THE CONTINUOUS PERFORMANCE-TEST REVISITED WITH NEUROELECTRIC MAPPING - IMPAIRED ORIENTING IN CHILDREN WITH ATTENTION DEFICITS

A total of 11 children with attention deficit disorder (ADD) and nine control children performed a continuous performance test (CPT) of the A-X type with concurrent neuroelectric brain mapping to assess prepara tory processing, purportedly mediated by the frontal lobes. This cued CPT task proved to be a highly specific task. The groups could be clea rly differentiated both at the behavioral and electrophysiological lev el. ADD children detected fewer signals and made more false alarms. Th ere were no major group differences in topographical distribution of t he event-related potential microstates, but ADD children displayed red uced global held power (GFP) in an early CNV/P3 microstate to cues. Th is indicated that impaired orienting to cues, rather than impaired exe cutive target processing, determines the initial processing stages in ADD. In comparison with data from the same task run in Utrecht, the sa me orienting deficit in clinically diagnosed ADHD children was demonst rated. Low resolution electromagnetic tomography (LORETA) estimated po sterior sources underlying these orienting processes and the orienting deficit. This argued against frontal lobe involvement at this stage a nd suggested involvement of a posterior attention system. (C) 1998 Els evier Science B.V. All rights reserved.