Memory and amnesia

Question 1

Memory

Answer 1

Refers to our ability acquire, retain and retrieve information

Question 2

System approach of memory

Answer 2

view that different types of memory are located in different regions of the brain

Question 3

Process approach of memory

Answer 3

view that memory is composed of different processes that may recruit similar or different neural regions depending on the task facing the individual.

Question 4

Working memory

Answer 4

A form of short-term memory which allows a paean ro hold and manipulate a certain amount of information for a few seconds after it has been presented.

Question 5

Modal model of memory

Answer 5

Atkinson and Shifrin

Distinguish between

• “sensory memory store” (store sensory impression for very brief period of time).
• “Short term memory store” (which can hold information over longer periods through mental rehearsal).
• “long term memory store” (information is passed following processing by the short-term store)

The model propose that the memory stores/systems are unitary (no subcomponents). The concept of unitary STM has a number of problems, and an alternative model (multi-component model) was suggested - baddely

Question 6

Multi-component model

Answer 6

Baddely.

The model is referred to as “working memory”. Consist of:

• Central executive: directs and regulate the flow of information and allocate attention and processing operations within the two slave systems (they are controlled by the CE)
• Visuospatial sketchpad: integrate and process spatial and visual information over short periods.
• Phonological loop: store and processing verbal auditory information over short periods)

Question 7

Corsi block test

Answer 7

To test visuospatial memory.
9 identical blocks are arranged in front of the participant, and the experimenter taps the block in a particular sequence, then the participant has to reproduce the same sequence.

Measures visuospatial WM, since the participant has to retain the spatial sequence in order to reproduce it accurately.

Damage: right posterior parietal region > did poor in this task.

Question 8

Corsi block test (damage)

Answer 8

Right posterior parietal region

Question 9

Visuospatial damage:

Answer 9

Damage to anterior temporal lobes impair visual WM, while leaving spatial WM intact. Damage to parietal lobe selectively impairs spatial memory taks. This double dissociation is strong evidence that the visuospatial sketchpad Neds to be subdivided into separate visual and spatial components.

Question 10

Phonological loop

Answer 10

Consist of:

• Phonological store (temporary storage of speech-based sounds. It decays unless refreshed by the articulatory control process)
• Articulatory control process

Question 11

Episodic buffer

Answer 11

Was later added.

It is able to hold and integrate relatively large amounts of information over short periods and as a ‘backup’ store which communicates with both long-term memory and the components of working memory.

Question 12

Central executive area

Answer 12

Dorsolateral prefrontal regions

Question 13

Amnesia

Answer 13

General term for memory loss. two subtypes, anterograde and retrograde amnesia

Question 14

Anterograde amnesia

Answer 14

Memory deficit for the acquisition of new information or new learning since the time of the brain damage.

New events are not stored in LTM.

Question 15

Anteriograde amnesia (location)

Answer 15

Medial temporal lobe and associated structures such as hippocampus, dentate gyrus and the parahippocampal cortex.

Question 16

Reterograde amnesia

Answer 16

Impairment in remembering information from the time prior to the onset of the damage.

Question 17

HM (case study)

Answer 17

Perhaps the most famous case of anterior grade amnesia.

He suffered from epilepsy, surgically removed much of the medial temporal lobe regions in both hemisphere. this left him with a severe form of AA. Despite this, his IQ and language perception was above normal.

Question 18

Causes of amnesia

Answer 18

The Korsakoff syndrome
Hypoxia
Vascular disorders
Head injuries 
Viral infections

Question 19

The korsakoff syndrome

Answer 19

A cause of amnesia

Result from nutritional deficiency that is often associated with chronic alcoholism, because it interferes with the transport of the vitamin “thiamine” which plays an important role in cerebral metabolism.

Question 20

Hypoxia

Answer 20

Inadequate supply of oxygen to the tissue, and can result from heart disorder, carbon monoxide poisoning etc.

Question 21

Declarative memory

Answer 21

explicit

Refers to memory for events, episodes, and facts.

Question 22

Non-declarative memory

Answer 22

Implicit

Form of memory that is observed and expressed through performance without any necessary awareness. They use memory without any conscious awareness, e.g. riding a bicycle.

Question 23

Priming

Answer 23

The influence of preliminary event/stimulus on subsequent responding.

Does not require awareness (implicit).

people with anterior grade amnesia, can do good on stem completion task when primed with a word in advance.

if a word is heard, then tested visually, then priming is reduced which may indicate that priming is dependent on neural regions involving vision and perception.

