Prefrontal dysfunction in pediatric Tourette's disorder as measured by near-infrared spectroscopy.
BACKGROUND
Tourette's disorder (TD) is a chronic childhood-onset disorder characterized by the presence of multiple motor and vocal tics. Despite strong evidence that the pathophysiology of TD involves structural and functional disturbances of the basal ganglia and cortical frontal areas, in vivo imaging studies have produced conflicting results. Recent developments in near-infrared spectroscopy (NIRS) technology have enabled noninvasive assessment of brain function in people with psychiatric disorders.


METHODS
We asked 10 individuals with pediatric TD and 10 healthy controls who were age- and sex- matched to perform the Stroop color-word task during NIRS. We used prefrontal probes and a 24-channel NIRS machine to measure the relative concentrations of oxyhemoglobin (oxy-Hb) every 0.1 s during the task.


RESULTS
We found that oxy-Hb changes in the prefrontal cortex were significantly smaller in the TD group compared with the control group, especially in the left dorsolateral prefrontal cortex.


CONCLUSIONS
Our data suggest that individuals with pediatric TD have a reduced prefrontal hemodynamic response as measured by NIRS.
Department of Psychiatry, Nara Medical University School of Medicine, 840 Shijyou-cho, Kashihara, Nara, 634-8522, Japan. muro@naramed-u.ac.jp.
Kazuhiko
K
Yamamuro
Department of Psychiatry, Nara Medical University School of Medicine, 840 Shijyou-cho, Kashihara, Nara, 634-8522, Japan. toyosaku@naramed-u.ac.jp.
Toyosaku
T
Ota
Faculty of Nursing, Nara Medical University School of Medicine, Kashihara, Nara, Japan. jiida@naramed-u.ac.jp.
Junzo
J
Iida
Department of Psychiatry, Nara Medical University School of Medicine, 840 Shijyou-cho, Kashihara, Nara, 634-8522, Japan. yo-ko.chip@nifty.com.
Yoko
Y
Nakanishi
Department of Psychiatry, Nara Prefectural General Rehabilitation Center, Shiki, Nara, Japan. ura-mitsu0121@hotmail.co.jp.
Mitsuhiro
M
Uratani
Department of Psychiatry, Tenri Hospital, Tenri, Nara, Japan. hiroki-m@umin.ac.jp.
Hiroki
H
Matsuura
Department of Psychiatry, Nara Medical University School of Medicine, 840 Shijyou-cho, Kashihara, Nara, 634-8522, Japan. sweet_candy0505@yahoo.co.jp.
Naoko
N
Kishimoto
Department of Psychiatry, Nara Medical University School of Medicine, 840 Shijyou-cho, Kashihara, Nara, 634-8522, Japan. osho-kamonegi@hotmail.co.jp.
Shohei
S
Tanaka
Department of Education, Nara University of Education, Nara, Japan. gorosan@nara-edu.ac.jp.
Hideki
H
Negoro
Department of Psychiatry, Nara Medical University School of Medicine, 840 Shijyou-cho, Kashihara, Nara, 634-8522, Japan. toshik@naramed-u.ac.jp.
Toshifumi
T
Kishimoto
D001289:Attention Deficit Disorder with Hyperactivity / Q000150:complications / Q000378:metabolism; D016022:Case-Control Studies; D002648:Child; D006801:Humans; D008297:Male; D010108:Oxyhemoglobins / Q000378:metabolism; D017397:Prefrontal Cortex / Q000098:blood supply* / Q000378:metabolism*; D011597:Psychomotor Performance; D019265:Spectroscopy, Near-Infrared; D057190:Stroop Test; D005879:Tourette Syndrome / Q000150:complications / Q000378:metabolism* / Q000523:psychology
D010108:Oxyhemoglobins