Disentangling the neuroanatomical correlates of perseveration from unilateral spatial neglect

Issue title: Primary Progressive Aphasia and Post-Stroke Aphasia: Some Complementary Insights into Brain-Behavior Relationships/Hemispatial Neglect and Related Disorders

Article type: Research Article

Authors: Kleinman, Jonathan T.^; | DuBois, Jeffery C. | Newhart, Melissa | Hillis, Argye E.^{; ;}

Affiliations: Departments of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA | Physical Medicine and Rehabilitation, Johns Hopkins University School of Medicine, Baltimore, MD, USA | Department of Cognitive Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA | Stanford University School of Medicine, Stanford, CA, USA

Note: [] Corresponding author: Argye E. Hillis, MD, Department of Neurology, Meyer 6-113, Johns Hopkins Hospital, 600 North Wolfe Street, Baltimore, MD 21287, USA. Tel.: +1 410 614 2381; Fax: +1 410 955 0672; E-mail: argye@JHMI.edu

Abstract: Perseverative behavior, manifest as re-cancelling or re-visiting targets, is distinct from spatial neglect. Perseveration is thought to reflect frontal or parietal lobe dysfunction, but the neuroanatomical correlates remain poorly defined and the interplay between neglect and perseveration is incompletely understood. We enrolled 87 consecutive patients with diffusion-weighted, perfusion-weighted imaging, and spatial neglect testing within 24 hours of right hemisphere ischemic stroke. The degrees of spatial neglect and perseveration were analyzed. Perseveration was apparent in 46% (40/87) of the patients; 28% (24/87) showed perseveration only; 18% (16/87) showed both perseveration and neglect; and 3% (3/87) showed neglect only. Perseverative behaviors occur in an inverted "U" shape: little neglect was associated with few perseverations; moderate neglect with high perseverations; and in severe neglect targets may not enter consciousness and perseverative responses decrease. Brodmann areas of dysfunction, and the caudate and putament, were assessed and volumetrically measured. In this study, the caudate and putamen were not associated with perseveration. After controlling for neglect, and volume of dysfunctional tissue, only Brodmann area 46 was associated with perseveration. Our results further support the notion that perseveration and neglect are distinct entities; while they often co-occur, acute dorsolateral prefrontal cortex ischemia is associated with perseveration specifically.

Keywords: Perseveration, neglect, acute stroke, diffusion-weighted imaging, perfusion-weighted imaging

DOI: 10.3233/BEN-2012-110235

Journal: Behavioural Neurology, vol. 26, no. 1-2, pp. 131-138, 2013