TABLE 1.
Children |
Adults |
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---|---|---|---|---|---|---|---|---|
Characteristic | Tourette Syndrome (N=22) |
Healthy Comparison Subjects (N=21) |
Tourette Syndrome (N=29) |
Healthy Comparison Subjects (N=48) |
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N | % | N | % | N | % | N | % | |
Sexb | ||||||||
Male | 19 | 86.4 | 12 | 57.1 | 17 | 58.6 | 21 | 43.7 |
Female | 3 | 13.6 | 9 | 42.9 | 12 | 41.4 | 27 | 56.3 |
Mean | SD | Mean | SD | Mean | SD | Mean | SD | |
Age | 13.1 | 2.6 | 13.4 | 3.1 | 35.1 | 11.1 | 31.4 | 11.0 |
Socioeconomic status | 50.8 | 9.6 | 48.9 | 11.8 | 43.9 | 10.1 | 48.4 | 12.2 |
IQ (Wechsler Abbreviated Scale of Intelligence) | 116.0 | 12.1 | 116.1 | 13.4 | 117.3 | 14.9 | 120.7 | 13.7 |
Motion indexc | 8.8 | 10.4 | 4.9 | 3.3 | 5.9 | 3.7 | 4.2 | 2.9 |
Yale Global Tic Severity Scale scored | ||||||||
Total current | 18.5 | 11.1 | 21.0 | 10.6 | ||||
Total worst ever | 28.9 | 8.6 | 30.2 | 9.2 | ||||
Yale-Brown Obsessive Compulsive Scalee | ||||||||
Total current | 3.4 | 6.6 | 8.8 | 9.5 | ||||
Total worst ever | 9.1 | 13.7 | 10.9 | 11.9 | ||||
ADHD Rating Scale total score | ||||||||
Current | 14.3 | 12.6 | 18.8 | 7.8 | ||||
Pre-medicationf | 26.5 | 18.7 | 20.2 | 10.1 |
A total of 63 participants with Tourette syndrome and 70 comparison subjects were scanned, but 12 with Tourette syndrome were excluded due to ghosting artifact (N=8) or excessive movement (N=4). Among these excluded participants, seven were male and five were female; four were children and eight were adults. Only one adult male comparison participant was excluded due to ghosting artifact.
Differences between groups were calculated using unpaired t tests. A significant difference was found in gender ratio in children (t= 2.20, df=41, p=0.03).
Calculated as the maximum motion of a 4×4×4mm3 cube at the center of the brain moving along a three-dimensional trajectory over time, where the trajectory was reconstructed from a series of six motion parameters (three translations and three rotations in a rigid-body transformation) that were generated during motion realignment of the fMRI time series. A significant between-group difference was found in motion index among adults (t=2.18, df=75, p=0.03). Regional activations in both groups assessed separately did not correlate significantly with motion index, and covarying with this motion index in our statistical analyses did not appreciably alter any of our findings.
Twenty-five Tourette patients had eye-blinking tics at the time of the study. Among them, 14 were children and 11 were adults.
OCD symptoms were significantly more severe at the time of scan for Tourette adults than for Tourette children (t=−2.29, df=49, p=0.02).
Twenty-one Tourette syndrome participants were taking medications at the time of the study, including typical neuroleptics (N=5), risperidone (N=4), α-adrenergic agonists (N=2), serotonin reuptake inhibitors (N=11), levothyroxine (N=2), and valproic acid (N=2). Medications were not mutually exclusive.