PT  - JOURNAL ARTICLE
AU  - Mareike Bacha-Trams
AU  - Enrico Glerean
AU  - Juha Lahnakoski
AU  - Elisa Ryyppö
AU  - Mikko Sams
AU  - Iiro P. Jääskeläinen
TI  - The human brain views selfish behaviour towards genetic vs. non-genetic sibling differently
AID  - 10.1101/112383
DP  - 2017 Jan 01
TA  - bioRxiv
PG  - 112383
4099  - http://biorxiv.org/content/early/2017/02/28/112383.short
4100  - http://biorxiv.org/content/early/2017/02/28/112383.full
AB  - Previous behavioural studies have shown that humans act more altruistically towards kin. Whether and how such kinship preference translates into differential neurocognitive evaluation of social interactions has remained an open question. Here, we investigated how the human brain is engaged when viewing a moral dilemma between genetic vs. non-genetic sisters. During functional magnetic resonance imaging, a movie depicting refusal of organ donation between two sisters was shown, with participants guided to believe the sisters were related either genetically or by adoption. The participants selfreported that genetic relationship was not relevant to them, yet their brain activity told a different story. When the participants believed that the sisters were genetically related, inter-subject similarity of brain activity was significantly stronger in areas supporting response-conflict resolution, emotion regulation, and self-referential social cognition. Our results show that mere knowledge of a genetic relationship between interacting persons can robustly modulate social cognition of the perceiver.