Prism Adaptation and Optokinetic Stimulation Comparison in the Rehabilitation of Unilateral Spatial Neglect

Abstract

Prism adaptation (PA) is one of the most effective treatments for the rehabilitation of unilateral spatial neglect. Optokinetic stimulation (OKS) has also been demonstrated to be effective in ameliorating symptoms of neglect. The aim of this study is to compare the effectiveness of these two methods in a group of neglect patients using a crossover design. A group of 13 post-acute brain-damaged patients with unilateral spatial neglect, who had never been rehabilitated, were treated using PA and OKS. Each treatment was applied for 10 sessions, twice a day, to all patients with both treatments in crossed order (i.e., PA followed by OKS or vice versa). Neuropsychological assessments were performed: before the first (T1), at the end of the first/beginning of the second (T2) and at the end of the second training sessions (T3), and two weeks after the end of treatment (T4). Both procedures produced a significant improvement in clinical tests at T2, independent of the type of training. The results suggest that either PA or OKS induces a significant amelioration of neglect in right brain-damaged patients, mainly in the first block of treatment. Since no differences between treatments were found, they could be applied in clinical practice, according to the requirements of the individual patient.

Prism adaptation combined with eye movement training for unilateral spatial neglect after stroke: Study protocol for a single-blind prospective, randomized controlled trial

“…PA is a “bottom-up” approach ( 22 ), and it influences the level of sensory-motor through visuomotor adaptation to reduce symptoms of spatial neglect and, in particular, to improve spatial motor-intentional “aiming” deficits ( 23 ). PA was first proposed to treat patients with USN in 1998 ( 24 ), and a battery of studies has shown that PA improves not only the performance of patients with USN on neglect assessments ( 25 – 27 ) (e.g., BIT-C, CBS, and bell test) but also on neglect-related processes ( 15 , 28 – 30 ). In addition, the sensorimotor after-effects of PA extend to the cognitive domain of patients with USN, for example, in complex spatial cognitive tasks required in daily life (navigation and terrain memory) ( 31 ), simple sound source localization abilities ( 32 ), etc.…”