1. Clinically Relevant Functional Neuroanatomy 2: Neuroanatomy of Memory
Russell M. Bauer, Ph.D.
University of Florida, USA
Vivian Smith Summer Institute
23 June, 2006

2. Russell M. Bauer, Ph.D. (DON’T BELIEVE HIS LIES)
The Three Amnesias
Russell M. Bauer, Ph.D. (DON’T BELIEVE HIS LIES)

3. Multiple Forms of Memory

4. The Human Amnesic Syndrome
Impaired new learning (anterograde amnesia), exacerbated by increasing retention delay
Impaired recollection of events learned prior to onset of amnesia (retrograde amnesia), often in temporally graded fashion
Not limited to one sensory modality or type of material
Normal IQ, attention span, “nondeclarative” forms of memory

6. Integrated Circuitry Linking Temporal, Diencephalic, and Basal Forebrain Regions

7. Medial Temporal Syndromes
Anoxic-hypoxic syndromes
cardiac arrest
CO poisoning
Amnesia associated with ECT
CNS Infections (Herpes)
MTS and complex-partial epilepsy (material-specific)
Early AD

8. Temporal Lobe Pathology Associated with Herpes Simplex Encephalitis

9. The Case of Henry M (H.M.)

13. Bauer, Grande, & Valenstein, 2003

14. Two Limbic Circuits Lateral Medial (Papez) Anterior Thalamus
Dorsomedial Thalamus
Mamillothalamic Tract
Mammilary Bodies
Cingulate Gyrus
Orbitofrontal
Amygdalofugal pathways
Fornix
Uncus
Hippocampus
Amygdala
Lateral
Medial (Papez)

16. CA3
CA1 DG
subic

18. Bauer, Grande, & Valenstein, 2003

22. Delayed Nonmatching to Sample

23. Delayed Nonmatching to Sample, multiple trials, trial-unique objects

24. 6-8 weeks postsurgery
2 years postsurgery

26. Anterior Posterior
Zola-Morgan & Squire, 1990

27. Bauer, Grande, & Valenstein, 2003

28. Zola-Morgan & Squire, 1990

29. Murray & Richmond, Curr Opin Neurobiol, 2001
-perirhinal cortex obviously important in memory, but also apparently important in fine-grained visual discrimination

30. Two Limbic Circuits and the Two-system theory of amnesia
Anterior Thalamus
Dorsomedial Thalamus
Mamillothalamic Tract
Mammillary Bodies
Cingulate Gyrus
Orbitofrontal
Amygdalofugal pathways
Fornix
Uncus
Hippocampus
Amygdala
PRPH
Lateral
Medial (Papez)

31. Diencephalic Syndromes
Korsakoff Syndrome associated with ETOH abuse or malabsorption
prominent encoding deficits
role of frontal pathology
Vascular disease
Thalamic trauma

32. Mamillary Body Lesions in a case of Korsakoff’s Disease

34. Lesion Profile in a Case of Thalamic Amnesia

35. Graff-Radford, et al, 1990

36. Two Limbic Circuits and the Two-system theory of amnesia
Anterior Thalamus
Dorsomedial Thalamus
Mamillothalamic Tract
Mammillary Bodies
Cingulate Gyrus
Orbitofrontal
Amygdalofugal pathways
Fornix
Uncus
Hippocampus
Amygdala
Lateral
Medial (Papez)

37. Basal Forebrain Syndromes
Anterior Communicating Artery (ACoA) infarctions
prominent anterograde, variable retrograde amnesia
prominent confabulation
frontal extension of lesions
Basal forebrain and cholinergic projections to hippocampus

39. Two Limbic Circuits Lateral Medial (Papez) Anterior Thalamus
Dorsomedial Thalamus
Mamillothalamic Tract
Mammillary Bodies
Cingulate Gyrus
Orbitofrontal
Amygdalofugal pathways
Fornix
Uncus
Hippocampus
Amygdala
Lateral
Medial (Papez)

41. Two Limbic Circuits Lateral Medial (Papez) Anterior Thalamus
Dorsomedial Thalamus
Mamillothalamic Tract
Mammillary Bodies
Cingulate Gyrus
Orbitofrontal
Amygdalofugal pathways
Fornix
Uncus
Hippocampus
Amygdala
Lateral
Medial (Papez)
Bauer, Grande, & Valenstein, 2003

42. Encoding
Definition: process of transforming to-be remembered in formation into memorable and retrievable form
Encoding I: bringing information-processing capacity to bear on stimuli
Encoding II: ability to use the results of E-1 mnemonically
Relevance: levels-of-processing accounts of memory (memory as by-product of information processing)
Clinical manifestation: poor immediate (superspan) recall

43. Consolidation/Storage
definition: process of making new memories permanent
basis: anatomic and physiological changes at cellular level; hippocampal system important
when? during study-test interval
duration: hours? days? years?
clinical symptom: delayed memory << immediate memory (forgetting)

44. Retrieval
definition: process of locating, selecting, and activating a memory representation
basis: re-enactment of pattern of excitation occurring at encoding
when? at point of test
clinical symptom: recall << recognition (also true of shallow encoding), inconsistent errors

45. Key Points
Extended memory system including hippocampus, amygdala, and basal forebrain
We (basically) understand anatomy, now we need to understand computation
Notion of distinct subtypes of amnesia generally less favorable now than 10 years ago
Certain structures are ‘wired’ for associational processing; these structures are reciprocally connected to cortical processors