NotesFAQContact Us
Search Tips
Peer reviewed Peer reviewed
Direct linkDirect link
ERIC Number: EJ891883
Record Type: Journal
Publication Date: 2007-May
Pages: 5
Abstractor: As Provided
Reference Count: 27
ISSN: ISSN-0012-1622
Early Initiation of L-Dopa Therapy Enables Stable Development of Executive Function in Tetrahydrobiopterin (BH4) Deficiency
Tanaka, Yoko; Kato, Motoichiro; Muramatsu, Taro; Saito, Fumie; Sato, Seiji; Matsuo, Nobutake; Shintaku, Haruo; Okano, Yoshiyuki; Kondo, Hiroshi; Nukazawa, Tatsushi
Developmental Medicine & Child Neurology, v49 n5 p372-376 May 2007
Executive function (EF) has been presumed to be mediated by the dopaminergic system in the prefrontal cortex. However, little is known about the early development of this function and the roles dopamine plays in it. Tetrahydrobiopterin (BH4) deficiencies are genetic disorders affecting catecholamine and serotonin biosynthesis which, if untreated, result in motor and cognitive symptoms including impairment of EF. A comprehensive neuropsychological test battery was administered to six participants with BH4 deficiency (four males, two females, mean Full-scale intelligence quotient [FIQ] 63.8 [SD 14.7]); all were on replacement therapy with L-dopa and BH4, but time of initiation of treatment varied. Age range (median) was 28 days to 41 years (2y 6mo) at initiation of treatment and 10 to 47 years (19y) at follow-up. On non-EF tests, performance agreed with those of IQ-matched controls (four males, two females; mean age 16y 6mo [SD 6mo]; mean FIQ 62.3 [SD 13.4]). On EF tests those who initiated treatment after 2 years 6 months of age performed poorly. In patients with BH4 deficiency, replacement therapy should be started in the first weeks or months of life. Patients diagnosed before the age of 2 years 6 months obtain normal EF, which suggests dopamine may play a critical role in ensuring stable development of EF in early life. (Contains 1 table, 1 figure, and 1 footnote.)
Wiley-Blackwell. 350 Main Street, Malden, MA 02148. Tel: 800-835-6770; Tel: 781-388-8598; Fax: 781-388-8232; e-mail:; Web site:
Publication Type: Journal Articles; Reports - Research
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A