Figure 5
Plot of anxiety (5a) and frustration (5b) ratings as a function of unpleasantness rating in COPD subjects during dyspnea caused by activities of daily living (ADL) and by a laboratory stimulus evoking air hunger. Open circles connected by line represent dyspnea during moderate and high PETCO2 during restricted ventilation in the laboratory; closed circle represents dyspnea experienced during activities of daily living, such as walking or climbing stairs. Scale maxima were defined as ‘Unbearable’ for unpleasantness and ‘most I can imagine’ for emotion. Error bars reflect standard errors.