Biology subjects

Pleche, C.

Publications and source records attributed to Pleche, C..

3 recordsLinked to original sources

bioRxiv2026

Invisible flashes bias spatial coding in the auditory system

Information integration is widely considered fundamental for human consciousness. Combining spatial ventriloquism and dynamic continuous flash suppression, this psychophysics-EEG study investigated how invisible flashes influence spatial perception of sounds. We show that invisible flashes, even when mislocalized by observers, bias observers perceived sound location. EEG multivariate pattern analyses unravelled that the locations of invisible flashes are encoded in early (150-250ms) neural activity. Crucially, even though this visuospatial information rapidly dissipates for invisible mislocalized flashes, being no longer decodable from neural activity after 300ms, it progressively biases neural encoding of sound location (300-600ms), thereby ultimately inducing a perceptual ventriloquist illusion. Our results demonstrate that subjective awareness is not a prerequisite for integrating information across the senses. Spatial information that dissipates from the visual system and evades awareness biases neural encoding and perception of sound location. These results pose challenges for leading theories of consciousness as a unified all-or-none phenomenon.

neuroscience↗

bioRxiv2020

No evidence for ultra-fast consolidation in probabilistic learning, but time-dependent improvements in general skills

Memory consolidation has mainly been investigated for extended periods, from hours to days. Recent studies suggest that memory consolidation can also occur within shorter periods, from minutes to seconds. Our study aimed at determining (1) whether short rest periods lead to improvements in implicit probabilistic sequence learning and (2) whether length of rest duration influences such offline improvements. Participants performed an implicit probabilistic sequence learning task throughout 45 blocks. Between blocks, participants were allowed to rest and then to continue the task in their pace. The overall reaction times (general skill learning) shortened from pre- to post-rest periods, and this improvement was increased for longer rest durations. However, probabilistic sequences knowledge decreased in these periods, and this decrement was not related to the length of rest duration. These results suggest that (1) general skill learning but not probabilistic sequence knowledge benefits from short rest periods and, possibly, from memory consolidation, (2) ultra-fast offline improvements in general skills, but not forgetting in probabilistic sequence knowledge, are time-dependent. Overall, our findings highlight that ultra-fast consolidation differently affects distinct cognitive processes.

neuroscience↗

bioRxiv2019

Retrieval of a well-established skill is resistant to distraction: evidence from an implicit probabilistic sequence learning task

The characteristics of acquiring new sequence information under dual-task situations have been extensively studied so far. Such a concurrent task has often been found to affect performance. In real life, however, we mostly perform a secondary task when the primary one is already well-acquired. The effect of a secondary task on the ability to retrieve well-established sequence representations remains elusive. The present study investigates whether accessing a well-acquired probabilistic sequence knowledge is affected by a concurrent task. Participants acquired non-adjacent regularities in a perceptual-motor implicit probabilistic sequence learning task. After a 24-hour offline period, participants were tested on the same sequence learning task under dual-task or single-task conditions. Here we show that although the secondary task significantly prolonged the overall reaction times in the primary task, the access to the previously learned probabilistic representations remained intact. Our results highlight the importance of studying the dual-task effect not only in the learning phase but also during memory access.

neuroscience↗