Treatments of unilateral neglect: a review

Computer-Assisted Rehabilitation Shows Greater Efficacy Than Traditional in Visuospatial Skills and Cognition in Neglect Patients

This study is crucial for improving unilateral spatial neglect (USN) treatments, focusing on comparing the effectiveness of computer-assisted cognitive rehabilitation (CACR) against conventional rehabilitation (CR) methods. It aimed to address a significant research gap and improve patient outcomes by evaluating the impact of CACR versus CR on visuospatial perception, visual field and attention, and visual memory in patients with USN. This study was a randomized controlled trial. Forty-five consecutive patients with USN from a university rehabilitation center were divided into two groups: 22 patients received CACR with Rehacom software, focusing on saccadic eye movement, visual field, and visual-motor coordination, while 23 underwent CR that combined hemispheric activation approach, mental imagery training, and vibration therapy. Assessments included the Motor-Free Visual Perception Test (MVPT), Line Bisection Test (LBT), Visual Span Test (VST), and Visual Recognition Test (VRT). The study employed ANCOVA and effect size calculations to evaluate the effectiveness of CACR compared to CR in treating patients with USN. Results indicated that CACR significantly outperformed CR in improving visuospatial perception, visual field, attention, and memory, showcasing its effectiveness in treating USN. These findings demonstrate the superiority of CACR over CR, particularly in enhancing visual memory and attention, as evidenced by the large effect size in VRT and moderate effects in LBT and VST. This suggests CACR's potential as a more effective approach for rehabilitation in patients with USN due to brain injuries.

Addressing ADL ability in people with poststroke cognitive impairments: A Danish survey of clinical practice

BACKGROUND

In Denmark, stroke represents a leading disability cause. While people with difficulties in performing activities of daily living (ADL) due to poststroke cognitive impairments are often referred to occupational therapy, limited knowledge is available on the nature of these services.

AIM/OBJECTIVE

To explore how Danish occupational therapists describe their practice when addressing decreased ADL ability in people with poststroke cognitive impairments in hospital and municipality settings.

MATERIAL AND METHODS

National, cross-sectorial, web-based public survey.

RESULTS

244 occupational therapists accessed the survey; 172 were included in the analysis. Most respondents could indicate the theory guiding their reasoning; half used standardised assessments. Regarding intervention, restorative and acquisitional models were preferred; specific strategies were identified. Intensity: 30-45 min 3-4 times/week in hospitals; 30-60 min 1-2 times/week in municipalities.

CONCLUSIONS

Therapists report to be guided by theory in their reasoning. Standardised assessments are used to a higher extend than previously reported. Still, the results invite critical reflections on correct use of assessment instruments, content and intensity of interventions, and how therapists keep themselves updated.

SIGNIFICANCE

The results document the need for practice improvements and may inform the definition of standard care in future trials.

Methodological comparison of cancellation versus two-way choice spatial attention tests in humans and dogs

Introduction

Behavioural problems in family dogs are amongst the leading reasons for relinquishment to shelters which adversely affects animal welfare. Recent research suggests that certain problematic behavioural patterns might be analogous to human psychiatric disorders. Veterinary diagnosis of such conditions, however, is scarce, probably due to the lack of appropriate measurement tools. The current study focuses on dog behaviour resembling the human hemispatial neglect condition, which manifests itself as a deficit in attention to and awareness of one side of the space.

Methods

Healthy human subjects (N = 21) and adult family dogs (N = 23) were tested with tools aimed to measure spatial attention. Tests administered to humans included validated paper and pencil neuropsychological tools to assess hemispatial neglect (cancellation tasks), as well as the canine version of that task (visuo-spatial search task). Dogs were tested with the same visuo-spatial search task as well as a two-way choice task.

Results

Results show that both in case of dogs and humans the visuo-spatial search task detects individual variation in subjects' side preferences. However, subjects' performance in the different tasks were not related.

Effect of stimulation-driven attention in virtual reality balloon search training of patients with left unilateral spatial neglect after stroke: A randomized crossover study

Patients with unilateral spatial neglect (USN) commonly experiences stimulus-driven attention deficit characterized by unexpected stimuli detection. We investigated whether virtual reality (VR) balloon search training with the screen background shifted to left space could improve stimulus-driven attention in patients with USN. The participants were divided into two groups: immediate VR group (n = 14) and delayed VR group (n = 14). The immediate VR group first received VR balloon search training, followed by control training, for two weeks each. Delayed VR group received the same training in reverse order. Outcomes were changes in scores on Catherine Bergego Scale (CBS) and reaction time on the modified Posner task (MPT). There was significant improvement in CBS score change after VR balloon retrieval training (all F > 2.71; P < 0.002). In the invalid condition of MPT, significant improvements were shown after VR balloon search training in left-sided reaction time (improvement of stimulation-driven attention). This study shows that VR balloon search training can improve neglect symptoms by using an intensive intervention lasting 2 weeks.

Effects of Twins Therapy on Egocentric and Allocentric Neglect in Stroke Patients: A Feasibility Study

(1) Background: Existing treatment methods for neglect are concentrated on egocentric neglect and may lead to various problems such as cost/space constraints and portability. Therefore, this study seeks to determine how a new treatment (also known as twins therapy, TT) for stroke patients can improve an existing problem associated with neglect. (2) Method: A pre/post-test control group research design was used and both groups continued to receive existing rehabilitation treatment, whilst TT intervention was only added to the experimental group. TT intervention was conducted for a total of 20 sessions (1 session for 30 min/day, 5 days/week, for 4 weeks). (3) Result: There was no significant difference in the manual function test (MFT) and the Korean version of the Modified Barthel Index (K-MBI) items (p > 0.05) before and after the TT intervention. However, the score and execution time of the apple cancellation test showed a significant reduction only in the experimental group (p < 0.05). (4) Conclusion: TT not only improved egocentric neglect, but also allocentric neglect symptoms in stroke patients.

Short- and Long-Term Effects of Repetitive Transcranial Magnetic Stimulation on Poststroke Visuospatial Neglect: A Systematic Review and Meta-analysis of Randomized Controlled Trials

OBJECTIVE

This systematic review and meta-analysis aimed to assess the effects of repetitive transcranial magnetic stimulation and select a suitable protocol for poststroke visuospatial neglect.

DESIGN

PubMed, Cochrane Library, and Embase databases were searched for relevant studies from the inception date to October 31, 2021. The inclusion criteria were (1) randomized controlled trials, (2) people with visuospatial neglect, (3) treatment with different repetitive transcranial magnetic stimulation protocols, (4) comparison with sham or blank control, and (5) reports of performance measurements.

