Accuracy and precision of matching inspired lung volume

Institute of Environmental Stress, University of California, Santa Barbara, California 93106 Three questions were asked: How accurately can lung volumes be reproduced? Do the underlying sensory continua of inspired lung volume subscribe to Weber’s law? Are planned inspirations more accurately reproduced than constrained inspirations? The ability to match inspired lung volume was investigated utilizing the psychophysical method of average error. Fourteen subjects participated in two different conditions in order to answer these questions. The results indicated that inspired lung volumes were reproduced much more accurately than had been previously reported. The sensitivity of change for planned inspirations was identical to that of constrained inspirations (k = 018). However, the absolute threshold was significantly greater for the constrained group. The underlying sensory continua subscribed to a generalized version of Weber’s law. These results are discussed within the context of our present knowledge of receptor information of movement.