New research suggests sensitivity to bodily sensations such as your heartbeat, links to premonitory sensations and tic severity

Posted on 17 December 2018

Share

Researchers at Brighton and Sussex Medical School reveal their research findings and what this could mean for future TS treatments.

People with TS are often very aware of sensations in their body, such as heartbeats, breathing, and palms sweating. Scientists call these inner feelings ‘interoception’. Researchers at Brighton and Sussex Medical School examined if interoception is different in people with tics, and whether these inner feelings are linked to the premonitory sensations, or ‘urges’, that many with TS experience before tics.

A group of twenty-one people with TS and 22 people without TS were tested on a set of ‘interoception’ tests, which compared how accurately people could feel their heart beating. The actual number of heartbeats was measured using a sensor placed on a finger (the same type of sensor, called a pulse oximeter, is often used by doctors, such as GPs, to take patients’ pulse rates). Each participant counted the number of heartbeats that they felt over different time intervals and this was compared to the actual number of heartbeats. They then performed a test to see how well they could judge whether or not their heartbeats were in or out of time with a set of beeps played to them by the researcher. Participants also filled out questionnaires about how much, in general, they experienced bodily sensations, e.g. “I am often aware if my heart is beating fast”.

The study suggested that people with TS were not much different from people without TS (perhaps, a little worse) in how accurately they could judge their heartbeats. On the questionnaires, again people with TS were not much different from the people without TS (perhaps, a little more sensitive to day-to-day inner feelings). The people with TS were found to be different from people without TS when the poor heartbeat accuracy results were combined with the high questionnaire scores.

The researchers also found that people with TS who were more sensitive to frequent bodily feelings in everyday life (high questionnaire scores), experienced more premonitory sensations before tics, and also had more frequent and severe tics. This suggests that TS symptoms may be made worse by being more sensitive to inner bodily sensations, including feelings that are often associated with stress, such as stronger heartbeats, or faster breathing.

This is perhaps the most important finding, because it suggests that therapies that focus on helping to control sensitivity to bodily sensations can also help manage the urge to tic and the occurrence of tics themselves. Indeed, paying attention to bodily feelings is part of current behavioural therapies, such as Habit Reversal Therapy (HRT) and Comprehensive Behavioural Intervention for Tics (CBIT) therapy. The new results indicate that interoception-based therapies can help people with TS manage symptoms.

Professor Hugo Critchley, who led the research, said “We are currently testing whether changing interoceptive experience can help reduce anxiety in people with Autism Spectrum Conditions.  We are now thinking about ways we might adapt these approaches to help people with tics too.”

The research team would like to thank each participant who took part for lending their time (and their hearts) to the study, and Tourettes Action for helping us advertise the study to participants.

Please contact researcher Charlotte Rae for a copy of the full paper

Return to news