Rhythmicity and cross-modal temporal cues facilitate detection

Abstract

Temporal structure in the environment often has predictive value for anticipating the occurrence of forthcoming events. In this study we investigated the influence of two types of predictive temporal information on the perception of near-threshold auditory stimuli: 1) intrinsic temporal rhythmicity within an auditory stimulus stream and 2) temporally-predictive visual cues. We hypothesized that combining predictive temporal information within- and across-modality should decrease the threshold at which sounds are detected, beyond the advantage provided by each information source alone. Two experiments were conducted in which participants had to detect tones in noise. Tones were presented in either rhythmic or random sequences and were preceded by a temporally predictive visual signal in half of the trials. We show that detection intensities are lower for rhythmic (vs. random) and audiovisual (vs. auditory-only) presentation, independent from response bias, and that this effect is even greater for rhythmic audiovisual presentation. These results suggest that both types of temporal information are used to optimally process sounds that occur at expected points in time (resulting in enhanced detection), and that multiple temporal cues are combined to improve temporal estimates. Our findings underscore the flexibility and proactivity of the perceptual system which uses within- and across-modality temporal cues to anticipate upcoming events and process them optimally.

Cortical entrainment to music and its modulation by expertise

“…A recent study (62) showed that rhythmicity (i.e., high temporal predictability) enhances detection, confirming a link between temporal and content processing. Similar effects occur in vision: reaction time in a detection task is modulated by the phase of delta oscillations (63).…”

The context-contingent nature of cross-modal activations of the visual cortex

“…When helpful to the goal-directed behaviour, regular/predictable stimuli will be continuously processed (i.e., selected) and utilised by the brain (e.g., Ten Oever et al 2014). However, stimulus regularity likewise seems to enable the observer to effectively inhibit irrelevant stimuli in situations where they are highly unlikely to directly facilitate the ongoing behaviour, e.g., in no-task setups, as in the current experiment.…”

“…In the case of naturalistic stimuli, e.g., speech, the natural delay between the visual and the subsequent auditory input is well known to facilitate comprehension (e.g., van Wassenhove et al, 2005). Recently, the mechanisms have been revealed by which a cross-talk between higher-level (language and top-down attention areas) areas and lower-level auditory cortices enables, currently unattended but potentially important, stimuli to become attended in realworld like, multi-speaker settings (i.e., the 'cocktail party' context; Zion-Golumbic et al, 2014). The fact that the present effects, obtained with simple acoustic information (tones), were localised to lateral occipital cortices is consistent with these findings and supports the notion of a privileged interplay between auditory cortices, involved in complex sound recognition (and, perhaps, also localisation), and visual cortices, involved in visual-object identification (often person recognition) (e.g., Blank et al, 2014).…”

“…In social situations, with many people speaking, seeing lip movements of the next speaker helps us know where to attend and to understand what will be said next (e.g., van Wassenhove et al, 2005;Zion-Golumbic et al, 2014). Notwithstanding, in laboratory settings even simple sounds are shown to modulate the brain processing and/or facilitate perception of visual objects.…”

“…More recently, the context has been revealed as an important source of top-down control over processing of multisensory information. While some studies demonstrated the role of long-term experience and learning (e.g., Froyen et al, 2009;Stevenson and Wallace, 2013;Barenholtz et al, 2014;Ten Oever et al, 2014;Matusz et al, 2015b), many focused on effects operating at shorter timescales, such as expectations and/or experiences built over the course of a single experimental session (e.g., Murray et al, 2004Murray et al, , 2005von Kriegstein and Giraud, 2006;Meylan and Murray, 2007;Rosenblum et al, 2007;Beierholm et al, 2009;Powers et al, 2009;Barakat et al, 2013;Chandrasekaran et al, 2009;Thelen et al, 2012Thelen et al, , 2014Matusz et al, 2015c;Altieri et al, 2015), or even across a pair of successive experimental trials Murray et al 2009;King et al 2012;Sarmiento et al, 2015). Considered together, the overwhelming evidence for the importance of context-based factors for stimulus processing across the senses and the concomitant limited existing data on the ACOP makes it plausible that irrelevant sounds activate the visual cortex in some contexts but not in others.…”