Shared responses and individual differences in the human brain during naturalistic stimulations

The carefully designed experiments, delivered in a highly controlled way with brief, isolated, artificial stimuli and with sparse temporal order, have provided a fundamental understanding of the human brain. However, their ecological validity is debatable due to the far more complex and dynamic nature of real-life stimuli. Investigating the dynamic changes in brain activities, as well as other physiological responses, during a naturalistic environment may bridge this gap. Shared responses and individual differences have been captured during naturalistic contexts by various brain imaging and stimulation techniques (e.g., hyper scanning, multibrain stimulation) and analysis approaches (e.g., inter-subject correlation and variability, representation similarity). For example, subjects show synchronized brain activities when viewing the same movie, or engaging in social interactions. The deviated responses (individual differences) have been captured and used to identify the psychiatric mental status. Further, it was reported that synchronized eye movements predict test scores in online education. However, it’s not yet clear that to what extent the inter-brain synchrony and variability could be captured by these brain imaging and stimulation techniques and data analysis approaches, what is the causal relationship between the shared and deviated brain responses and behavioral similarity or variability, or how the deviated responses can be used for the psychiatric diagnosis.

This Research Topic aims to quantify the association between the shared experiences/viewpoints/traits among individuals with their shared brain responses to the naturalistic stimulations. We aim to treat the inter-subject variance in brain activities as valuable data that characterize individual differences, rather than noise as it has been reported that people with different psychiatric mental status, attitudes, political viewpoints can be successfully identified due to their idiosyncratic patterns of brain activity. We can use well-designed naturalistic stimulations to explore the boundary of shared responses; adopt brain stimulation or other intervention methods to quantify the causal relationship between response synchrony and shared experiences/viewpoints, and develop different algorithms to capture the shared responses and individual differences. The collection of these studies may promote the development of naturalistic imaging, psychiatric diagnosis, and individual differences characterizing.

Specifically, we aim to gather the studies using different naturalistic stimulations, measure different responses, and adopt different algorithms to enhance our understanding of shared responses and individual differences in a real-life context. Meanwhile, review articles and comments are also welcome in this research topic. Areas to be covered include, but are not limited to:
- Brain-to-brain group synchrony during naturalistic events.
- Brain stimulation to explore the causal relationship between inter-brain synchrony/variability and interpersonal similarity/differences.
- The relationship between synchronized brain activities with other biomarkers for shared responses including but not limited to physiological responses like skin conductance responses and eye movements, behavioral synchrony, group polarization, etc.
- Algorithms for characterizing the shared brain responses.
- Algorithms for characterizing the individual differences besides the shared brain responses.
- How the idiosyncratic patterns of brain activity characterize the individual differences in attitudes, personalities, and other psychological characters.
- Potential implications of shared responses and individual differences during naturalistic stimulation for the psychiatric diagnosis.