Optimal multisensory integration leads to optimal time estimation

Abstract

Our brain compensates sensory uncertainty by combining multisensory information derived from an event, and by integrating the current sensory signal with the prior knowledge about the statistical structure of previous events. There is growing evidence that both strategies are statistically optimal; however, how these two stages of information integration interact and shape an optimal percept remains an open question. In the present study, we investigated the perception of time as an amodal perceptual attribute. The central tendency, a phenomenon of biasing the current percept toward previous stimuli, is used to quantify and model how the prior information affects the current timing behavior. We measured the timing sensitivity and the central tendency for unisensory and multisensory stimuli with sensory uncertainty systematically manipulated by adding noise. Psychophysical results demonstrate that the central tendency increases as the uncertainty increases, and that the multisensory timing improves both the timing sensitivity and the central tendency bias compared to the unisensory timing. Computational models indicate that the optimal multisensory integration precedes the optimal integration of prior information causing the central tendency. Our findings suggest that our brain incorporates the multisensory information and prior knowledge in a statistically optimal manner to realize precise and accurate timing behavior.

Central tendency biases must be accounted for to consistently capture Bayesian cue combination in continuous response data

“…We model this as a two-step process, where observers first combine all of the relevant sensory information, forming a sensory estimate of the stimulus they must judge, before taking a weighted average of that sensory estimate and the central value to produce their response, or behavioural estimate. Our two-step model is supported by empirical findings that central tendency biases arise during reconstruction (or decoding), not encoding of stimulus features (Crawford et al, 2000) and, more importantly, by a model comparison suggesting that multisensory integration precedes a central tendency bias (Murai and Yotsumoto, 2018).…”

“…We have already alluded to a distinction between sensory variability (or sensory precision ) and behavioural variability (or behavioural precision ), but we will make that distinction explicit here. As central tendency biases appear to be introduced after the sensory estimate is formed (Crawford et al, 2000; Murai and Yotsumoto, 2018), comparing the variability of behavioural responses across different experimental conditions (e.g. when observers use their best single cue compared to multiple cues) will not reflect the reduction in variance, or gain in precision, that is afforded from taking a reliability-weighted average of sensory information, or the underlying combination effect E (Equation 1).…”

Grape skin fermentation by Lactobacillus fermentum CQPC04 has anti-oxidative effects on human embryonic kidney cells and apoptosis-promoting effects on human hepatoma cells

“…41 qRb is a tumor suppressor gene that regulates the cell cycle, programmed cell death, and autophagy. 42 The TGF-b/Smads signaling pathway is closely related to tumor occurrence and development. 43 Under normal conditions, TGF-b can control c-myc gene expression and RB phosphorylation, induce apoptosis, and upregulate TGF-b-mediated Smad7 expression, thus activating antiapoptotic factor NF-kB signaling pathway components The change makes cells tolerant to TGF-b, c-myc overexpression, and RB inhibition, thereby innitely increasing the cells, leading to tumorigenesis.…”

Cross-Modal Conflict Increases With Time-on-Task in a Temporal Discrimination Task

“…This initial modality difference in temporal information preciosity might strongly affect performance in trials with modality transition, for example, via the proactive interference effects as discussed above extensively. In addition, recent studies (Murai and Yotsumoto, 2016, 2018) suggest that the role of modalities in temporal processing is not necessarily manifested in a conflict between the modalities. In contrast, the brain might incorporate the multisensory information (i.e., visual and auditory information) to improve timing sensitivity.…”