Can Acute Photobiomodulation Improve Balance and Cognition in Individuals With Ataxia: a Pilot Feasibility Placebo Randomized Controlled Trial.

Cerebellar ataxias cause progressive impairments in balance, gait coordination, motor timing, and cognitive functions such as attention and executive control (Buckner, 2013; Salmi et al., 2010; Timmann & Daum, 2007). These symptoms substantially reduce independence and quality of life, and current treatments remain limited. There is an urgent need for safe, low-burden interventions that can support everyday functioning and potentially enhance compensatory neural processes.

Transcranial photobiomodulation (tPBM) uses red and near-infrared light (600-1100 nm) to modulate mitochondrial cytochrome-c oxidase, increasing ATP production, reducing oxidative stress, and improving cerebral blood flow (Hamblin, 2016; Salehpour et al., 2019). Several studies show that tPBM can acutely improve cognitive performance and motor control in both healthy adults and clinical groups (Barrett & Gonzalez-Lima, 2013; Chan et al., 2019; Henderson & Morries, 2017). A growing neurobiological literature suggests that light can penetrate posterior cortical areas sufficiently to modulate networks involving cerebellar-cortical loops (Jagdeo et al., 2012).

Importantly for ataxia, preliminary work shows that tPBM may acutely improve balance stability and gait metrics in older adults and patients with neurological conditions (Moro et al., 2022; Shin et al., 2021). In our own laboratory, we have observed immediate improvements in sway range and cognitive control in older adults after a 24-minute tPBM session applied over midline and posterior scalp regions. These medium to large size effects are consistent with enhanced sensorimotor integration and improved control of attention in distracting environments.

Given that individuals with cerebellar ataxia experience both motor incoordination and difficulties in maintaining cognitive stability under distracting conditions, tPBM is a promising non-pharmacological intervention worth preliminary investigation.

Study Overview

• Status: Not yet recruiting
• Conditions: Ataxia
• Intervention / Treatment: Other: Sham photobiomodulation; Device: Photobiomodulation

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Jonathan J Sinclair, DSc; Phone Number: +44787565153; Email: jksinclair@lancashire.ac.uk

Study Locations

• United Kingdom
  • Lancashire
    • Preston, Lancashire, United Kingdom, PR1 2HE
      • University of Central Lancashire
      • Contact: Sinclair; Phone Number: 07875651533; Email: jksinclair@lancashire.ac.uk

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age 18-70 years (inclusive)
• Diagnosis of ataxia
• Able to walk independently for at least 5 minutes, with or without an assistive device
• Able to stand safely for balance testing, with or without an assistive device
• Hemodynamically stable (stable blood pressure and heart rate at rest)
• On a stable medication regimen for ≥4 weeks prior to enrolment
• Sufficient vision and hearing (with usual aids if required) to complete balance and cognitive assessments
• Able to complete study questionnaires and cognitive tasks (with assistance for reading/writing if required)
• Able and willing to provide written informed consent

Exclusion Criteria:

• Current or past history of head injury
• Use of medications acting on the central nervous system
• Active skin conditions on the forehead or scalp
• Any other major neurological disorder that could independently affect balance or cognition
• Ongoing brain stimulation therapy
• History of migraines
• Sensitive skin, allergies

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Sham Comparator: Sham photobiomodulation; Sham photobiomodulation. The sham device will follow the same protocol but without active light emission.	Other: Sham photobiomodulation; The sham device will follow the same protocol but without active light emission.
Experimental: Photobiomodulation; Acute photobiomodulation Twenty-four-minute photobiomodulation stimulation (twelve minutes at 670 nm followed by twelve minutes at 810 nm).	Device: Photobiomodulation; Photobiomodulation

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
n-1-back (deviation)	The n-1-back (deviation) task is a working memory test where participants respond when the current stimulus differs from the one presented n-1 trials earlier.	Baseline
n-1-back (deviation)	The n-1-back (deviation) task is a working memory test where participants respond when the current stimulus differs from the one presented n-1 trials earlier.	1 hour

