What do We Know About Semantic Verbal Fluency in Turkish?

The semantic (or categorical) verbal fluency test involves asking a participant to generate as many words from a given category as they can for 60-90 seconds. Previously, I have collaborated with colleagues with the aim of proposing simple automatic scoring methods for verbal fluency data. My PhD student Rabia Yasa Kostas, co-supervised by Sarah MacPherson, is working on developing such an automated scoring tool for Turkish.

As our first step, we wanted to see what data there is on Turkish, what metrics had been used, and whether there were any norms that our tool might draw on. This led us to perform a systematic review of what is known about semantic verbal fluency in Turkish, the protocol for which has been registered and is available from Prospero. It turns out that there is a lot more data than we originally thought, but most of it is in unpublished Turkish dissertations. We are about to finish the full text screening stage of the review, and hope to complete data extraction and write up before Christmas.

So far, almost all of the relevant papers that we have found report results from the classic Semantic Verbal Fluency design (name as many animals as you can in 60 seconds), and use word counts to score them, not analysis techniques that uncover potential internal structure, such as Troyer’s clustering and switching approach.

I will blog again once our analysis is complete – in the mean time, wish us luck as we delve into data extraction!

PDF of Powerpoint


R1: Semantic fluency as neuropsychological test

Cecato, J. F., Martinelli, J. E., Izbicki, R., Yassuda, M. S., & Aprahamian, I. (2015). A subtest analysis of the Montreal cognitive assessment (MoCA): Which subtests can best discriminate between healthy controls, mild cognitive impairment and Alzheimer’s disease? International Psychogeriatrics / IPA, 1–8. https://doi.org/10.1017/S1041610215001982

Mioshi, E., Dawson, K., Mitchell, J., Arnold, R., & Hodges, J. R. (2006). The Addenbrooke’s Cognitive Examination Revised (ACE-R): A brief cognitive test battery for dementia screening. Int J Geriatr Psychiatry21(11), 1078–1085. https://doi.org/10.1002/gps.1610

R2: Scoring Semantic Fluency

Mayr, U. (2002). On the dissociation between clustering and switching in verbal fluency: Comment on Troyer, Moscovitch, Winocur, Alexander and Stuss. Neuropsychologia40(5), 562–566. https://doi.org/10.1016/S0028-3932(01)00132-4

Troyer, A. K., Moscovitch, M., & Winocur, G. (1997). Clustering and switching as two components of verbal fluency: Evidence from younger and older healthy adults. Neuropsychology11(1), 138–146.

R3: norms for English

These are two of several papers that exist

Tombaugh, T. N., Kozak, J., & Rees, L. (1999). Normative data stratified by age and education for two measures of verbal fluency: FAS and animal naming. Archives of Clinical Neuropsychology14(2), 167–177. https://doi.org/10.1016/S0887-6177(97)00095-4

Troyer, A. K. (2000). Normative data for clustering and switching on verbal fluency tasks. Journal of Clinical and Experimental Neuropsychology22(3), 370–378. https://doi.org/10.1076/1380-3395(200006)22:3;1-V;FT370

R4: common tool in neuropsychological assessment for Turkish patients

This is evidenced by numerous dissertations; we give two examples here.

Kiliç, Muhsin Koray (2015). Panic disorder: Neurocognitive functions and impulsivity. Unpublished dissertation

Yazici, Melik (2019). Neuropsychological Evaluation of the Population of Eastern and South-Eastern Anatolia on Executive Functions and Complex Attention. Unpublished dissertation.

R5: normative studies

Şentürk, T. (2019). Turkish Normative Data Of Semantic And Phonemic Verbal Fluency Tests. Dokuz Eylul University. Unpublished Masters Thesis

Tuncer, A. M. (2012). VERBAL FLUENCY PERFORMANCE OF TURKISH SPEAKING ADULTS. Anadolu University. Unpublished PhD thesis

R6: bilingualism

Kastenbaum, J. G., Bedore, L. M., Peña, E. D., Sheng, L., Mavis, I., Sebastian-Vaytadden, R., … & Kiran, S. (2019). The influence of proficiency and language combination on bilingual lexical access. Bilingualism, 22(2), 300-330.

Nielsen, T. R., & Waldemar, G. (2016). Effects of literacy on semantic verbal fluency in an immigrant population. Aging, Neuropsychology, and Cognition, 23(5), 578-590.

Uysal, A. A., & Maviş, I. (2018). Assessing Executive Functions of Turkish-German Bilinguals, Turkish Speaking Children with S/LI and Turkish Speaking Monolingual Children. Int Arch Commun Disord, 1(008).