Visual-Field Differences in Recognition of Male and Female Faces

Variations in the normally observed advantage for facial recognition of stimuli in the left visual field have been observed as a function of changes in stimulus attributes. The present study examined whether the interaction between the sex of the subject and sex of the stimulus face also results in variations in effects of visual field. This possibility was suggested by a number of free-field studies which indicated an interaction between these two factors on the accuracy of facial recognition. 16 volunteers viewed a series of male and female faces presented tachistoscopically to the left and right visual fields. When the sex of the subject and the sex of the stimulus face were the same, superiority for presentation in the left visual field was demonstrated ( p < .05). In addition, although female faces were more difficult to recognize than male faces ( p < .01), this did not influence the visual-field effect. These results were discussed in terms of both the sex-of-face effect and visual-field differences in facial recognition.

Visual Asymmetry on a Color-Naming Task: A Developmental Perspective

5-, 7-, and 10-yr.-old children were tested on a lateralized color-naming task, the colors being presented unilaterally and monocularly. Each age group was composed of 20 boys and 20 girls. A significant effect of age was found, with the greatest perceptual asymmetry (a significant left visual-field effect) being observed for the 5-yr.-old group, and the smallest perceptual asymmetry for the 7-yr.-old group.

Cerebral Asymmetries in Random-Dot Stereopsis: Reversal of Direction with Changes in Dot Size

Visual field differences in stereoscopic form recognition using Julesz-type random dot stereograms were investigated. Dot size was varied in order to test the possibility that variations in the carrier dimension have contributed to past estimates of visual field differences. Twelve male and twelve female subjects, all right-handed, appeared for three test sessions—one with each different dot size. In each session the stimuli were flashed twenty-four times in each visual field, for 120 ms. Results showed no overall visual field effect, but a highly significant interaction between visual field and dot size. For small dots, left visual field superiority was observed, as previously reported by Durnford and Kimura. With large dots, however, the right visual field was superior. This reversal of visual field differences as a function of dot size implies that there is no consistent cerebral hemispheric specialization for stereopsis or stereoscopic form recognition per se. Instead, it appears that there is relative hemispheric specialization for responding to the carrier of stereoscopic information.

The Components of the Standard and Reverse Müller-Lyer Illusions

The absolute contribution of each type of oblique figure in the standard and reverse Müller-Lyer illusions is determined by placing one oblique figure at different distances from the end of a test line (either horizontal or vertical) and measuring shift in the line's apparent midpoint as a function of proximity of the oblique figure. The absolute effect of both types of figure, apex-in > < or apex-out < > is one of contraction, and superimposed on this, again for both types of figure, is a smaller expansion effect which is phasic and varies with proximity of the figure to the line. The major factor in the reverse illusion appears to be the apex-in > < and not the apex-out < > figure as previously supposed. For both standard and reverse illusions, and again for both types of figures, there is a visual field effect, since contraction is greater when the obliques lie in the right or in the lower hemifield. The fundamental similarities in mode of action of each type of oblique are further demonstrated by showing that geometrical figures in general, regardless of shape or orientation, give rise to similar patterns of absolute contraction with a phasic expansion component superimposed. The Müller-Lyer oblique figures therefore operate as two of many possible examples of a single underlying mechanism, and recent arguments that the Müller-Lyer is really two separate constituent illusions are not supported.