Verbal fluency, clustering, and switching in patients with psychosis following traumatic brain injury (PFTBI). Issue 2 (30th June 2015)

• Record Type: Journal Article
• Authors: Batty, Rachel; Francis, Andrew; Thomas, Neil; Hopwood, Malcolm; Ponsford, Jennie; Johnston, Lisa; Rossell, Susan
• Is Part Of: Psychiatry research. Volume 227:Issue 2/3(2015)
• Page Start: 152
• Page End: 159
• Publication Date: 2015-06-30
• Subjects: Phonemic fluency -- Semantic fluency -- Neuropsychology -- Schizophrenia -- Head-injury -- Language.; Psychiatry -- Periodicals; Psychiatry -- periodicals; Psychiatrie -- Périodiques; 616.89
• DOI: 10.1016/j.psychres.2015.03.040
• Languages: English
• ISSNs: 0165-1781

Abstract

Abstract: Verbal fluency in patients with psychosis following traumatic brain injury (PFTBI) has been reported as comparable to healthy participants. This finding is counterintuitive given the prominent fluency impairments demonstrated post-traumatic brain injury (TBI) and in psychotic disorders, e.g. schizophrenia. We investigated phonemic (executive) fluency (3 letters: 'F' 'A' and 'S'), and semantic fluency (1 category: fruits and/or vegetables) in four matched groups; PFTBI ( N =10), TBI ( N =10), schizophrenia ( N =23), and healthy controls ( N =23). Words produced (minus perseverations and errors), and clustering and switching scores were compared for the two fluency types across the groups. The results confirmed that PFTBI patients do show impaired fluency, aligned with existing evidence in TBI and schizophrenia. PFTBI patients produced the least amount of words on the phonemic fluency ('A') trial and total score, and demonstrated reduced switching on both phonemic and semantic tasks. No significant differences in clustering performance were found. Importantly, the pattern of results suggested that PFTBI patients share deficits with their brain-injured (primarily executive), and psychotic (executive and semantic), counterparts, and that these are exacerbated by their dual-diagnosis. These findings add to a very limited literature by providing novel evidence of the nature of fluency impairments in dually-diagnosed PFTBI. Highlights: PFTBI patients show impaired executive and semantic fluency. PFTBI deficits appear to be shared with their brain-injured, and psychotic, counterparts. We are first to demonstrate the value of face-to-face assessments of PFTBI patients. We are first to match PFTBI cases with TBI and schizophrenia patient controls during recruitment. We are first to assess PFTBI and matched patient groups using a psychometrically sound battery.