Mobile device use has become increasingly prevalent, yet its impact on infant development remains largely unknown. When parents use mobile devices in front of infants, the parent is physically present but most likely distracted and unresponsive. Research using the classic Still Face Paradigm (SFP) suggests that parental withdrawal and unresponsiveness may have negative consequences for children's social-emotional development. In the present study, 50 infants aged 7.20 to 23.60 months (M = 15.40, SD = 4.74) and their mothers completed a modified SFP. The SFP consisted of three phases: free play (FP; parent and infant play and interact), still face (SF; parent withdraws attention and becomes unresponsive), and reunion (RU; parent resumes normal interaction). The modified SFP incorporated mobile device use in the SF phase. Parents reported on their typical mobile device use and infant temperament. Consistent with the standard SFP, infants showed more negative affect and less positive affect during SF versus FP. Infants also showed more toy engagement and more engagement with mother during FP versus SF and RU. Infants showed the most social bids during SF and more room exploration in SF than RU. More frequent reported mobile device use was associated with less room exploration and positive affect during SF, and less recovery (i.e., engagement with mother, room exploration positive affect) during RU, even when controlling for individual differences in temperament. Findings suggest that the SFP represents a promising theoretical framework for understanding the impact of parent's mobile device use on infant social-emotional functioning and parent-infant interactions.

Anxiety-related attention bias (AB) has been studied for several decades as a clinically relevant output of the dynamic and complex threat-detection and -response system. Despite research enthusiasm for the construct of AB, current theories and measurement approaches cannot adequately account for the growing body of mixed, contradictory, and null findings. Drawing on clinical, neuroscience, and animal models, we argue that the apparent complexity and contradictions in the empirical literature can be attributed to the field’s failure to clearly conceptualize AB heterogeneity and the dearth of studies on AB that consider additional cognitive mechanisms in anxiety, particularly disruptions in threat-safety discrimination and cognitive control. We review existing research and propose a working model of AB heterogeneity, positing that AB may be best conceptualized as multiple subtypes of dysregulated processing of, and attention to, threat anchored in individual differences in threat-safety discrimination and cognitive control. We review evidence for this working model and discuss how it can be used to advance knowledge of AB mechanisms and inform personalized prevention and intervention approaches.