Implicitly tuned: The neural effects of social feedback on adolescent learning.

Adolescents are particularly tuned to social cues, but how does this sensitivity affect their learning? This study examined whether social feedback conveyed through human faces modulates implicit learning of auditory speech patterns. Magnetoencephalography (MEG) was used to assess neural measures of learning in response to auditory linguistic input as participants engaged in a computer-controlled guessing task and received incidental social feedback in the form of smiling (positive) or frowning (negative) faces. The results showed that smiling faces produced neural response patterns consistent with learning statistical regularities in left-hemisphere regions involved in social and language processing, including the amygdala, anterior auditory cortex, inferior frontal cortex, and insula, whereas no significant learning-related effect was observed in the right hemisphere. In contrast, negative social feedback (frowning faces) did not produce a significant learning-related effect in either hemisphere, indicating no reliable neural effect of learning under negative feedback. Direct comparisons for positive and negative feedback revealed that the neural effect of learning was significantly larger for positive than for negative feedback, with this effect remaining robust after correction for multiple comparisons in the left insula. These results occurred despite the visual cues being incidental and unrelated to the auditory input. Together, the findings suggest that incidental social feedback from human faces influences neural mechanisms of learning during adolescence.