Lawrence H Pick

City University of New York - Queens College, New York City, New York, United States

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Publications (3)25.46 Total impact

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    ABSTRACT: Background: The stability and developmental variation of severl neurobiological measures in boys with attention-deficit hyperactivity disorder (ADHD) were examined.Methods: The prolactin (PRL) response to fenfluramine (FEN) challenge was used to assess central serotonergic (5-HT) functioning in 10 8–11-year-old boys with ADHD. In addition, platelet 5-HT, as well as plasma levels of the catecholamine metabolites 3-methoxy-4-hydroxyphenyl-glycol (MHPG) and homovanillic acid were ascertained. These neurobiological variables were reassessed in the same children 2–3 years later using the identical procedures.Results: The PRL response to FEN challenge was the only measure found to be stable across the evaluations (r = .58), although the magnitude of the response decreased significantly with age. Plasma MHPG level significantly increased with age.Conclusions: Central 5-HT function, as measured by the PRL response to FEN, may represent a stable trait. The importance of considering developmental factors when interpreting neurobiological data is discussed.
    Biological Psychiatry 03/1999; · 9.25 Impact Factor
  • Biological Psychiatry 01/1999; 45(3). · 9.25 Impact Factor
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    ABSTRACT: ObjectiveTo examine noradrenergic (NA) function in children with attention-deficit hyperactivity disorder (ADHD) by replicating and expanding upon a previous finding that ADHD children with and without reading disabilities (RD) differ in plasma levels of the NA metabolite 3-methoxy-4-hydroxyphenylglycol (MHPG).MethodPlasma levels of MHPG were compared in ADHD children who were subdivided on the basis of the presence or absence of RD. Subsequently, this replication sample was combined with a previously studied sample to further explore the relationship between plasma MHPG levels and measures of cognitive function in children with ADHD.ResultsPlasma levels of MHPG were significantly lower in ADHD children without RD, compared with those with RD, replicating a previously published finding. Analyses in the combined sample indicated that, among children with ADHD, plasma MHPG levels were inversely associated with measures of academic achievement and verbal processing, but not parent or teacher ratings of behavior or continuous performance test measures of attention and impulsivity.ConclusionsThese data indicate that children with ADHD are not homogeneous with regard to NA function and that neurochemical variation is closely associated with differences in clinical characteristics of the children.
    Journal of the American Academy of Child & Adolescent Psychiatry 01/1998; · 6.97 Impact Factor