The latest works 32
since April 14, 2008
"Tanuki"
A fat tanuki appears to be shorter in height than a slim one.
Copyright Akiyoshi Kitaoka 2008 (June 15)
"Moving chopsticks"
Vertically standing chopsticks appear to tilt and move laterally.
Copyright Akiyoshi Kitaoka 2008 (June 16)
"Crashes"
Crosses appear to scintillate.
Copyright Akiyoshi Kitaoka 2008 (June 6)
"Pink hearts and orange hearts"
The upper-left heart and lower-right hearts appear to be yellowish and the rest appear to be bluish-white, while they are the same white as the background. The afterimages of the former are pink hearts and those of the latter are orange hearts. Watch the left cross more than ten seconds and move the gaze to the right cross, the illusory pink and orange hearts appear for a short period.
Copyright Akiyoshi Kitaoka 2008 (May 25)
"BCG"
Copyright Akiyoshi Kitaoka 2008 (May 13)
This image consists of only cyan (greenish blue) with a variety of levels
of saturation, but there appear eighteen red patches. This image is a GIF
file of 8 bit color with a palette of 256 different colors, as shown below.
Although lower rows in the palette appear to be tinted reddish, they all
are cyan (with low saturation).
Moreover, the negative afterimage of this illusory red is cyan!! This illusory cyan appears earlier than the surrounding illusory red (=
the afterimage of the background cyan).
Another image
"The nine color patches"
Copyright Akiyoshi Kitaoka 2008 (May 13)
The nine patches in the left half appear to be slightly reddish, but they
are the same color as the nine patches in the right half (R170, G220, B220).
Moreover, the negative afterimage of this illusory red is cyan (!), while the right patches give red afterimages naturally. This discrepancy suggests that (part of ) negative afterimages should depend on perceived color, not on 'physical' color.
Fix your eyes on either of the crosses for more than ten seconds, and move
your gaze to the other cross. Then, negative afterimages appear.
"Planet of the Snakes"
"Planets" appear to rotate.
Copyright Akiyoshi Kitaoka 2008 (January 20; uploaded May 10)
"Corridor illusion in an antigravity hill image"
The left person is the same size of the right one, but the latter appears to be larger than the former. In particular, the cast shadow of the right person appears to be much larger than that of the left, though they are the same size. This is a variant of the corridor illusion.
Copyright Akiyoshi Kitaoka 2008 (May 8)
Antigravity hill illusion in Japan
corridor illusion:
Bezold, W. von (1884) Eine perspektivische Täuschung. Annalen der Physik und Chemie, 123, 351-352.
Luckiesh, M. (1922) Visual illusions. New York: Dover.
Richards, W. and Miller, J. F. Jr. (1971) The corridor illusion. Perception & Psychophysics, 9, 421-423.
<corrected January 9, 2012: corrider -> corridor>
"Red roof"
The left red roof appears to be slimmer than the right one, though they are the same in size and shape. This illusion is probably a variant of the Shepard illusion.
Copyright Akiyoshi Kitaoka 2008 (April 21)
Shepard illusion or table-top illusion:
Shepard, R. N. (1990) Mind sights: original visual illusions, ambiguities, and other anomalies, with a commentary on the play of mind in perception and art. New York: Freeman.
"Three staircase illusions"
This picture contains at least three illusions. (1) The left staircase appears to head slightly leftward, the middle one appears to go in the middle direction, while the right staircase appears to head slightly rightward. This illusion is a variant of the Leaning Tower illusion (Kingdom et al., 2007). (2) In each staircase, lower steps appear to tilt leftward while the upper ones rightward. This illusion is called the skewed staircase illusion by S. Tsuinashi. (3) Each staircase appears to ascend, though this effect is weak.
Copyright Akiyoshi Kitaoka 2008 (April 21)
References
Kingdom F A A, Yoonessi A, Gheorghiu E, 2007, "The Leaning Tower illusion: a new illusion of perspective" Perception 36(3) 475-477
"Girl-shrinking illusion"
The middle girl appears to shrink though they are of the same size.
Copyright Akiyoshi Kitaoka 2008 (April 14)
This illusion is called the (Kanizsa) amodal shrinkage.
References
Kanizsa, G. (1972) Schrumpfung von visuellen Feldern bei amodaler Ergänzung. Studia Psychologica, 14, 208-210.
Kanizsa, G. (1975) Amodal completion and phenomenal shrinkage of surfaces in the visual field. Italian Journal of Psychology, 2, 187-195.
Kanizsa, G. (1979) Organization in Vision. New York: Praeger.
Vezzani, S. (1999) Shrinkage and expansion by amodal completion: a critical
review. Perception, 28, 935-947.
Mitsudo, H. and Nakamizo, S. (2005) Evidence for the correcting-mechanism
explanation of the Kanizsa amodal shrinkage. Perception, 34, 289-303.
Vezzani (1999) reviewed the Italian studies on the shrinkage illusion (and the expansion illusion) and showed that this illusion does not depend on amodal completion. According to his review, I do not think that the name "Kanizsa amodal shrinkage" is good; instead, "Kanizsa shrinkage illusion" might be better, for example.
Copyright Akiyoshi Kitaoka 2008 (April 21)
31 The latest works (March 2008 - March 2008)
30 The latest works (January 2008 - March 2008)
29 The latest works (December 2007 - January 2008)
28 The latest works (October 2007 - December 2007)
27 The latest works (August 2007 - September 2007)
26 The latest works (June 2007 - August 2007)
25 The latest works (March 2007 - June 2007)
24 The latest works (March 2007 - March 2007)
23 The latest works (February 2007 - March 2007)
22 The latest works (December 2006 - January 2007
21 The latest works (October 2006 - November 2006)
20 The latest works (August 2006 - October 2006)
19 The latest works (July 2006 - August 2006)
18 The latest works (June 2006 - July 2006)
17 The latest works (May 2006 - June 2006)
16 The latest works (May 2006 - May 2006)
15 The latest works (April 2006 - May 2006)
14 The latest works (March 2006 - April 2006)
13 The latest works (March 2006 - March 2006)
12 The latest works (February 2006 - February 2006)
11 The latest works (February 2006 - February 2006)
10 The latest works (January 2006 - February 2006)
9 The latest works (November 2005 - December 2005)
8 The latest works (October 2005 - October 2005)
7 The latest works (September 2005 - October 2005)
6 The latest works (June 2005 - August 2005)
5 The latest works (April 2005 - June 2005)
4 The latest works (March 2005 - April 2005)
3 The latest works (June 2004 - March 2005)
2 The latest works (April 2004 - June 2004)
1 The latest works (August 2003 - May 2004)
0 The latest works (June 2002 - July 2003)