Kappa effect

Abstract: In 3 experiments, the authors studied the organization of spatiotemporal information in memory. Stimuli consisted of configurations of dots, presented sequentially. The stimuli were either proportional, with interdot distances corresponding to interdot durations, or not proportional, with interdol distances not corresponding to interdot durations. After a learning phase, participants reproduced the spatial (Experiment 1), temporal (Experiment 2), or spatial and temporal (Experiment 3) characteristics of the target 60 times in succession. In the nonproportional conditions, effects of variable interdot durations or distances on the reproduction of, respectively, constant distances (tau effect) or durations (kappa effect) were observed, whereas no such effects were observed when variable distances or durations were to be produced. Tau and kappa effects influenced the accuracy but not the variability of responses. The results are discussed in light of the distinction between properties of the stabilized mental image and the process of stabilization.

Abstract: THE new phenomenon in time judgment, described by Cohen, Hansel and Sylvester1 and called by them the kappa effect, is independently confirmed in the following set of observations. These observations have been elicited under different conditions, by another experimental procedure, and over a further range of time-intervals than those described by the above authors.

Abstract: Observers were presented stimulus patterns consisting of a sequence of three laterally displaced light flashes, which defined two spatial intervals and two temporal intervals. The position and time of the second flash were varied factorially, and observers were asked to make relative judgments of either the two spatial intervals or the two temporal intervals. “Induction” effects of stimulus timing on spatial judgments and of stimulus spacing on temporal judgments were both found; however, the directionality of these effects differed between subjects. The results are inconsistent with the hypothesis, derived from previous findings, that such effects are determined primarily by a tendency toward perceiving constant velocity of apparent motion; it is proposed that the directionality of the induction effects is determined largely by the strategy adopted by the observer for combining spatial and temporal stimulus information.

Abstract: The tau effect, an effect of temporal intervals on the perception of spatial separation or sensory difference, has been observed in various sense modalities, including pitch bisection judgments in audition. However, systematic studies on the mechanism of the auditory tau effect have been rather scarce. In the present study, experiments were carried out using the AXB method to investigate the auditory tau effect on the pitch perception of pure tones (Experiment 1), the auditory tau effect on perception of the /e/-/i/, /iA/e/, /I/-/i/, and IM-lll continua (Experiment 2), and the kappa effect—an effect of sensory differences on the perception of temporal intervals—on the perception of pure tones and synthetic vowels (Experiment 3). The results demonstrated that the auditory tau effect occurs not only in the pitch perception of pure tones, but also in the phonetic perception of the fU-iil and /iA/I/ continua of synthetic vowels. The reverse pattern of results was obtained in the /e/-/i/ and /iA/e/ continua. The kappa effect was found both in the pitch perception of pure tones and in phonetic judgments of synthetic vowels. These findings suggest that the interaction between temporal interval and pitch (or phonetic) perception can be explained on the basis of the integration of forward and backward context effects, and that the auditory tau and kappa effects occur at an early stage of auditory information processing.