Reaction time as a stochastic process implemented by functional brain networks

Abstract

Many studies focus on anatomical brain connectivity in an effort to explain the effect of practice on reaction time (RT) that is observed in many cognitive tasks. In this commentary, we suggest that RT reflects a stochastic process that varies in each single repetition of any cognitive task and cannot be attributed only to anatomical properties of the underlying neuronal circuit. Based on recent evidence from Magnetoencephalographic, Electroencephalographic, and fMRI studies, we further propose that the functional properties of key brain areas and their self-organization into functional connectivity networks contribute to the RT and could also explain the effects of training on the distribution of the RT.

Reaction Time Is Negatively Associated with Corpus Callosum Area in the Early Stages of CADASIL

“…While it may be tempting to look deeper into the relationships between reaction time and specific brain structure and/or networks, one must keep in mind that even in healthy subjects, the mechanisms underlying reaction time are strongly debated, with some authors considering it a stochastic process unrelated to specific brain areas or networks. 21 Note that the main assumption underlying our results is that reaction time involves efficient interhemispheric cooperation. Further studies including more advanced methods such as assessment of fiber tracts, as previously performed in CADASIL, will be needed to further understand the mechanisms of reaction time slowing in this disorder.…”

Information Processing Speed in Ageing: Is it task dependent?

“…More trials can invoke fatigue or reduced sustained attention [Fernaeus et al 2013] and result in slower RT performance particularly by the end of the testing period. Controversially, in contrast high numbers of trials can have opposite effect and improve RT performance due to practice effects [Yotsumoto et al 2015;Siettos and Smyrnis 2017].…”

“…A high number of trials in a single study can invoke fatigue , reduce sustained attention particularly towards the end of the test period [Fernaeus et al 2013] or reduce the level of alerting required with sustained performance [Voelker, Rothbart and Posner 2016] and as a result RT performance can become slower throughout the test especially towards the end. In contrast a high number of trials may, to some degree, improve RT performance and reduce age-related decline in cognitive function due to repeated practice from performing multiple trials [Yotsumoto et al 2015;Siettos and Smyrnis 2017].…”