John Andersen

Brain-controlled powered wheelchairs represent a promising advancement for individuals with neurological conditions that significantly impair motor function. Despite substantial progress, brain-controlled wheelchairs have not been adapted for real-world settings. This article systematically reviews recent trends in brain-computer interface (BCI) technology for wheelchair navigation and control, highlighting the contributions and limitations of various navigation paradigms. This review was conducted in accordance with the PRISMA guidelines, sourcing studies from four databases (PubMed, Scopus, IEEE Xplore, Google Scholar) published between 2000 and April 2025. This review focused on non-invasive BCI paradigms and real-world navigation experiments. The results were narratively synthesized and classified into two primary categories: BCI-based navigation paradigms and wheelchair-based navigation paradigms, along with intersecting concepts such as single-variant BCI, hybrid BCI, control switches, and proportional control. Of the 149 full-text articles reviewed, 47 were included and categorized by navigation paradigm, comprising 20 BCI-based and 27 wheelchair-based studies, with 6 involving participants with motor disabilities. Quality assessment scores ranged from 40% to 95%, with approximately 40% of the studies demonstrating a low risk of bias. The findings indicate that low-level navigation control was predominant in BCI wheelchair studies, with 31 studies employing minimal or no obstacle avoidance. Most studies (57%) integrated sensors for obstacle avoidance, localization, mapping, and autonomous navigation. Twenty-two studies utilized control switches, and five incorporated proportional control for wheelchair navigation. Additionally, motor imagery and steady-state visually evoked potential (SSVEP) paradigms have emerged as the most common approaches for generating control commands, highlighting their potential for effective navigation. Given the potential societal impact on a large number of individuals, future research should prioritize enhancing the reliability and adaptability of BCI wheelchair systems in real-world environments.

Background: Perinatal stroke injures motor regions of the brain, compromising movement for life. Early, intensive, active interventions for the upper extremity are efficacious, but interventions for the lower extremity remain understudied. Objective: To determine the feasibility and potential efficacy of ELEVATE—Engaging the Lower Extremity Via Active Therapy Early—on gross motor function. Methods: We conducted a single-blind, two-arm, randomized controlled trial (RCT), with the Immediate Group receiving the intervention while the Delay Group served as a 3-month waitlist control. A separate cohort living beyond commuting distance was trained by their parents with guidance from physical therapists. Participants were 8 months to 3 years old, with MRI-confirmed perinatal ischemic stroke and early signs of hemiparesis. The intervention was play-based, focused on weight-bearing, balance and walking for 1 hour/day, 4 days/week for 12 weeks. The primary outcome was the Gross Motor Function Measure-66 (GMFM-66). Secondary outcomes included steps and gait analyses. Final follow-up occurred at age 4. Results: Thirty-four children participated (25 RCT, 9 Parent-trained). The improvement in GMFM-66 over 12 weeks was greater for the Immediate than the Delay Group in the RCT (average change 3.4 units higher) and greater in younger children. Average step counts reached 1370-3750 steps/session in the last week of training for all children. Parent-trained children also improved but with greater variability. Conclusions: Early, activity-intensive lower extremity therapy for young children with perinatal stroke is feasible and improves gross motor function in the short term. Longer term improvement may require additional bouts of intervention. Clinical trial registration: This study was registered at ClinicalTrials.gov (NCT01773369).

The goal of this study was to examine executive functioning, math performance, and visuospatial processing skills of children with perinatal stroke, which have not been well explored in this population. Participants included 18 children with perinatal stroke (aged 6-16 years old) and their primary caregiver. Each child completed standardized tests of executive function and visuospatial processing skills, Intelligence Quotient (IQ), and math achievement. Performance on executive function, IQ, math, and visuospatial processing tests was significantly lower in children with perinatal stroke when compared to normative means. Poorer inhibitory control was associated with worse math performance. Increased age at testing was associated with better performance on visuospatial ability (using standardized scores), and females performed better than males on a test of inhibitory control. Children with perinatal stroke displayed a range of neuropsychological impairments, and difficulties with executive function (inhibition) may contribute to math difficulties in this population.

