Identification and Bisection of Temporal Durations and Tone Frequencies: Common Models for Temporal and Nontemporal Stimuli.

Abstract

This paper addresses two questions. At a general level, our concern is with whether human identification and discrimination of short temporal durations can be described in terms of the same principles that are known to characterise identification and discrimination of other simple perceptual stimuli (e.g., weights, loudnesses, or line lengths). Is a unified account possible? Recent models of timing have been developed independently from earlier traditions of modeling perceptual identification and discrimination; here in contrast we argue that similar principles may apply in both cases.A second, more specific, issue that we address concerns shifts in the temporal bisection point (the duration that is equally likely to be judged the same as the shortest or longest magnitude in a stimulus set). Several models of timing have proposed accounts of bisection point shifts that are specific to temporal processing; here we argue that a more general account of bisection point shifts can be given in terms of a model developed outside the temporal domain: Range Frequency Theory (RFT; e.g., Parducci, 1965Parducci, , 1995. The predictions of this claim are explored with a simple mathematical model, which we term Temporal Range Frequency Theory, and tested in two experiments. Models of timing.Over the past decade, understanding of human timing has been advanced through the use of temporal generalization and temporal bisection tasks. In the temporal generalization task, participants are exposed to a standard stimulus of a fixed duration. They then judge whether or not subsequently presented stimuli are of the same duration as the standard. Here we focus on temporal bisection tasks, a variety of which have been developed for use with human adults and children

Discrimination and representation of relative numerosity in a bisection task by pigeons

“…BPs can be shifted leftward, toward the geometric mean, if items are logarithmically, rather than linearly, spaced (Allan, 2002;Wearden & Ferrara, 1995). This effect appears to depend on the ratio of the longest/largest to shortest/smallest stimuli: With large long:short ratios (e.g., 9:1), the effect of stimulus distribution is much greater than with small long:short ratios (e.g., 4:1) (Brown et al, 2005;Wearden & Ferrara, 1996). For humans, a long:short ratio of 2:1 or less will generate bisection at the geometric mean and no effect of stimulus distributions, whereas values greater than 2:1 will produce bisection at the arithmetic mean and effects of stimulus spacing.…”

“…The location of BPs in temporal discriminations depends on several procedural factors, and these might also affect numerical bisection (Brown, McCormack, Smith, & Stewart, 2005). One factor is whether the spacing of stimulus values is logarithmic or linear.…”

Can we use verbal estimation to dissect the internal clock? Differentiating the effects of pacemaker rate, switch latencies, and judgment processes

“…The most likely explanation is that judgments of a given stimulus are partly based on comparisons with the other items in the experimental ensemble. For example, Brown et al (2005) found that temporal bisection curves depend on the skew of the distribution of to-be-judged intervals. Similarly, comparison of the non-temporal properties of the items in the stimulus set also shapes judgments of duration.…”

How do changes in speed affect the perception of duration?

“…For example, G.D.A. Brown et al (2005) found that judgments of durations assimilated towards the stimulus presented on the previous trial. The precise mechanism underlying the effects of changes in stimulus speed on the perceived duration of subsequent items is a topic for future investigation.…”