Face processing in the infant brain after pandemic lockdown

The role of visual experience in the development of face processing has
long been debated. We present a new angle on this question through a
serendipitous study that cannot easily be repeated. Infants viewed short
blocks of faces during fMRI in a repetition suppression task. The same
identity was presented multiple times in half of the blocks (Repeat
condition) and different identities were presented once each in the other
half (Novel condition). In adults, the fusiform face area (FFA) tends to
show greater neural activity for Novel vs. Repeat blocks in such designs,
suggesting that it can distinguish same vs. different face identities. As
part of an ongoing study, we collected data before the COVID-19 pandemic
and after an initial local lockdown was lifted. The resulting sample of 12
infants (9–24 months) was divided equally into pre-and post-lockdown
groups with matching ages and data quantity/quality. The groups had
strikingly different FFA responses: pre-lockdown infants showed repetition
suppression (Novel > Repeat), whereas post-lockdown infants showed
the opposite (Repeat > Novel), often referred to as repetition
enhancement. These findings provide speculative evidence that altered
visual experience during the lockdown, or other correlated environmental
changes, may have affected face processing in the infant brain.