Table 1. fMRI hyperscanning.
| Authors | Neuroimaging methods | Subjects | Paradigms | Main discoveries |
|---|---|---|---|---|
| Montague et al., 2002, Neuoimage | Two 1.5 T fMRI | 3 pairs; gender: N/A; relationship: N/A | Game theory (a deceive game) | The very first hyperscanning study, where the term ‘hyperscanning’ was coined in this study |
| King-Casas et al., 2005, Science | Two 3 T fMRI | 48 pairs; gender: N/A; relationship: strangers | Game theory (trust game) | The study extends previous model-based fMRI studies into the social domain and broaden our view of the spectrum of functions implemented by the dorsal striatum |
| Fliessbach et al., 2007, Science | One 3 T fMRI, one 1.5 T fMRI | 19 pairs (5 subs were excluded); gender: all male; relationship: N/A | A simple estimation task that entailed monetary rewards for correct answers | A variation in the comparison subject’s payment affects BOLD responses in the ventral striatum |
| Krueger et al., 2007, PNAS | Two 3 T fMRI | 22 pairs; gender: 11 F-F; 11 M-M; relationship: strangers | Game theory (trust game) | The paracingulate cortex is critically involved in building a trust relationship by inferring another person’s intentions to predict subsequent behavior. Conditional trust selectively activated the ventral tegmental area, a region linked to the evaluation of expected and realized reward, whereas unconditional trust selectively activated the septal area, a region linked to social attachment behavior |
| Stolk et al., 2014, PNAS | One 3 T fMRI, one 1.5 T fMRI | 27 pairs; gender: all male; relationship: N/A | Cooperation task (jointly create a goal configuration of two geometrical tokens) | Establishing mutual understanding of novel signals synchronizes cerebral dynamics across communicators’ right temporal lobes |
| Spiegelhalder et al., 2014, BBR | Two 3 T fMRI | 11 pairs; gender: all female; relationship: good friends | Natural scenario (live dialog) | The time course of neural activity in areas associated with speech production was coupled with the time course of neural activity in the interlocutor’s auditory cortex |
| Koike et al., 2016, Neuroimage | Two 3 T fMRI | Gender: same gender; relationship: stranger; Exp. 1: 17 pairs (9 M-M;8 F-F); Exp. 2: 15 pairs (8 M-M;7 F-F); Exp. 3: 16 pairs (6 M-M;10 F-F) | Eye contact/gaze tasks (mutual gaze task: eye to eye) (joint attention task: eyes on other stuff together) | The right inferior frontal gyrus had been activated both by initiating and responding to joint attention |
| Shaw et al., 2018, Sci Rep | Two 3 T fMRI | 19 pairs; gender: all male; relationship: strangers | Game theory (ultimatum game) | Brain signals implicated in social decision making are modulated by the estimates of expected utility and become correlated more strongly between interacting players who reciprocate one another |
Main discoveries were directly extracted or adapted from the article’s abstracts, which is also applied to the Tables 2,3. The situation of subjects in fMRI hyperscanning is two subjects lying in fMRI tubes separately. PNAS, Proceedings of the National Academy of Sciences of the United States of America; BBR, Behavioural Brain Research; N/A, not available means the authors did not explicitly depict their subjects’ relationship or the exact numbers of gender pairs even though some studies addressed the overall numbers of genders.