1. INTRODUCTION Bilateral Electrodermal Responses to Lateralized Stimuli Presentations McGinley, J.J., Magruder, K., Morrill, A.R., Worthen, J., Yang, X., Klineburger, P. C. & Friedman, Bruce.H. Correspondence to: jaredmc@vt.edu Presented at the 24 th annual conference for the Association of Psychological Science (APS) May 27th, 2012, Chicago, Il. Subjects: 73 Right-handed undergraduate students (37 female) Tasks Subjects submerged each foot in ice water (~10°C) up to the ankle. Both tasks were three minutes in duration. Both submersion periods were preceded by a three minute baseline period, and followed by a three minute recovery period. Physiological Measurements: Skin Conductance (SCR) CONCLUSION/LIMITATIONS RESULTS CURRENT STUDY DISCUSSION Bilateral skin conductance garnered much attention in psychophysiological research during the 1970s and early 1980s. General findings indicate large differences between right and left hand reactivity (Hugdahl, 1984) with the occasional findings indicating electrodermal responses as generally being equal between the right and left hand (Erwin, McClanahan, & Kleinman, 1980). A larger question that also remains unclear is the lateralized regulation of these electrodermal responses. While Holloway & Parsons (1969) originally suggested that this activation is regulated by the contralateral hemisphere, recently, Rosalind Picard has suggested that the regulation is ipsilateral (2011). To even further complicate the matter, Boucsein (1991) has suggested that EDA can be differentially regulated by each hemisphere depending on the context of the situation used to induce reactivity. These results suggest a larger role of the right hemisphere in regulating EDA. These findings have implications for existing laterality models in regulating autonomic nervous system activity. Although a lively debate still exists, it has generally been accepted that the right hemisphere serves the dominant role in regulating activity of the sympathetic nervous system (Craig, 2005), while the parasympathetic nervous system is either regulated primarily by the left or the right hemisphere (Thayer & Lane, 2009; Foster & Harrison, 2005). Since the literature is clear for indicating that the right hemisphere serves a larger regulatory role in regulating sympathetic activity, and that SCR is almost solely due to sympathetic activity, then it should be assumed that the hand that produces the larger SCR should correspond with right hemisphere regulation. The results tentatively implicate contralateral hemispheric regulation of electrodermal responses. Additional subjects will contribute to a more informed discussion with greater theoretical implications. The cold pressor task has typically been used to assess hemodynamic responses. Therefore, a lateralized task that has reliably been shown to elicit SC activity may more appropriately address the question at hand. MeanSDF-valuedfp-valuePartial Eta Sq. SCR Right Hand CPrt0.060.1118.071640.00010.22 CPlft0.090.1142.699620.00010.408 SCR Left Hand CPrt0.070.1321.429640.00010.251 CPlft0.10.1244.86620.00010.42 HandTaskMeanSDF-valuedfp-valuePartial Eta Sq. SCR Right HandCP (L-R)0.030.115.273620.0250.078 SCR Left HandCP (L-R)0.0250.1043.724620.0580.057 MeanSDF-valuedfp-valuePartial Eta Sq. CPrtL-R0.0130.0553.385640.070.05 CPlftL-R0.0060.0610.603620.4410.01 Between Hand Within Task Within Hand Between Task Reactivity to Task