Subject:
TIC DISORDER

Short Description:
Attention Not a Problem in Tic Disorders

Background:
Children and adolescents with tic disorders (TD) very often have comorbid psychiatric diagnoses. In fact, some research shows that up to 90% of these kids have at least one additional condition (Freeman RD et al, Develop Med Child Neurol 2000;42(5):436–447). All these diagnoses can make it difficult to figure out which condition is causing which symptoms. Researchers recently set out to determine if a TD itself is the cause of the attention problems sometimes seen in these kids, versus the other way around (the ADHD causing the TD). In this German study, 96 kids between the ages of eight and 17 (mean age 12) were given a series of four tests related to various aspects of attention. The children were diagnosed with either tic disorder (21 participants), ADHD (23 participants), comorbid tic disorder and ADHD (25 participants), or were part of a control group with no psychiatric diagnoses (27 participants). None of the participants had a psychiatric disorder that has shown a great impact on neuropsych test performance or general functioning, such as conduct disorder, oppositional defiant disorder, OCD, pervasive developmental disorders, affective disorders, posttraumatic stress disorder, or psychosis. However, children with elimination disorder, specific developmental disorders, specific childhood-onset emotional disorders, and specific phobias were allowed to participate. None of the participants were taking medication at the time of the testing. The children took four computer tests over a period of about 40 minutes to assess different aspects of attention: a sustained attention task that involved identifying specific target patterns of dots tested the “intensity” domain; a divided attention task focused on discriminating audio and visual cues tested “attention selectivity”; a go/no go task that required a response to stimulus, and a visual set shifting task both tested the “supervisory attentional system.” As might be expected, children with ADHD performed poorly on all tests, both in reaction time and number of errors. Children with comorbid ADHD and TD tended to perform poorly on most tasks as well. However, TD alone was found to have no negative effect on any of the attention measures. In fact, the group with TD alone outperformed all others in the set shifting task—their mean reaction time was 12% to 14% faster than that of the control group (Greimel E et al, J Abnorm Child Psychol 2011; online ahead of print).

TCPR's Take:
So what does this mean for our practices? First, it’s an interesting lesson in the way a young brain works, since researchers think the superior performance in the set shifting task among the TD-only group might be associated with increased prefrontal control mechanisms in these kids—the same part of their brains they use to suppress tics. Second, this suggests that any attentional problems we see in children and adolescents with comorbid ADHD and TD are most likely due to the ADHD, and we should focus our treatment on that condition.