1. Vision

2. 2 Brodmann Original

3. 18 19 Calcarine 17

4. Collateral Sulcus 18 19 17 37 Fusiform Gyrus 18

5. 5 Visual System - Medial Structures

6. Visual system

9. fMRI of the Visual System Functional anatomy  V1-V4  MT and Dorsal Stream  LO, IT, & Ventral Stream E.g.’s of Functional characterization  Contours in V1-> LO  Organization in LO & IT

10. Retinotopy: Background

11. 11

12. 12 Tootell - Foveal Magnification

13. Retinotopy: Stimulus

14. Retinotopy: Results in V1 Slice

15. Retinotopy: Unfolded results

18. ©2011 Mark Cohen, all rights reservedwww.brainmapping.org 18 Response Latency vs. Stimulus Duration Average of 10 recordings 100 ms 17 ms 1 sec -5051015 Stimulus sec Data courtesy of Robert Savoy

19. Cohen Contrast Response Test From R. Tootell 060120180240300360 Time (seconds) 1.6% 6.3% 25%78% 82% MT V1

21. Mendola et al.: Approach ID areas w/retinotopy and flattening Measure response to different kinds of contours. Compare patterns of responses across contours and across areas

24. EG Corbetta et al

29. Selective attention to shape, color, motion Attend Shape Attend Color Attend Speed

30. Color 19 near 37 Achromatopsia

31. 19/39 MT V5 akinetopsia

32. Cohen 09/28/11 Calculating Images 060120180240300360 Time (seconds) 1.6% 6.3% 25%78% 82% MT V1 060120180240300360 Time (seconds) Moving Stationary Moving Stationary From R. Tootell V1 MT Dissociation of Contrast and Motion

33. 39/19

34. Cohen 09/28/11 Calculating Images Enigma Isia Levant

35. Cohen 09/28/11 Calculating Images Superior Colliculus

36. Cohen 09/28/11 Calculating Images Motion After Effect Time (s) -24-1201224 Culham, et al., J Neurophysiol 81: 388-393, 1999

37. Cohen 09/28/11 Calculating Images Area ‘ LO ’ Grill-Spector, et al., Human Brain Mapping 6:316–328(1998) Rafael Malach

38. Object presentation Fusiform- 37

39. Levy et al.: Intro  Background: Subdivisions of ventral cortex  LO, FFA, PPA, Chairs, Tools  Q: Is there any organization to this?  A: Look at center/periphery retinotopy

40. Levy et al.: Methods  Stimuli: Faces, houses; center, periphery  Block design, each type alternated with blank  Blocks randomly ordered  Correlation analysis

41. Objects Places Within category Within category

42. Spatial Frequency and Laterality

43. Disorders of visual perception 1.Scotoma- loss in retinotopic representation V1-2 2.Achromatopsia V4 lesion 3.Akinetopsia V5 lesion 4.Agnosia 5.Object agnosia 6.Prosopanosia 7.Letter agnosia/pure alexia 8.Anomia vs agnosia?

44. Agnosia: a loss of ability to recognize objects, persons, sounds, shapes, or smells while the specific sense is not defective nor is there any significant memory loss. Apperceptive agnosia: -unable to distinguish visual shapes and - have trouble recognizing, copying, or discriminating between different visual stimuli. - unable to copy images Associative agnosia: -Inability to recognize objects; -retain semantic knowledge; -can describe visual info, can copy

45. Prosopagnosia: Inability to recognize or discriminate faces Found in RH or bilateral lesions Lateral Fusiform: FFA lesions Integrative agnosia or Simultanagnosia: can recognize 1 element at a time, cannot Process more than 1 element or integrate elements into a whole percept (Hooper) -bilateral P-O junction (blind to objects outside of central focus) -left ventral T-O junction (sequential recognition)

46. Higher level vision- “ what ” system V2 secondary vision; stereopsis V3 form V4 color, color/shape V5 motion- towards the where; shape from motion

47. Higher level vision: what vs where

48. The transition to spatial vision: parietal lobe Parietal lobe disorders Neglect syndromes: body and space Working memory: sustained “ where ” processing Apraxic disorders constructional apraxias ideational (pretend you have a hammer in your hand- show me how you use it) Sequencing deficits

49. Cohen 09/28/11 Calculating Images States Task Arizona California Oregon Washington Idaho Montana N. Dakota Minnesota (with Richard DuBois)

50. Cohen 09/28/11 UCLA Brain Mapping Center Calculating Images Group Result - Geographic Imagery LR BA 18/19, V1+ BA19 BA 19 (+39?) MT BA18 (V2) z ≥ 4z ≤ 2.5 (with Richard DuBois)

51. Field cut vs. neglect?

52. Laterality and visual deficits Spatial frequency Gestalt vs detail processing Tests that emphasize lateralized visual differences –Block design-qualitative analysis

54. 40 39 7 IPS

55. 40 39 7