Breaking Down the Bilingual Cost in Speech Production

Area of Science:

• Psycholinguistics
• Cognitive Neuroscience
• Speech Production

Background:

• Bilingual individuals often exhibit performance differences compared to monolinguals in verbal tasks.
• The 'bilingual verbal cost' is a documented phenomenon, but its underlying mechanisms require further investigation.

Purpose of the Study:

• To investigate the bilingual verbal cost in a large-scale picture-naming study in Spanish.
• To explore the influence of participant characteristics and linguistic properties (lexical frequency, phonological similarity) on this cost.

Main Methods:

• Compared naming performance of Spanish-Catalan bilinguals (dominant and non-dominant languages) with Spanish monolinguals.
• Analyzed single trial naming latencies using linear mixed models, controlling for participant and item effects.
• Examined the roles of lexical frequency and cross-lingual phonological similarity.

Main Results:

• Decreasing lexical frequency increased naming latencies across all groups but did not fully explain the bilingual cost.
• The bilingual cost was eliminated when naming words with high phonological similarity across Spanish and Catalan.
• Low phonological similarity across translations exacerbated the bilingual cost in speech production.

Conclusions:

• Lexical frequency contributes to the bilingual cost, but phonological similarity across translations is a critical factor.
• High phonological similarity between translated words mitigates the bilingual verbal cost in speech production.
• Understanding cross-lingual phonological similarity is essential for models of bilingual speech production.