December 2021, ScientificAmerican.com 23ADVANCES
Ryan McVay
Getty Images
HUMAN BEHAVIORLosing Contact
Gaze patterns reveal
an intriguing subtlety
in human communicationConversation goes far beyond talking. It
also involves, as Swedish author Annika Thor
has written, “eyes, smiles, the silences be
tween the words.” When those elements
hum along together, conversational partners
feel most deeply engaged and connected.
Like good conversationalists, Dart
mouth College neuroscientists have taken
that idea and carried it to new places. They
report some surprising findings on the inter
play between eye contact and how two
people synchronize neural activity while
talking. The researchers suggest, in a paper
published in the Proceedings of the National
Academy of Sciences USA, that being in tune
with a conversational partner is good—but
that occasionally falling out of sync might
be even better.
Maintaining eye contact has long been
thought to act as the glue that connects
two people in conversation. Its absence
can signal social dysfunction. Similarly, thegrowing study of neural synchrony has
largely focused on the way alignment in
individuals’ brain activity benefits the
social connection between them.
Earlier research by the Dartmouth lab
had showed that synchronized pupil dila
tion serves as a reliable indicator of shared
attention, which in turn marks greater
neural synchrony. In the new study, which
measured pupil dilation during unstruc
tured 10minute conversations, the
researchers found that the initial moment
of eye contact—rather than a sustained
period of locked gazes—marks a peak in
shared attention. Synchrony, in fact, drops
sharply just after you look into your inter
locutor’s eyes and begins to recover only
when you and that person look away from
each other. “Eye contact is not eliciting
synchrony; it’s disrupting it,” says Thalia
Wheatley, the paper’s senior author.
Why would this happen? Wheatley and
lead study author Sophie Wohltjen contend
that making and breaking eye contact ulti
mately propels the conversation forward.
“Perhaps what this is doing is allowing us
to break synchrony and move back into
our own heads so that we can bring forth
new and individual contributions to keep
the conversation going,” Wohltjen says.“It’s a fantastic study,” says psychiatrist
and social neuroscientist Leonhard Schil
bach of the Max Planck Institute of Psychia
try in Munich, who studies social interaction
but was not involved in the new research.
He applauds how the experiment was de
signed to replicate natural encounters and
focus on freeform conversation. The results
suggest, he says, that “interpersonal syn
chrony is an important aspect of social inter
actions but may not always be desirable.”
Thinking further about eye contact’s
function, the researchers examined past
studies on creativity—which pointed to
the constraints of too much synchrony. “If
people are trying to innovate in some way,
you don’t want people in lockstep with
each other,” Wheatley says. “You want
people to [say], ‘What if we did this? What
if we did that?’ You need people to be pro
viding their independent insights.”
Connections between gaze and synchro
ny might be relevant to research in autism
and other psychiatric conditions that involve
atypical interaction. The findings also help
explain frustrations over videoconferencing
platforms, on which real eye contact is near
ly impossible to make—or break—because
of the positioning of cameras and windows
on screens. — Lydia Denworth