Multisensory Research最新文献

The concept of embodiment has been used in multiple scenarios, but in cognitive neuroscience it normally refers to the comprehension of the role of one's own body in the cognition of everyday situations and the processes involved in that perception. Multisensory research is gradually embracing the concept of embodiment, but the focus has mostly been concentrated upon audiovisual integration. In two experiments, we evaluated how the likelihood of a perceived stimulus to be embodied modulates visuotactile interaction in a Simultaneity Judgement task. Experiment 1 compared the perception of two visual stimuli with and without biological attributes (hands and geometrical shapes) moving towards each other, while tactile stimuli were provided on the palm of the participants' hand. Participants judged whether the meeting point of two periodically-moving visual stimuli was synchronous with the tactile stimulation in their own hands. Results showed that in the hand condition, the Point of Subjective Simultaneity (PSS) was significantly more distant to real synchrony (60 ms after the Stimulus Onset Asynchrony, SOA) than in the geometrical shape condition (45 ms after SOA). In experiment 2, we further explored the impact of biological attributes by comparing performance on two visual biological stimuli (hands and ears), that also vary in their motor and visuotactile properties. Results showed that the PSS was equally distant to real synchrony in both the hands and ears conditions. Overall, findings suggest that embodied visual biological stimuli may modulate visual and tactile multisensory interaction in simultaneity judgements.

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has spread through more than 180 countries, leading to diverse health systems overload around the world. Because of the high number of patients and the supply chain disruption, it generated a shortage of medical devices and personal protective equipment. In this context, initiatives from the additive manufacturing community emerged to fight the lack of devices. Diverse designs were produced and are currently being used in hospitals by patients and health workers. However, as some devices must follow strict standards, these products may not fulfill these standards. Therefore, to ensure the user's health, there is a need for understanding each device, their usage, and standards. This study reviews the use of additive manufacturing during COVID-19 pandemic. It gathers the source of several 3D printed devices such as face shields, face masks, valves, nasopharyngeal swabs, and others, discussing their use and regulatory issues. In this regard, the major drawbacks of the technology, addressed for the next pandemic scenario, are highlighted. Finally, some insights of the future of additive manufacturing during emergency are given and discussed.

We assessed how self-motion affects the visual representation of the self. We constructed a novel virtual-reality experiment that systematically varied an avatar's motion and also biological sex. Participants were presented with pairs of avatars that visually represented the participant ('self-avatar'), or another person ('opposite avatar'). Avatar motion either corresponded with the participant's motion, or was decoupled from the participant's motion. The results show that participants identified with (i) 'self-avatars' over 'opposite-avatars', (ii) avatars moving congruently with self-motion over incongruent motion, and importantly (iii) with the 'opposite avatar' over the 'self-avatar' when the opposite avatar's motion was congruent with self-motion. Our results suggest that both self-motion and biological sex are relevant to the body schema and body image and that congruent bottom-up visual feedback of self-motion is particularly important for the sense of self and capable of overriding top-down self-identification factors such as biological sex.

Autism spectrum disorder (ASD) is characterized by atypical social communication and restricted and repetitive behaviors; such traits are continuously distributed across nonclinical and clinical populations. Recently, relationships between ASD traits and low-level multisensory processing have been investigated, because atypical sensory reactivity has been regarded as a diagnostic criterion of ASD. Studies regarding an audiovisual illusion (the double-flash illusion) reported that social communication difficulties are related to temporal aspects of audiovisual integration. This study investigated whether similar relationships exist in another audiovisual illusion (the stream-bounce effect). In this illusion, two visual objects move toward each other, coincide, and pass each other, and the presentation of a transient sound at their coincidence induces a dominant perception that they bounce away from each other. Typically developing adults were recruited to perform experimental trials involving the stream-bounce effect. We measured their ASD traits using the Autism-Spectrum Quotient. The total quotient score was not related to any behavioral measurements of the effect. In contrast, for participants with higher difficulty in communication, the greatest magnitude of the stream-bounce effect occurred when the presentation timing of the sound tended to follow the visual coincidence. Participants with higher difficulty in imagination also showed the greatest magnitude of the effect when the presentation timing of the sound preceded that of the visual coincidence. Our findings regarding the stream-bounce effect, along with previous findings regarding the double-flash illusion, suggest that atypical temporal audiovisual integration is uniquely related to ASD sub-traits, especially in social communication.

Experiments that focus on how humans perceive temporal, spatial or synaesthetic congruency in audiovisual sensory information have often employed stimuli consisting of a Gabor patch and an amplitude (AM) or frequency (FM)-modulated sound. Introducing similarity between the static and dynamic features of the Gabor patch and the (carrier) frequency or modulation frequency of the sound is often assumed to be effective enough to induce congruency. However, comparative empirical data on perceived congruency of various stimulus parameters are not readily available, and in particular with respect to sound modulation, it is still not clear which type (AM or FM) induces perceived congruency best in tandem with various patch parameters. In two experiments, we examined Gabor patches of various spatial frequencies with flickering (2, 3 and 4 flickers/s) or drifting (0.5, 1.0 and 1.5 degrees/s) gratings in combinations with AM or FM tones of 2-, 3- and 4-Hz modulation and 500-, 1000- and 2000-Hz carrier frequencies. Perceived congruency ratings were obtained by asking participants to rate stimulus (in)congruency from 1 (incongruent) to 7 (congruent). The data showed that varying the spatial frequency of the Gabor patch and the carrier frequency of the modulated tone had comparatively little impact on perceived congruency. Similar to previous findings, similarity between the temporal frequency of the Gabor patch and the modulated tone effectively promoted perceived congruency. Furthermore, direct comparisons convincingly showed that AM tones in combination with flickering Gabor patches received significantly higher audiovisual congruency ratings compared to FM tones.

