Characterizing the attentional mechanism of multisensory synchronous stimulation to improve the rehabilitation of unilateral spatial neglect.

Stroke is a frequent and severe neurological condition that can lead to persistent problems. Patients can experience difficulties in moving their limbs or may experience trouble with their speech. In addition to these more salient problems, more subtle impairments in cognitive functions may also be present. For instance, some patients may have difficulties orienting their attention towards stimuli on one side of the environment. This condition is known as hemispatial neglect.

Accurate detection of this and other cognitive impairments due to stroke is important. However, in Flanders, no appropriate instruments were available to quickly assess cognitive impairments in stroke patients. For this reason, we adapted the English Oxford Cognitive Screen for the Dutch speaking language area. In Chapter 2, we present normative data of Flemish neurologically healthy individuals. These normative data allow clinicians to compare patients’ test scores to neurologically healthy individuals with a similar age.

In addition, there is much variability in the way in which clinical neuropsychologists assess hemispatial neglect. We showed that currently used summary measures of hemispatial neglect represent spatial and non-spatial impairments differently than the way in which these summary measures are currently interpreted (Chapter 3). In addition, we demonstrated that the way in which hemispatial neglect is typically diagnosed may lead to inflated false positive rates (Chapter 4).

In addition to reliable and valid diagnostic methods, there is also a need for effective rehabilitation methods. We explored the potential of multisensory stimuli and virtual reality. In Chapter 5, we show that neurologically healthy volunteers attend synchronous multisensory signals equally compared to asynchronous multisensory signals. In Chapters 6 until 9 we explored various aspects of using virtual reality for post-stroke rehabilitation. First, we investigated the extent to which the term “virtual reality” is used to refer to diverse technological systems and proposed a new categorization of these systems (Chapter 6). Second, we demonstrated that virtual reality can be safe to use with (vulnerable) older adults and that older adults are willing to use virtual reality (Chapter 7). In Chapter 8, we present the design and preliminary validation of a new virtual reality rehabilitation game for patients with hemispatial neglect. Last, we present the design of a clinical trial to evaluate the efficacy and feasibility of this new rehabilitation approach (Chapter 9).

In sum, this dissertation contributes to improved diagnostic methods for cognition after stroke and has provided a foundation for using virtual reality as a new rehabilitation method for hemispatial neglect.