Autism
Conditions
Keywords
Vitamin B6, Sensory Hyperreactivity, GABA, Excitation-Inhibition Balance, Autism
Brief summary
This clinical trial aims to explore the effect of Vitamin B6 supplementation on anxiety sensory hyperreactivity in autistic adults. Researchers will compare a placebo group to high-dose Vitamin-B6 to see if vitamin B6 reduce anxiety and sensory reactivity differences in autism.
Detailed description
The main question it aims to answer is: * Does high-dose Vitamin B6 supplementation reduce sensory hyperreactivity differences in autism? * Does high-dose Vitamin B6 supplementation reduce anxiety differences in autism? * Explore the effects of vitamin B6 on sleep quality, Attention Deficit Hyperactivity Disorder (ADHD) scores, and various visual perception tasks that are indicative of GABAergic activity
Interventions
DIETARY_SUPPLEMENTPyridoxal 5'-Phosphate (100 mg)
100 mg Pyridoxal 5'-Phosphate tablet once daily with food
OTHERPlacebo
Placebo tablet once daily
Sponsors
University of Reading
INNOPURE
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
No
Inclusion criteria
* Between the ages of 18 to 60 * With a diagnosis of autism
Exclusion criteria
* Taking any supplement that contains more than 2mg of Vitamin B6 or taking GABA agonist drugs * Have a medical history of peripheral neuropathy * lactose intolerance (placebo tablet is lactose based)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Sensory hyperreactivity | Baseline and One month | Sensory hyperreactivity will be measured by a subscale of the Sensory Processing Inventory (SP3D. |
| Anxiety | Baseline and One month | Anxiety will be measured using the Screen for Adult Anxiety Related Disorders (SCAARED) questionnaire. |
| Vitamin B6 status | Baseline and One month | The concentration of different forms of Vitamin B6 in blood plasma will be measured (Pyridoxal-5'-phosphate, pyridoxine, pyridoxal, pyridoxamine) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| ADHD traits | Baseline and One month | Adult Attention Deficit Hyperreactivity Disorder Self-Report Scale (ASRS-v1.1) |
| Sensory processing differences | Baseline and One month | These will be measured using the other subscales of the Sensory Processing Inventory (SP3D) that do not constitute the primary sensory hyperreactivity outcome described above. |
| Sleep quality | Baseline and One month | Pittsburgh Sleep Quality Index (PSQI) |
| Visual Surround Suppression of contrast perception | Baseline and One month | Psychophysical measurements of the contrast threshold will be made, which correspond to the minimum physical stimulus contrast that can be reliably detected by an observer. The test measures the increase in the threshold caused by introducing spatial inhibition of the target stimuli, which is a parameter that has been shown to correlate with GABA concentration in the brain (Yoon et al., 2010). |
| Surround Suppression of Motion duration detection thresholds | Baseline and One month | Psychophysical measurements of the motion duration threshold will be made, which correspond to the number of milliseconds an observer requires to detect whether a Gabor patch is drifting left or right. The test measures the increase in the threshold caused by spatial inhibition, which is a parameter that has been shown to differ in various patient groups, including autism (Foss-Feig et al. 2013). |
| Binocular Rivalry reversal rate | Baseline and One month | A test based on presenting ambiguous visual stimuli that cause perceptual reversals; how frequently the perceptual reversals occur is measured and has been shown to be related to GABA levels (Mentch et al., 2019). |
| Binocular Rivalry suppression index | Baseline and One month | A test based on presenting ambiguous visual stimuli that cause perceptual reversals; the proportion of time for which the stimulus appears unclear rather than stable is measured and has been shown to be related to GABA levels (Mentch et al., 2019). |
| Measurement of Weber Fraction for size perception | Baseline and One month | The Weber fraction is the percentage change in a physical quantity required for an observer to reliably detect that a change has occurred, and for a specific stimulus type it is generally a fixed percentage regardless of the magnitude of the stimuli. We will measure the Weber Fraction for visual size perception at four separate starting sizes, and the outcome measure derived from doing that will be a measurement of the stability/instability of the Weber Fraction across the four starting sizes. It has been reported that in autism the general finding of fixed Weber fractions across a range of physical stimuli does not hold (Hadad \& Schwartz, 2019): we are taking the opportunity to replicate this finding. |
| Tilt illusion magnitude | Baseline and One month | Magnitude of the tilt illusion is a correlate of GABA concentration in the occipital cortex (Song et al., 2017). |
| Ebbinghaus illusion magnitude | Baseline and One month | Magnitude of the Ebbinghaus illusion is a correlate of gamma y-Aminobutyric acid (GABA) concentration in the parietal lobe (Song et al. 2017) |
Countries
United Kingdom
Contacts
CONTACTDr David T Field, PhD
CONTACTAlex Cameron, MSc
PRINCIPAL_INVESTIGATORDr David T Field, PhD
University of Reading
Outcome results
None listed