Assimilation Theory, Attentive Fields, and the Müller—Lyer Illusion

Perception ◽  
1978 ◽  
Vol 7 (3) ◽  
pp. 297-304 ◽  
Author(s):  
Michael Bross ◽  
Richard Blair ◽  
Paul Longtin
Keyword(s):  
Field Size ◽  
Assimilation Theory ◽  
Unitary Theory ◽  
Attentive Field ◽  
Lyer Illusion

The assimilation theory of geometric illusions was employed to predict changes in the outgoing and ingoing forms of the Müller—Lyer illusions as a function of attentive field size. It was found that the theory predicted correctly the form of the function relating amount of illusion and size of attentive field only for the outgoing Müller—Lyer. For the ingoing illusion the prediction was opposite to the empirically obtained results. The findings are seen as additional evidence for the untenability of a unitary theory, such as assimilation theory, for both versions of the Müller—Lyer illusion as they fail to account for substantial differences between them.

Attention and the Müller-Lyer Illusion: Simulation of an Experiment by Larsen and Garn

1989 ◽  
Vol 68 (3_suppl) ◽  
pp. 1323-1329 ◽  
Author(s):  
Alexander W. Pressey ◽  
Bernd Kersten
Keyword(s):  
Computer Simulation ◽  
Assimilation Theory ◽  
Visual Distortion ◽  
Lyer Illusion ◽  
Separate Effect ◽  
Close Relationship

An assimilation theory of visual distortion which emphasizes the role of attention was used to explain results obtained by Larsen and Garn (1988). A computer simulation of their experiment showed a close relationship ( r = .81) between obtained and predicted patterns of results in Müller-Lyer configurations. It was deemed unnecessary to postulate a separate effect in which fins of Müller-Lyer figures interfere with the ability to make a veridical comparison between shafts.

Effects of Gap Size between Shaft and Fins and of Angle of Fins on the Müller—Lyer illusion

Perception ◽  
1977 ◽  
Vol 6 (4) ◽  
pp. 435-439 ◽  
Author(s):  
Alexander W Pressey ◽  
Vincent Di Lollo ◽  
Robert W Tait
Keyword(s):  
Assimilation Theory ◽  
Gap Size ◽  
Comparison Line ◽  
Lyer Illusion ◽  
Apparent Length

Assimilation theory was employed to generate quantitative predictions relating the ingoing Müller—Lyer illusion to both angle of fin and gap between shaft and fin. Gap sizes were varied from zero to 18 mm in steps of 2 mm, and angles of fins were varied from 30° to 180° in steps of 30°. Five subjects adjusted the length of a comparison line to match the apparent length of the shaft at each combination of gap size and angle of fin. It was predicted that the gap necessary for a reversed illusion to occur, and the gap at which the maximal reversed effect occurred, would be inversely related to angle of fins. Empirical functions verified the predictions.

Influence of Instructions and Cognitive Articulation on Reducing the Müller-Lyer Illusion with a Repeated Trial

1984 ◽  
Vol 59 (3) ◽  
pp. 791-796 ◽  
Author(s):  
Santo Di Nuovo
Keyword(s):  
Female Students ◽  
Assimilation Theory ◽  
Illusory Effect ◽  
Repeated Trial ◽  
Lyer Illusion ◽  
Geometrical Illusions ◽  
Trial Analysis ◽  
Significant Difference

The role of specific, suggestive instructions and of the subject's cognitive articulation in fostering modifications of Müller-Lyer illusory effect was studied. 60 female students were divided into four subgroups on the basis of (a) Witkin's GEFT scores and (b) instructions given to the subjects for the repeated trial. Analysis shows no statistically significant difference between the more and less articulated subjects on the first trial, for influence of both cognitive articulation and instructions or their interaction on the reduction of the illusion. Data are interpreted in terms of some theoretical explanations of geometrical illusions, such as ‘centration theory’ and ‘assimilation theory’.

Evidence for the Role of Attentive Fields in the Perception of Illusions

1974 ◽  
Vol 26 (3) ◽  
pp. 464-471 ◽  
Author(s):  
Alexander W. Pressey
Keyword(s):  
Ponzo Illusion ◽  
Assimilation Theory ◽  
Comparison Line ◽  
Lyer Illusion ◽  
Correct Direction ◽  
Perception Of Illusions

On the basis of the concept of attentive fields, it was predicted that the position of the comparison line would systematically affect the amount of illusion displayed in the Ponzo configuration and in two impoverished forms of the Müller-Lyer illusion. Ten of 12 predictions which seemed to be unique to assimilation theory were verified statistically and the remaining two predictions were in the correct direction. A reversed Ponzo illusion which was expected from the concept of attentive fields was not exhibited. This latter result was explained on the basis of the fact that the Müller-Lyer illusion of elongation is normally greater than the Müller-Lyer illusion of shrinkage.

Assimilation Theory and the Reversed Müller—Lyer Illusion

Perception ◽  
1973 ◽  
Vol 2 (2) ◽  
pp. 211-218 ◽  
Author(s):  
A W Pressey ◽  
M Bross
Keyword(s):  
Assimilation Theory ◽  
Mathematical Formula ◽  
Lyer Illusion

The assimilation theory of geometric illusions was employed to explain the reversed ingoing form of the Müller–Lyer illusion. The mathematical formula which was used previously to predict changes in the Ponzo and Poggendorff illusions was employed in simulated experiments on the reversed Müller–Lyer illusion. It correctly predicted the form of the function, relating illusion to size of gap, that was found previously by Fellows (1967). In addition it correctly predicted the effects of increasing the length of the fins on the form of the function. Finally a reversed outgoing Müller–Lyer illusion was found when the outgoing fins were moved towards the center of the shaft.

Comments on Assimilation Theory and the Reversed Müller—Lyer Illusion

Perception ◽  
1973 ◽  
Vol 2 (2) ◽  
pp. 219-223 ◽  
Author(s):  
B J Fellows
Keyword(s):  
Experimental Work ◽  
Preceding Paper ◽  
Assimilation Theory ◽  
Lyer Illusion ◽  
Recent Experimental Work

This paper is a comment on the preceding paper in this issue by Pressey and Bross. The author reviews his position on the reversed Müller–Lyer illusion in which the illusion is explained in terms of the ‘enclosing nature’ of the ingoing fins. The two difficulties with this explanation pointed out by Pressey and Bross are discussed. Recent experimental work on the effects of enclosures is reported. A critique of Pressey and Bross's explanation of the reversed Müller–Lyer illusion is presented.

Evidence for the Role of Attentive Fields in Masking

Perception ◽  
1980 ◽  
Vol 9 (1) ◽  
pp. 31-36 ◽  
Author(s):  
Alexander W Pressey ◽  
Alexander E Wilson ◽  
Dan W Harper
Keyword(s):  
Visual Illusions ◽  
Assimilation Theory ◽  
Mathematical Formula ◽  
Attentive Field ◽  
Group Functions ◽  
The Individual

A masking task was employed to determine whether predictions derived from the attentive-field postulate of assimilation theory could be verified. The distance between masking and test lines was varied both towards and away from the center of the attentive field. As predicted, masking was greater when the mask was near the center of attention than when it was located at the periphery of the field. A variation of the mathematical formula developed previously to predict visual illusions was employed to fit the individual and group functions found in this study.

Sign in / Sign up

Export Citation Format

Share Document