Operating in a Multisensory Context: Assessing the Interplay Between Multisensory Reaction Time Facilitation and Inter-sensory Task-switching Effects

Luke H. Shaw, Edward G. Freedman, Michael J. Crosse, Eric Nicholas, Allen M. Chen, Matthew S. Braiman, Sophie Molholm, John J. Foxe

Research output: Contribution to journalArticlepeer-review

21 Scopus citations

Abstract

Individuals respond faster to presentations of bisensory stimuli (e.g. audio-visual targets) than to presentations of either unisensory constituent in isolation (i.e. to the auditory-alone or visual-alone components of an audio-visual stimulus). This well-established multisensory speeding effect, termed the redundant signals effect (RSE), is not predicted by simple linear summation of the unisensory response time probability distributions. Rather, the speeding is typically faster than this prediction, leading researchers to ascribe the RSE to a so-called co-activation account. According to this account, multisensory neural processing occurs whereby the unisensory inputs are integrated to produce more effective sensory-motor activation. However, the typical paradigm used to test for RSE involves random sequencing of unisensory and bisensory inputs in a mixed design, raising the possibility of an alternate attention-switching account. This intermixed design requires participants to switch between sensory modalities on many task trials (e.g. from responding to a visual stimulus to an auditory stimulus). Here we show that much, if not all, of the RSE under this paradigm can be attributed to slowing of reaction times to unisensory stimuli resulting from modality switching, and is not in fact due to speeding of responses to AV stimuli. As such, the present data do not support a co-activation account, but rather suggest that switching and mixing costs akin to those observed during classic task-switching paradigms account for the observed RSE.

Original languageEnglish (US)
Pages (from-to)122-135
Number of pages14
JournalNeuroscience
Volume436
DOIs
StatePublished - Jun 1 2020

Keywords

  • attention
  • crossmodal
  • multisensory
  • race model
  • redundant signals effect
  • task-switching

ASJC Scopus subject areas

  • General Neuroscience

Fingerprint

Dive into the research topics of 'Operating in a Multisensory Context: Assessing the Interplay Between Multisensory Reaction Time Facilitation and Inter-sensory Task-switching Effects'. Together they form a unique fingerprint.

Cite this