Question 24

Neural signature of priming effects

Answer 24

When individuals are required to make conceptual or semantic judgments about words, the left prefrontal cortex became activated. When asked alter to make the same judgment to the words, a relative decrease in the activation was observed in this same area.

Question 25

Classical conditioning

Answer 25

Non-declarative memory

Amnesic individuals with damage to the mediotemporal lobe had no difficulty in learning the conditioned eye blink response in spite of profound declarative memory impairments.

Question 26

Non-declarative memory (location, specific classical conditioning)

Answer 26

The cerebellum seems to be the critical neural region for classical conditioning type of non-declarative memory. Patient with damage to this region were impaired at acquiring the classically conditioned eye blink response.

This area is also susceptible to toxic from prenatal alcohol exposure, hence children of prenatal alcohol exposure did poor in learning classically conditioned eye blink response.

Question 27

Implicit learning

Answer 27

learning without awareness.

Experiment: push a button when they see the light. People often do better after several tasks (implicit learned), hoewver, amnesic individuals indicate that their performance on this task is spared despite profound recognition memory deficits.

Question 28

Declarative memory (location)

Answer 28

Medial temporal lobe

Question 29

Episodic memory

Answer 29

Memory for events

Question 30

Semantic memory

Answer 30

Memory for facts

Question 31

The role of hippcomapus

Answer 31

Important for declarative memory. Can be distinguished between familiarity and recollection.

Question 32

Diencephalon and amnesia

Answer 32

Diencephalon (thalamus+hypothalamus + maxillary bodies) typically results in memory impariemtns.

Question 33

Encoding

Answer 33

Refers to those cognitive activities or processes that are responsible for creating a representation of the events or episode to be remembered.

Question 34

Regions active in deep processing

Answer 34

Hippocampus, adjacent MTL regions and the prefrontal cortex. Some studies have found hemispheric differences such that greater left (vs right) activations are typical when the stimuli are words (vs pattern).

Question 35

Deep processing

Answer 35

Associated with enhanced memory and enhanced activations in particular neural regions.

Deep encoding led to greater activation in left medial temporal lobes and the left lateral prefrontal cortex.

Question 36

Retrieval

Answer 36

Refers to accessing information stored in memory. it can be broken down into a number of subcomponents called retrieval mode, ecphory and recollection.

Question 37

Retrieval mode

Answer 37

Right prefrontal cortex is active during retrieval.

It refers to a form of “mental set” in which the individual directs attention to the act of remembering, and makes use of cues in order to recall information.

Question 38

Ecphory

Answer 38

Difficult to distinguish from “recollection”. –> Recollection is when the individual becomes aware of the information retrieved.

Its the interaction between the retrieval cue and the stored memory trace.

Question 39

Transfer appropriate processing (TAP)

Answer 39

when encoding and retrieval processes interact.
TAP states that the most important factor in successful memory is the extent to which encoding and retrieval processes overlap. if retrieval processes overlap the same mental processes that occurred during encoding, then memory will be successful.

Question 40

Hemispheric encoding and retrieval asymmetri (HERA)

Answer 40

Was meant to summarize a number of findings indicating that the left prefrontal region showed greater activation during encoding while the right prefrontal region showed greater activation during retrieval.

Question 41

Focal retrograde amnesia

Answer 41

If it occurs in isolation. Reterograde amnesia can often co-occure with anterograde amnesia.

Impairments are greatest for more recent events leading up to the injury or disease, which produce a situation in which memory for more distant event, such as those in childhood is actually better than memory for more recent events.

Question 42

Autobiographical (areas)

Answer 42

Activates a network of areas including temporal and parietal regions, the medial frontal cortex, the cerebellum, and the hippocampus.

Question 43

Hippocampus (retrograd amnesia)

Answer 43

Its responsible for retrieving only relatively recent memories. Memory from childhood f.ex can be retrieved without hippocampus because of the consolidation process (which strengthen and makes memory stable).

When lesion to hippocampus, memory was impaired for the objects learned a few days before and was best for those acquired weeks before.

Question 44

Long term potential (LTP)

Answer 44

A candidate to be responsible for consolidation of memory, and refers to the increased magnitude of the response of the postsynaptic neuron following stimulation by the presynaptic neuron. This increased response can be shown to last for hours and thus represent the record of previous neuronal activity.

LTP occurs in hippocampus and in the cortex.