The clinical case studies were complemented by animal and human laboratory studies that helped refine these hypotheses and generated rigorous measures linking social cognition to brain function. Studies used techniques such as visual half-field presentations, capitalizing on the projection of each visual field to the contralateral hemisphere (Natale, Gur & Gur, 1983). For example, using chimeric presentations, Sackeim, Gur, & Saucy (1978) found that emotions are expressed more intensely on the left side of the face, and that this effect is specific to negative emotions (Sackeim & Gur, 1978; Indersmitten & Gur 2003). Electrophysiological studies have supported the link between hemispheric functioning and emotion processing (Davidson et al., 2000; Gasbarri et al., 2007). In addition to linking brain function to behavior, such studies have helped generate measures of social cognition and emotion processing that could be applied in the emerging methodology of functional neuroimaging.
