Article

Volumetric Neuroimaging and Low-Dose Early-Life Exposures: Loose Coupling of Pathogenesis-Brain-Behavior Links

Harvard University, Cambridge, Massachusetts, United States
NeuroToxicology (Impact Factor: 3.38). 09/2005; 26(4):565-72. DOI: 10.1016/j.neuro.2005.01.002
Source: PubMed

ABSTRACT

The interface of developmental neuroimaging with developmental neurotoxicology can, broadly speaking, address two complementary concerns. The first is to study the impact of specific exposures on brain development. The second is to study known neurobehavioral disorders with an eye to discerning toxicological contributions to pathogenesis. Pathogenesis targets brain based upon physical properties (receptors, growth factors, etc.) while behavior is modulated by regional and neural systems alterations. The distribution of pathogenesis-brain relationships overlaps only partially with that of brain-behavior relationships. The goal of this paper is to highlight methodological issues involved in designing and interpreting volumetric neuroimaging studies in the light of this loose coupling.

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Available from: David A Ziegler
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    • "Overt toxicity is identified relatively rarely and is usually the consequence of high-level exposure. However, developmental neurotoxicity testing (DNT) studies face the challenge of assessing subtle effects caused by chemicals present at relatively low concentrations (Herbert and Ziegler 2005; Winneke 2011; Birnbaum 2012). Smaller effects that fall outside the definition of clinical abnormality typically require relatively large studies in which specific functional domains are assessed using objective instruments. "
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