Background Perinatal stroke injures motor regions of the brain, compromising movement for life. Early, intensive, active interventions for the upper extremity are efficacious, but interventions for the lower extremity (LE) remain infrequent and understudied. Objective To determine the efficacy of ELEVATE – Engaging the Lower Extremity Via Active Therapy Early - on gross motor function, as compared to usual care. Method We conducted a single-blind, two-arm, randomized controlled trial (RCT), with the Immediate Group receiving the intervention while the Delay Group served as a three-month waitlist-control. A separate cohort living beyond commuting distance was trained by their parents with guidance from physical therapists. Participants were 8 months to 3 years old, with MRI-confirmed perinatal ischemic stroke and early signs of hemiparesis. The intervention was play-based, focused on weight-bearing, balance and walking for 1 hour/day, 4 days/week for 12 weeks. The primary outcome was the Gross Motor Function Measure-66 (GMFM-66). Secondary outcomes included steps and gait analyses. Final follow-up occurred at age four. Results Thirty-four children participated (25 RCT, 9 Parent-trained). The improvement in GMFM-66 over 12 weeks was greater for the Immediate than the Delay Group (average change 3.4 units higher) and greater in younger children. Average step counts reached 1370–3750 steps/session in the last week of training for all children. Parent-trained children also improved but with greater variability. Conclusions Early, activity-intensive LE therapy for young children with perinatal stroke is feasible and improves gross motor function in the short term. Longer term improvement may require additional bouts of intervention. Clinical trial registratio This study was registered at ClinicalTrials.gov (NCT01773369).

To explore child, parent, and clinician experiences with a child-driven approach to rehabilitation goal setting. Nine children receiving inpatient and outpatient rehabilitation aged 5.0–12.3 years ...

Objective To specifically report on ataxic-hypotonic cerebral palsy (CP) using registry data and to directly compare its features with other CP subtypes. Methods Data on prenatal, perinatal, and neonatal characteristics and gross motor function (Gross Motor Function Classification System [GMFCS]) and comorbidities in 35 children with ataxic-hypotonic CP were extracted from the Canadian Cerebral Palsy Registry and compared with 1,804 patients with other subtypes of CP. Results Perinatal adversity was detected significantly more frequently in other subtypes of CP (odds ratio [OR] 4.3, 95% confidence interval [CI] 1.5–11.7). The gestational age at birth was higher in ataxic-hypotonic CP (median 39.0 weeks vs 37.0 weeks, p = 0.027). Children with ataxic-hypotonic CP displayed more intrauterine growth restriction (OR 2.6, 95% CI 1.0–6.8) and congenital malformation (OR 2.4, 95% CI 1.2–4.8). MRI was more likely to be either normal (OR 3.8, 95% CI 1.4–10.5) or to show a cerebral malformation (OR 4.2, 95% CI 1.5–11.9) in ataxic-hypotonic CP. There was no significant difference in terms of GMFCS or the presence of comorbidities, except for more frequent communication impairment in ataxic-hypotonic CP (OR 4.2, 95% CI 1.5–11.6). Conclusions Our results suggest a predominantly genetic or prenatal etiology for ataxic-hypotonic CP and imply that a diagnosis of ataxic-hypotonic CP does not impart a worse prognosis with respect to comorbidities or functional impairment. This study contributes toward a better understanding of ataxic-hypotonic CP as a distinct nosologic entity within the spectrum of CP with its own pathogenesis, risk factors, clinical profile, and prognosis compared with other CP subtypes.

Background: Individuals with severe neurological disabilities but preserved cognition, including children, are often precluded from connecting with their environments. Brain computer interfaces (BCI) are a potential solution where advancing technologies create new clinical opportunities. We evaluated clinician awareness as a modifiable barrier to progress and identified eligible populations. Methods: We executed a national, population-based, cross-sectional survey of physician specialists caring for persons with severe disability. An evidence- and experience-based survey had three themes: clinician BCI knowledge, eligible populations, and potential impact. A BCI knowledge index was created and scored. Canadian adult and pediatric neurologists, physiatrists and a subset of developmental pediatricians were contacted. Secure, web-based software administered the survey via email with online data collection. Results: Of 922 valid emails (664 neurologists, 253 physiatrists), 137 (15%) responded. One third estimated that ≥10% of their patients had severe neurological disability with cognitive capacity. BCI knowledge scores were low with > 40% identifying as less than “vaguely aware” and only 15% as “somewhat familiar” or better. Knowledge did not differ across specialties. Only 6 physicians (4%) had patients using BCI. Communication and wheelchair control rated highest for potentially improving quality of life. Most (81%) felt BCI had high potential to improve quality of life. Estimates suggested that > 13,000 Canadians (36 M population) might benefit from BCI technologies. Conclusions: Despite high potential and thousands of patients who might benefit, BCI awareness among clinicians caring for disabled persons is poor. Further, functional priorities for BCI applications may differ between medical professionals and potential BCI users, perhaps reflecting that clinicians possess a less accurate understanding of the desires and needs of potential end-users. Improving knowledge and engaging both clinicians and patients could facilitate BCI program development to improve patient outcomes.