RESULTS

Data were obtained from 11 randomized controlled trials. The effects of immediate and 1-mo postintervention were measured using line bisection test, cancellation test, and Catherine Bergego Scale. Results showed statistically significant improvement when applying low-frequency (0.5-1 Hz) repetitive transcranial magnetic stimulation or continuous theta burst stimulation to the left hemisphere on short- and long-term line bisection test (standardized mean difference = -1.10, 95% confidence interval = -1.84 to -0.37; standardized mean difference = -1.25, 95% confidence interval = -2.11 to -0.39) and cancellation test (standardized mean difference = 1.08, 95% confidence interval = 0.45 to 1.71; standardized mean difference = 1.45, 95% confidence interval = 0.42, 2.47).

CONCLUSIONS

Repetitive transcranial magnetic stimulation may be considered a treatment option for poststroke visuospatial neglect. This review proves that a decrease in neuronal excitation in the left hemisphere, which restores the interhemispheric balance, benefits poststroke visuospatial neglect.

Feasibility of hemispatial neglect rehabilitation with virtual reality-based visual exploration therapy among patients with stroke: randomised controlled trial

Background

Hemispatial neglect (HSN) was diagnosed using a virtual reality-based test (FOPR test) that explores the field of perception (FOP) and field of regard (FOR). Here, we developed virtual reality-visual exploration therapy (VR-VET) combining elements from the FOPR test and visual exploration therapy (VET) and examined its efficacy for HSN rehabilitation following stroke.

Methods

Eleven participants were randomly assigned to different groups, training with VR-VET first then waiting without VR-VET training (TW), or vice versa (WT). The TW group completed 20 sessions of a VR-VET program using a head-mounted display followed by 4 weeks of waiting, while the WT group completed the opposite regimen. Clinical HSN measurements [line bisection test (LBT), star cancellation test (SCT), Catherine Bergego Scale (CBS), CBS perceptual-attentional (CBS-PA), and CBS motor-explanatory (CBS-ME)] and FOPR tests [response time (RT), success rate (SR), and head movement (HM) for both FOP and FOR] were assessed by blinded face-to-face assessments.

Results

Five and six participants were allocated to the TW and WT groups, respectively, and no dropout occurred throughout the study. VR-VET considerably improved LBT scores, FOR variables (FOR-RT, FOR-SR), FOP-LEFT variables (FOP-LEFT-RT, FOP-LEFT-SR), and FOR-LEFT variables (FOR-LEFT-RT, FOR-LEFT-SR) compared to waiting without VR-VET. Additionally, VR-VET extensively improved FOP-SR, CBS, and CBS-PA, where waiting failed to make a significant change. The VR-VET made more improvements in the left hemispace than in the right hemispace in FOP-RT, FOP-SR, FOR-RT, and FOR-SR.

Conclusion

The observed improvements in clinical assessments and FOPR tests represent the translatability of these improvements to real-world function and the multi-dimensional effects of VR-VET training.

Clinical trial registration

https://clinicaltrials.gov/ct2/show/NCT03463122, identifier NCT03463122.

Assessment tools for differential diagnosis of neglect: Focusing on egocentric neglect and allocentric neglect

BACKGROUND

There are very few studies on the differential diagnosis between egocentric neglect (EN) and allocentric neglect (AN).

AIM

To investigate the overall trend of the previously developed assessment tools by conducting a descriptive review of the studies on assessment tools that can perform a differential diagnosis of EN and AN.

METHODS

The data were collected by using databases such as Google Scholar, PubMed, and ScienceDirect. The most commonly used search terms were “neglect”, “stroke”, “egocentric neglect”, and “allocentric neglect”.

RESULTS

A total of seven studies that met the inclusion criteria were selected and analyzed. We were able to confirm the research process, test method, and differential diagnosis criteria of the seven presented assessment tools from four studies on paper-based tests and three studies on computerized tests. The majority of the tests were carried out via the cancellation method using stimuli such as everyday objects or numbers. EN distinguished the left from right based on the test paper, while AN distinguished the left from right based on stimuli. In order to perform differential diagnosis, the difference in the number of left and right responses or non-responses was used based on the EN and AN criteria.

CONCLUSION

It was confirmed that all the seven assessment tools can effectively perform differential diagnosis of EN and AN. This study may provide important data that can be used in clinical practice for differential diagnosis and future intervention planning for neglect patients.

Rehabilitation interventions of unilateral spatial neglect based on the functional outcome measure: A systematic review and meta-analysis

ABSTRACTThis review aimed to examine the bottom-up and top-down rehabilitation intervention effectiveness based on the functional outcome measure as immediate effect and long-term effect for unilateral spatial neglect conditions. The RCT studies were collected by searching in three databases J-Stage, PubMed, and PEDro from 2008 through 2018. The studies which used the following instruments: BI, CBS, FMA, and FIM, as the functional outcome with the PEDro score of six and above, were eligible for inclusion. A total of 492 participants in 13 studies included from 291 studies initially identified. The meta-analysis for overall ES revealed that BI and CBS had a significant mean of SMD = 0.65 (95% CI, 0.23-1.07; p = 0.003; I2 = 65%), and SMD = -0.23 (95% CI, -0.45 to -0.01; p = 0.04; I2 = 35%) respectively, while FMA and FIM had an insignificant mean of SMD = 0.14 (95% CI, -0.08-0.37; p = 0.22; I2 = 0%), and SMD = -0.22 (95% CI, -0.69-0.25; p = 0.37; I2 = 0%) respectively. Based on the results, although indicated the heterogeneity representation across studies, it showed that the top-down intervention approach of high-frequency rTMS was more effective in enhancing the functional abilities and ADL of unilateral spatial neglect patients on the immediate effects but not necessarily in the long-term effects.

May I Smell Your Attention: Exploration of Smell and Sound for Visuospatial Attention in Virtual Reality

When interacting with technology, attention is mainly driven by audiovisual and increasingly haptic stimulation. Olfactory stimuli are widely neglected, although the sense of smell influences many of our daily life choices, affects our behavior, and can catch and direct our attention. In this study, we investigated the effect of smell and sound on visuospatial attention in a virtual environment. We implemented the Bells Test, an established neuropsychological test to assess attentional and visuospatial disorders, in virtual reality (VR). We conducted an experiment with 24 participants comparing the performance of users under three experimental conditions (smell, sound, and smell and sound). The results show that multisensory stimuli play a key role in driving the attention of the participants and highlight asymmetries in directing spatial attention. We discuss the relevance of the results within and beyond human-computer interaction (HCI), particularly with regard to the opportunity of using VR for rehabilitation and assessment procedures for patients with spatial attention deficits.

