1. Secondary (Recent) Memory

2. Declarative Memory Knowing that Explicit knowledge
Tulving: Two subdivisions
i) Semantic
ii) Episodic

3. Episodic Memory ***Typically disrupted in amnestic conditions
Memories that depend on temporal, spatial or contextual cues in order the retrieve the information (= explicit memory)
Consists of additional knowledge of personal experience
Involves remembering specific events and episodes in the context in which they occur
***Typically disrupted in amnestic conditions

4. Measures of Episodic Memory
Numerous
Examples:
WMS-IV/WMS-III: Paired Associates, Logical Memory, Visual Reproduction, Designs
Rey Complex Figure
RAVLT/CVLT/SRT

7. Selective Reminding Test

8. A taxonomy of memory disorders

9. Cerebral hemispheres

10. Material Specific Memory Disorder
Reflection of lesion laterality – Pathology of the dominant V’s nondominant hemipshere
Temporal Lobe Epilepsy (TLE)
Milner (1958, 1962): Patients undergoing unilateral temporal lobe resection for relief of intractable complex partial seizures
Temporal lobectomy: Anterior portion (5cm) of temporal lobe removed including the anterior portion of the hippocampus
Memory Disorder: Material specific not modality specific

11. Left TL resection: Verbal Memory Deficit (logical memory, word lists)
Right TL resection: Nonverbal Memory Deficit
(maze learning, design recall, recall of faces)
Hippocampus thought to be the important structure

14. TLE – Case Example Case: KE Age: 19 years Sex: Female
History: 6 month history of complex partial seizures
Eduction: HSC graduate, Commenced first year of a degree in PE teaching – deferred due to memory problems

15. Index
Index Score
Verbal Comprehension
101
Perceptual Reasoning
108
Working Memory
109
Processing Speed 95
Full Scale
General Ability
1`05

16. KA: Wechsler Memory Scale-IV (WMS-IV)
Index Score
Auditory Memory 87
Visual Memory 105
Visual Working Memory 109
Immediate Memory 95
Delayed Memory 71

17. KA: Further Memory Testing
Selective Reminding Test
CLTR = 50 (Mean = 115, SD = 15.5)
Recognition Memory Test
Scale Score
Words 5
Faces 11
15-Item Visual Memory Test
Raw score = 15/15

18. 15-Item Visual Memory Test
A B C
I II III
  
a b c

19. KA: Assessment of adaptive abilities
Controlled Oral Word Association Test (COWAT)
Words = 39 (Mean = 41.5, SD = 6.7)
Wisconsin Card Sorting Test
Categories = 6
Perseverative Responses = 11
Rey Complex Figure Test
Copy = 34, Recall = 22
Booklet Category Test
Errors = 23

20. KA: Rey Figure Copy

21. KA: Rey Figure Recall

22. Material Specific Disorders of Memory (con’t)
2. Cerebrovascular Disorders
Disruption of brain function secondary to vascular pathology (includes haemorrhage (rupture), narrowing (stenosis) and occlusion due to presence of an obstructing clot (thrombus or embolus)
Branches of the posterior cerebral artery supply the inferior and medial surfaces of the temporal lobes and posterior sections of the hippocampus. Thus, infarction (tissue death) may result from occlusion and produce a material specific memory disorder
Unilateral thalamic infarction (secondary to PCA disturbance) may also produce a material specific disorder of memory.

23. Specific Disorders of Memory
Topographical disorientation
Damage to the right tempero-parietal areas (MCA)
Unable to find way around.
Tactile Memory
Impairment reported in patients with unilateral temporal lobe lesion resulting from CVA with loss demonstrated in hand contralateral to the lesion.

24. BS: Lateralised (R.Hem) Dysfunction
45 yo female
9 years education
DSS (clerical) for 17 years
3-4 months preceding ABI worked as a taxi driver
1/1/02 assaulted during the course of her work
PTA: several days duration (no recollection of visitors while in hospital, son receiving HSC results)

25. CT (2006): Local area of enlargement of the temporal horn of the right lateral ventricle, enlargement of the right Sylvian fissure. Appearances consistent with an area of local atrophy.
Psych Tx for PTSD
Psychiatrist noted that she intermittently complained of memory problems and geographical disorientation

26. Case BD Assessment February 2007 Attended unaccompanied
Fully cooperative
c/o - memory problems (eg. Forgets where she is meant to be driving to, gets lost even when driving to familiar places, misplaces her personal belongings)
- irritability

27. WAIS-IV Verbal IQ = 116 PIQ = 110 Working Memory = 117
Processing Speed = 104
Full Scale IQ = 111
General Ability = 113

28. WMS-IV INDEX ACTUAL PREDICTED Auditory Mem 103 106 Visual Mem 75
Visual Working Mem
108
107
Immediate Mem _
Delayed Mem

29. Base Rates (General Ability)
AM - >25%
VM - <1%

30. BD: Additional Memory Tests
Selective Reminding Test
Consistent Long-Term Retrieval – Average
Rey Complex Figure Test
Copy = 25
Recall = 4.5 (<1st percentile)

31. BD: Adaptive Abilities and Emotional Status
Trail Making Test
Part A = 26 seconds, 0 errors
Part B = 50 seconds, 0 errors
Controlled Oral Words Association Test (COWAT)
Words = 45, Errors = 3
Wisconsin Card Sorting Test
Categories = 6, Errors = 12
Perseverative Responses = 6 (Above Average)
Booklet Category Test
Errors = 107 (Impaired)
Depression, Anxiety, Stress Scales
Depression = 40 (Ex.S.),
Anxiety = 36 (Ex.S.), Stress = 32 (Ex.S.)

