Cognitive Neuroscience and Neuropsychology: PDF OnlyBrain potential signs of feature processing during auditory selective attentionWoods, David L.; Alho, Kimmo1; Algazi, AlainAuthor Information Clinical Neurophysiology Laboratory, Dept. of Neurology, UC Davis, VA Medical Center, 150 Muir Road, Martinez, CA 94553, USA 1Dept. of Psychology, University of Helsinki, Finland NeuroReport: April 1991 - Volume 2 - Issue 4 - p 189-192 Buy Abstract WE recorded event-related brain potentials (ERPs) to random dichotlc tone sequences as subjects attended to tone bursts of a designated pitch (250, 1000 or 4000 Hz) and ear of delivery. The effects of attention were isolated as negative difference (Nd) waves by subtracting ERPs to ignored tones from ERPs to the same tones when either one or both features were attended. Early sensory components of the ERP changed tonotopically in scalp distribution, while the distributions of Nd waves were feature-specific (pitch processing differed from location processing) but not tonotopic. At longer latencies, Nd waves specific to feature-conjunction operations were isolated. These began 40–50 ms after Nds to isolated cues and continued for hundreds of ms. © Lippincott-Raven Publishers.