Interoception and Empathy Impact Perspective Taking

Adopting the perspective of another person is an important aspect of social cognition and has been shown to depend on multisensory signals from one’s own body. Recent work suggests that interoceptive signals not only contribute to own-body perception and self-consciousness, but also to empathy. Here we investigated if social cognition – in particular adopting the perspective of another person – can be altered by a systematic manipulation of interoceptive cues and further, if this effect depends on empathic ability. The own-body transformation task (OBT) – wherein participants are instructed to imagine taking the perspective and position of a virtual body presented on a computer screen – offers an effective way to measure reaction time differences linked to the mental effort of taking an other’s perspective. Here, we adapted the OBT with the flashing of a silhouette surrounding the virtual body, either synchronously or asynchronously with the timing of participants’ heartbeats. We evaluated the impact of this cardio-visual synchrony on reaction times and accuracy rates in the OBT. Empathy was assessed with the empathy quotient (EQ) questionnaire. Based on previous work using the cardio-visual paradigm, we predicted that synchronous (vs. asynchronous) cardio-visual stimulation would increase self-identification with the virtual body and facilitate participants’ ability to adopt the virtual body’s perspective, thereby enhancing performance on the task, particularly in participants with higher empathy scores. We report that participants with high empathy showed significantly better performance during the OBT task during synchronous versus asynchronous cardio-visual stimulation. Moreover, we found a significant positive correlation between empathic ability and the synchrony effect (the difference in reaction times between the asynchronous and synchronous conditions). We conclude that synchronous cardio-visual stimulation between the participant’s body and a virtual body during an OBT task makes it easier to adopt the virtual body’s perspective, presumably based on multisensory integration processes. However, this effect depended on empathic ability, suggesting that empathy, interoception and social perspective taking are inherently linked.

The effects of ambient light on task switching depend on the chronotype

The aim of the present study was to investigate the synchrony effect between chronotype and time of day on task switching and vigilance, and the effect of high illuminance on the performance of two chronotypes at their non-optimal time. Four 46 minute sessions were administrated on separate days, the illuminance (200 vs. 1200 lx at eye level) and time of day (1.5 hours vs. 10.5 hours after waking up) were manipulated within participants. We found that high illuminance (1200 lx) significantly decreased the latency switch cost only for evening type independent of time of day, and there was a trend that low illuminance (200 lx) was better for morning type to decrease latency switch cost compared with evening type. The high illuminance could decrease the subjective sleepiness significantly for both chronotypes at the later part of the experiment. No synchrony effect on task switching and vigilance was found in the present study. The results suggested that the effect of ambient light on task switching was modulated by chronotype. Current study enriched the research on the effect of ambient light on task switching. When setting the optimal light environment, we should considerate the individual difference such as chronotype.

Speech perception in individuals with auditory dys-synchrony: effect of lengthening of voice onset time and burst duration of speech segments

Objective:The purpose of this study was to evaluate the effect of lengthening of voice onset time and burst duration of selected speech stimuli on perception by individuals with auditory dys-synchrony. This is the second of a series of articles reporting the effect of signal enhancing strategies on speech perception by such individuals.Methods:Two experiments were conducted: (1) assessment of the ‘just-noticeable difference' for voice onset time and burst duration of speech sounds; and (2) assessment of speech identification scores when speech sounds were modified by lengthening the voice onset time and the burst duration in units of one just-noticeable difference, both in isolation and in combination with each other plus transition duration modification.Results:Lengthening of voice onset time as well as burst duration improved perception of voicing. However, the effect of voice onset time modification was greater than that of burst duration modification. Although combined lengthening of voice onset time, burst duration and transition duration resulted in improved speech perception, the improvement was less than that due to lengthening of transition duration alone.Conclusion:These results suggest that innovative speech processing strategies that enhance temporal cues may benefit individuals with auditory dys-synchrony.

Influence of Circadian Typology and Time of Day on Temporal Preparation

The present study addressed the interactions between processes of circadian and millisecond timing by testing whether the ability for temporal preparation is influenced both by individual differences in circadian rhythmicity and by the time of day at which a task is performed. A temporal preparation task that measures temporal orienting and sequential effects was administered to morning-type and evening-type groups of participants, both in morning and evening sessions. The results confirmed a synchrony effect on overall reaction time (RT), indicating that participants were most vigilant at their optimal time of day according to their specific chronotype. This synchrony effect, however, did not influence temporal orienting or sequential effects. These findings suggest that only processes mediating overall RT (vigilance) but not processes related to temporal preparation are susceptible to circadian influence. The current research thus supports the dissociation between circadian timing and temporal preparation.