Sequence-dependent sensitivity explains the accuracy of decisions when cues are separated with a gap

TL;DR

This study investigates how the order and timing of sequential cues influence decision accuracy, revealing that earlier evidence impacts later information processing and that the rate of evidence extraction varies with sequence position.

Contribution

The paper introduces a modified drift-diffusion model demonstrating that prior evidence affects subsequent evidence accumulation in sequential decision tasks.

Findings

Earlier evidence influences later evidence accumulation.

The rate of information extraction depends on whether the cue is first or second.

The model explains the stronger effect of the second pulse observed in experiments.

Abstract

Most decisions require information gathering from a stimulus presented with different gaps. Indeed, the brain process of this integration is rarely ambiguous. Recently, it has been claimed that humans can optimally integrate the information of two discrete pulses independent of the temporal gap between them. Interestingly, subjects' performance on such a task, with two discrete pulses, is superior to what a perfect accumulator can predict. Although numerous neuronal and descriptive models have been proposed to explain the mechanism of perceptual decision-making, none can explain human behavior in this two-pulse task. In order to investigate the mechanism of decision-making on the noted tasks, a set of modified drift-diffusion models based on different hypotheses were used. Model comparisons clarified that, in a sequence of information arriving at different times, the accumulated information of earlier evidence affects the process of information accumulation of later evidence. It was shown that the rate of information extraction depends on whether the pulse is the first or the second one. The proposed model can also explain the stronger effect of the second pulse as shown by Kiani et al. 2013.