If oddball-ness was the sole factor in orienting attention to the target, a dilation of subjective duration should always be observed in our conditions because the target always differed from the standards in features and/or duration; this is not what we observed in the Recede and Reverse experiments, suggesting that it is the salience of the target that matters.
However, the current results urge caution about using temporal production as an index of subjective duration in this context.
Most studies of this phenomenon have measured the strength of the motion aftereffect by its subjective duration, a measure that is known to be subject to the Rosenthal compliance effect (Sinha, 1952).
In the Reverse experiment (looming standards, steady target), we observed a robust compression of subjective duration in visual and auditory-visual but not in auditory presentations; these results further highlight the role of contextual salience in the experience of time, at least in vision.
Instead motor involvement reflected perceptual changes in the subjective duration of a single stimulus sequence, as a result of its fluent or nonfluent motoric organization.
Under the accumulator/switch framework, the distortions of time we observed could thus be interpreted as follows: dilation and compression of subjective duration entails a faster and slower rate of the pacemaker, and/or a shorter and longer latency of the switch, respectively.
Subjective time is not isomorphic to physical time [1]: the subjective duration of an event can be systematically overestimated, a phenomenon referred to as "time dilation", "time subjective expansion" [2] or "chronostasis" [3], [4].
Therefore, looming standards lead to the compression of subjective duration of a steady visual and auditory-visual target but not of an auditory target.
Additionally, the time scale of the stimulus and the task used to measure participants' subjective duration have a bearing on the neural mechanisms involved in temporal processing [11], [12], [13], [14].
The subjective duration of a stimulus depends on its non-temporal properties, so there may be more noise in the comparison of the current duration with the memory standard when the two intervals are demarcated by different visual stimuli, leading to poorer discrimination.
