Journal of Child Psychology and Psychiatry | ACAMH Pediatric Journal | Wiley Online Library

Central to major depressive disorder (MDD) onset and maintenance is maladaptive self-focused attention, which can be reliably indexed by greater: (a) usage of first-person singular pronouns (e.g., I ) in natural language and (b) alpha oscillations in resting-state EEG. Integrating these largely parallel bodies of research, the present study sought to explicate the associations between, and prospective predictive utility of, linguistic and neural indicators of self-focused attention in adolescents with remitted MDD over 12 months. At baseline, 126 adolescents (ages 13–18) with ( n  = 66) and without ( n  = 60) remitted MDD completed resting-state EEG. Retrospective interviews determined the occurrence of major depressive episodes (MDEs) during the follow-up period. A total of ~2.3 million messages were passively acquired from adolescents' smartphones, on which the proportion of first-person singular pronouns was derived. During the 12 months, 29 (23.0%) participants developed an MDE (28 remitted MDD, 1 control). Cox regression showed that while greater usage of first-person singular pronouns prior to MDE increased the risk for MDE (hazard ratio [HR] = 2.02, p  < .001), greater resting-state alpha power at baseline decreased the risk for MDE (HR = 0.78, p  = .001). Moreover, greater alpha power predicted subsequent first-person singular pronoun usage ( β  = 0.17, p  = .004). Mediation analysis indicated a marginal suppression effect (bootstrapped indirect effect p  < .10), such that accounting for first-person singular pronoun usage amplified the association between alpha power and MDE risk. Findings highlight functionally distinct alpha mechanisms and provide support for smartphone-based first-person singular pronoun usage as a neurobehavioral risk factor and a potentially promising intervention target for adolescent MDD.