Impact Prediction by Looming Visual Stimuli Enhances Tactile Detection

Abstract

From an ecological point of view, approaching objects are potentially more harmful than receding objects. A predator, a dominant conspecific, or a mere branch coming up at high speed can all be dangerous if one does not detect them and produce the appropriate escape behavior fast enough. And indeed, looming stimuli trigger stereotyped defensive responses in both monkeys and human infants. However, while the heteromodal somatosensory consequences of visual looming stimuli can be fully predicted by their spatiotemporal dynamics, few studies if any have explored whether visual stimuli looming toward the face predictively enhance heteromodal tactile sensitivity around the expected time of impact and at its expected location on the body. In the present study, we report that, in addition to triggering a defensive motor repertoire, looming stimuli toward the face provide the nervous system with predictive cues that enhance tactile sensitivity on the face. Specifically, we describe an enhancement of tactile processes at the expected time and location of impact of the stimulus on the face. We additionally show that a looming stimulus that brushes past the face also enhances tactile sensitivity on the nearby cheek, suggesting that the space close to the face is incorporated into the subjects' body schema. We propose that this cross-modal predictive facilitation involves multisensory convergence areas subserving the representation of a peripersonal space and a safety boundary of self.

Speed of reaction to sensory stimulation is enhanced during movement

“…The attention capture explanation is also supported by the RTs recorded in response to tactile stimulation delivered during the reach-to-grasp movement execution in a laboratory setting: RTs in the postmovement period, once the grasp of the goal object has taken place, are faster than during the execution period . Furthermore, it has recently been suggested that the enhancement effect of the visual looming stimuli on tactile events stems from a defensive mechanism, that is, we inherently perceive approaching objects as more dangerous, as compared to objects leaving our personal space (Clery, Guipponi, Odouard, Wardak, & Ben Hamed, 2015;Kandula, Hofman, & Dijkerman, 2015). Importantly, the attention-capture-like effect found in this study also supports the multisensory thesis concerning looming stimuli (Cappe, Thut, Romei, & Murray, 2009), since the ball arrival carries not only visual information, but also auditory information.…”

From multisensory integration in peripersonal space to bodily self‐consciousness: from statistical regularities to statistical inference

“…More precisely, the PPS constraint specifies that body signals occur within the limited space surrounding the body—the PPS—and hence for signals to bind with body‐related information they must occur within this space. In this line, recent work has depicted a more complete picture regarding the encoding and functional role of the PPS, and has revealed the stochastic and predictive nature of this particular form of spatial representation critical for bodily self‐consciousness. Thus, we propose that by highlighting the stochastic or statistical inference nature of PPS representation, as one fundamental component of bodily self‐consciousness, it may be possible to leverage recent advances in computational models dedicated to multisensory integration in the study of bodily self‐consciousness.…”

Impaired Cognitive Performance in Youth Athletes Exposed to Repetitive Head Impacts

“…The visual looming effect is purported to activate fast intercortical connections and increase sensorimotor function 32 and may even lead to an increase in cognitive function. Such effects, if present, could mask immediate negative effects from RHI.…”