Effect of Prism Adaptation Therapy on the Activities of Daily Living and Awareness for Spatial Neglect: A Secondary Analysis of the Randomized, Controlled Trial

BACKGROUND

Rehabilitation for unilateral spatial neglect (USN) using prism adaptation (PA) is one of the most widely used methods, and the effectiveness of PA is well-evidenced. Although the effect of PA generalized various neglect symptoms, the effectiveness for some aspects of neglect is not fully proven. The Catherine Bergego Scale (CBS) was developed to identify problems with the activities of daily living (ADL) caused by USN. The CBS is composed of 10 observation assessments and a self-assessment questionnaire. To assess the self-awareness of USN, the anosognosia score is calculated as the difference between the observational scores and the self-assessment scores. To investigate how PA affects ADL and self-awareness in subacute USN patients during rehabilitation, we analyzed each item of the CBS and self-awareness from a randomized, controlled trial (RCT) that we previously conducted (Mizuno et al., 2011).

METHODS

A double-masked randomized, controlled trial was conducted to evaluate the effects of a 2-week PA therapy on USN in 8 hospitals in Japan. We compared each item of the CBS, anosognosia score, and absolute value of the anosognosia score between the prism group and the control group.

RESULTS

Two of ten items (gaze orientation and exploration of personal belongings) were significantly improved in the prism group compared with those in the control group. The absolute value of the anosognosia score was significantly improved by PA.

CONCLUSIONS

Improvement of oculomotor exploration by PA may generalize the behavioral level in a daily living environment. This study suggested that PA could accelerate the self-awareness of neglect during subacute rehabilitation.

The effects of robot-assisted left-hand training on hemispatial neglect in older patients with chronic stroke: A pilot and randomized controlled trial

BACKGROUND

Even though a variety of rehabilitative technique have been implemented to ameliorate neglect symptoms of patients with stoke, the effects of limb activation using a robotic device are still unknown. The purpose of this study was to investigate the effects of the robot-assisted hand training on hemispatial neglect of older patients with chronic stroke.

METHODS

The participants were randomly allocated to the experimental group (EG) receiving robot-assisted left-hand training (n = 12) or the control group (CG) receiving conventional treatments for neglect symptoms (n = 12). All participants received 20 sessions for 4-week. To examine the effects on hemispatial neglect, the line bisection test (LBT), the Albert test, and the Catherine Bergego Scale (CBS) were utilized. The outcome measures were analyzed before and after the 20 training sessions.

RESULTS

After the intervention, improvements in the LBT, the Albert test, and the CBS were found in the EG whereas there were significant improvements in the LBT and the CBS but not the Albert test in the CG. In addition, the EG showed a significantly greater gain in all outcome measures compared to the CG (p < .05).

CONCLUSIONS

These results indicate that robot-assisted hand training was beneficial to improving the hemispatial neglect of elderly person with chronic stroke compared to the conventional treatments. Robot-assisted limb activation might be useful to ameliorate hemispatial neglect of the elderly with chronic stroke.

Working Memory in Unilateral Spatial Neglect: Evidence for Impaired Binding of Object Identity and Object Location

Working memory (WM) is known to be impaired in patients with stroke experiencing unilateral spatial neglect (USN). Here, we examined in a systematic manner three WM components: memory of object identity, memory of object location, and binding between object identity and location. Moreover, we used two different retention intervals to isolate maintenance from other mnemonic and perceptual processes. Fourteen USN first-event stroke patients with right-hemisphere damage were tested in two different WM experiments using long and short retention intervals and an analog response scale. Patients exhibited more identification errors for items displayed on the contralesional side. Localization errors were also more prominent in the contralesional side, especially after a long retention interval. These localization errors were often a result of swap errors, that is, erroneous localizations of correctly identified contralesional objects in correctly memorized locations of ipsilesional objects. We conclude that a key WM deficit in USN is a lateralized impairment in binding between the identity of an object and its spatial tag.

Influence of right versus left unilateral spatial neglect on the functional recovery after rehabilitation in sub-acute stroke patients

Unilateral spatial neglect (USN) may lead to poor functional rehabilitation outcomes. However, studies investigating the rehabilitation outcomes of right-sided USN are lacking. We aimed to investigate (1) the clinical impacts of USN, including right-sided USN, for stroke patients in sub-acute rehabilitation, and (2) evaluate the differences in clinical characteristics and rehabilitation outcomes between right- and left-sided USN patients. We retrospectively screened the medical records of 297 inpatients at the Tokyo-Bay Rehabilitation Hospital who experienced a cerebrovascular accident with supratentorial lesions between January 1st, 2014 and December 31st, 2016. We performed independent multiple regression analysis in patients with left and right hemisphere damage. The Behavioral Inattention Test was a significant independent variable for predicting the motor, cognitive, and total functional independence measure (FIM), compared to the Stroke Impairment Assessment Set and Mini-Mental State Examination. USN affects motor FIM recovery more than cognitive FIM recovery regardless of the damaged hemisphere. Our study results confirm that both right- and left-sided USN influence the functional recovery of stroke patients. USN occurs, slightly less frequently, following a left hemisphere stroke. However, USN negatively affected rehabilitation outcomes, regardless of the neglected side. Therefore, USN treatment is necessary for patients with left and right hemisphere damage.

Reward sensitivity predicts dopaminergic response in spatial neglect

It has recently been revealed that spatial neglect can be modulated by motivational factors including anticipated monetary reward. A number of dopaminergic agents have been evaluated as treatments for neglect, but the results have been mixed, with no clear anatomical or cognitive predictors of dopaminergic responsiveness. Given that the effects of incentive motivation are mediated by dopaminergic pathways that are variably damaged in stroke, we tested the hypothesis that the modulatory influences of reward and dopaminergic drugs on neglect are themselves related. We employed a single-dose, double-blind, crossover design to compare the effects of Co-careldopa and placebo on a modified visual cancellation task in patients with neglect secondary to right hemisphere stroke. Whilst confirming that reward improved visual search in this group, we showed that dopaminergic stimulation only enhances visual search in the absence of reward. When patients were divided into REWARD-RESPONDERs and REWARD-NON-RESPONDERs, we found an interaction, such that only REWARD-NON-RESPONDERs showed a positive response to reward after receiving Co-careldopa, whereas REWARD-RESPONDERs were not influenced by drug. At a neuroanatomical level, responsiveness to incentive motivation was most associated with intact dorsal striatum. These findings suggest that dopaminergic modulation of neglect follows an 'inverted U' function, is dependent on integrity of the reward system, and can be measured as a behavioural response to anticipated reward.

