Rehabilitation of reading and visual exploration in visual field disorders: transfer or specificity?

Abstract

Reading and visual exploration impairments in unilateral homonymous visual field disorders are frequent and disabling consequences of acquired brain injury. Compensatory therapies have been developed, which allow patients to regain sufficient reading and visual exploration performance through systematic oculomotor training. However, it is still unclear whether the reading and visual exploration impairments require specific compensatory training for their improvement. We present the first cross-over rehabilitation study to determine whether the training-related performance improvements are task-specific, or whether there is a transfer of training-related improvements between reading and visual exploration. We compared the therapeutic effects of compensatory oculomotor reading and visual exploration training in 36 patients with unilateral homonymous visual field loss in a cross-over design. In addition, we explored whether the training sequence determines the overall treatment outcome. Our findings demonstrate that the training-related improvements in reading and visual exploration are highly specific and task-dependent, and there was no effect of training sequence.

Efficacy and Feasibility of Home-Based Training for Individuals With Homonymous Visual Field Defects

“…This finding is of obvious practical relevance, but also of theoretical interest. While previous studies 22,28 demonstrated little transfer between reading and exploration (i.e.…”

“…Even the majority of computer-based training is either completed in clinic 16,17 or at home with therapist supervision 20,22,23 , although one recent study has demonstrated that a web-based reading training can increase reading speed in patients with right-sided HVFDs 27 . Whether it is the patient regards to exploration and reading 22,28 . Since these are two of the most frequently observed impairments in patients with HVFDs 4 it was decided that the training should incorporate elements tailored towards each skill.…”

Adaptation to poststroke visual field loss: A systematic review

“…The majority of studies relating to compensatory treatments are concerned with the improvement of eye movements and scanning into the affected field (Bergsma et al., 2011; Roth et al., 2009; Aimola et al., 2014; Hazelton, Pollock, Walsh, & Brady, 2015; Jacquin‐Courtois, Bays, Salemme, Leff, & Husain, 2013; Lane, Smith, Ellison, & Schenk, 2010; Pambakian, Mannan, Hodgson, & Kennard, 2004; Kerkhoff, Münssinger, & Meier, 1994; Mazer et al., 2003; Nelles et al., 2010; Taylor, Poland, Harrison, & Stephenson, 2011; Schuett, Heywood, Kentridge, Dauner, & Zihl, 2012), as well as increased saccadic movements into the affected field (Mannan, Pambakian, & Kennard, 2010; Lévy‐Bencheton et al., 2016; Kerkhoff, Münßinger, Eberle‐strauss, & Stögerer, 1992). A number of studies have specifically reported on subjective improvements in activities of daily living following compensatory therapy, such as improvements in mobility, reading, driving, and detection of obstacles (Bergsma et al., 2011; Ong et al., 2015; Keller & Lefin‐Rank, 2010; Aimola et al., 2014; Jacquin‐Courtois et al., 2013; Kerkhoff et al., 1994; Mazer et al., 2003; de Haan, Melis‐Dankers, Brouwer, Tucha, & Heutink, 2015; Hayes, Chen, Clarke, & Thompson, 2012; Nelles et al., 2001; Rowe, Conroy, et al., 2016).…”

Web-based therapy for hemianopic alexia is syndrome-specific

“…These methods almost certainly improve reading speeds by inducing changes in the patients’ eye movements. A variety of methods have been tried, from inducing small-field optokinetic nystagmus (OKN),9 15 16 19 to training of voluntary-induced eye movements 17 18 20 21. All training methods induce an improvement, via mass practice (many thousands of repetitions), in the pattern of small amplitude, horizontal reading saccades.…”

“…All training methods induce an improvement, via mass practice (many thousands of repetitions), in the pattern of small amplitude, horizontal reading saccades. Two studies have clearly shown that the nature of the eye movement practice is key,16 17 with the most impressive evidence coming from a cross-over study where hemianopic patients practised reading therapy in one block and visual exploration training in another. Both therapies worked in a highly specific and task-dependent way: reading speed improved in the reading therapy block, while visual search did not, and vice versa 17.…”