to the Animal Models Volumes This and several other volumes in the Neuromethods series will describe a number of animal models of neu- psychiatric disorders. Because of increasing public concern over the ethical treatment of animals in research, we felt it incumbent upon us to include this general preface to these volumes in order to indicate why we think further research using animals is necessary and why animal models of psychi- ric and neurologic disorders, in particular, are so important. We recognize that animals should only be used when suitable alternatives are not available. We think it self-e- dent, however, that humans can only be experimented upon in severely proscribed circumstances and alternative pro- dures using cell or tissue culture are inadequate in any models requiring assessments of behavioral change or of complex in vivo processes. However, when the distress, discomfort, or pain to the animals outweighs the anticipated gains for human welfare, then the research is not ethical and should not be carried out.

Ethics of Animal Models of Neurological Diseases.- Animal Models of Alzheimer's Disease.- Animal Models of Huntington's Disease.- Rodent Models of Parkinson's Disease.- Primate Models of Parkinson's Disease.- Genetic Dysmyelination Models.- Nongenetic Animal Models of Myelin Disorders.- Animal Models of the Cerebellar Ataxias.- Animal Models for Lesch-Nyhan Disease.