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Beck Depression Inventory	Psychological wellbeing - the Beck Depression Inventory is a 21 questionnaire with questions that range in scoring from 0-3, thus the maximum score is 63 which is the highest depression score possible.	Baseline
n-2-back (deviation)	The n-2-back (deviation) task is a working memory test where participants respond when the current stimulus differs from the one presented n-2 trials earlier.	Baseline
n-2-back (deviation)	The n-2-back (deviation) task is a working memory test where participants respond when the current stimulus differs from the one presented n-2 trials earlier.	1 hour
n-1-back (post-deviation)	The n-1-back (post-deviation) task assesses working memory performance on the trial immediately following a deviation from the stimulus presented n-1 trials earlier.	Baseline
n-1-back (post-deviation)	The n-1-back (post-deviation) task assesses working memory performance on the trial immediately following a deviation from the stimulus presented n-1 trials earlier.	1 hour
n-2-back (post-deviation)	The n-2-back (post-deviation) task assesses working memory performance on the trial immediately following a deviation from the stimulus presented n-2 trials earlier.	Baseline
n-2-back (post-deviation)	The n-2-back (post-deviation) task assesses working memory performance on the trial immediately following a deviation from the stimulus presented n-2 trials earlier.	1 hour
n-1-back (post-target)	The n-1-back (post-target) task assesses working memory performance on the trial immediately following a target that matched the stimulus presented n-1 trials earlier.	Baseline
n-1-back (post-target)	The n-1-back (post-target) task assesses working memory performance on the trial immediately following a target that matched the stimulus presented n-1 trials earlier.	1 hour
n-1-back (load)	The n-1-back (load) condition measures working memory performance under the cognitive demand of tracking stimuli 1 trial back.	Baseline
n-1-back (load)	The n-1-back (load) condition measures working memory performance under the cognitive demand of tracking stimuli 1 trial back.	1 hour
n-2-back (post-load)	The n-2-back (post-load) condition assesses working memory performance on the trial immediately following a high cognitive load in the n-2-back task.	Baseline
n-2-back (post-load)	The n-2-back (post-load) condition assesses working memory performance on the trial immediately following a high cognitive load in the n-2-back task.	1 hour
Coop-Wonka chart	The Coop-Wonka chart is a six item questionnaire with a 1-5 scoring system for each thus the chart has a maximum score of 30 which indicates the lowest possible psychological Wellbeing.	Baseline
Coop-Wonka chart	The Coop-Wonka chart is a six item questionnaire with a 1-5 scoring system for each thus the chart has a maximum score of 30 which indicates the lowest possible psychological Wellbeing.	1 hour
Beck Depression Inventory	Psychological wellbeing - the Beck Depression Inventory is a 21 questionnaire with questions that range in scoring from 0-3, thus the maximum score is 63 which is the highest depression score possible.	1 hour
Pittsburgh Sleep Quality Index	The Pittsburgh Sleep Quality index, is a questionnaire that consists of 19 self-rated questions, grouped into 7 components. Each component is scored separately, weighted equally on a 0 - 3 scale and the scores of the 7 components are then added to give a global score, which has a range of 0 - 21 with higher scores indicating worse sleep quality.	Baseline
Pittsburgh Sleep Quality Index	The Pittsburgh Sleep Quality index, is a questionnaire that consists of 19 self-rated questions, grouped into 7 components. Each component is scored separately, weighted equally on a 0 - 3 scale and the scores of the 7 components are then added to give a global score, which has a range of 0 - 21 with higher scores indicating worse sleep quality.	1 hour
State Trait Anxiety Inventory	The state trait anxiety inventory is a 40 item questionnaire with each question having a 1-4 score system, thus the maximum score is 80 which indicates the highest level of anxiety.	Baseline
State Trait Anxiety Inventory	The state trait anxiety inventory is a 40 item questionnaire with each question having a 1-4 score system, thus the maximum score is 80 which indicates the highest level of anxiety.	1 hour
Insomnia Severity Index	The Insomnia Severity Index is a brief instrument designed to assess the severity of both nighttime and daytime components of insomnia. The Insomnia Severity Index is a 7-item self-report questionnaire yielding a total score ranging from 0 to 28.	Baseline
Insomnia Severity Index	The Insomnia Severity Index is a brief instrument designed to assess the severity of both nighttime and daytime components of insomnia. The Insomnia Severity Index is a 7-item self-report questionnaire yielding a total score ranging from 0 to 28.	1 hour
Epworth Sleepiness Scale	The Epworth Sleepiness Scale is a self-administered questionnaire with 8 questions. Respondents are asked to rate, on a 4-point scale (0-3) with a maximum score of 24.	Baseline
Epworth Sleepiness Scale	The Epworth Sleepiness Scale is a self-administered questionnaire with 8 questions. Respondents are asked to rate, on a 4-point scale (0-3) with a maximum score of 24.	1 hour
Everyday Memory Errors Questionnaire	The Everyday Memory Errors Questionnaire is a brief self-report instrument designed to assess the frequency of memory lapses in daily life. It consists of multiple items that yield a total score reflecting the extent of everyday memory difficulties.	Baseline
Everyday Memory Errors Questionnaire	The Everyday Memory Errors Questionnaire is a brief self-report instrument designed to assess the frequency of memory lapses in daily life. It consists of multiple items that yield a total score reflecting the extent of everyday memory difficulties.	1 hour
Falls Efficacy	The Falls Efficacy Scale is a brief self-report instrument designed to assess confidence in performing daily activities without falling. It consists of multiple items that yield a total score reflecting fear of falling and perceived fall-related self-efficacy.	Baseline
Falls Efficacy	The Falls Efficacy Scale is a brief self-report instrument designed to assess confidence in performing daily activities without falling. It consists of multiple items that yield a total score reflecting fear of falling and perceived fall-related self-efficacy.	1 hour
Anterior-posterior balance	The maximum anterior-posterior displacement of the centre of pressure during a two-minute balance task.	Baseline
Anterior-posterior balance	The maximum anterior-posterior displacement of the centre of pressure during a two-minute balance task.	1 hour
Medio-lateral balance	The maximum medio-lateral displacement of the centre of pressure during a two-minute balance task.	Baseline
Medio-lateral balance	The maximum medio-lateral displacement of the centre of pressure during a two-minute balance task.	1 hour
n-2-back (post-target)	The n-2-back (post-target) task assesses working memory performance on the trial immediately following a target that matched the stimulus presented n-2 trials earlier.	Baseline
n-2-back (post-target)	The n-2-back (post-target) task assesses working memory performance on the trial immediately following a target that matched the stimulus presented n-2 trials earlier.	1 hour

Collaborators and Investigators

• Sponsor: University of Central Lancashire

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): June 1, 2027
• Study Completion (Estimated): December 10, 2027

Study Registration Dates

• First Submitted: December 8, 2025
• First Submitted That Met QC Criteria: December 8, 2025
• First Posted (Actual): December 22, 2025

Study Record Updates

• Last Update Posted (Actual): December 22, 2025
• Last Update Submitted That Met QC Criteria: December 8, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Dyskinesias; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Ataxia; Therapeutics; Laser Therapy; Phototherapy; Low-Level Light Therapy
• Other Study ID Numbers: PMB Ataxia pilot feasibility s

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No