Language Outcomes, Mechanisms, and Trajectories in Adults With and Without Developmental Language Disorder
University of Iowa
Summary
The investigators' overall objective is to characterize the long-term outcomes of Developmental Language Disorder (DLD) in adulthood and to identify specific cognitive mechanisms mediating these outcomes. To address their objectives, the investigators utilize a large, pre-existing dataset and participant pool from one of the most comprehensive examinations of DLD to date: the Iowa Longitudinal Study. The investigators will re-recruit subjects with DLD and with typical language from this historic cohort, who are now adults (30-35 years old). In Aim 1, the investigators will use measures from kindergarten through 10th grade and collect new outcome measures in adulthood to characterize the long-term outcomes of DLD. The investigators predict that adults with DLD will diverge from adults with TL in language skills that are more complex and higher-level language skills that are important for communication in the workplace. Further, the investigators predict a fanning effect: some children with DLD will "catch up" to their TL peers in adulthood, some will show evidence of a decline, and others will show stable trajectories. In Aim 2, the investigators measure real-time competition across written and spoken language using eye-tracking. According to speed of processing accounts adults with DLD may be slower than their TL peers to activate competitors and targets. According to working memory accounts adults with DLD will show sustained competitor activation. Further, the investigators predict that measures related to the dynamics of competition (speed of activation and timing of competitor suppression) will account for variation in language outcomes in adults.
Description
Aim 1: Characterize individual differences in the developmental trajectory and ultimate attainment of language ability in adults with and without DLD. This proposal directly addresses previous limitations by leveraging existing data and an existing participant pool from one of the most unique, influential, and comprehensive examinations of childhood DLD to date (the Iowa Longitudinal Study). The investigators re-recruit participants with and without DLD from this historic study who are now adults (30-35 years old). The investigators use retrospective oral language measures from kindergarten th…
Eligibility
- Age range
- 30–35 years
- Sex
- All
- Healthy volunteers
- Yes
Inclusion Criteria: * Adults with Developmental Language Disorder (DLD) and those with typical language (TL) between the ages of 28 and 40 years who participated in the Iowa Longitudinal Study(NIH-DC-19-90 \& P50 DC002746; IRB# 200106051, "Collaboration on Specific Language Impairment".) * Aged 30-35 * Normal or corrected to normal vision * Normal hearing Exclusion Criteria: * history of brain injury * history of neural developmental disabilities * not monolingual
Interventions
- BehavioralEye-Tracking in Visual World Paradigm
Participants complete six eye tracking tasks. They see images on a computer screen are tasked with finding a specific picture or saying a specific word (target). We track their eye movements to the visual representations of the target compared with their eye movements to visual representations of items that are similar to the target.
Location
- Wendell Johnson Speech and Hearing CenterIowa City, Iowa