32. BD: Opinion
The results of the assessment revealed clear evidence of cognitive impairment. Although generally able to achieve at an average to high average level on measures of verbal ability, her nonverbal skills proved markedly disordered. Specifically, she demonstrated difficulty in acquiring, retaining and processing visuospatial material. Although she is clearly suffering significant levels of emotional distress, reference to these factors alone would not appear to be sufficient to account for all of the deficits seen on testing.

33. Neither depression nor anxiety would be expected to produce a material-specific disorder of memory and adaptive ability. A disparity between performance on measures of verbal and nonverbal ability, when of the magnitude that was evident in the present case, is strongly suggestive of lateralised cerebral pathology. The profile of performances returned on testing would suggest that there has been damage to the frontal and temporal lobes of the nondominant (right) hemisphere. The CT report provides independent evidence of focal damage to these areas.

34. BD: Opinion (con’t)
Given the results of the assessment it is not surprising to learn that BD complains of a tendency to get lost while driving and occasion geographic disorientation. The ability to remember routes and to understand spatial relations is known to be mediated by the right hemisphere. Recalling the temporal detail of various events is thought to represent one of the functions that is subserved by the frontal lobes. As stated above, the results would suggest that these areas have been damaged.

35. BD: Opinion (con’t)
On a day to day level BD’s deficits are most likely to manifest as a difficulty in recalling visual information (scenes, routes, faces etc), a difficulty in planning her approach to nonverbal tasks (eg. when assembling an item or dealing with procedures that involve a number of steps) and an inability to reason and problem-solve in the nonverbal modality. She may experience difficulty in learning the requirements of any new position, particularly if the work involves nonverbal displays or tasks. She should be encouraged to verbalise information and to make written note of new procedures. Her ability to operate a computer may be

36. compromised in that she is likely to find it difficult to remember the meaning of various symbols and the full range of responses that a particular visual cue is designed to elicit. Even when her mistakes are drawn to her attention she is likely to have difficulty in generating some alternative method of response. Modelling of the correct procedure would be of use. Flow-charts or other nonverbal displays are unlikely to be of assistance.

39. Frontal Amnesia A. Organisational Deficits
Simple registration and recall not affected by frontal lesions
Memory problems may be secondary to an inability to organise material for the purpose of committing it to memory
i.e. failure to impose a meaningful structure on the information, to generate appropriate learning strategies
Frequent concomitant of traumatic brain injury
Manifest on tests such as Rey Complex Figure, Rey Auditory Verbal Learning

42. Frontal Amnesia B. Retrieval Problems
Retrieval involves strategic problem-solving. Often disturbed following frontal lesions
Patient with a retrieval deficit will demonstrate a disturbance of free recall
Recognition memory should, however, be intact
eg. RAVLT: poor score on recall of list A (trials 1-6)
recognition 15/15
One advantage of WMS-III relative to WMS-R

43. Frontal Amnesia C. Temporal Discrimination
Increasing attention being devoted to this aspect of memory
Patients with frontal lesions are markedly impaired in making temporal discriminations. Great difficulty in judging recency and temporal order and in reconstructing sequences.
Note, deficits of temporal ordering may be seen in the absence of fontal lobe pathology
Two processes involved:
Encoding of information needed for temporal memory
Effective processing of retrieved information regarding temporal order
In patients with lesions of the frontal lobes deficit lies in b) ie. Is one of faulty processing (c.f. WKS patients where the deficit lies in a)).

44. General Amnesic Syndrome
Definition
A permanent, stable and global disorder of memory due to organic brain dysfunction which occurs in the absence of any other extensive perceptual or cognitive disturbance.
NB. Permanency
Stability
Pervasiveness
Specificity

45. Clinical Features of the Amnesic Syndrome
Profound difficulty or total inability to acquire new material (anterograde amnesia)
Preservation of immediate memory as measured by tasks such as digit span
Preservation of semantic memory
Preservation of procedural learning
Some retrograde amnesia (variable across patients)

46. Neuopathology Brain structures implicated:
Bilateral damage to the mesial temporal lobes of both the right and left hemispheres
Within these areas the hippocampus has been seen to represent the crucial structure
2. Structures within the diencephalon and specifically:
Nuclei within the thalamus
Mamillary bodies
Mamillo-thalamic tract
Fornix
All above structures represent part of the limbic system

48. Aetiology GAS typically seen in association with
Wernicke-Korsakoff Syndrome
Herpes Simplex Encephalitis
Hypoxia
Anterior Communicating Artery Aneurysm
Thalamic Infarction
Temporal Lobe Resection
Other causes:
CVA
Tumour

50. Wernicke-Korsakoff Syndrome
Typically the result of chronic alcoholism
Principle cause: Thiamine deficiency
Results in damage to the subcortical structures and in particular the diencephalon
Minimal requirement: Lesion of the mamillary bodies and dorsomedial nucleus of the thalamus
Typically additional lesions in the frontal lobes (atrophy) due to alcohol neurotoxicity and often the medial temporal structures including the hippocampus
Treatment. Thiamine. Amnesia often persists

51. WKS: Characteristics Normal memory span Severe anterograde amnesia
Normal rate of forgetting
Extensive, temporally graded retrograde amnesia
Confabulation present
Cued recall better than spontaneous recall
Recognition relatively intact
Poor at recency judgements
Frontal lobe dysfunction typically present