1. Components of the visual system

4. The individual neuron

5. Neuron

6. Neurons Purkinje cells from cerebellum, dendrites showing calcium concentration

7. Synaptic connection

8. Synapse

9. The Eye The main aspects are the photoreceptors, which is the input layer, and the ganglion cells, the output layer to the brain

10. Eye

11. Neural circuitry of the retina

12. Receptors Density - Fovea

13. Photoreceptors

15. Visual receptor types

16. Spectral sensitivity

17. Color Mixing

18. Dynamic Range

19. Center-surround Receptive Fields Modified from PSY280F

20. Edge-detection by zero-crossings Some theory, and the relation to ganglion cells.

22. Edge Detection by Z.C. Peak in f’(x) z.c. in f’’(x) Noise: Asin(wx) > -w 2 cos(wx) Convolve with a Gaussian (optimal) d 2 /dx 2 (G*f) = d 2 /dx 2 (G) * f In 2-D: d 2 /dx 2 + d 2 /dy 2

23. Edge Detection by Z.C.

25. Z.C. at Two Scales

27. Wheel Edges 4 Resolutions

28. LGN Layers

29. The Cortex The main topics are: area V1 in some details, response properties of cells in V1, how they are organized in the area. General properties of higher level visual areas.

30. Physiological Recording

31. Orientation Selectivity

32. V1: Direction selectivity Modified from PSY280F

33. End-stopped cell

34. Simple Cells

38. Visual Areas

39. Bi-directional Computation

42. Stimuli tested in V2, V4

44. From: Tanaka, 1996 Columnar modules of region TE

45. fMRI Magnet

46. fMRI Activation Slice

47. fMRI Activation