The impairing effect of dyspnea on response inhibition.

Dyspnea (=breathlessness) is an aversive and threatening symptom in various prevalent diseases. Established treatment procedures aim for behavioral changes in dyspneic patients in order to treat dyspnea successfully. To achieve these behavioral changes, response inhibition as one key executive function for goal-directed behavior is an important prerequisite. However, the impact of dyspnea on response inhibition is widely unknown. Therefore, the present study aimed at testing whether experimentally induced dyspnea would impair response inhibition. Thirty-six healthy participants performed the color-word Stroop task during an unloaded baseline and a resistive load-induced dyspnea condition. Response inhibition was investigated using behavioral measures (reaction time, accuracy) and, based on literature, the late positive complex (LPC) in the electroencephalogram. Furthermore, the N400 was investigated in an exploratory analysis. The results showed significantly reduced accuracy for incongruent compared to congruent color-words in the Stroop task during the dyspnea condition (p < .001) which was paralleled by a smaller LPC and a more negative centro-parietal N400 for incongruent color-words during the dyspnea compared to the baseline condition (p < .05). Possibly, during dyspnea more neural resources are allocated towards the semantic processing of incongruent color-words indexed as the N400 which are then not available for the partly overlapping LPC as an index for response inhibition. These findings demonstrate that resistive load-induced dyspnea has an impairing effect on response inhibition in healthy participants, both in terms of behavioral performance and respective neural processing. This might impair treatment efforts aimed at behavioral changes in patients suffering from dyspnea.