Face-to-face communication captured by fMRI

It’s tough to engage in face-to-face social interaction when you’re lying motionless in a magnet, but for the first time researchers have developed a way for fMRI study participants to do exactly that. This study, published in the April issue of NeuroImage (Vol. 50, No. 4), suggests that previous, indirect techniques may not have captured the full picture of social brain activation.

Scientists at the Massachusetts Institute of Technology rigged up a videoconferencing system that enabled participants to see and work with an experimenter to complete simple tasks. In one task, the experimenter moved her eyes to indicate where on her screen a wedge of cheese concealed a mouse, and the participant chose the correct cheese wedge by also looking in that direction. In another task, the participants indicated through the direction of their gazes which bucket they wanted the experimenter to pluck a toy from.

The procedure differs from past studies that simulated social interaction by having fMRI study participants play games with people lying in other rooms, receiving feedback indirectly, perhaps through a computer display or pre-recorded video.

“It seems that in live interactions, more regions may be recruited, and previously identified regions may be recruited to a greater extent,” says lead author Elizabeth Redcay, PhD, a postdoc in MIT’s brain and cognitive sciences department. The brain’s right superior temporal sulcus — an area that help us interpret others’ actions — was particularly active for participants as they interacted with an experimenter through the live video feed, Redcay found.

Future studies will be needed to pinpoint how these brain regions work together to process social information, says David M. Amodio, PhD, director of the New York University Social Neuroscience Laboratory and associate editor for the journal Social Neuroscience. However, the study demonstrates an exciting new technical breakthrough, he says.

—S. Dingfelder