Our results are also in line with many studies that show gender differences in the degree of lateralization of cognitive and affective processes. Considerable data support greater hemispheric lateralization in men than women for linguistic tasks [33] and for spatial tasks [34]. Gender differences have also been found in the lateralization of visual-spatial processes such as mental rotation [35] and object construction tasks [36], in which males are typically right hemisphere (RH) dominant and females bilaterally distributed. More relevant to the present experiment are the data provided by Bourne [37], who examined the lateralization of processing positive facial emotion in a group of 276 right-handed individuals (138 males, 138 females). Subjects were asked to observe a series of chimeric faces formed with one half showing a neutral expression and the other half showing a positive expression in the left or right visual field, and to decide which face they thought looked happier. The results showed that males were more strongly lateralized than women in the perception of facial expressions, showing a stronger perceptual asymmetry in favour of the left visual
