Verbal Fluency (VF) task total scores are widely used in language attrition studies, but they do not provide insight into the processes underlying optimal performance. We analyse the efficacy of clustering (subcategories within a category) and switching (shifting between these subcategories) strategies in phonemic (PVF) and semantic (SVF) tasks. First, we focus on L1 Finnish and L2 English performance among attriters (N = 38). Our analyses suggest similar processes underlying performance in both languages. These processes seem to remain unaffected by immersion time in the L2 environment (LoR) and frequency of L1 use, highlighting the importance of including L2 data alongside comparisons to L1 monolingual populations to account for a broad bilingual effect in language attrition studies.

Second, we compare attriters’ and monolinguals’ (N = 50) performance in L1. Our findings suggest that attriters rely on clustering in PVF more systematically than monolinguals, and they struggle to initiate a search for a new subcategory or return to a previous category (switching) after depleting a cluster in PVF and SVF tasks. Thus, our analysis demonstrates a difference in processing strategies between the groups that could potentially contribute to similar total scores in PVF and lower total scores in the attriter group in SVF.