title: Evidence of semantic clustering in letter-cued word retrieval.
abstract: Letter-cued word fluency is conceptualized as a phonemically guided word retrieval process. Accordingly, word clusters typically are defined solely by their phonemic similarity. We investigated semantic clustering in two letter-cued (P and S) word fluency task performances by 315 healthy adults, each for 1 min. Singular value decomposition (SVD) and generalized topological overlap measure (GTOM) were applied to verbal outputs to conservatively extract clusters of high-frequency words. The results generally confirmed phonemic clustering. However, we also found considerable semantic/associative clusters of words (e.g., pen, pencil, and paper), and some words showed both phonemic and semantic associations within a single cluster (e.g., pair, pear, peach). We conclude that letter-cued fluency is not necessarily a purely phonemic word retrieval process. Strong automatic semantic activation mechanisms play an important role in letter-cued lexical retrieval. Theoretical conceptualizations of the word retrieval process with phonemic cues may also need to be reexamined in light of these analyses.
authors.affiliation: a Department of Neurology , The Johns Hopkins University School of Medicine , Baltimore , MD , USA.
authors.forename: Kyongje
authors.initials: K
authors.lastname: Sung
authors.forename: Barry
authors.initials: B
authors.lastname: Gordon
authors.forename: Sujeong
authors.initials: S
authors.lastname: Yang
authors.forename: David J
authors.initials: DJ
authors.lastname: Schretlen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001245:Association Learning / Q000502:physiology*; D016000:Cluster Analysis; D003463:Cues; D005260:Female; D005793:Generalization, Psychological; D006801:Humans; D008297:Male; D011939:Mental Recall / Q000502:physiology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D012660:Semantics; D014705:Verbal Behavior / Q000502:physiology*; D014825:Vocabulary; D055815:Young Adult