The functional role of serial dependence

Abstract

The world tends to be stable from moment to moment, leading to strong serial correlations in natural scenes. As similar stimuli usually require similar behavioural responses, it is highly likely that the brain has developed strategies to leverage these regularities. A good deal of recent psychophysical evidence is beginning to show that the brain is sensitive to serial correlations, causing strong drifts in observer responses towards previously seen stimuli. However, it is still not clear that this tendency leads to a functional advantage. Here, we test a formal model of optimal serial dependence and show that as predicted, serial dependence in an orientation reproduction task is dependent on current stimulus reliability, with less precise stimuli, such as low spatial frequency oblique Gabors, exhibiting the strongest effects. We also show that serial dependence depends on the similarity between two successive stimuli, again consistent with the behaviour of an ideal observer aiming at minimizing reproduction errors. Lastly, we show that serial dependence leads to faster response times, indicating that the benefits of serial integration go beyond reproduction error. Overall our data show that serial dependence has a beneficial role at various levels of perception, consistent with the idea that the brain exploits the temporal redundancy of the visual scene as an optimization strategy.

Probabilistic representation in human visual cortex reflects uncertainty in serial decisions

“…Our work differs in that we focus on the temporal predictability of sensory inputs from one moment to the next. Others have suggested that serial dependence effects in perception might reflect an advantageous sensory integration strategy employed by the brain to improve behavior (Cicchini et al, 2014(Cicchini et al, , 2017(Cicchini et al, , 2018Fischer and Whitney, 2014). Very few of these studies, however, have cast this notion in an explicit normative framework.…”

Build-up of serial dependence in color working memory

“…Serial dependence, some argue, reflects the world's tendency to be stable 2,14,23 . The reasoning is that because similar stimuli usually elicit similar behavior, the brain would incorporate mechanisms to exploit these patterns 23 .…”

“…Serial dependence, some argue, reflects the world's tendency to be stable 2,14,23 . The reasoning is that because similar stimuli usually elicit similar behavior, the brain would incorporate mechanisms to exploit these patterns 23 . Along these lines, a recent study has shown that systematic biases in color working memory change in the course of an experimental session to adapt to stimulus statistics 27 , arguing that systematic biases seen in delayed-estimation of color reflect real-world statistics.…”

“…In particular, paradigms including delayed-estimations of different visual features 2 , such as orientation 9,11,15 , numerosity 19 , location 3,20,21 , facial identity 22 or body size 13 . It has been speculated that these ubiquitous attractive biases are a consequence of the world's tendency to be stable, and have the functional role of averaging internal noise 2,11,14,23 . Some have further argued that serial dependence is of adaptive nature, changing its strength depending on the stimuli statistics 2,11,14,16,23 .…”

“…It has been speculated that these ubiquitous attractive biases are a consequence of the world's tendency to be stable, and have the functional role of averaging internal noise 2,11,14,23 . Some have further argued that serial dependence is of adaptive nature, changing its strength depending on the stimuli statistics 2,11,14,16,23 . Color, which is strongly correlated in natural scenes 24 , has never been studied with regard to its serial dependencies, possibly due to its strong systematic biases [25][26][27] .…”