EVENT-RELATED POTENTIALS TO INSPIRATORY FLOW-RESISTIVE LOADS IN YOUNG-ADULTS - STIMULUS MAGNITUDE EFFECTS

Event-related potentials were recorded to brief presentations of four levels of inspiratory flow-resistive loads in young adults. We labeled the loads according to the level of resistance they provided subjecti vely: sub-threshold (0.34 cmH(2)O/1 per s), near-threshold (4.01 cmH(2 )O/1 per s), intermediate (10.4 cmH(2)O/1 per s), and near-occlusion ( 57.5 cmH(2)O/1 per s). No discernible ERPs were elicited by the undete cted, sub-threshold stimulus but late components of the ERP (P2, N2, a nd P3) were observed to each of the three larger stimuli. They were re lated, in part, to behavioral judgments obtained during the stimulus p eriods. Both the latency and amplitude of the ERP components varied sy stematically as a function of stimulus magnitude, in a manner comparab le to that observed in ERP paradigms using auditory and visual stimuli . Thus, the data show that event-related potentials to breathing are s ensitive to physiologic effects of resistive loads present at the onse t of inspiration. Respiratory ERPs may be used to infer sensory and pe rceptual responses to increases in airflow resistance and, accordingly , may relate to the perception of airflow obstruction in patient popul ations. (C) 1998 Elsevier Science B.V. All rights reserved.