PB10. Apraxic deficits in sub-acute right hemisphere stroke result from deficient allo-centric visuo-spatial processing. Issue 8 (August 2018)

• Record Type: Journal Article
• Authors: Ubben, S.D.; Fink, G.R.; Kaesberg, S.; Kalbe, E.; Kessler, J.; Vossel, S.; Weiss, P.H.
• Is Part Of: Clinical neurophysiology. Volume 129:Issue 8(2018:Aug.)
• Page Start: e58
• Page End: e59
• Publication Date: 2018-08
• Subjects: Neurophysiology -- Periodicals; Electroencephalography -- Periodicals; Electromyography -- Periodicals; Neurology -- Periodicals; 612.8
• DOI: 10.1016/j.clinph.2018.04.635
• Languages: English
• ISSNs: 1388-2457

Abstract

Abstract : While visuo-spatial deficits are well characterized cognitive sequelae of right hemisphere (RH) stroke, apraxic deficits in RH stroke remain poorly understood. Likewise, very little is known about the association between apraxic and visuo-spatial deficits in RH stroke or about the putative common or differential pathophysiology underlying these deficits. Therefore, we examined the behavioral and lesion patterns of apraxic deficits (pantomime of object use and bucco-facial imitation) and visuo-spatial deficits (line bisection and letter cancellation tasks) in 50 sub-acute RH stroke patients. Using principal component analysis (PCA), we characterized the relationship between the two deficits. We hypothesized that any interaction of these neuropsychological measures may be influenced by the demands of ego-centric/space-based and/or allo-centric/object-based processing. Contra-lesional visuo-spatial deficits were common in our clinically representative patient sample, affecting more than half of RH stroke patients. Furthermore, about one third of all patients demonstrated apraxic deficits. PCA revealed that pantomiming and the imitation of bucco-facial gestures loaded clearly on a first component (PCA1), while letter cancellation loaded heavily on a second component (PCA2). For line bisection, overall mean deviation loaded on PCA1, while the difference between the mean deviations in contra- versus ipsi-lesional space loaded on PCA2. These results propose that PCA1 represents allo-centric/object-based processing and PCA2 2 ego-centric/space-based processing. This interpretation was corroborated by the statistical lesion analyses with the component scores. Data suggest that apraxic pantomime and imitation deficits in RH stroke result, at least in part, from disturbed allo-centric/object-based processing.