This paper examines switching and clustering in phonemic and semantic fluency tasks in individuals with traumatic brain injury (TBI). Fluency tasks were administered to 30 Hebrew-speaking patients with TBI and 30 age-matched control participants. Significant group differences were found in total output, number of switches, and number of clusters on both tasks, but not in mean cluster size. Unlike prediction, z scores of the number of semantic switches and clusters were lower than the equivalent z scores on the phonemic test. Results highlight the executive component of semantic fluency and the importance of using this task when assessing cognitive functioning after TBI.

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Neuropsychological tests are often used to evaluate executive function (EF) deficits in patients suffering traumatic brain injuries (TBIs). This study compared the sensitivity of three such tests--namely, the Delis-Kaplan Executive Function System Sorting Test (D-KEFS ST), the Wisconsin Card Sorting Test (WCST), and the Trail Making Test (TMT)--in differentiating between severe TBI patients and healthy controls. The differences between the two groups were significant for 5/5 variables evaluated through the D-KEFS ST, for 4/6 variables evaluated through the WCST, and for 2/2 variables evaluated through the TMT. Receiver operating characteristic analysis revealed that the variables "attempted sorts" in the D-KEFS ST and completion time in Part B of the TMT were the most powerful predictors of group assignment, with cutoff points of 9.5 sorts and 84.5 seconds, respectively. Our results highlight the possible value of the D-KEFS ST in the evaluation of postinjury EF deficits in TBI patients.

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Women with a past or present diagnosis of AN show difficulties in visuo-perceptual EF, whereas verbal EF seem to be preserved. There may be a dissociation between verbal and visuo-perceptual EF that persists after weight restoration.

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The span paradigm is commonly used to assess working memory (WM), predominantly through the visual and auditory routes and less often through the tactile modality. The current study aimed to validate the “Tactual Span”, a new task developed to evaluate WM in the tactile modality. Participants were 140 healthy young adults, who performed the Tactual Span alongside span tasks in three additional modalities (auditory, visual, and visuospatial), as well as a selective attention task and a semantic verbal fluency task. The Tactual Span and other span tasks were found to correlate, while correlations with the selective attention and semantic fluency tasks were largely nonsignificant, indicating good construct validity. Cronbach’s alpha for both stages as well as skewness and kurtosis were also adequate. An exploratory factor analysis for the forward stage showed that the Tactual Span and Visuospatial Span were loaded on one factor, whereas the Auditory and Visual Spans were loaded on another factor. In the backward stage, all span tasks were loaded on a single factor. The findings provide an initial indication that the Tactual Span task is a feasible and valid tool for assessing WM in the tactile modality.

Studies examining visuospatial working memory (WM) in individuals with congenital deafness have yielded inconsistent results, and tactile WM has rarely been examined. The current study examined WM span tasks in the two modalities among 20 individuals with congenital deafness and 20 participants with typical hearing. The congenital deafness group had longer forward and backward spans than typical hearing participants in a computerized Corsi block-tapping test (Visuospatial Span), whereas no such difference was found in the Tactual Span (tactile WM). In the congenital deafness group, age of sign language acquisition was not correlated with either condition of the visuospatial task, and Tactual and Visuospatial Spans scores were correlated in the backward but not the forward condition. The typical hearing group showed no correlation between the tasks. The findings suggest that early deafness leads to visuospatial but not tactile superiority in WM, specifically with respect to the storage component. More broadly, it appears that deafness-related compensation mechanisms in WM do not affect the other modalities in a uniform manner.