Interactions among behavioral style, ventilatory drive, and load recognition.

We previously demonstrated that specific behavioral styles influenced recognition of resistive loads to breathing. However, the basis for this finding remained unclear. Because others have found a relationship between behavioral style and ventilatory drive, we evaluated the relationships among resting ventilatory drive, behavioral style, and recognition of loads to breathing. Twelve healthy subjects were divided into 3 behavioral style groups by the MMPI Panic-Fear Scale. Inspiratory neuromuscular activity, detected by mouth occlusion in relaxed subjects, served as an index of resting ventilatory drive, and the resistance added to inspiration recognized during 50% of the applications was termed threshold resistance. Across all subjects, there was a significant inverse correlation between resting inspiratory neuromuscular activity and the amount of added resistance required for recognition. The higher the ventilatory drive the lower the added resistance needed for recognition. Anxious, dependent subjects had lower resting ventilatory drive and lower mean inspiratory flow rates. They required more added resistance for recognition than generally adaptive or rigidly independent subjects who had higher resting neuromuscular activity and lower detection thresholds. We conclude: (1) that the level of resting ventilatory drive may play a role in the ability to recognize added resistive loads to breathing, and (2) that behavioral style and level of resting ventilatory drive appear related.