for a longer period OR erased/ forgotten

Question 30

What is sensory memory?

Answer 30

Initial short-term storage of sensory information in its “elementary” form Decays rapidly if not attended

Question 31

What is iconic memory?

Answer 31

Visual sensory memory system. Capacity/level of detail high. Duration- approximately ½ second

Question 32

What is echoic memory?

Answer 32

Auditory sensory memory system. Duration- typically 2-3s; but could last up to 10 seconds

Question 33

What is short term (working) memory?

Answer 33

A low capacity system in which information is consciously held for a short period (e.g. remember a telephone number until dialing). Requires active maintenance (e.g. rehearsal of the verbal information or refreshing visual information)

Question 34

What is the capacity of STM?

Answer 34

Approx. 7 plus or minus 2 units (Miller, 1956)

Question 35

What is the capacity of STM enhanced by?

Answer 35

"chunking" (optimal: 3-element chunks)

Question 36

What is the duration of STM?

Answer 36

approx. 20-30 seconds

Question 37

How can information be transferred to long-term memory?

Answer 37

Extensive rehearsal (e.g. linking new information with existing knowledge in long-term memory)

Question 38

What are disorders of memory?

Answer 38

Retrograde amnesia Anterograde amnesia Dementia

Question 39

What is retrograde amnesia?

Answer 39

Loss of memories (But ability to learn is preserved)

Question 40

What are mild forms of retrograde amnesia?

Answer 40

Typical, ‘mild’ form- post-traumatic amnesia due to head injury (concussion) no memories of the events preceding/leading to the accident

Question 41

What are the severe forms of retrograde amnesia?

Answer 41

Infections (e.g. encephalitis), sever head injury all past/personal memories erased

Question 42

What is anterograde amnesia?

Answer 42

Loss of the ability to form new memories, to learn (BUT past memories are preserved)

Question 43

What was the case of HM?

Answer 43

Had drug-resistant temporal lobe epilepsy At the age of 27, H.M. underwent brain surgery middle part of his temporal lobe including the hippocampus was removed H.M. was “cured”: he had no epileptic seizures BUT he developed a severe anterograde amnesia Over the years he developed a very good working memory (enhanced time span by rehearsal) Could also learn new skills/motor tasks

Question 44

What is our ability to form new memories dependent on?

Answer 44

hippocampus

Question 45

What are the affects of dementia?

Answer 45

``` Affects memory (amnesia): Progressive loss of memory Progressive loss of the ability to learn But there is also: Deterioration in language, thinking and other cognitive functions ```

Question 46

What are the forms of dementia?

Answer 46

Alzheimer's (50%) Vascular (20%) Lewy body (20%) Other (10%)

Question 47

What are the brain symptoms in early AD?

Answer 47

Symptoms include progressive memory loss, decline of abstract thinking, poor judgment, confusion, mood changes, depression and/or anxiety

Question 48

What happens in the brain in early AD?

Answer 48

Signs of AD are first noticed in the entorhinal cortex and the hippocampus. Neurones in these regions degenerate and die Cholinergic neurons of the basal forebrain also start to degenerate early in the disease

Question 49

What happens in the brain in severe AD?

Answer 49

In severe AD, extreme shrinkage occurs in the brain affecting the entire cortex At this stage, patients are completely dependent on others for care

Question 50

What is the hippocampus?

Answer 50

Phylogenetically old, simple cortex in the temporal lobes | Part of the so called limbic system

Question 51

Where are the inputs and outputs of the hippocampus?

Answer 51

Neurocortex via the entorhinal cortex

Question 52

What does the hippocampus play a role in?

Answer 52

Essential role in learning memory

Question 53

What does the hippocampus iNeocortex

Answer 53

Neocortex

Question 54

What was Ramon y Cajal (1897)?

Answer 54

``` Neurons are structural and functional units of the brain Neurons communicate via synapses Neurons are “polarised” • Dendrites- input • Axon- output ```

Question 55

What is the information flow in networks?

Answer 55

The strength of synapses defines how information flows from one level to the next → Change in strength of synapses (synaptic plasticity) can serve learning

Question 56

What is the concept of Hebb's learning rule (1949)?

Answer 56

Synaptic strength is not constant and not randomly “assigned” but synapses become stronger between neurons if the two cells are simultaneously active

Question 57

What is the experimental evidence of Hebb's learning rule?

Answer 57

Long-term potentiation (LTP) (Bliss and Lomo, 1973)

Question 58

What are synapses in memory?

Answer 58

Synapses can “remember” if they receive high-frequency strong leading to activation of the postsynaptic neurons. A long-term increase in the synaptic responses (long term potentiation, LTP) develops and serves as a “memory”

Question 59

What are the properties of LTP?

Answer 59

Co-operativity | Associativity

Question 60

What do co-operativity and associativity depend on?

Answer 60

Simultaneous activation of two inputs

Question 61

What is cooperation?

Answer 61

Two weak inputs can produce LTP if activated together

Question 62

What is association?

Answer 62

A weak input can produce LTP if paired with a strong one

Question 63

What are AMPA receptors?

Answer 63

Fast, reliable transmission | Permeable for Na+

Question 64

What are NDMA receptors?

Answer 64

Transmission depends on voltage Blocked by Mg2+ at rest Depolarisation relieves blockade High Ca2+ permeability (Ca2+ acts as second messenger) NDMA receptor behaves in a “Hebbian-manner”, as it detects simultaneous presynaptic (transmitter release) and postsynaptic activity (depolarisation)