Cognitive architecture is any particular set of processes

הגדרות גישות ומודלים Cognitive architecture is any particular set of processes and the serial or parallel interactions among them. Neural architecture relates to how a particular cognitive architecture is implemented in the brain by neural dynamics in distributed cortical areas, subareas, and neural populations. : מהמבנה לתפקוד ת נא י ה כ (The lesion-deficit approach) מוחי הסקה על תפקוד על בסיס נזק רחי ת נאי 2 : מהתפקוד למבנה מ ס (Functional Imaging ) דימות תפקודית פ י ק

Recovery from aphasia by shift of function? Single subject, stem completion task 13 Bucnker et al. , PNAS, 1996 סוף

Group studies 3 patients with Broca’s aphasia 15 10 patients with neglect

Limb Apraxia Apraxic Pre-rolandic Post-rolandic Pre- & Post. Rolandic 16 Non-Apraxic

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Probabilistic methods החשיבות של אזור )באנטומיה גסה( לתפקוד היא הסתברותית – לא דיכוטומית VLSM fluency auditory comprehension 19 Bates et al. , 2003 חזרה

Mass effect 22 חזרה

Structural scans 29

Static Magnetic Field (B 0) 0. 5 Gauss שדה מגנטי של כדור הארץ 30

T 1 image 33 CSF – Dark Bone – Dark White matter – white Gray matter – Gray Fat – Bright Infarct/Tumor – Dark MS plaque - Dark Blood - Bright Good for structure

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T 2 Image Infarct Tumor 35 CSF – Bright Bone – Dark White matter – Gray Fat – Dark Infarct/tumor – bright MS plaque - bright Good for lesions

השוואה - שיטת דימות מבני שונות Acute CT DWI 37 Angio-CT ADC Angio-CT PWI MRI T 2 FSE Follow up CT חזרה

Post-infarct Brain Edema Midline shift Sulci abolished Pressure on neighboring structures CT 5 days post- stroke 39

Ischemic penumbra Penumbra (“stunned” but viable) 40 Core חזרה

Semantic Dementia Illustration of tasks performed by subjects during scanning Mummery, C. J. et al. Brain 1999 122: 61 -73; doi: 10. 1093/brain/122. 1. 61 42 Copyright restrictions may apply.

Regions of significant regional cerebral blood flow change common both to patients and normals for the main effect of semantic judgements minus visual judgements Mummery, C. J. et al. Brain 1999 122: 61 -73; doi: 10. 1093/brain/122. 1. 61 Copyright restrictions may apply. 43

Differential activation for patients and controls in the contrast of semantic minus visual judgements for both modalities: (A) regions showing significantly reduced regional cerebral blood flow changes for patients relative to controls; (B) regions showing significantly increased regional cerebral blood flow changes for patients relative to controls Reduced in Patients (no structural difference) Enhanced in Patients Atrophy Mummery, C. J. et al. Brain 1999 122: 61 -73; doi: 10. 1093/brain/122. 1. 61 Copyright restrictions may apply. 44

Effect of left frontal damage on reading architecture Price et al. , 2001 Words > Consonants 45

Dynamic diaschisis Reading task 46 Semantic task חזרה

Vascular Territories MCA ACA PCA 47 חזרה

Taking ‘criticality’ seriously Neglect 48 No Neglect Subtraction

Talairach’s normalization frame 50 חזרה

“Equivalent dipole” + + + + -- + - Equivalent Dipole 52 Thalamo-Cortical fiber

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Event Related (“evoked”) Potentials EEG Stimuli: Segmentation Averaging 4 3 2 1 0 -1 -2 -3 55 -100 0 100 200 300 400 500

Effect of frontal lesions on top-down control 56

Whole head MEG 58

Electrical Source Localization The inverse solution is INTRACTABLE in principle 60

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62 W. W. Norton

Equivalent Dipole Localization 63

(2)(3) The Altered damaged electrical area may conduction modulate in the activity damaged of tissue an electrical may diminish source or distant augment fromthe (1) Direct damage to the electrical source generating the ERP lesion; amplitude of scalp-recorded potentials 64

Subdural Grids 65

Visually Selective Neurons in enthorinal cortex 67

Epicorticography (ECo. G) 68

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PET/SPECT Positron Emission Tomography and Single Photon Emission Computerized Tomography (SPET/SPECT) are a type of CT scan. –Standard CTs: transmission of Xrays l. Measure Xray transparency of material between xray tube and detector –PET/SPECT looks at emission of radioactive material. l. E. G. Radioactive oxygen isotope injected into blood l. Brain regions that use oxygen emit more positrons 71 חזרה