[Lost in translation-an investigation of listening effort and performance in cochlear implant users in first and foreign language settings].

Background and objective: Speech comprehension in a foreign language under noise conditions presents an increased cognitive demand. For multilingual patients with cochlear implants (PwCI), this poses a particular challenge, as audiological routine diagnostics are typically conducted in the language of the clinical environment. This study investigates speech understanding in noise as well as the subjectively perceived listening effort in PwCI compared to normal-hearing (NH) individuals under both native and nonnative language conditions.

Materials and methods: PwCI and NH completed the Oldenburg Sentence Test (OLSA) in both German and English. The SNR₅₀ and the subjectively perceived mental effort, measured using the Rating Scale Mental Effort (RSME), were assessed. In addition, the subjective language competence in English as a foreign language was collected using the Common European Framework of Reference for Languages (CEFR).

Results: A total of 28 individuals with German as a first language and English as a foreign language (14 PwCI, 14 NH) were included. Among PwCI, the German version of the OLSA was significantly more intelligible than the English version (p = 0.010), whereas no significant difference was found for NH between language conditions. Listening effort was significantly higher during the English version of the OLSA in both PwCI (p = 0.003) and NH (p = 0.003). No correlation was found between self-assessed English language proficiency and perceived effort in either group.

Conclusion: The significantly reduced performance of PwCI in their foreign language under noise conditions reflects the established finding that multilingual individuals experience greater difficulty understanding speech in noise. The additionally reduced automatization of linguistic processing as well as a limited use of top-down listening strategies, that is the use of prior knowledge, context and expectations to fill gaps in the acoustic signal, make understanding in the presence of background noise more difficult, which can lead to increased listening effort and more frequent comprehension gaps. These effects appear to be particularly pronounced in multilingual individuals. These results highlight the importance of individualized, linguistically and culturally sensitive approaches in the clinical management of PwCI.