title: Neural mechanisms of detecting and orienting attention toward unattended threatening somatosensory target stimuli. II. Intensity effects.
abstract: Negative potentials evoked by painful electrical stimulation of the sural nerve that occur at 100-180 ms poststimulus over the contralateral temporal scalp (CTN100-180) and at 130-200 ms over the fronto-central scalp (FCN130-200) exhibit unusual attention effects. That is, their amplitudes are larger when the painful evoking stimulus is unattended than when it is attended. In this experiment, I show that attention has no effect on the CTN100-180 evoked by a weak, nonthreatening sural nerve electrical stimulus. These data suggest that the generators of the CTN100-180, which include the somatosensory association areas in the parietal operculum, are specifically involved in detecting threatening somatosensory stimuli. The FCN130-200 showed a small increase in the unattended condition, which is consistent with the role of its medial prefrontal cortex generators in monitoring any situation that might require a change in attentional control.
authors: Department of Psychology, Clarkson University, Potsdam, NY 13699, USA. rdowman@clarkson.edu
authors: Robert
authors: R
authors: Dowman
mesh_terms: D000293:Adolescent; D000328:Adult; D001288:Attention / Q000502:physiology*; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000503:physiopathology; D003265:Contingent Negative Variation; D004569:Electroencephalography; D004597:Electroshock; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005239:Fear / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009415:Nerve Net / Q000503:physiopathology; D009949:Orientation / Q000502:physiology*; D010146:Pain / Q000503:physiopathology*; D017288:Pain Threshold / Q000502:physiology; D017397:Prefrontal Cortex / Q000503:physiopathology; D013216:Reflex, Startle / Q000502:physiology*; D013003:Somatosensory Cortex / Q000503:physiopathology*; D013497:Sural Nerve / Q000503:physiopathology