Group and individual relations between sensation magnitudes and their numerical estimates

Abstract

The study deals mainly with absolute magnitude estimation (AME) of the component loudnesses and the total loudness of pairs of heterofrequency, sequential tone bursts. Two kinds of relations are derived from the obtained group and individual data on the assumption of loudness additivity and a two-stage scaling model. They refer to numerical loudness estimates versus derived loudness magnitudes and to the loudness magnitudes versus tone sensation levels. The relations are validated by means of indirect and direct loudness matches. In an auxiliary experiment, the same subjects performed AMEs of subjective line lengths. The resulting group and individual relations between the numerical estimates and the underlying physical line lengths were found to be nearly the same as those between the numerical loudness estimates and the derived loudness magnitudes. The mutual consistency among the several sets of empirical and derived data strongly supports the assumptions of loudness additivity and the two-stage model.

The shape of the vibrotactile loudness function: The effect of stimulus repetition and skin-contactor coupling

“…Because it is possible that averaging the data could have minimized or distorted changes in slope (Van Doren, 1990;Zwislocki, 1983), the roles of the number of stimulus presentations and coupling arrangement on the shapes of the loudness functions were also analyzed by examining the data from the individual observers. The appropriate descriptions of the shapes of the loudness functions (one-or two-limbed) were determined by applying the two criteria described previously.…”

“…This series required the observers to make judgments of the magnitude of line lengths, a relatively easy task that appears to stabilize loudness scaling (S. S. Stevens, 1975;Zwislocki, 1983;Zwislocki & Goodman, 1980). The observers were given AME instructions modeled after those in Zwislocki (1983).…”

Prepulse inhibition of the startle eyeblink as an indicator of temporal summation

“…Zwislocki (1969Zwislocki ( , 1983 proposed a neural mechanism for temporal summation, involving a neural volley causing a change in the postsynaptic potential, with this change persisting for some time and then decaying. If new neural input occurs before the postsynaptic resting level is reached, the new input will be added to the residual potential caused by previous input.…”

Describing color appearance: Hue and saturation scaling

“…Also, subjects are not told that within a category they must assign numbers to reflect sensory ratios; the only requirement, which is implicit, is that they take whatever numbers they would have assigned to sensations in each category and then tell us the ratios of these values between categories. This may make the demands on the subjects more like those ofthe absolute magnitudeestimation techniques that have been advocated (e.g., Gescheider & Hughson, 1991;Zwislocki, 1983;Zwislocki & Goodman, 1980). Figure 1 shows data from a typical subject from a lengthy study of color vision across the retina .…”