Neuroelectrical signs of selective attention to color in boys with attention-deficit hyperactivity disorder - Preliminary results of this study were presented at the 39th Meeting of the Society for Psychophysiological Research (SPR), Granada, Spain, October 6-10, 1999.

In order to gain insight into the functional and macroanatomical loci of vi sual selective processing deficits that may be basic to attention-deficit h yperactivity disorder (ADHD), the present study examined multi-channel even t-related potentials (ERPs) recorded from 7- to 11-year-old boys clinically diagnosed as having ADHD (n=24) and age-matched healthy control boys (n=24 ) while they performed a visual (color) selective attention task. The spati o-temporal dynamics of several ERP components related to attention to color were characterized using topographic profile analysis, topographic mapping of the ERP and associated scalp current density distributions, and spatio- temporal source potential modeling. Boys with ADHD showed a lower target hi t rate, a higher false-alarm rate, and a lower perceptual sensitivity than controls. Also, whereas color attention induced in the ER-Ps from controls a characteristic early frontally maximal selection positivity (FSP), ADHD b oys displayed little or no FSP. Similarly, ADHD boys manifested P3b amplitu de decrements that were partially lateralized (i.e., maximal at left tempor al scalp locations) as well as affected by maturation. These results indica te that ADHD boys suffer from deficits at both relatively early (sensory) a nd late (semantic) levels of visual selective information processing. The d ata also support the hypothesis that the visual selective processing defici ts observed in the ADHD boys originate from deficits in the strength of act ivation of a neural network comprising prefrontal and occipito-temporal bra in regions. This network seems to be actively engaged during attention to c olor and may contain the major intracerebral generating sources of the asso ciated scalp-recorded ER-P components. (C) 2001 Elsevier Science BY All rig hts reserved.