Sex differences in cerebral laterality have been documented in the neuropsychological literature for decades . Across a number of studies, a consistent pattern of [email protected] lateralization of function has emerged, with males typically demonstrating greater lateralization of language and visuospatial abilities, whereas females tend to be less ateralized, showing a greater frequency of bilateral representation of verbal abilities across the two hemi- 0959-4965 & Lippincott Williams & Wilkins spheres .
The sexually dimorphic structure of the nervous system appears to produce consistent asymmetries in affective function, such as the lateralized perception of the affective features of facial expressions of emotion [8?±10], and recent studies have suggested that males may also demonstrate a greater extent of lateralization of emotional perception than females [9,10].
At the cortical level, emotional processing is associated ith consistent patterns of lateralized activity as measured by EEG methods, with positive affect or approach-related emotions associated with relatively greater left than right prefrontal activation, and negative affect or withdrawalrelated emotions associated with the opposite pattern . While lateralization of cognitive abilities is often observed within the neocortex, the extent of functional lateralization within subcortical structures is uncertain.
There is some evidence of a lateralized pattern of amygdala activity during affective processing, with several studies Onding reater left than right amygdala activation during negative emotional facial expressions such as fear [1 2], and sex differences in this lateralized activity may be evident as early as adolescence . In contrast to negative emotions, there have been few studies examining the tunctional responsiveness of the amygdala to positive emotions such as happiness.