We conducted two experiments to evaluate Meyerhoff and Scholl's (2018, Cognition 170, 88-94) hypothesis that illusory crescents contribute to resolutions in audiovisual stream/bounce displays. In Experiment 1, we measured illusory crescent size in the launching effect as a function of speed, overlap, and sound. In Experiment 2, we tabulated stream and bounce responses to similar stimuli with the same speed, sound, and overlap conditions as Experiment 1. Our critical manipulation of target speed spanned the range of values from typical stream/bounce investigations of ∼5 degrees/s up to the target speeds employed by Meyerhoff and Scholl ∼38 degrees/s. We replicated Meyerhoff and Scholl's findings at higher speeds, but not at slower speeds. Critically, we found that speed influenced crescent size judgements and bouncing responses in opposite directions. As target speed increased, illusory crescent size increased (Experiment 1), but the overall percentage of bounce responses decreased (Experiment 2). Additionally, we found that sound failed to enhance illusory crescent size at slower speeds but promotes bouncing responses at all speeds. The disassociation of the effects of speed and sound on illusory crescents with those effects on reported streaming/bouncing in similar displays provides compelling evidence against Meyerhoff and Scholl's hypothesis. Therefore, we conclude that illusory crescents do not account for the pattern of responses attributed to the stream/bounce effect.

There is a growing consensus that our most fundamental sense of self is structured by the ongoing integration of sensory and motor information related to our own body. Depersonalisation (DP) is an intriguing form of altered subjective experience in which people report feelings of unreality and detachment from their sense of self. The current study used the visual remapping of touch (VRT) paradigm to explore self-bias in visual-tactile integration in non-clinical participants reporting high and low levels of depersonalisation experiences. We found that the high-DP group showed an increased overall VRT effect but a no-self-face bias, instead showing a greater VRT effect when observing the face of another person. In addition, across all participants, self-bias was negatively predicted by the occurrence of anomalous body experiences. These results indicate disrupted integration of tactile and visual representations of the bodily self in those experiencing high levels of DP and provide greater understanding of how disruptions in multisensory perception of the self may underlie the phenomenology of depersonalisation.

Multisensory integration is a fundamental form of sensory processing that is involved in many everyday tasks. Those with Attention-Deficit/Hyperactivity Disorder (ADHD) have characteristic alterations to various brain regions that may influence multisensory processing. The overall aim of this work was to assess how adults with ADHD process audiovisual multisensory stimuli during a complex response time task. The paradigm used was a two-alternative forced-choice discrimination task paired with continuous 64-electrode electroencephalography, allowing for the measurement of response time and accuracy to auditory, visual, and audiovisual multisensory conditions. Analysis revealed that those with ADHD ( n = 10) respond faster than neurotypical controls ( n = 12) when presented with auditory, visual, and audiovisual multisensory conditions, while also having race model violation in early response latency quantiles. Adults with ADHD also had more prominent multisensory processing over parietal-occipital brain regions at early post-stimulus latencies, indicating that altered brain structure may have important outcomes for audiovisual multisensory processing. The present study is the first to assess how those with ADHD respond to multisensory conditions during a complex response time task, and demonstrates that adults with ADHD have unique multisensory processing when assessing both behavioral response time measures and neurological measures.

The last few years have seen an explosive growth of research interest in the crossmodal correspondences, the sometimes surprising associations that people experience between stimuli, attributes, or perceptual dimensions, such as between auditory pitch and visual size, or elevation. To date, the majority of this research has tended to focus on audiovisual correspondences. However, a variety of crossmodal correspondences have also been demonstrated with tactile stimuli, involving everything from felt shape to texture, and from weight through to temperature. In this review, I take a closer look at temperature-based correspondences. The empirical research not only supports the existence of robust crossmodal correspondences between temperature and colour (as captured by everyday phrases such as 'red hot') but also between temperature and auditory pitch. Importantly, such correspondences have (on occasion) been shown to influence everything from our thermal comfort in coloured environments through to our response to the thermal and chemical warmth associated with stimulation of the chemical senses, as when eating, drinking, and sniffing olfactory stimuli. Temperature-based correspondences are considered in terms of the four main classes of correspondence that have been identified to date, namely statistical, structural, semantic, and affective. The hope is that gaining a better understanding of temperature-based crossmodal correspondences may one day also potentially help in the design of more intuitive sensory-substitution devices, and support the delivery of immersive virtual and augmented reality experiences.