Figure 1.
To perceive the illusory gray rectangle in the absence of luminance edges defining its control, the openings of the four white inducers must be specular (left) and form the corners of the illusory rectangle. The figure shows an example of a thin Kanizsa illusory rectangle formed by inducer openings with acute angles. Only the global grouping of the four inducers creates the illusion. As a matter of fact, when the same four inducers are all oriented in the same direction, the illusory shape is not perceived (right).
Figure 2.
Discrimination of illusory rectangle.
Psychometric functions are fit to the probability of discriminating whether the Kanizsa illusory rectangle was thin or fat as a function of the deviation of openings' angles from 90 deg and plotted separately for each JMD subject and his or her two age-matched controls.
Figure 3.
Discrimination of four inducers angle.
Psychometric functions are fit to the probability of discriminating whether the openings of the four inducers simultaneously presented were acute or obtuse, as a function of the deviation of openings' angles from 90 deg and plotted separately for each JMD subject and his or her two age-matched controls.
Figure 4.
Discrimination of one inducer angle.
Psychometric functions are fit to the probability of discriminating whether the opening of one of the four inducers randomly presented was acute or obtuse as a function of the deviation of openings' angles from 90 deg and plotted separately for each JMD subject and his or her two age-matched controls.
Table 1.
Patients' characteristics.
Figure 5.
Schematic of visual fields in the right and left eyes of each JMD participant, showing the large extent of the blind field (macular lesion). Black line delimits the damaged area (scotoma).
Figure 6.
Contrast sensitivity curves of the right and left eyes are measured for spatial frequencies ranging between 0.5 to 60 cycles × degree (cpd). The curves of each JMD participant (filled symbols) are compared with the average contrast sensitivity of the six controls (empty symbols). Error bars indicate SD for the control data.