Case 7 - Amnesia

Question 1

Anterograde Amnesia (AA):

Answer 1

Impaired recall and recognition of recent episodic and semantic information, suggesting a problem in acquiring new long-term memories.

Question 2

Retrograde Amnesia (RA):

Answer 2

Impaired recall and recognition of information experienced before brain damage, indicating a deficit in retrieving pre-trauma memories.

Question 3

Clinical causes of amnesia:

Answer 3

Strokes: Infarctions or aneurysm rupture, especially in the anterior communicating artery.

Chronic Alcoholism (Korsakoff’s Syndrome): Damage to the midline diencephalon due to thiamine deficiency.

Head Injury: Frequent in blunt and penetrating traumas, often leading to frontal lobe damage.

Viral/Bacterial Brain Diseases: Damage to medial temporal lobes; exemplified by Clive Wearing’s case.

Hypoxia and Toxins: Resulting in damage to medial temporal lobes.

Neurosurgery: Especially for epilepsy.

Mild Cognitive Impairment and Alzheimer’s Disease: Memory disorders but not strictly amnesia.

Question 4

Preserved Functions in Amnesia:

Answer 4

Intelligence: Often unaffected, suggesting relatively normal encoding of incoming information.

Working Memory: Typically preserved; phonological loop and visuospatial scratchpad remain intact.

Perceptual Processing: Generally normal.

Attention: Usually unaffected.

Skill Learning: Preserved in many amnesiacs.

Conditioning: Preserved in most cases.

Question 5

Dual Process Model of Recognition Memory:

Answer 5

Recognition and familiarity are separate processes manipulated by different stimulus variables.

Question 6

Detecting and Measuring Amnesia:

Answer 6

Standard Neuropsychological Protocol includes orientation, working memory, immediate and delayed memory (recall and recognition), semantic memory, and remote memory.

Question 7

Selective Amnesia:

Answer 7

A form of amnesia where some aspects of explicit memory are spared while others are impaired, like selective deficit in recall, recollection, or familiarity.

Question 8

Memory and the Medial Temporal Lobe (MTL):

Answer 8

The MTL structures, including hippocampus, perirhinal, entorhinal, and parahippocampal cortices, are critical for episodic and recognition memory.

Question 9

MTL Functional Heterogeneity:

Answer 9

Agreed upon, but specific contributions of each structure in recognition memory remain unconfirmed.

Question 10

Determinants of Heterogeneity:

Answer 10

(a) Inputs each structure receives.
(b) Processes each structure carries out.

Question 11

Complex MTL System:

Answer 11

A functionally heterogeneous hierarchical system with diverse memory types.

Question 12

CRAFT - Convergent Recollection and Familiarity Theory:

Answer 12

MTL model combining lesion data, fMRI, computational models, and input/cytoarchitectonics information.

Question 13

Testing CRAFT:

Answer 13

Lesion studies, especially with patients having selective lesions, are crucial for testing the model.

Question 14

Case Study: YR

Answer 14

YR, with focal hippocampal damage, displayed normal intelligence but impaired associative memory, recollection, item memory, and familiarity.

Question 15

Associative vs. Item Memory:

Answer 15

While associative memory depends on recollection and involves the hippocampus, the relationship between item memory and the hippocampus is not straightforward.

Question 16

Item Memory Complexity:

Answer 16

Item memory may draw on hippocampal associative memory in certain conditions.
Some associations don’t depend on hippocampal associative memory.
The concept of ‘item memory’ may vary in its dependence on the hippocampus.

Question 17

Recall and Recollection Deficits is common in which type of patients?

Answer 17

Hippocampal

Question 18

Familiarity Deficits:

Answer 18

Limited human lesion evidence; more studies needed for CRAFT validation.

Question 19

Case NB - Amygdala and Perirhinal Damage:

Answer 19

Patient Profile: Young woman with epilepsy, neurosurgery on left amygdala, perirhinal, and entorhinal cortex damage.

Volume Reductions: Significant reductions in perirhinal and entorhinal cortex; hippocampus spared.

Memory Performance: Normal except for semantic phonemic fluency.

Question 20

Experimental Findings (Case NB):

Answer 20

Verbal Memory Tests: Recollection higher than average; impaired familiarity leading to false familiarity memories.

Speeded Word R/K Task: Familiarity significantly impaired even with limited associative encoding.

Confidence Ratings and ROC: Normal to above-normal recollection; significantly impaired familiarity for deeply encoded words.

Speeded Response at Test: Familiarity needed conditions showed impaired memory.

Question 21

Testing NB with Non-Verbal Materials:

Answer 21

Abstract Art, Faces, Auditory Words: Similar tests applied to non-verbal stimuli.

Question 22

Overlearned Memory Processes:

Answer 22

Exploration of how processes of overlearned lifetime familiarity memory relate to standard familiarity paradigms.