COGNITIVE NEUROSCIENCE AND NEUROPSYCHOLOGYThe late positive potential and explicit versus implicit processing of facial valenceVan Strien, Jan W.a; De Sonneville, Leo M.J.b; Franken, Ingmar H.A.aAuthor Information aErasmus Affective Neuroscience Lab, Institute of Psychology, Erasmus University, Rotterdam bDepartment of Clinical Child and Adolescent Studies, Faculty of Social Sciences, Leiden University, Leiden, The Netherlands Correspondence to Dr Jan W. Van Strien, PhD, Institute of Psychology, Erasmus University Rotterdam, PO Box 1738, 3000 DR Rotterdam, The Netherlands Tel: +31 10 4088787; fax: +31 10 4089009; e-mail: firstname.lastname@example.org Received 11 January 2010 accepted 7 April 2010 NeuroReport: June 23rd, 2010 - Volume 21 - Issue 9 - p 656-661 doi: 10.1097/WNR.0b013e32833ab89e Buy Metrics Abstract The late positive potential (LPP) depicts brain electrical activity during both automatic and controlled sustained attentional processing of emotional stimuli. We investigated in a sample of 18 healthy women how the LPP is modulated by facial expression during an explicit valence rating task and an implicit sex classification task. Midline LPP amplitudes were significantly larger for valence rating than for sex classification. During valence rating, faces with a positive valence resulted in larger LPP amplitudes at centrofrontal electrodes than faces with a negative valence. During sex classification, a similar valence effect was observed at midline parietal electrodes. This implicit LPP valence effect appears to depend on higher visual processing, as during an additional sex classification task with blurred faces no such implicit valence effect was found. © 2010 Lippincott Williams & Wilkins, Inc.