Effect of Combined Therapy of Robot and Low-Frequency Repetitive Transcranial Magnetic Stimulation on Hemispatial Neglect in Stroke Patients

Objective

To investigate the effect of upper limb rehabilitation combining robot with low-frequency repetitive transcranial magnetic stimulation (rTMS) on unilateral spatial neglect in stroke patients.

Methods

Patients who had hemispatial neglect after right hemisphere stroke were randomly divided into rTMS only group, robot only group, and combined group. All groups received conventional neglect therapy and additional treatment for each group. rTMS group received rTMS therapy. Robot group received robot therapy, while combined group received both therapies. The effect of therapy was assessed with Motor-Free Visual Perception Test-3 (MVPT-3), line bisection test, star cancellation test, Catherine Bergego Scale (CBS), Mini-Mental State Examination (MMSE), and the Korean version of Modified Barthel Index (K-MBI). These measurements were evaluated before and after treatment.

Results

For each group, 10 patients were recruited. There were no significant differences in baseline characteristics or initial values among the three groups. Two weeks after the therapy, all groups showed significant improvement in MVPT-3, line bisection test, star cancellation test, CBS, MMSE, and K-MBI. However, changes in measurements showed no significant differences among groups.

Conclusion

Treatment effect of the combined therapy of robotic therapy and low-frequency rTMS therapy for hemispatial neglect was not statistically different from that of each single treatment.

Results

of this study did not prove the superiority of any of the three treatments. Further study with large number of patients is needed to evaluate the superiority of these treatments.

Use of virtual reality in improving poststroke neglect: Promising neuropsychological and neurophysiological findings from a case study

After experiencing a stroke in the right hemisphere, almost 50% of patients show unilateral spatial neglect (USN). Virtual Reality technologies offer impressive opportunities for both the rehabilitation and assessment of different cognitive deficits, including USN. A 57-year-old woman, affected by subarachnoid hemorrhage presented a severe left hemiparesis with severe cognitive and behavioral alterations, including temporal and spatial disorientation, reduction of attention and memory process, slowing ideation, USN, and depression of mood. She underwent two different rehabilitation trainings, including standard cognitive training (SCT) in addition to semi-immersive virtual training with her shadow (S-IVT_s) and SCT in addition to a Semi- immersive virtual training, without her shadow (S-IVT). The patient was assessed before and after each of the two different trainings, by using a specific psychometric battery and the event related potential, P300. Only at the end of the use of the S-IVT, we observed a significant improvement in the motor and cognitive function, with regard to USN. SCT in addition to S-IVT with Bts-Nirvana System may be a promising approach in improving attention process, spatial cognition, and mood in patients with post stroke USN, as also demonstrated by the electrophysiological parameters.

The Effect of an Upper Limb Rehabilitation Robot on Hemispatial Neglect in Stroke Patients

OBJECTIVE

To investigate the effectiveness of an upper limb rehabilitation robot therapy on hemispatial neglect in stroke patients.

METHODS

Patients were randomly divided into an upper limb rehabilitation robot treatment group (robot group) and a control group. The patients in the robot group received left upper limb training using an upper limb rehabilitation robot. The patients sat on the right side of the robot, so that the monitor of the robot was located on the patients' left side. In this position, patients could focus continuously on the left side. The control group received conventional neglect treatment, such as visual scanning training and range of motion exercises, administered by occupational therapists. Both groups received their respective therapies for 30 minutes a day, 5 days a week for 3 weeks. Several tests were used to evaluate treatment effects before and after the 3-week treatment.

RESULTS

In total, 38 patients (20 in the robot group and 18 in the control group) completed the study. After completion of the treatment sessions, both groups showed significant improvements in the Motor-Free Visual Perception Test 3rd edition (MVPT-3), the line bisection test, the star cancellation test, the Albert's test, the Catherine Bergego scale, the Mini-Mental State Examination and the Korean version of Modified Barthel Index. The changes in all measurements showed no significant differences between the two groups.

CONCLUSION

This present study showed that the upper limb robot treatment had benefits for hemispatial neglect in stroke patients that were similar to conventional neglect treatment. The upper limb robot treatment could be a therapeutic option in the treatment of hemispatial neglect after stroke.

The effect of voluntary trunk rotation and half-field eye-patching for patients with unilateral neglect in stroke: a randomized controlled trial

Objective : To investigate the effectiveness of voluntary trunk rotation and half-field eye-patching to treat patients with unilateral neglect in stroke.

Design : Pre—post, day 60 follow-up, single-blinded randomized controlled trial.

Setting : Single-centre inpatient rehabilitation hospital.

Subjects : Sixty subacute patients with right hemisphere stroke having unilateral neglect within eight weeks post stroke consented to participate between November 2003 and July 2005. They were randomly assigned to three comparison groups.

Interventions : Nineteen patients received daily experimental training in voluntary trunk rotation (TR) for 1 hour five times a week for 30 days. Twenty patients received the same kind of treatment together with half-field eye-patching

(TR + EP). Fifteen patients in the control group received conventional training with the same contact time.

Main outcome measures : Patients were assessed on days 0, 30 and 60 using the Behavioural Inattention Test, the Clock Drawing Test, and the Functional Independence Measure.

Results : No significant differences between voluntary trunk rotation (TR), voluntary trunk rotation and half-field eye-patching (TR + EP) and controls were found in functional performance and neglect measures at day 30 (P = 0.042—0.994) and follow-up (P = 0.052—0.911) at P = 0.005 using Bonferroni correction.

Conclusions : The results of this study do not support the use of voluntary trunk rotation alone or with half-field eye-patching to improve functional performance or reduce unilateral neglect in subacute patients with stroke.

Animal Models of Cerebral Neglect and Its Cancellation

The purpose of this perspective is twofold: 1) to alert and inform the neurospychology and neurology communities on how animal models can improve our understanding of spatial neglect in humans, and 2) to serve as a guide to rehabilitation strategies. Spatial neglect is a neurological syndrome that is inextricably linked to the ability to overtly or covertly reorient attention to new loci. Literature describing variants of neglect leads to the perception of lesion-induced neglect as a uniquely human syndrome for which there are limited treatment options. To the contrary, neglect has been reversed in laboratory animals, and results show that adequate neural representations and motor mechanisms for reversal are present despite damaged or deactivated cerebral cortex. These results and conclusions provoke thought on strategies that can be employed on humans to cancel neglect, and they suggest that long-term amelioration of neglect can be induced by training of specific bypass circuits.

