1. PSYCH 2220
Perception
Lecture 5

2. Keywords for lecture 4
Lateral geniculate nucleus, layers, magnocellular, parvocellular, magnification factor, simple cells, complex cells, hypercomplex cells, Hubel and Wiesel
cortical cells tuned for orientation, binocular, tuned for width-of-bars, movement, direction,
tilt after effect, adaptation, channel coding

5. Response before adaptation for each channel...
.. Is reduced depending on each channel’s adaptation.
The peak of the extrapolated curve…
.. Is thus shifted.
Hypothetical
channels
Amount of
adaptation

6. Response before adaptation for each channel...
.. Is reduced depending on each channel’s adaptation.
The peak of the extrapolated curve…
.. Is thus shifted.
Hypothetical
channels
Amount of
adaptation

7. Response before adaptation for each channel...
.. Is reduced depending on each channel’s adaptation.
The peak of the extrapolated curve…
.. Is thus shifted.
Hypothetical
channels
Amount of
adaptation

8. Structure and organization of the cortex

11. Pinwheels in the cortex

12. Visualizing orientation columns in the cortex
(Using radioactive deoxyglucose)

13. Ocular dominance bands over the cortex

15. What happens beyond the hypercomplex cells?
Grandmother cells
heirarchy
prosopagnosia
face cells; hand cells
anatomy

17. transient cells
magnocellular layers of LGN
parvocellular layers of LGN
sustained cells

18. ...from a cell in the Inferotemporal cortex
Stimuli used to investigate processing of
cells in the inferotemporal region. The image of the monkey’s hand elicited the largest response….
...from a cell in the Inferotemporal cortex

19. ...from the Inferotemporal cortex
A face cell….
...from the Inferotemporal cortex

25. An example of distributed coding

28. SPATIAL VISION

29. Fourier’s theorem:
“any complex curve can be mathematical described as the sum of a series of sine waves”

34. Just low frequencies
all frequencies

39. invisible
Threshold contrast
visible
Spatial Frequency

40. Photopic
Threshold contrast
Scotopic
Spatial Frequency