The major focus of this research proposal is on the early processing of acoustic information. The principal tool used in this endeavor is an event-related potential termed the mismatch negativity (MMN). Research with the MMN has uncovered a system located in auditory cortex that defects change in the acoustic environment on a automatic, pre-attentive basis. The proposal has four basic aims.
One aim i s to determine whether the system tracks sources of sounds, or objects rather than tracking acoustic features across objects. Another aim is to examine the system's ability to be set for certain stimuli prior to conscious detection, and in that sense be able to predict future stimuli. Three experiments will focus on this issue. One re-examines a previous study which concluded that the MNM system is not affected by the occurrence of predictable stimuli. A second will ascertain whether a change in one acoustic feature can set the MNM system for a change in a different feature. A third experiment will determine whether conscious awareness of a forthcoming acoustic change will affect the MMN system. Another aim is to characterize the memory associated with the MMN as being different from sensory memory. One experiment will test the hypothesis that the memory is not accessible to conscious processing. Another will examine whether it is common for these memories to become dormant and be reactivated by a single reminder stimulus. Finally, we will attempt to provide more evidence that the MMN system is pre-attentive and automatic by showing that features of acoustic stimuli are analyzed in parallel by the MMN system and in series by conscious processing.
|Leitman, David I; Sehatpour, Pejman; Shpaner, Marina et al. (2009) Mismatch negativity to tonal contours suggests preattentive perception of prosodic content. Brain Imaging Behav 3:284-91|
|De Sanctis, Pierfilippo; Ritter, Walter; Molholm, Sophie et al. (2008) Auditory scene analysis: the interaction of stimulation rate and frequency separation on pre-attentive grouping. Eur J Neurosci 27:1271-6|
|Saint-Amour, Dave; De Sanctis, Pierfilippo; Molholm, Sophie et al. (2007) Seeing voices: High-density electrical mapping and source-analysis of the multisensory mismatch negativity evoked during the McGurk illusion. Neuropsychologia 45:587-97|
|Ritter, Walter; De Sanctis, Pierfilippo; Molholm, Sophie et al. (2006) Preattentively grouped tones do not elicit MMN with respect to each other. Psychophysiology 43:423-30|
|Molholm, Sophie; Martinez, Antigona; Ritter, Walter et al. (2005) The neural circuitry of pre-attentive auditory change-detection: an fMRI study of pitch and duration mismatch negativity generators. Cereb Cortex 15:545-51|
|Frangos, Jason; Ritter, Walter; Friedman, David (2005) Brain potentials to sexually suggestive whistles show meaning modulates the mismatch negativity. Neuroreport 16:1313-7|
|Molholm, Sophie; Ritter, Walter; Javitt, Daniel C et al. (2004) Multisensory visual-auditory object recognition in humans: a high-density electrical mapping study. Cereb Cortex 14:452-65|
|Deacon, Diana; Dynowska, Anna; Ritter, Walter et al. (2004) Repetition and semantic priming of nonwords: implications for theories of N400 and word recognition. Psychophysiology 41:60-74|
|Winkler, Istvan; Sussman, Elyse; Tervaniemi, Mari et al. (2003) Preattentive auditory context effects. Cogn Affect Behav Neurosci 3:57-77|
|Sussman, Elyse; Winkler, Istvan; Kreuzer, Judith et al. (2002) Temporal integration: intentional sound discrimination does not modulate stimulus-driven processes in auditory event synthesis. Clin Neurophysiol 113:1909-20|
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