Studies in psychophysiology and behavioral medicine have uncovered associations among psychological processes, behavior, and lung function. However, methodological issues specific to the measurement of mechanical lung function have rarely been discussed. This report presents an overview of the physiology, techniques, and experimental methods of mechanical lung function measurements relevant to this research context. Techniques to measure lung volumes, airflow, airway resistance, respiratory resistance, and airflow perception are introduced and discussed. Confounding factors such as ventilation, medication, environmental factors, physical activity, and instructional and experimenter effects are outlined, and issues specific to children and clinical groups are discussed. Recommendations are presented to increase the degree of standardization in the research application and publication of mechanical lung function measurements in psychophysiology.

We studied the modulation of oscillatory resistance (Ros) by viewing and imagery of affective pictures. Thirty nonasthmatic participants viewed 36 affective slides precategorized as positive, neutral, and negative in valence. Each picture was presented for 15 s, followed by an imagery epoch of 15 s. Ros, facial EMGs, respiration, skin conductance response, heart period, and respiratory sinus arrhythmia were measured throughout the session, as well as viewing time and ratings of pleasure, arousal, and interest. Increases of Ros were observed for negative pictures, and little changes for positive or neutral pictures. Other physiological parameters did not mirror this response pattern, leaving no clear indication for a ventilatory or vagal origin of Ros changes. Overall differences between behavioral contexts of visual processing and imagery revealed evidence for a coupling of cardiac and respiratory responses, which included changes in Ros. The findings in Ros are discussed in the light of earlier discrepant findings on the affective modulation of airway resistance and cardiac activity.

We tested the assumption that the slope of the within-individual regression equation of respiratory sinus arrhythmia (RSA) normalized by tidal volume (VT) upon respiratory cycle length (TTOT) can characterize ventilatory RSA modulation independent of cardiac vagal tone, whereas the intercept is varying as a function of vagal tone. We also explored whether a variation of VT is necessary to estimate slopes reliably. Four 3-min sequences paced at 8–18 cycles/min were performed supine and standing. Participants also breathed the same sequences in supine posture with voluntarily varying VT. The mean slope of RSA/VT upon TTOT was identical, and the mean intercept was lower for standing than supine (spontaneous VT) conditions. Stability of slopes was low between body postures, and was higher between spontaneous VT versus varying VT at the same body posture. The regression of RSA/VT upon TTOT allows for a valid estimation of ventilatory influences on RSA.

The impact of static muscle tension on total respiratory resistance (TRR) was examined. Participants (24 healthy, 24 asthmatic) performed biofeedback-assisted sequences of tensing (15 s) and relaxing (20 s) forehead and forearm muscles. Muscle tension levels were 40% or 80% of the maximum individual force. Oscillatory TRR, electromyograms, ventilation, heart period, and respiratory sinus arrhythmia were recorded. Baseline TRR did not change over the session as a whole. Decreases in TRR during forehead tension in both groups were accompanied by increases in end-expiratory volume, which could have mediated TRR changes. During forearm tension, decreases in TRR with minimal ventilation changes were only observed in healthy participants, whereas asthmatic patients revealed marked increases in respiratory volume and flow. These results indicate that static muscle activity and TRR are negatively related. Ventilatory changes can exaggerate or diminish evidence for this relationship.