The Effect of Transcranial Direct Current Stimulation on Neglect Syndrome in Stroke Patients

OBJECTIVE

To examine whether transcranial direct current stimulation (tDCS) applied over the posterior parietal cortex (PPC) improves visuospatial attention in stroke patients with left visuospatial neglect.

METHODS

Patients were randomly assigned to 1 of 3 treatment groups: anodal tDCS over the right PPC, cathodal tDCS over the left PPC, or sham tDCS. Each patient underwent 15 sessions of tDCS (5 sessions per week for 3 weeks; 2 mA for 30 minutes in each session). Outcome measures were assessed before treatment and 1 week after completing the treatment.

RESULTS

From pre- to post-treatment, there was an improvement in the motor-free visual perception test (MVPT), line bisection test (LBT), star cancellation test (SCT), Catherine Bergego Scale (CBS), Korean version of Modified Barthel Index (K-MBI), and Functional Ambulation Classification in all 3 groups. Improvements in the MVPT, SCT, and LBT were greater in the anodal and cathodal groups than in the sham group. However, improvements in other outcomes were not significantly different between the 3 groups, although there was a tendency for improved CBS or K-MBI scores in the anodal and cathodal groups, as compared with the sham group.

CONCLUSION

The study results indicated that the facilitatory effect of anodal tDCS applied over the right PPC, and the inhibitory effect of cathodal tDCS applied over the left PPC, improved symptoms of visuospatial neglect. Thus, tDCS could be a successful adjuvant therapeutic modality to recover neglect symptom, but this recovery might not lead to improvements in activities of daily living function and gait function.

Motor and Visuospatial Attention and Motor Planning After Stroke: Considerations for the Rehabilitation of Standing Balance and Gait

Attention and planning can be altered by stroke, which can influence motor performance. Although the influence of these factors on recovery from stroke has been explored for the upper extremity (UE), their impact on balance and gait are unknown. This perspective article presents evidence that altered motor and visuospatial attention influence motor planning of voluntary goal-directed movements poststroke, potentially affecting balance and gait. Additionally, specific strategies for rehabilitation of balance and gait poststroke in the presence of these factors are discussed. Visuospatial attention selects relevant sensory information and supports the preparation of responses to this information. Motor attentional impairments may produce difficulty with selecting appropriate motor feedback, potentially contributing to falls. An original theoretical model is presented for a network of brain regions supporting motor and visuospatial attention, as well as motor planning of voluntary movements. Stroke may influence this functional network both locally and distally, interfering with input or output of the anatomical or functional regions involved and affecting voluntary movements. Although there is limited research directly examining leg function, evidence suggests alterations in motor and visuospatial attention influence motor planning and have a direct impact on performance of gait and balance. This model warrants testing comparing healthy adults with individuals with stroke.

Effect of combination of transcranial direct current stimulation and feedback training on visuospatial neglect in patients with subacute stroke: a pilot randomized controlled trial

[Purpose] To investigate the effects of a combination of transcranial direct current stimulation (tDCS) and feedback training (FT) on subacute stroke patients with unilateral visuospatial neglect. [Subjects] The subjects were randomly assigned to a tDCS + FT group (n=6) and a FT group (n=6). [Methods] Patients in the tDCS + FT group received tDCS for 20 minutes and then received FT for 30 minutes a day, 5 days a week for 3 weeks. The control group received FT for 30 minutes a day, 5 days a week for 3 weeks. [Results] After the intervention, both groups showed significant improvements in the Motor-Free Visual Perception Test (MVPT), line bisection test (LBT), and modified Barthel index (MBI) over the baseline results. The comparison of the two groups after the intervention revealed that the rDCS + FT group showed more significant improvements in MVPT, LBT, and MBI. [Conclusion] The results of this study suggest that tDCS combined with FT has a positive effect on unilateral visuospatial neglect in patients with subacute stroke.

Assessment and rehabilitation of neglect using virtual reality: a systematic review

After experiencing a stroke in the right hemisphere, almost 50% of patients showed Unilateral Spatial Neglect (USN). In recent decades, Virtual Reality (VR) has been used as an effective tool both for the assessment and rehabilitation of USN. Indeed, this advanced technology allows post-stroke patients to interact with ecological and engaging environments similar to real ones, but in a safe and controlled way. To provide an overview of the most recent VR applications for the assessment and rehabilitation of USN, a systematic review has been carried out. Since 2010, 13 studies have proposed and tested innovative VR tools for USN. After a wide description of the selected studies, we discuss the main features of these VR tools in order to provide crucial indications for future studies, neurorehabilitation interventions, and clinical practice.

The effects of repetitive transcranial magnetic stimulation on unilateral neglect of acute stroke patients: A randomised controlled trial

Background

Rehabilitation of the unilateral neglect of acute stroke patients represents a major challenge.

Objectives

This study aimed to evaluate the effects of repetitive transcranial magnetic stimulation on the functional recovery of stroke patients with unilateral neglect.

Methods

Twenty patients with stroke were randomly assigned to two groups: a repetitive transcranial magnetic stimulation group (experimental) and a control group. The stroke patients in the experimental group underwent repetitive transcranial magnetic stimulation therapy and comprehensive rehabilitation therapy. The stroke patients in the control group underwent sham magnetic stimulation therapy and comprehensive rehabilitation therapy. The patients in both groups received therapy 5 days per week for 4 weeks. The Motor Free Visual Perception Test (MVPT), Line Bisection Test (LBT), Albert Test (AT), and Star Cancellation Test (SCT) were assessed before and after the 4-week therapy period.

Results

The experimental group showed a significant increase in the MVPT, LBT, AT, and SCT values compared with the preintervention values (p < 0.05). Furthermore, the control group showed a significant increase in the MVPT, LBT, and AT results compared with the preintervention results (p < 0.05). A significant difference in the post-training gains for the MVPT (8.9 ± 2.5 vs. 4.8 ± 3.0), LBT (-19.3 ± 7.5 vs. -6.5 ± 9.5), AT (13.1 ± 8.0 vs. 4.0 ± 1.9), and SCT (-13.6 ± 6.9 vs. -4.5 ± 6.9) were observed between the experimental group and the control group (p < 0.05). In addition, the effect size for gains in the experimental and control groups was very large in MVPT and AT (effect size = 3.25 and 2.90), respectively, and the effect size for gains in the experimental and control groups was small in LBT and SCT (effect size = 0.22 and 0.23, respectively).

