clinically relevant functional neuroanatomy 2: neuroanatomy of memory

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Clinically Relevant Functional Neuroanatomy 2: Neuroanatomy of Memory Russell M. Bauer, Ph.D. University of Florida Functional Human Neuroanatomy 3 August, 2006

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Clinically Relevant Functional Neuroanatomy 2: Neuroanatomy of Memory. Russell M. Bauer, Ph.D. University of Florida Functional Human Neuroanatomy 3 August, 2006. The Three Amnesias. Russell M. Bauer, Ph.D. (DON’T BELIEVE HIS LIES). Multiple Forms of Memory. The Human Amnesic Syndrome. - PowerPoint PPT Presentation

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  • Clinically Relevant Functional Neuroanatomy 2: Neuroanatomy of MemoryRussell M. Bauer, Ph.D.University of FloridaFunctional Human Neuroanatomy3 August, 2006

  • The Three AmnesiasRussell M. Bauer, Ph.D. (DONT BELIEVE HIS LIES)

  • Multiple Forms of Memory

  • The Human Amnesic SyndromeImpaired new learning (anterograde amnesia), exacerbated by increasing retention delayImpaired recollection of events learned prior to onset of amnesia (retrograde amnesia), often in temporally graded fashionNot limited to one sensory modality or type of materialNormal IQ, attention span, nondeclarative forms of memory

  • Integrated Circuitry Linking Temporal, Diencephalic, and Basal Forebrain Regions

  • Medial Temporal SyndromesAnoxic-hypoxic syndromescardiac arrestCO poisoningAmnesia associated with ECTCNS Infections (Herpes)MTS and complex-partial epilepsy (material-specific)Early AD

  • Temporal Lobe Pathology Associated with Herpes Simplex Encephalitis

  • The Case of Henry M (H.M.)

  • Bauer, Grande, & Valenstein, 2003

  • HippocampusMammilary BodiesAnterior ThalamusCingulate GyrusFornixMamillothalamic TractAmygdalaDorsomedial ThalamusOrbitofrontalUncusTwo Limbic CircuitsMedial (Papez)LateralAmygdalofugal pathways

  • DGCA3CA1subic

  • Bauer, Grande, & Valenstein, 2003

  • Delayed Nonmatching to Sample

  • Delayed Nonmatching to Sample, multiple trials, trial-unique objects

  • 6-8 weeks postsurgery2 years postsurgery

  • Zola-Morgan & Squire, 1990Anterior Posterior

  • Bauer, Grande, & Valenstein, 2003

  • Zola-Morgan & Squire, 1990

  • Murray & Richmond, Curr Opin Neurobiol, 2001

    -perirhinal cortex obviously important in memory, but also apparently important in fine-grained visual discrimination

  • HippocampusMammillary BodiesAnterior ThalamusCingulate GyrusFornixMamillothalamic TractAmygdalaDorsomedial ThalamusOrbitofrontalUncusTwo Limbic Circuits and the Two-system theory of amnesiaMedial (Papez)LateralAmygdalofugal pathwaysPRPH

  • Diencephalic SyndromesKorsakoff Syndrome associated with ETOH abuse or malabsorptionprominent encoding deficitsrole of frontal pathologyVascular diseaseThalamic trauma

  • Mamillary Body Lesions in a case of Korsakoffs Disease

  • Lesion Profile in a Case of Thalamic Amnesia

  • Graff-Radford, et al, 1990

  • HippocampusMammillary BodiesAnterior ThalamusCingulate GyrusFornixMamillothalamic TractAmygdalaDorsomedial ThalamusOrbitofrontalUncusTwo Limbic Circuits and theTwo-system theory of amnesiaMedial (Papez)LateralAmygdalofugal pathways

  • Basal Forebrain SyndromesAnterior Communicating Artery (ACoA) infarctionsprominent anterograde, variable retrograde amnesiaprominent confabulationfrontal extension of lesionsBasal forebrain and cholinergic projections to hippocampus

  • HippocampusMammillary BodiesAnterior ThalamusCingulate GyrusFornixMamillothalamic TractAmygdalaDorsomedial ThalamusOrbitofrontalUncusTwo Limbic CircuitsMedial (Papez)LateralAmygdalofugal pathways

  • HippocampusMammillary BodiesAnterior ThalamusCingulate GyrusFornixMamillothalamic TractAmygdalaDorsomedial ThalamusOrbitofrontalUncusTwo Limbic CircuitsMedial (Papez)LateralAmygdalofugal pathwaysBauer, Grande, & Valenstein, 2003

  • EncodingDefinition: process of transforming to-be remembered in formation into memorable and retrievable formEncoding I: bringing information-processing capacity to bear on stimuliEncoding II: ability to use the results of E-1 mnemonicallyRelevance: levels-of-processing accounts of memory (memory as by-product of information processing)Clinical manifestation: poor immediate (superspan) recall

  • Consolidation/Storagedefinition: process of making new memories permanentbasis: anatomic and physiological changes at cellular level; hippocampal system importantwhen? during study-test intervalduration: hours? days? years?clinical symptom: delayed memory
  • Retrievaldefinition: process of locating, selecting, and activating a memory representationbasis: re-enactment of pattern of excitation occurring at encodingwhen? at point of testclinical symptom: recall
  • Key PointsExtended memory system including hippocampus, amygdala, and basal forebrainWe (basically) understand anatomy, now we need to understand computationNotion of distinct subtypes of amnesia generally less favorable now than 10 years agoCertain structures are wired for associational processing; these structures are reciprocally connected to cortical processors