The predominant view of hemispheric contributions to emotional ity focuses upon the inherent emotionality of the right hemisphere, in contrast to the logical, rational, nonemotional characteristics of the left hemisphere. However, recent research has also implicated contri butions of the left hemisphere during affective arousal (d\u27Elia & Perris, 1973, 1974; Ehrlichman & Wiener, Notes 10, 11; Harman & Ray, 1977; Tucker, Antes, Stenslie & Barnhardt, 1978; Tucker, Roth & Shearer, Note 7). Some reports have implicated the left hemisphere in negative affect (Ehrlichman & Wiener, Notes 10, 11; Harman & Ray, 1977), and the right hemisphere in positive affect (Ehrlichman & Wiener, Notes 10, 11). Others have suggested interactional conceptualizations of hemispheric contributions to emotionality (e.g., Bakan, Note 5; Galin, 1974, 1977; Tucker, Note 12), for which tentative empirical support has been reported (Tucker, Antes, Stenslie & Barnhardt, 1978; Tucker, Roth & Shearer, Note 7). From an interactional viewpoint, a given hemisphere is neither inherently rational or emotional, nor inherently positive or negative: subjective emotion is a result of the interaction between the primitive, spontaneous right hemisphere and the inhibiting, constricting left hemisphere.
The present study sought to lend direction to further theorizing about the role of the cerebral hemispheres in emotionality through vary ing both the positive vs. negative dimension of the affective state, and the inhibitory vs. facilitative orientation with which the individual approaches affective arousal. Sexual arousal and aversive arousal were chosen as prototypic examples of affective arousal with positive and negative valences, respectively. Prescreened sexual and aversive slides were shown individually to 48 Introductory Psychology students (24 males, 24 females), under instructions to either facilitate or inhibit arousal. During each of the four counterbalanced, within-subjects con ditions (i.e., positive-inhibit, positive-facilitate, negative-inhibit, negative-facilitate), relative hemispheric activation was assessed via an index of auditory attentional bias (Kinsbourne, 1970; Tucker, Antes, Stenslie & Barnhardt, 1978).
No direct indication of differential hemispheric involvement, as evidenced by mean attentional bias across conditions, was observed for the grouped data; a slight right bias was evident across conditions. Prediction of attentional bias using subject involvement ratings sug gested that both success in generating aversive arousal and lack of suc cess in inhibiting aversive arousal were accompanied by relatively greater right hemisphere involvement. However, greater right hemisphere activation was characterized by less physical arousal, thus emphasizing the heterogeneous nature of aversive arousal. Trait Anxiety Inventory, Sex-Guilt Inventory, and Stroop Color-Word Test scores were not effec tive predictors of attentional bias.
Under instructions to facilitate arousal, subjects tended to report cognition characterized by imagery, global perception of the slides, and absence of internal verbal dialogue. Under instructions to inhibit arousal, subjects tended to report cognition characterized by internal verbal dialogue, analytic perception of the slides, and absence of imagery. Parallels were drawn between the differential cognitive strategies reported by subjects across the facilitation vs. inhibition dimension, and the differential processing characteristics of the cere bral hemispheres. These categorical data suggest relatively greater right hemisphere involvement during facilitation of arousal and rela tively greater left hemisphere involvement during inhibition of arousal, across both positive and negative affect. This result was not corrobo rated by attentional bias data; possible difficulties with the atten- tional bias paradigm are discussed.
The attentional bias data do not support earlier reports that the left hemisphere is characterized by negative affect (Ehrlichman & Wiener, Notes 10, 11; Harman & Ray, 1977), while the right hemisphere is characterized by positive affect (Ehrlichman & Wiener, Notes 10, 11). In the present study, the facilitation of aversive arousal was character ized by less left and more right hemispheric involvement, while the results for sexual arousal were insignificant. Categorical analyses of subjects\u27 descriptions of their experience provide tentative support for a model of hemispheric contributions to emotionality which focuses upon the interaction between an inhibiting, constricting left hemisphere and a primitive, spontaneous right hemisphere. Implications for future research, psychopathology, and psychotherapy are discussed