Lecture 6: Orientation

1
Lecture 6 Orientation spatial frequency
adaptation -- aftereffects and contrasts
2
The McCollough Effect - orientation contingent
color aftereffect
3
(No Transcript)
4
(No Transcript)
5
Orientation selective and nonselective V1 cells
Tuning curve and corresponding polar plot from 2
macaque V1 cells (one orientation selective, the
other nonselective) in response to drifting bars
of varied orientation and direction.
OBorientation bias. DBdirection bias
6
(No Transcript)
7
(No Transcript)
8
(No Transcript)
9
(No Transcript)
10
Ocular and orientation columns
11
(No Transcript)
12
(No Transcript)
13
(No Transcript)
14
MacKay effect
15
(No Transcript)
16
(No Transcript)
17
(No Transcript)
18
(No Transcript)
19
(No Transcript)
20
(No Transcript)
21
(No Transcript)
22
(No Transcript)
23
(No Transcript)
24
Orientation processing Action without perception?
Milner Goodale, 1993
25
(No Transcript)
26
(No Transcript)
27
(No Transcript)
28
(No Transcript)
29
A
V
P
D
C
H
U
R
Y
A
A
L
X
K
B
M
E
D
N
S
H
F
P
F
E
H
T
30
Attentional Resolution (Shown by Crowding)
A
V
P
D
C
H
U
R
Y
A
A
L
X
K
B
M
E
D
N
S
H
F
P
F
E
H
T
31
(No Transcript)
32
(No Transcript)
33
Not Aware
Aware
34
Adapt
Test
35
Adaptation Results
8
7
6
5
Contrast threshold elevation (adapted / baseline)
4
.
3
2
1
same
same
diff.
diff.
crowded
single
36
(No Transcript)
37
(No Transcript)
38
(No Transcript)
39
(No Transcript)
40
The Zollner Illusion the horizontal lines are
parallel but appear to converge and diverge
41
Questions Neural stage(s) for orientation
adaptation? Does it require awareness of the
adapting orientation?