ABSTRACT Stuttering is a neurodevelopmental disorder associated with profound psychosocial consequences. Individuals who stutter commonly experience peer rejection, social isolation, and debilitating emotional responses to their stuttering. These hidden features of stuttering vary widely across individuals and are challenging to treat, but underlying causal mechanisms are not well-understood. The proposed project addresses this critical gap by focusing on attentional processes that may drive psychological responses to stuttering. The project draws upon the extensive literature on threat-related attention bias (AB), examining the extent to which such attentional patterns are associated with stuttering. Threat-related AB refers to preferential allocation of attention toward threatening stimuli and is a well-established finding in adults and children with clinical and subclinical anxiety. Cognitive models attribute AB to imbalances in early processes that detect threat, or late processes that modulate reactivity to threat, which manifest as faster detection of threat (vigilance), difficulty disengaging from threat (maintenance), threat avoidance, or combinations of these tendencies. AB may feed anxiety by promoting heightened sensitivity toward threat and hypervigilant scanning of environmental stimuli. Individuals who stutter show analogous anticipatory behaviors related to speaking, suggesting that similar AB patterns may underlie stuttering. The proposed project investigates threat-related AB in adults who do and do not stutter using a multi- paradigm approach that combines behavioral and eye-tracking indices of AB. The primary aim is to establish group differences in AB and identify the stage of processing at which differences emerge based on three widely- used tasks associated with different stages of information processing and AB tendencies (Aim 1). Aim 2 is to determine the extent to which threat-related AB in adults who stutter is general (consistent with anxiety) or disorder-specific (reflecting personal lived experiences of stuttering) by comparing three categories of threat stimuli representing increasing content specificity (general, stuttering-related, and personally-feared threat words). Aim 3 applies mediation analyses to examine the role of AB as a critical mediating factor between subject-level risk factors (related to temperament and attention control) and individual differences in stuttering outcomes (impact and anticipation). The project is innovative in that it applies novel conceptual and experimental approaches from AB research, uses eye-tracking methodologies that reveal dynamic attention patterns, and includes mediation analyses to clarify contributions of AB and related factors to stuttering outcomes. Results will increase our understanding of operative mechanisms shaping responses to stuttering and can provide a means to identify individuals most vulnerable to adverse stuttering impacts. The long-term goal of the project is to generate key data for future intervention studies designed to reverse AB through AB modification paradigms that train attention away from threat. The proposed research thus supports the mission of NIDCD by advancing our understanding of stuttering and providing a foundation for new approaches to its assessment and treatment.

PROJECT NARRATIVE Stuttering profoundly impacts quality of life, mental health, and social, educational, and occupational success for millions of Americans and approximately 55 million worldwide. The proposed research addresses this critical public health need by contributing fundamental knowledge about the role of attention in core emotional features of stuttering. Through a multi-paradigm approach that synthesizes behavioral and eye-tracking indices of attention bias, the project examines associations between threat-related patterns of attention allocation and stuttering, providing a foundation for the development of novel interventions designed to target emotional responses to stuttering by reshaping underlying attention patterns.