The use of pupillometry in bilingual language assessment (Pupil-BiLa)

• Applicant: Professorin Dr. Anna-Lena Scherger
• Subject Area: Applied Linguistics, Computational Linguistics
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 493770011

The increasing linguistic heterogeneity in everyday social life, schools and surgeries comes along with challenges for politics, the educational and health systems. This heterogeneity can be due to multilingualism but also due to language disorders. About 7% of all children exhibit a developmental language disorder (DLD). Recent research has shown that error patterns of healthy children growing up with two languages are similar to the ones of monolingual children with DLD. Consequently, when it comes to language diagnostics in bilingual children, it is difficult for pediatricians and language therapists to disentangle delays originating from the disorder and delays originating from bilingualism. There is a high rate of misdiagnoses in German bilingual children leading to a lack of treatment and to disadvantages for bilingual children concerning the start of school and further academic achievements. So far, bilingual diagnostics is based on the children’s language output (i.e. their production). However, for an appropriate treatment it is exceedingly important to diagnose children as early as possible before school starts. Usually, we are able to process and comprehend language before we produce it. Therefore, the present project idea focusses on the ability to process language by investigating an earlier stage in the language development than current approaches do. In addition, we implement a new technique into linguistic diagnostics, the so-called pupillometry. This methodology measures pupil sizes and dilations while the participant hears some auditory stimulus. Pupil dilations were recently used with monolingual infants as a marker of surprise, e.g. when hearing ungrammatical sentences. In the present project we aim at laying the foundations for a pupillometry-based diagnostic instrument in order to determine therapeutic need in bilingual children as early as possible. Therefore, bilingual children by the age of kindergarten entry will be investigated with respect to their ability to implicitly detect ungrammatical input after having heard 15 minutes of grammatical German input. The study design will be a combination of cross-sectional and longitudinal data collections in that the children’s further language development will be monitored and reassessed after 6, 12 and 24 months. By doing so, it will be backed up that those children who had not implicitly reacted on grammar violations at kindergarten entry are the ones that exhibit a DLD after 24 months in language production. Results shall serve as basic research in pupillometry-based diagnostics in order to avoid misdiagnoses and mistreatments in bilingual children.

• DFG Programme: Research Grants