態度雙歧性是指態度同時具有正向與負向評價的程度。過去有研究指出認知需求或議題涉入程度愈高則態度雙歧性愈低；態度雙歧性愈高者愈可能對相關訊息探用系統性處理。此論文以兩個研究來探討系統性訊息處理與態度雙歧性的關係。研究一以相關法測量參與者對社會議題的態度雙歧性、認知需求及涉入程度，結果顯示認知需求與涉入程度分別與態度雙歧性呈現負相關。研究二使用實驗法，以兼具正負向評價之社會事物為態度對象，操弄個體的認知負荷高低與判斷對象是個人或團體，並測量參與者的認知需求。結果顯示對個人的態度雙歧性高於對團體，高認知需求者形成的態度雙歧性較高，低認知需求者則在高認知負荷之下，對於團體對象的態度雙歧性較低。此結果展現系統性訊息處理與態度雙歧性有正向關連。本研究結果指出就既有社會議題的態度而言，提升系統性訊息處理的性格與動機因素與態度雙歧性呈負向關係，但形成新態度時探用系統性處理訊息則可能提高態度雙歧性。

Attitudinal ambivalence refers to the extent to which individuals' attitudes toward an attitude object include both positive and negative evaluations. Some research suggests that higher need for cognition and greater involvement with social issue, are associated respectively with less attitudinal ambivalence. Other research suggests that individuals with ambivalent attitudes are more likely to engage in systematic processing of relevant information. To explore the relation between systematic information processing and ambivalent attitudes, Study 1 used a correlational strategy to assess participants’ need for cognition, attitudinal ambivalence toward five social issues, and the degree of involvement in the issues. Results replicated prior findings of a negative relation not only between attitudinal ambivalence and need for cognition, but also between attitudinal ambivalence and issue involvement. In Study 2, participants were provided with positive and negative mixed-valence information about a social target. The entitativity of attitude objects (individual vs. group) and the levels of cognitive load were manipulated, and participants’ need for cognition was assessed. Results showed higher attitudinal ambivalence for the individual than the group target. Participants high in need for cognition had high attitudinal ambivalence regardless of the attitude objects and the levels of cognitive load, those low in need for cognition had lower attitudinal ambivalence toward the group than the individual target when they were under high cognitive load. The results of Study 2 suggested an influence of systematic processing on the formation of ambivalent attitudes. These results suggest that, for well-established attitudes, attitudinal ambivalence relates negatively to personality-based and motivational antecedents of systematic processing, whereas systematic processing of positive and negative mixed-valence information about a new attitude object can result in high attitudinal ambivalence.