Chapter 31 - Memory

Question 1

Humans have at least two qualitatively different systems of information storage. These are generally referred to as ..

Answer 1

1. declarative memory

2. nondeclarative memory

Question 2

Humans have at least two qualitatively different systems of information storage. These are generally referred to as declarative memory and nondeclarative memory. What is declarative memory?

Answer 2

Declarative memory is the storage and retrieval of material that is available to consciousness and can in principle be expressed by language (i.e. “declared”).

Question 3

Humans have at least two qualitatively different systems of information storage. These are generally referred to as declarative memory and non declarative memory. What is nondeclarative memory?

Answer 3

Nondeclarative memory (also referred to as procedural memory) is not available to consciousness, at least not in any detail. Such memories involve skills and associations that are, but large, acquired and retrieved at an unconscious level.

Question 4

The ability to remember a phone number is an example of …. memory

Answer 4

Declarative

Question 5

Knowing how to use your phone to dial a number is an example of …… memory

Answer 5

Nondeclarative

Question 6

In addition to the types of memory defined by the nature of what is remembered, memory can also be categorised …

Answer 6

Memory can also be categorised according to the time over which it is effective.

Question 7

Three temporal classes of memory are generally accepted. Which?

Answer 7

1. Immediate memory
2. Working memory
3. Long-term memory

Question 8

What is meant by immediate memory, a temporal class of memory?

Answer 8

Immediate memory is the routine ability to hold ongoing experiences in mind for fractions of a second.

Question 9

How is the capacity of immediate memory?

Answer 9

The capacity of immediate memory is very large, and each sensory modality appears to have its own semi-independent “memory register”.

Question 10

What is meant by working memory, a temporal class of memory?

Answer 10

Working memory is the ability to hold and manipulate information in mind for seconds to minutes while it is used to achieve a particular goal.

Question 11

What is meant by long-term memory, a temporal class of memory?

Answer 11

Long-term memory entails retaining information in a more permanent form of storage for days, weeks, or even a lifetime.

Question 12

What is an engram?

Answer 12

Engram is the physical embodiment of any memory in the neuronal machinery. (I think it’s a cognitive psychology term)

Question 13

The way in which immediate and short-term memories are gradually encoded as long-term memories is called..

Answer 13

memory consolidation.

Question 14

Mention two experiments on priming that is relevant for memory consolidation.

Answer 14

1. In a commonly used test, the subject is presented at time 1 with a list of words to study and is later tested using a word-stem completion task. The stems could also be completed from list B, which comprises words the subject did not see during the initial session. Subjects typically complete the stems with about 25% more studied that unstudied words; this percentage represents the effect of priming.
2. The information stored in priming is not particularly reliable. A list of nouns of sweet objects is read aloud to a subject, and they are later asked to write down as many as they can remember from this list. Typically, about half the students report that the word “sweet” was included in the list, even though it was not.

Question 15

Give examples on how meaning influences memory.

Answer 15

1. The person who holds the world record for remembering the most digits of pi (67, 000), did so by associating the digits with musical notes and singing the number strings.
2. A college student who was paid to remember randomly presented numbers increased his skill by associating the numbers with dates or times at track meets (he was a runner).

Question 16

What is conditioned learning?

Answer 16

The generation of a novel response that is gradually elicited by repeatedly pairing a novel stimulus with a stimulus that normally elicits the response being studied.

Question 17

Which forms of conditioned learning do we know of?

Answer 17

1. Classical conditioning

2. Operant conditioning

Question 18

What is classical conditioning?

Answer 18

Classical conditioning occurs when an innate reflex is modified by associating its normal triggering stimulus with an unrelated stimulus; by virtue of the repeated association, the unrelated stimulus eventually triggers the original response.

Question 19

Classical conditioning was famously demonstrated by whom?

Answer 19

The Russian psychologist Ivan Pavlov.

Question 20

What is operant conditioning?

Answer 20

Operant conditioning refers to the altered probability of a behavioural response produced by associating the response with a reward.

Question 21

What is the most famous study on operant conditoning?

Answer 21

Frederick Skinner’s experiments at Harvard, where pigeons or rats learned to associate pressing a lever with receiving a food pellet.

Question 22

If the conditioned animal performs the desired response but the reward is no longer provided, the conditioning gradually disappears, a phenomenon called…

Answer 22

extinction.

Question 23

The ability to forget unimportant information may be critical for normal life. Although forgetting is a normal and essential mental process, it can also be pathological, a condition called ..

Answer 23

amnesia

Question 24

Two different types of amnesia. Which?

Answer 24

1. Anterograde amnesia

2. Retrograde amnesia

Question 25

What is anterograde amnesia?

Answer 25

Anterograde amnesia is an inability to establish new memories.

Question 26

What is retrograde amnesia?

Answer 26

Retrograde amnesia is a difficulty retrieving memories.

Question 27

Which structures are associated with declarative memory disorders?

Answer 27

1. Thalamus
2. Hippocampus
3. Fornix
4. Amygdala
5. Mammillary body

Question 28

The hippocampus is located …

Answer 28

In the medial temporal lobe.

Question 29

There is an idea that long-term memory traces are distributed over the entire cortex. This was studied by Karl Lashley in the 1920s. What were his findings?

Answer 29

Lashley worked with rats and maze-learning whilst removing cortex. He summarised his findings in terms of what he called the mass action principle, which states that any degradation in learning and memory depends on the amount of cortex destroyed; and that the more complex the learning task, the more disruptive the lesion.

Question 30

“fun” fact: how was electroconvulsive therapy invented?

Answer 30

This remarkably useful treatment was discovered because depression in epileptics often remitted after a spontaneous seizure.

