When attention falters: brain, breathing, and behavioral signals of lapses in interoceptive attention.

Mind body practices like meditation and yoga, which are widely used to support mental health, involve paying attention to internal bodily sensations like the breath. During these practices, individuals often report "interoceptive lapses," moments when attention drifts away from the body. While lapses in attention to the external world have been widely studied, far less is known about physiological and neural signals that temporally predict when attention to internal sensations falters. Interoceptive lapses may share markers with exteroceptive attention lapses-such as reaction time variability and changes in default-mode network (DMN) connectivity-but may also depend on distinct brain systems and breathing physiology. To test these possibilities, we examined behavioral, physiological and neural changes preceding lapses in a convenience sample of 93 adolescents with depressive symptoms. Participants performed a 20-minute breath counting task in the fMRI scanner with simultaneous breath recordings. Lapses were defined as moments when counting errors occurred. The sample was split into a training and validation sample, and machine learning models predicting attentional lapses were tested. The strongest predictors were timing and variability of button responses (AUCs > 0.75). Breathing variability and breathing-behavior coupling showed smaller but generalizable predictive value (AUCs < 0.65). Whole-brain connectivity models also predicted lapses (AUC ≈ 0.65) and incorporated regions within the DMN, dorsal, and ventral attention networks-overlapping with systems implicated in exteroceptive attention-as well as the somatomotor network. Further, models that included brain connectivity marginally outperformed behavior-only models. Together, these findings suggest that interoceptive lapses reflect both shared mechanisms with exteroceptive attention failures and additional contributions from brain systems involved in bodily representation and sensory pathways. Although generalizability is limited by the clinical sample and absence of an exteroceptive comparison task, these results highlight candidate brain-body markers of interoceptive attention that may inform real-time monitoring during mind-body interventions and improve understanding of interoceptive disturbance in affective disorders.