Sustaining attention in visuomotor timing is associated with location-based binding.

Maintaining focus of attention over prolonged periods can be challenging, especially when the target stimulus is absent from the temporal sequence. Prior research has shown that a temporal attentional cue filling in the temporal blank can improve sustained attention: in a sustained visual attention task requiring synchronizing finger tapping with a temporally regular sequence composed of brief flash disks interleaved with blank periods, task performance was improved when a continuous fixation point that served as a temporal attentional cue was presented superimposed on the disk stimulus. To test the hypothesis that binding the temporal attentional cue with the target temporal sequence by spatial overlapping is crucial for enhancing sustained attention, the present study conducted a series of three experiments that deconstructed the bound connection between the cue and the sequence stimulus. In Experiment 1, the cue was placed above or below a flash disk. In Experiment 2, the cue was between two vertically arranged flash disks. In Experiment 3, the cue was in a flash ring. No significant effect of sustained attention improvement was found in any of the three experiments. Experiment 4 further replicated these null results and the previously observed effect of sustained attention improvement when the temporal cue was superimposed on the sequence stimulus. Our finding demonstrates that binding by spatial overlapping during the temporal blank when the sequence stimulus is absent is critical for enhancing sustained attention, which should be beneficial for improving performance across a broader range of tasks that require prolonged maintenance of attention.

Visual over auditory superiority in sensorimotor timing under optimized condition.

Auditory over visual advantage in temporal processing is generally appreciated, such as the well-established auditory superiority in sensorimotor timing. To test for a possible visual superiority in temporal processing, here, we present a data set composed of a large 60 subjects sample and a data set including eight smaller samples of approximately 15 subjects, showing that synchronization to a temporally regular sequence was more stable for a visual bouncing ball (VB) than for auditory tones (ATs). The results demonstrate that vision can be superior over audition in sensorimotor timing under optimized conditions, challenging the generally believed auditory superiority in temporal processing. In contrast to the auditory-specific biological substrates of timing in sensorimotor interaction, the present finding points to tight visual-motor cortical coupling in sensorimotor timing.

Sustained visual attention improves visuomotor timing.

Relative to audition, vision is considered much less trustworthy in sensorimotor timing such as synchronizing finger movements with a temporally regular sequence. Visuomotor timing requires maintaining attention over time, whereas the sustained visual attention may not be well held in conventional visuomotor timing task settings where flashing visual stimuli consisted of a briefly presented flash and a long blank period. In the present study, the potential attentional lapses in time due to the disappearance of the flash were carefully controlled in Experiment 1 by changing the color of the flash instead of its disappearance, or in Experiment 2 by adding an additional continuously presented fixation point serving as an external attentional cue when the flash disappeared. Improvement of visuomotor timing performance was found in both experiments. The finding suggests a role of enhanced sustained visual attention in improving visuomotor timing, by which vision could also be a trustworthy modality for processing temporal information in sensorimotor interactions.

Relative Contributions of the Speed Characteristic and Other Possible Ecological Factors in Synchronization to a Visual Beat Consisting of Periodically Moving Stimuli.

Daily music experience involves synchronizing movements in time with a perceived periodic beat. Contrary to the auditory-specific view of beat synchronization, synchronization to a visual beat composed of a periodically bouncing ball has been shown to be not less stable than synchronization to auditory beats. The ecological relevance of periodically moving visual stimuli is considered to be essential for such synchronization improvement. However, multiple factors could be associated with the ecological relevance and the relative contributions of the ecological factors to the synchronization improvement remain unclear. The present study investigated whether ecological factors other than a proposed critical factor, i.e., the speed characteristic, are required to account for the synchronization improvement of the bouncing ball. A periodically contracting ring that had the same speed characteristic as the periodically bouncing ball but lacked other possible ecological factors of the ball was designed. The results showed that synchronization was more stable for the bouncing ball than for the contracting ring, and this stability difference was larger in the difficult 300-ms than in the comfortable 600-ms inter-beat interval tapping condition. The finding suggests that ecological factors other than the speed characteristic are required to explain the synchronization improvement of periodically moving visual stimuli, particularly in difficult tapping conditions.

Brain Structural and Functional Substrates of Personal Distress in Empathy.

Empathy is the capacity to understand and experience the feeling state of others. While individuals attribute negative empathic responses to their own feelings, they would endure personal distress that can be harmful to social interaction. However, the neural mechanism of personal distress remains unclear. Here, we examined the neural substrates of personal distress by combining structural (Voxel-based morphometry (VBM)) and functional (resting-state functional connectivity (FC) analysis) MRI approaches in 53 college students (aged 19-26). A negative correlation was found between a trait measure of personal distress and gray matter (GM) volume in the dorsal medial prefrontal cortex (dmPFC). FC analyses with the dmPFC as a seed further revealed that the connectivity between the dmPFC and posterior insula was positively correlated with the personal distress, and the connectivities between the dmPFC and the anterior middle cingulate cortex, left lateral frontal cortex, and left inferior parietal gyrus were negatively correlated with the personal distress. Our results suggested that personal distress is underlain by neural substrates associated with both cognitive and affective mechanisms. Taken together, the structural and functional correlates of personal distress revealed in the present findings shed new light into the understanding of empathy.

Emotion Regulation and Complex Brain Networks: Association Between Expressive Suppression and Efficiency in the Fronto-Parietal Network and Default-Mode Network.

Emotion regulation (ER) refers to the "implementation of a conscious or non-conscious goal to start, stop or otherwise modulate the trajectory of an emotion" (Etkin et al., 2015). Whereas multiple brain areas have been found to be involved in ER, relatively little is known about whether and how ER is associated with the global functioning of brain networks. Recent advances in brain connectivity research using graph-theory based analysis have shown that the brain can be organized into complex networks composed of functionally or structurally connected brain areas. Global efficiency is one graphic metric indicating the efficiency of information exchange among brain areas and is utilized to measure global functioning of brain networks. The present study examined the relationship between trait measures of ER (expressive suppression (ES) and cognitive reappraisal (CR)) and global efficiency in resting-state functional brain networks (the whole brain network and ten predefined networks) using structural equation modeling (SEM). The results showed that ES was reliably associated with efficiency in the fronto-parietal network and default-mode network. The finding advances the understanding of neural substrates of ER, revealing the relationship between ES and efficient organization of brain networks.

Functional connectivity pattern underlies individual differences in independent self-construal.

Independent vs interdependent self-construal is a concept that reflects how people perceive the relationship between self and other people, which has been extensively examined across disciplines. However, little evidence on the whole-brain functional connectivity (FC) pattern of independent vs interdependent self-construal has been reported. Here, in a sample of 51 healthy participants, we used resting-state functional magnetic resonance imaging and voxel-based FC analysis (i.e. FC strength and seed-based FC) by measuring the temporal correlation of blood oxygen level-dependent signals between spatially separate brain regions to investigate the neural mechanism of independent vs interdependent self-construal. First, we found that FC strength of bilateral posterior cingulate cortex and precuneus, and left inferior frontal gyrus were positively correlated with the independent vs interdependent score. Seed-based FC analysis with these three regions as seeds revealed that, FC within default mode network and executive control network was positively correlated with the independent vs interdependent score. Negative correlation with independent vs interdependent score was shown in the connections between default mode network and executive control regions. Taking together, our results provide a comprehensive FC architecture of the independent vs interdependent self-construal and advance the understanding of the interplay between culture, mind and brain.