Question 31

What are common negative consequences of electroconvulsive therapy?

Answer 31

ECT often causes both anterograde and retrograde amnesia. Patients typically do not remember the treatment itself or the events of the preceding days, and their recall of events over the previous 1-3 years can be affected.

Question 32

How does our knowledge of electroconvulsive therapy aid us in our quest for knowledge of the localisation of memory?

Answer 32

The nature of amnesia following ECT supports the conclusion that long-term declarative memories are widely stored in the cerebral cortex, since the sis the part of the brain predominantly affected by this therapy.

Question 33

The retrieval of memories appears to involve which parts of the cortex?

Answer 33

The association cortexes, particularly the frontal cortex.

Question 34

Patients such as H.M., N.A., and R.B. had no difficulties establishing or recalling nondeclarative memories, indicating that such information is laid down using a different anatomical substrate from that used in declarative memory formation. Nondeclarative memory apparently involves …

Answer 34

.. the basal ganglia, prefrontal cortex, amygdala, sensory association cortexes, and cerebellum - but not the medial temporal lobe or midline diencephalon.

Question 35

Simple sensory-motor conditioning such as learning to blink following a tone that predicts a puff of air directed at the eye is severely reduced if ..

Answer 35

If the patient has suffered damage to the cerebellum.

Question 36

Learning new motor skills is incredibly difficult if you have suffered damage to …

Answer 36

the basal ganglia and prefrontal cortex.

Question 37

Memory and Aging. What is the most obvious way, post-mortem, you can see the brain deterioration from aging?

Answer 37

The average weight of the normal human brain steadily decreases from early adulthood onward.

Question 38

What is dementia?

Answer 38

Dementia is a syndrome characterised by failure of recent memory and other intellectual functions. It is usually insidious(stealthy) in onset but tends to progress steadily.

Question 39

What is the most common dementia?

Answer 39

Alzheimer’s disease is the most common dementia, accounting for 60-80% of cases in the elderly.

Question 40

Alzheimer’s disease afflicts a percentage of the U.S. population. X%

Answer 40

5-10%

Question 41

How many percent of the population over 85 years suffer from alzheimer’s disease?

Answer 41

45%.

Question 42

What are the earliest signs of Alzheimer’s disease?

Answer 42

Impairment of recent memory function and attention, followed by failure of language skills, visual-spatial orientation, abstract thinking and judgement.

Question 43

A tentative diagnosis of Alzheimer’s disease is based on characteristic clinical features, but can only be confirmed by the distinctive cellular pathology evident in the post mortem brain. What are these histopathological changes?

Answer 43

1. Collections of intraneuronal cytoskeletal filaments called neurofibrillary tangles.
2. Extracellular deposits of an abnormal proteins (called amyloid) in so-called senile plaques.
3. A diffuse loss of neurons.

Question 44

The histopathological changes present in the Alzheimer brain are most prominent in which structures?

Answer 44

1. Neocortex
2. Limbic structures
3. Brainstem nuclei

Question 45

Which structures are limbic structures?

Answer 45

1. Hippocampus
2. Amygdala
3. The cortices associated with those two.

Question 46

What seems to cause the early-onset AD?

Answer 46

Mutations of the APP (amyloid precursor protein) gene on chromosome 21.

Question 47

Why did researchers look at chromosome 21 for the cause of the early-onset AD?

Answer 47

Investigators long suspected that a mutant gene responsible for familial AD might reside on chromosome 21, primarily because clinical and neuropathology features similar to AD often occur in individuals with Down syndrome (which is caused by an extra copy of chromosome 21), but with a much earlier onset.

Question 48

What is apolipoprotein E (ApoE)?

Answer 48

Apolipoprotein E is a protein that normally chaperones cholesterol through the bloodstream. Warren Strittmatter and Guy Salvesen discovered this protein when they took the CSF of Alzheimer’s patients and mixed it with amyloid beta. Apolipoprotein E was found to bind to amyloid with great affinity.

Question 49

What is a protein isoform?

Answer 49

A protein isoform is any of several different forms of the same protein. Different forms of a protein may be produced from very closely related gene duplicates.

Question 50

Apolipoprotein E was found to bind to amyloid beta. Margaret Periack-Vance, Allen Roses and their colleagues had an interesting finding as well. What was it?

Answer 50

They found that affected members of some families with the late-onset form of Ad exhibited an association with genetic markers on chromosome 19. This finding was of particular interest because a gene encoding an isoform of ApoE is located in the same region of chromosome 19 implicated by the association studies.

Question 51

ApoE has how many alleles?

Answer 51

It has three major alleles: e2, e3, and e4.

Question 52

How do late-onset AD patients differ in their alleles for ApoE?

Answer 52

The frequency of allele e4 in the general population is 0.14, but in late-onset AD patients it’s 0.52.

Question 53

How many percent of individuals that have no alleles of e4 develop AD by age 75?

Answer 53

20%

Question 54

How many percent of individuals that have two copies of allele e4 develop Alzheimer by age 75?

Answer 54

90%

Question 55

Inheriting the e4 form of ApoE means you will get AD?

Answer 55

No. It increases the risk, and especially if you have both copies of it. But it’s not definitive.

Question 56

Short: What is the Fornix?

Answer 56

The fornix (Latin: arch) is a C-shaped bundle of nerve fibers in the brain that carries signals from the hippocampus to the mammillary bodies and then to the anterior nuclei of thalamus.

Question 57

Short: What is the mammilary body?

Answer 57

The mammillary bodies are a pair of small round bodies, located on the undersurface of the brain that, as part of the diencephalon, form part of the limbic system. They are located at the ends of the anterior arches of the fornix. Neuroanatomists have often categorized the mammillary bodies as part of the hypothalamus.