Conclusion

The current study findings indicated that repetitive transcranial magnetic stimulation may be beneficial in decreasing the unilateral neglect of stroke patients.

Laterality of Motor Control Revisited: Directionality of Callosal Traffic and Its Rehabilitative Implications

Based on evidence derived from personal data and a comprehensive review of the literature, this article provides a perspective of laterality of motor control in humans. The evidence supports existence of directionality in callosal traffic, codified in handedness. However, it is the neural handedness that definitively reveals the directionality of signal traffic between the executive and the minor hemisphere; the minor hemisphere is devoted to the affairs occurring on or toward the nondominant side of the body. Thus, moving the nondominant side of the body (and sensing from it) are bi-hemispherical events that require callosal participation. Time-resolved data are provided that indicate the absence of any ipsilateral corticospinal tract innervation in humans. The rehabilitative aspects of the new circuitry (i.e., one-way callosal traffic scheme) is reviewed, establishing that previously described plasticity or reorganization of cortical structure was a reflection of the newly described anatomy underpinning handedness. The distinction between neural and behavioral handedness is emphasized, suggesting simple and robust ways to establish a person's handedness without resorting to invasive and inconclusive tests currently in vogue. In the past, lack of knowledge of directionality in callosal traffic has resulted in surgical removal of healthy hemispheres (including the major hemisphere) in futile attempts to stop epilepsy in those with an intractable condition. Evidence is provided for lack of any motor communication from the minor to the major hemisphere, which makes the minor hemisphere incapable of initiating and propagating seizures.

Evaluating Unilateral Spatial Neglect Post Stroke: Working Your Way Through the Maze of Assessment Choices

This study identified, using a comprehensive review of the literature, 62 standardized and nonstandardized assessment tools that exist to evaluate unilateral spatial neglect (USN). Each standardized tool was critically appraised according to its purpose (hemispace assessed), psychometric properties, and client appropriateness. The findings on the 28 standardized tools were compiled into a USN Assessment Summary Guide to facilitate clinical decision-making regarding the standardized USN assessments that are appropriate for specific clients at different phases of their recovery post stroke.

Effects of dual transcranial direct current stimulation on post-stroke unilateral visuospatial neglect

Based on the interhemispheric inhibition model of unilateral visuospatial neglect (USN) after stroke, the effects of dual-mode transcranial direct current stimulation (tDCS) over the parietal cortices were assessed in a double-blind random-order cross-over experiment. Ten chronic right hemispheric stroke patients (4 men; mean age: 62.6 years) with USN were recruited. All participants underwent three randomly arranged tDCS sessions: (1) dual-mode, anodal tDCS over the right posterior parietal cortex (PPC) and cathodal tDCS over the left PPC; (2) single-mode, anodal tDCS over the right PPC; and (3) sham mode. Each session lasted 20min. Before and immediately after the stimulation, a line bisection test and star cancelation test were carried out. In the line bisection test, significant improvements were observed after both the dual- and the single-mode tDCS (p<0.05), but not after sham stimulation. Statistical analysis showed a significant interaction between time and tDCS mode, where the dual tDCS had a stronger effect than the single or sham stimulation modes (p<0.05). The star cancelation test did not show any significant change. These results suggest that dual tDCS over the bilateral PPC is an effective method for the treatment of USN in stroke patients.

Effect of eye patching in rehabilitation of hemispatial neglect

Eye patching (EP; monocular or right hemifield) has been proposed to improve visuospatial attention to the ignored field in patients with hemispatial neglect. The aim of this paper is to review the literature on the effects of EP in hemispatial neglect after stroke in order to convey evidence-based recommendations to clinicians in stroke rehabilitation. Thirteen intervention studies were selected from the Medline, EMBASE, Scopus, Cochrane Library, CINAHL, PsychINFO, EBRSR, and Health Star databases. Methodological quality was defined according to the Physiotherapy Evidence Database. Overall, seven studies used monocular EP, five used right hemifield patching, and one compared right monocular with right hemifield patching. Seven studies compared normal viewing to monocular or hemifield patching conditions. Six studies included a period of treatment. As to the monocular EP, four studies reported positive effects of right monocular patching. One study showed an improvement in hemispatial neglect with left monocular patching. Two studies found no superiority of right vs. left monocular patching. One study found no effects of right monocular patching. As to the right hemifield EP, one study showed improvements in neglect after right hemifield patching. Three studies found that right hemifield patching combined with another rehabilitation technique was more effective than that treatment alone. One study found no differences between right hemifield patching combined with another treatment and that treatment alone. One study found the same effect between right hemifield patching alone and another rehabilitation technique. Our results globally tend to support the usefulness of right hemifield EP in clinical practice. In order to define a level of evidence with the standard rehabilitation evidence rating tools, further properly powered randomized controlled trials or meta-analysis are needed.

Anatomy of handedness and the laterality of seizure onset: surgical implications of new understandings in motor control

OBJECTIVES

This article pursues another corollary of the anatomy of handedness, a code for the laterality of motor control. The latter indicates the absence of any motor communication from the minor (right, in the vast majority of population) to the major hemisphere (left, in the vast majority of right handers). It also indicates that all communications between the two hemispheres are excitatory in nature. This arrangement prohibits initiation of seizure within the minor and its propagation to the major hemisphere, via the callosum.

METHODS

A comprehensive review of the literature is undertaken regarding theoretical and technical reasons for the failure of seizure surgery in subjects undergoing the same for intractable epilepsy.

RESULTS

Whereas the laterality of motor control is heavily biased towards the left hemisphere (approximately 80%), the operation is performed equally on both hemispheres. Failures of surgery in some series were substantially higher among those who had undergone operations on the right hemisphere. Technical reasons for this are traced to the unreliability of tests commonly employed in securing laterality of seizure onset, which is the same as that of motor control. Accordingly, the failure rate of seizure surgery may equal the rate of false lateralization of the major hemisphere in these circumstances.

CONCLUSION

Given the dichotomous anatomy of handedness, the most robust test for lateralizing the hemisphere of onset of seizure is that of determining the reaction times of two symmetrically located effectors, one on each side of the body. The side with the shorter reaction time will always be opposite to the major hemisphere. The difference between the two values is commensurate to the inter-hemispheric transfer time.

