Children with Tourette's Syndrome, the neurodevelopmental condition characterised by involuntary motor and verbal tics, have superior timing abilities compared with their healthy age-matched peers, a new study suggests.
Carmelo Vicario and colleagues tested nine children with Tourette's (average age 11 years) and 10 controls (average age 12) on timing perception and timing production. The former involved the children judging whether two circles were on screen for the same length of time or not. The latter task involved the children noting the time that a circle appeared on-screen and then pressing the space key on a key board for the same duration. Half the trials involved intervals in the sub-second range (from 310ms to 500ms), the other half were longer than a second, up to 1900ms.
There was no difference between the groups on timing perception or sub-second timing production. However, the children with Tourette's were more accurate at the longer 'supra-second' version of the timing production task.
Vicario's team aren't entirely sure why the children with Tourette's showed this advantage. However, past research suggests that tic suppression is associated with activity in the dorsolateral prefrontal cortex and the supplementary area - two areas which are also known to be involved in control of timing. Consistent with this, the children with less severe tics, perhaps by virtue of their greater control over those tics, also tended to be the children who most excelled at the timing production task.
The children were also tested on other factors that could be relevant, including attention and working memory, but scores on these tasks didn't correlate with performance on the timing tasks.
This new finding of enhanced timing control in Tourette's comes after a 2006 study that found children with the condition exhibited superior self-control in an eye-movement task. A study published in 2007, meanwhile, reported Tourette's was associated with superior grammatical abilities.
'The present data are in support of an enhancement of cognitive control processes in Tourette's Syndrome children, probably facilitated by effortful tic suppression,' the researchers said.
Vicario, C., Martino, D., Spata, F., Defazio, G., Giacchè, R., Martino, V., Rappo, G., Pepi, A., Silvestri, P., & Cardona, F. (2010). Time processing in children with Tourette’s syndrome. Brain and Cognition, 73 (1), 28-34 DOI: 10.1016/j.bandc.2010.01.008