Background

Fragile X syndrome is the most common inherited form of intellectual disability and a leading cause of autism. It results from the loss of function of the gene FMR1 and affects 1 in 7,000 males and 1 in 11,000 females (Hunter et al., 2014). Sensory processing impairments are prevalent in fragile X syndrome, with touch sensitivities being particularly common.  These touch sensitivities may be a primary cause of the aberrant eating habits along with maladaptive behaviours such as self-harm and repetitive behaviours seen in FXS.

Why did we do this study?

At present, published studies that have examined somatosensory processing have utilised parental report measure which, while clinically meaningful, have significant limitations for the investigation of therapeutics, primarily their subjective nature, imprecision and vulnerability to placebo effects. We therefore proposed to trial two methods of objectively quantifying somatosensory function in FXS: electroencephalography (EEG) determined somatosensory evoked potentials and the Cortical Metrics Brain Gauge tactile stimulator.

What did we do?

The study recruited 16 individuals with fragile X syndrome aged between 3-45 as well as a comparison group of people without a neurodevelopmental disorder. Participants completed a number of tasks: (1) an EEG whilst holding a device that delivered tactile stimulation to their fingertips; (2) A number of tasks just holding our tactile device and (3) measured resting heart rate and blood pressure. The parents/caregivers of these individuals also completed a series of questionnaires about their child.

What did we find?

Our initial findings suggest that the tactile device we used may be a valuable tool for accurately measuring touch processing in individuals with fragile X syndrome. Alongside this, individuals with fragile X syndrome potentially show differences in their EEG in brain areas related to touch compared with our comparison group.

Outputs

We are currently in the process of analysing and writing up the results of the study as a journal article. As articles are published, we will highlight them here.

Who conducted and funded the project?

The study was conducted by Dr Damien Wright, Dr Leena Williams and Dr Andrew Stanfield. This project was funded by a FRAXA Fellowship awarded to Dr Damien Wright. We would also like to thank the Fragile X Society UK for their help with participant recruitment.