Rehabilitation Interventions for Unilateral Neglect after Stroke: A Systematic Review from 1997 through 2012

A systematic review of the effectiveness of rehabilitation for persons with unilateral neglect (UN) after stroke was conducted by searching the computerized databases from 1997 through 2012. Randomized controlled trials (RCTs) of neglect treatment strategies for stroke patients which used the Behavioral Inattention Test (BIT) as the primary outcome measure were eligible for inclusion. Out of 201 studies initially identified, 12 RCTs covering 277 participants were selected for analysis. All had the same weakness of low power with smaller samples and limitation in the blinding of the design. Prism Adaptation (PA) was the most commonly used intervention while continuous Theta-burst stimulation (cTBS) appeared to be a new approach. Meta-analysis showed that for immediate effects, the BIT conventional subscore had a significant and large mean effect size (ES = 0.76; 95% CI 0.28-1.23; p = 0.002) whereas the BIT total score showed a modestly significant mean ES (ES = 0.55; 95% CI 0.16-0.94; p = 0.006). No significant mean ES in sensitivity analysis was found for long-lasting effects across all BIT outcomes. PA appeared to be the most effective intervention based on the results of pooled analysis. More rigorous studies should be done on repetitive transcranial magnetic stimulation (rTMS) before it can be concluded that it is a promising treatment for UN.

Combined effects of sensory cueing and limb activation on unilateral neglect in subacute left hemiplegic stroke patients: a randomized controlled pilot study

Objective:

To compare the effects of contralesional sensory cueing and limb activation with that of sham control in the treatment of unilateral neglect after stroke.

Design:

A randomized, single-blinded, sham-controlled pilot study.

Setting:

Two rehabilitation hospitals.

Subjects:

Forty subacute left hemiplegic stroke inpatients with unilateral neglect.

Interventions:

Participants were assigned randomly to 1 of 2 groups. The experimental group wore a wristwatch cueing device over the hemiplegic arm for three hours a day, five days per week, for three weeks, and also underwent conventional rehabilitation. Patients were encouraged to move their hemiplegic arm five consecutive times after each prompt. The sham group underwent the same rehabilitation process, except they wore a sham device.

Main measures:

Neglect, arm motor performance, and overall functioning were assessed pre- and posttraining, and at follow-up.

Results:

There were no significant differences between groups in outcome measures except the neglect drawing tasks ( p = 0.034) (the mean gain score from baseline to follow-up assessment was 5.2 (3.7) in the experimental group and 1.9 (3.5) in the sham group), across three time intervals. The experimental group showed greater improvement in arm motor performance than did the sham group.

Conclusion:

The results did not confirm that sensory cueing and limb activation treatment is effective when compared with those receiving placebo to reduce unilateral neglect, but it might be useful for promoting hemiplegic arm performance in stroke patients.

Rehabilitation of spatial neglect

Spatial neglect is a frequent cause of disability associated with high costs and duration of hospital stay, increased family burden, and requirements for skilled chronic care. This condition is disproportionately more frequent with right than left hemispheric injury and it is characterized by perceptual, representational, and behavioral deficits involving or directed towards the left hemispace or the left hemibody. Spatial dysfunction is conceptualized into two major components: the perceptual/representational "where" component that results mainly from injury to posterior brain regions and the premotor/intentional "aiming" component that results mostly from damage to anterior brain regions. Additionally, deficits in arousal, vigilance, affective symptoms, and disorders of emotional communication may compound the clinical manifestations of spatial neglect. Evidence-based sources that evaluate the effectiveness of rehabilitation treatments for neglect are, unfortunately, unable to provide a unified consensus for the efficacy of a given treatment approach. The reasons for this failure are related to internal inconsistencies defining appropriate criteria for treatment success and lack of characterization of neglect mechanisms and considerations of patient characteristics related to treatment failure. In this chapter we advocate the use of visual scanning, limb activation therapy, and "general treatment" because we believe that they are appropriately supported by different sources and they may be useful for experimental trials and standardized clinical care. We advocate an integrative approach that takes advantage of the same rehabilitation strategy or task to treat different perceptual, representational, and premotor components of neglect. A variety of therapies that may be familiar to the rehabilitation team may be useful as long as they are applied in a systematized program and are based on good clinical judgment. Information regarding adjuvant pharmacological therapy is sparse but different agents with aminergic and cholinergic activity may be useful. Medication with sedative, antidopaminergic or anticholinergic properties may interfere with the rehabilitation process and should be avoided.

Multi-input/output alarming system for patients with inattention caused by higher cortical function disorder

Background

Method

Results

Conclusion

Long-term efficacy of prism adaptation on spatial neglect: preliminary results on different spatial components

This study describes the long-term effectiveness on spatial neglect recovery of a 2-week treatment based on prism adaptation (PA). Seven right-brain-damaged patients affected by chronic neglect were evaluated before, after two weeks of the PA treatment and at a follow-up (variable between 8 and 30 months after the end of PA). Neglect evaluation was performed by means of BIT (conventional and behavioral), Fluff Test, and Comb and Razor Test. The results highlight an improvement, after the PA training, in both tasks performed using the hand trained in PA treatment and in behavioral tasks not requiring a manual motor response. Such effects extend, even if not significantly, to all BIT subtests. These results support previous findings, showing that PA improves neglect also on imagery tasks with no manual component, and provide further evidence for long-lasting efficacy of PA training. Dissociations have been found with regard to PA efficacy on peripersonal, personal, and representational neglect, visuospatial agraphia and neglect dyslexia. In particular, we found no significant differences between the pre-training and post-training PA session in personal neglect measures, and a poor recovery of neglect dyslexia after PA treatment. The recruitment of a larger sample could help to confirm the effectiveness of the prismatic lenses with regard to the different clinical manifestations of spatial neglect.

Superior colliculi involvement in poststroke unilateral spatial neglect: a pilot study

PURPOSE

The neural mechanisms underlying unilateral spatial neglect (USN) are unclear. The superior colliculi (SC) may be involved in USN expression, and the spatial summation effect (SSE), where reaction times to bilateral stimuli are faster than to unilateral, may be a behavioral index of SC function. We determined the feasibility of investigating SC contribution to poststroke USN using the SSE in 3 groups.

METHODS

Seven participants with left near-extrapersonal space USN (USN+) following right hemisphere stroke, 10 without (USN-), and 10 controls were tested under binocular/monocular (right eye patched) conditions while responding to unilateral/bilateral stimuli. Control and USN- groups completed the SSE paradigm.

RESULTS

Most USN+ participants were unable to initiate the SSE paradigm due to poor visual fi xation and demonstrated higher contrast sensitivity for left-sided stimuli. Controls showed an SSE (under both viewing conditions) while the USN- showed an abnormal SSE whereby reaction times to bilateral stimuli were faster than to unilateral-left but not to unilateral-right stimuli (under both binocular/monocular conditions).

