Perception Lab Louise Delicato



Plaid Stimuli

Plaid stimuli (chessboard pattern) are created by superimposing two differently oriented gratings (stripey patterns).  This movie shows two differently oriented gratings presented in circular apertures that partially overlap.  The plaid pattern occurs in the region in which they overlap. 

An important property of plaid stimuli is that the plaid pattern moves in a direction that is different to that of the component grating motions - in this example the plaid pattern moves directly upwards while the gratings move upwards and to the right and upwards and to the left.

Other examples of stimuli used in visual psychophysical experiments can be found here.