Genetics, development of tasks and paradigms for neuroimaging, and conceptual/interpretative issues are leitmotifs in the review of neuroimaging applications in child psychiatry. Clearly, future research will draw on the rapid developments in genetics and seek to integrate genetic and neuroimaging methods. The readers will find in this section two chapters on genetics. In Chapter 18, Vandenbergh describes the techniques and methods of molecular genetics. These techniques may enable researchers to identify genes underlying neuroimaging phenotypes and playing a role in brain function. In Chapter 19, Pauls discusses specific issues in the genetic study of complex neurobehavioral conditions and stresses the need for a developmental focus in this work.

A conceptual framework for viewing neuroimaging studies of childhood disorders is provided by Müller and Courchesne (Chapter 20), who bring development to the forefront in their discussion of plasticity and its potentially detrimental, as well as beneficial, effects. Models of the range of developmental paths from neuropathology to behavioral outcomes, and implications for the design and interpretation of imaging studies, are highlighted.

Finally, the need for well-validated neuropsychologic tools for use with functional neuroimaging is addressed with two chapters on the Cambridge Neuropsychological Testing Automated Battery (CANTAB), which may serve as a model for task and paradigm development. In Chapter 21, Lee and his colleagues describe the development of this instrument and its utility in functional neuroimaging.