title: Multi-site phasic neural activity mediates the execution of an auditory continuous performance task: a PET and electrophysiological study.
abstract: OBJECTIVE
  We studied an auditory continuous performance task with positron emission tomography (PET) and EEG-derived current density reconstructions (CDRs) to define the spatial and temporal aspects of auditory attention.
  
  
  METHODS
  The CDRs were employed to segregate responses to targets and non-targets at sites identified by PET. We then studied the time course of brain activity using statistical parametric mapping (SPM) of the CDR data.
  
  
  RESULTS
  In contrast to target EEG activity, non-targets did not produce significant peaks after 300 ms. Pre-300 ms biphasic activation of auditory, left posterior frontal, left supplemental, and primary motor cortices and the anterior cingulate (AC) and biphasic suppression of posterior cingulate and occipital cortex were identical for targets and non-targets and may mediate the target non-target decision. SPM analysis of post-300 ms CDRs showed cingulate cortices were the first to be reactivated, remained active through 672 ms, and were accompanied by reactivation and deactivation of the same sites observed in the pre-P300 responses.
  
  
  CONCLUSIONS
  The cingulate may play an important role in post-decisional activity and control activity at other sites involved in post-decisional cognitive processing.
authors.affiliation: VA Western NY Healthcare System, University at Buffalo, Buffalo, NY 14215, USA. ahl@buffalo.edu
authors.forename: Alan H
authors.initials: AH
authors.lastname: Lockwood
authors.forename: David S
authors.initials: DS
authors.lastname: Wack
authors.forename: Ralph H B
authors.initials: RH
authors.lastname: Benedict
authors.forename: Mary Lou
authors.initials: ML
authors.lastname: Coad
authors.forename: Joan E
authors.initials: JE
authors.lastname: Sussman
authors.forename: Robert F
authors.initials: RF
authors.lastname: Burkard
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001288:Attention; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods*; D004569:Electroencephalography; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D049268:Positron-Emission Tomography