CONCLUSION

This study is the fi rst to investigate SC contribution in poststroke USN using the SSE; we identifi ed higher contrast sensitivity to left-sided stimuli and poor fi xation in the USN+ group. These fi ndings suggest avenues for research that may lead to novel rehabilitation interventions.

The effect of virtual reality training on unilateral spatial neglect in stroke patients

Objective

To investigate the effect of virtual reality training on unilateral spatial neglect in stroke patients.

Method

Twenty-four stroke patients (14 males and 10 females, mean age=64.7) who had unilateral spatial neglect as a result of right hemisphere stroke were recruited. All patients were randomly assigned to either the virtual reality (VR) group (n=12) or the control group (n=12). The VR group received VR training, which stimulated the left side of their bodies. The control group received conventional neglect therapy such as visual scanning training. Both groups received therapy for 30 minutes a day, five days per week for three weeks. Outcome measurements included star cancellation test, line bisection test, Catherine Bergego scale (CBS), and the Korean version of modified Barthel index (K-MBI). These measurements were taken before and after treatment.

Results

There were no significant differences in the baseline characteristics and initial values between the two groups. The changes in star cancellation test results and CBS in the VR group were significantly higher than those of the control group after treatment. The changes in line bisection test score and the K-MBI in the VR group were not statistically significant.

Conclusion

This study suggests that virtual reality training may be a beneficial therapeutic technique on unilateral spatial neglect in stroke patients.

Prism adaptation therapy enhances rehabilitation of stroke patients with unilateral spatial neglect: a randomized, controlled trial

BACKGROUND

and objective. Unilateral spatial neglect (USN) can interfere with rehabilitation processes and lead to poor functional outcome. The purpose of this study was to determine whether prism adaptation (PA) therapy improves USN and functional outcomes in stroke patients in the subacute stage.

METHODS

. A multicenter, double-masked, randomized, controlled trial was conducted to evaluate the effects of a 2-week PA therapy on USN assessed with the Behavioral Inattention Test (BIT), the Catherine Bergego Scale (CBS), and activities of daily living (ADL) as evaluated with the Functional Independence Measure (FIM). A total of 38 USN patients with right-brain damage were divided into prism (n = 20) and control (n = 18) groups. Patients were divided into mild and severe USN groups according to BIT behavioral test (mild ≥ 55 and severe<55). The prism group performed repetitive pointing with prism glasses that induce rightward optical shift twice daily, 5 days per week, for 2 weeks, whereas the control group performed similar pointing training with neutral glasses.

RESULTS

. The FIM improved significantly more in the prism group. In mild USN patients, there was significantly greater improvement of BIT and FIM in the prism group.

CONCLUSIONS

. PA therapy can significantly improve ADL in patients with subacute stroke.

Recent trends in rehabilitation interventions for visual neglect and anosognosia for hemiplegia following right hemisphere stroke

This article highlights the most recent findings regarding the rehabilitation interventions for the syndromes of visual neglect and anosognosia for hemiplegia that occur following right hemisphere stroke. We review papers published in the past 4 years pertaining to therapeutic approaches for these two syndromes in order to identify the trends in the development of effective interventions. Overall, it appears well recognized that visual neglect syndromes and awareness syndromes frequently co-occur and both include complex, multifaceted impairments leading to significant difficulties in daily life functioning following stroke. Thus, the interventions for these syndromes must be multifaceted in order to address the complex interplay of cognitive-behavioral-emotional components. There appears to be a trend for using combination therapeutic interventions that address these components.

Evaluating visual bias and effect of proprioceptive feedback in unilateral neglect

We propose modified versions of the line-bisection task for assessing visual bias and effect of proprioceptive feedback in unilateral neglect; that is, the verbal line-bisection (VLB) task and the VLB plus pointing task. The VLB task requires only a verbal response to assess pure visual bias. Conversely, the VLB plus pointing task requires both a verbal response and pointing to assess visual and proprioceptive bias. Ten patients with unilateral neglect were administered these tasks on a computer using presentation software. Eight participants showed obvious rightward deviation in the VLB task, and were thus classified as patients with visual neglect. Four participants showed significantly greater deviation in the VLB plus pointing task than in the VLB task, and were thus classified as patients with proprioceptive bias. Visual bias and effect of proprioceptive feedback in unilateral neglect were successfully assessed by these tasks.

Contribution of the superior colliculi to post-stroke unilateral spatial neglect and recovery

Unilateral spatial neglect (USN) is a highly prevalent and disabling consequence of stroke that often responds poorly to existing interventions. Its underlying neural mechanisms are still unclear. Recent work suggests that post-stroke USN may be partly related to a disruption of top-down and bottom-up control of visual attention mediated in part through the midbrain superior colliculi (SC). With mounting evidence from animal and human research, our objectives were: (1) to synthesize the literature implicating the SC in USN; (2) to review the rationale and potential for using eye patching and prism adaptation as USN treatment approaches that recruit SC involvement; and (3) to provide recommendations for research on the potential of therapeutic interventions that involve and/or target the retino-collicular pathway. Given the paucity of human studies, the contribution of the SC in USN, while plausible, remains to be confirmed. Further exploration of the mechanisms involved and their impact on USN in human subjects will help develop theoretically based intervention strategies tailored to USN type.

Pharmacotherapy for treatment of attention deficits after non-progressive acquired brain injury. A systematic review

Objective: To systematically review the effectiveness of medications used to improve attention in people with non-progressive acquired brain injury.

Design: A systematic review.

Methods: MEDLINE, EMBASE, CINALH, PUBMED and PsychINFO databases were used to identify studies published between 1987 and 2008 meeting the following criteria: studies with subjects older than 18 years; diagnosis of new onset or previous acquired brain injury; medication given to improve attention and use of outcome to measure attention. Studies involving subjects in low arousal states or with neurogenerative conditions were excluded. The studies were categorized into three evidence levels: I — Randomized controlled trials; II — Prospective studies, controlled trials with methodological limitations; and III — Retrospective studies, clinical case series.

Results: Forty-seven articles were identified on initial search. Twenty-six met the pre-specified criteria. Five articles were assessed as meeting the level I evidence criteria, 12 were level II studies and 9 were level III studies. Methylphenidate can improve information processing speed but not all attention aspects in some people after traumatic brain injury. There is weak evidence for use of dopamine agonists to improve neglect/inattention after stroke. There is little evidence on the frequency of adverse effects and long-term functional benefits.

Conclusion: Although there is lack of robust evidence to recommend the routine use of medication to improve attention after traumatic brain injury and stroke, the existing evidence indicates potential for benefit in some patents and therefore further research is warranted.