Systematic Review of Sensory Stimulation Programs in the Rehabilitation of Acquired Brain Injury

Abstract. Acquired Brain Injury (ABI) can lead to sensory deficits and compromise functionality. However, most studies have been focused on motor stimulation in stroke and traumatic brain injury (TBI). Sensory stimulation in stroke and mild/moderate TBI has received reduced interest. The main objective of this review is to know the methodological characteristics and effects of sensory programs in ABI. Studies with the purpose of testing the efficacy of those programs were identified through a literature search, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and the Cochrane Collaboration Guidelines. Twenty-three studies were included in this review. The results show that in most studies sensory stimulation started within 12 months after injury and there is no consensus regarding frequency, duration and number of sessions, duration of intervention, and instruments used to assess outcomes. Most programs involved unisensory stimulation, and vision was the predominant target. The most used methods were compensation and somatosensory discrimination training. Most studies used a pre- and post-intervention assessment, with few studies comprising follow-up assessment. Regarding the studies revised, the interventions with positive outcomes in ABI are: compensation, cognitive training, vestibular intervention, somatosensory discrimination training, proprioceptive stimulation with muscle vibration, and sustained attention training with olfactory stimulation. Available findings suggest that sensory stimulation has positive results with immediate and long-term improvements in sensory functioning. This review provides useful information to improve rehabilitation and to design future investigation.

Virtual reality in neurorehabilitation: a review of its effects on multiple cognitive domains

INTRODUCTION

Neurological diseases frequently cause adult-onset disability and have increased the demand for rehabilitative interventions. Neurorehabilitation has been progressively relying on computer-assisted programs and, more recently, on virtual reality (VR). Current reviews explore VR-based neurorehabilitation for assessing and treating the most common neurological pathologies. However, none of them explored specifically the impact of VR on multiple cognitive domains.

AREAS COVERED

The present work is a review of 6 years of literature (2015-2020) on VR in neurorehabilitation with the purpose of analyzing its effects on memory, attention, executive functions, language, and visuospatial ability.

EXPERT OPINION

Our review suggests that VR-based neurorehabilitation showed encouraging results for executive functions and visuospatial abilities particularly for both acute and neurodegenerative conditions. Conversely, memory, and attention outcomes are conflicting, and language did not show significant improvements following VR-based rehabilitation. Within five years, it is plausible that VR-based intervention would be provided in standalone and mobile-based platforms that won't need a PC to work, with reduced latency and improved user interaction.

Keeping an eye on visual search patterns in visuospatial neglect: A systematic review

Patients with visuospatial neglect exhibit a failure to detect, respond, or orient towards information located in the side of space opposite to their brain lesion. To extend our understanding of the underlying cognitive processes involved in neglect, some studies have used eye movement measurements to complement behavioural data. We provide a qualitative synthesis of studies that have used eye-tracking in patients with neglect, with a focus on highlighting the utility of examining eye movements and reporting what eye-tracking has revealed about visual search patterns in these patients. This systematic review includes twenty studies that met the eligibility criteria. We extracted information pertaining to patient characteristics (e.g., age, type of stroke, time since stroke), neglect test(s) used, type of stimuli (e.g., static, dynamic), eye-tracker specifications (e.g., temporal and spatial resolution), and eye movement measurements (e.g., saccade amplitude, fixation duration). Five key themes were identified. First, eye-tracking is a useful tool to complement pen-and-paper neglect tests. Second, the lateral asymmetrical bias in eye movement patterns observed during active exploration also occurred while at rest. Third, the lateral asymmetrical bias was evident not only in the horizontal plane but also in the vertical plane. Fourth, eye movement patterns were modulated by stimulus- and task-related factors (e.g., visual salience, local perceptual features, image content, stimulus duration, presence of distractors). Fifth, measuring eye movements in patients with neglect is useful for determining and understanding other cognitive impairments, such as spatial working memory. To develop a fuller, and a more accurate, picture of neglect, future research would benefit from eye movement measurements.

Distinguishing the tremor of Parkinson's disease from essential tremor: finger displacement

Although, the tremor of Parkinson's disease (PD) usually, but not always, differs from essential tremor (ET), there is no simple bedside test to distinguish PD from ET. We believe we have made such an observation. We studied 50 consecutive tremor-dominant PD patients (mean age: 63.4 years; mean disease duration: 4.9 years) and 35 consecutive ET patients (mean age: 64.1 years; mean disease duration: 12.5 years). Among PD patients, 31 had a bilateral tremor and among ET patients, 29 patients had a bilateral tremor. Patients sat opposite the examiner and pointed both index fingers at the examiner's index fingers. Then they closed their eyes. Within 15 s, one or rarely both of the patient's index fingers moved, was displaced, either upward or laterally. Finger displacement occurred only with bilateral simultaneous pointing with the patient's eyes closed. All the tremor-dominant PD patients exhibited displacement of an index finger. In 46 patients, it occurred on the side of dominant tremor, in 4, it occurred bilaterally. In 31 of 35 ET patients, no displacement occurred. In 4 of 35 ET patients, it occurred unilaterally on the side of dominant tremor. Odds ratio of distinguishing PD from ET: 89.62 at 95% confidence limits (5.31-1513.4), p = 0. 0018. Sensitivity 100% (0.91-1), specificity 89% (0.72-0.96). Finger displacement can distinguish the tremor of PD from ET. The unilateral movement with eyes closed suggests the tremor of PD unlike ET may impact circuits involving the parietal and supplementary motor cortices.