Sequential dependence and Vierordt’s law

Sequential dependence and Vierordt’s law

Featured, Research
Perceptual bias caused by sequential dependence has attracted lots of attention recently. The phenomenon is not new. For example, 150 years ago Vierordt has found a classic central tendency effect using duration reproduction. However, recently Stefan Glasauer and me looked into the original study conducted by Vierordt (1868), and found actually Vierordt wrongly used the method developed by Fechner (1860). That is, Vieordt introduced randomization in the 'method of average error' that Fechner invented. Using iterative Bayesian updating we are able to replicate the original Vierordt's results. More interestingly, we found that the randomization is the main factor that causes the classic Vierordt's law. That is, the short duration is often overestimated and long duration underestimated. We conducted a new study with two different sequences, sampled from the same distribution,…
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What you see depends on what you hear: temporal averaging and crossmodal integration

What you see depends on what you hear: temporal averaging and crossmodal integration

Featured, Research
In our multisensory world, we often rely more on auditory information than on visual input for temporal processing. One typical demonstration of this is that the rate of auditory flutter assimilates the rate of concurrent visual flicker. To date, however, this auditory dominance effect has largely been studied using regular auditory rhythms. It thus remains unclear whether irregular rhythms would have a similar impact on visual temporal processing, what information is extracted from the auditory sequence that comes to influence visual timing, and how the auditory and visual temporal rates are integrated together in quantitative terms. We investigated these questions by assessing, and modeling, the influence of a task-irrelevant auditory sequence on the type of "Ternus apparent motion": group motion versus element motion. The type of motion seen critically depends…
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Inter-trial effects in visual search

Inter-trial effects in visual search

Featured, Research
Many previous studies on visual search have reported inter-trial effects, that is, observers respond faster when some target property, such as a defining feature or dimension, or the response associated with the target repeats versus changes across consecutive trial episodes. However, what processes drive these inter-trial effects is still controversial. Here, we investigated this question using a combination of Bayesian modeling of belief updating and evidence accumulation modeling in perceptual decision-making. In three visual singleton ('pop-out') search experiments, we explored how the probability of the response-critical states of the search display (e.g., target presence/absence) and the repetition/switch of the target-defining dimension (color/ orientation) affect reaction time distributions. The results replicated the mean reaction time (RT) inter-trial and dimension repetition/switch effects that have been reported in previous studies. Going beyond this,…
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