1. Fractionation of Memory in Medial Temporal Lobe Amnesia
Chris M. Bird
Tim Shallice
Lisa Cipolotti

2. Who? RH Female 58-year-old housewife Right-sided hippocampal damage
Intact cognitive profile apart from selective memory impairments

3. What Went Wrong? 1996 However
Sudden onset tingling, weakness in the left arm
Impairment in remembering events, appointments, conversations
Difficulty with her sense of direction – esp. in unfamiliar places
However
NO difficulty in remembering names & faces
NO difficulty in recognizing familiar places or landmarks
Neurological examination - normal

4. Nature of the Damage T1 weighted images
selective atrophy of right hippocampal formation (focused volume loss)
Enlargement of the right lateral ventricle
NO abnormalities in left hippocampus
Other temporal lobe areas appeared normal

5. Nature of the Damage
Brain volume calculated to be within normal range  no evidence of widespread atrophy
Left hippocampus volume = 2654 mm3
Right hippocampus volume = 1100 mm3
Right hippocampus markedly small – 58.6% smaller

6. Specific Aspects of Memory Impaired
2 assessments, 1 year apart
March 2003 & March 2004
Results
General Cognitive Assessment
Verbal & Performance IQ – remarkably similar scores
Nominal Skills, Visual, & Visuospatial perception – normal
GNT, Object decision, Cube analysis, Number location
Executive processing – normal
WCST, Verbal fluency

7. Specific Aspects of Memory Impaired
Results
Semantic Memory Assessment
Category specific naming test – normal
Able to name all famous buildings, 9/12 famous faces
Category fluency – normal
8 semantic categories, 3 phonemic categories
3 comprehension tests – satisfactory
Intact performance on general intelligence, focal language, perception, executive tasks, and extensive semantic memory battery  no cognitive decline

8. Specific Aspects of Memory Impaired
Results
Anterograde memory assessment
Story recall tests – weak
Paired associate learning test – lower end of normal range
Visual recall – clearly impaired
Rey-Osterreith complex figure
Failed at learning a spatial supraspan
Recognition Memory Test – normal
Suggests preserved recognition memory for verbal material & unfamiliar human faces

9. Specific Aspects of Memory Impaired
Results
Anterograde memory assessment cont’d
Topographical Recognition Memory Test – poor
Pictures of outdoor urban scenes
Overall, verbal recall & recognition memory (human faces) tests – normal range
Tests of story recall - poor

10. Specific Aspects of Memory Impaired
Results
Doors & People Test
Verbal Subtests
Immediate – intact
Delayed – impaired
Recognition – satisfactory
Visual Subtests
Immediate – impaired
Intact verbal recall & recognition memory
Impaired visual recall

11. What can we learn from this?
Left hippocampus is sufficient to serve both recollection & familiarity of some verbal memoranda
Right hippocampus necessary for recollection & familiarity for topographical materials
Recognition memory for unknown faces not dependent on hippocampus, may depend on other structures

12. Discussion Outlook Unclear
Data from this study appear to support earlier studies that hippocampus plays role in both recollection & familiarity
Word of caution on drawing strong conclusions about the neuroanatomy of recollection & familiarity
Unclear
Which aspects of non-verbal memory can be mediated successfully by areas outside the hippocampus?
What treatments are out there that can improve, possibly bring back, non-verbal memory abilities in patients with extensive MTL damage?

13. Questions?