The relationship between psychiatry and neurology, at one time unified specialties, has been problematic for well over a century. With the emergence of numerous theories of the nature of mental life and of the mind, came corresponding systems for the treatment of psychiatric disease. Most of these systems, typified in the past by psychoanalysis, seemed to have little in common with neurologic ideas about the structure and function of the brain. Freed from the archetype of the main mental disease that was the result of structural damage to the brain, syphilitic general paresis, psychiatry was able to turn to matters that were less anchored in medicine. With the emergence of a new biologic psychiatry based on neurochemistry, genetics, and functional imaging of the brain, it would seem that the gap between diseases of the mind and of the brain is closing. However, neurologists should view some of these modern ideas with at least some skepticism. For example, the observation of brain function by the use of imaging methods, and disruption of that function in disease, is not the equivalent of the disease itself and certainly cannot capture the experience through which mental disease is manifest. To dissociate an individual’s personal history and experiences, aspects of life that probably cannot be quantified or visualized, from diseases of the mind remains an artifice now, as it was in the time of the classic philosophers. This potential division between mind and brain, called “dualism,” is particularly apparent when one begins to analyze the normal stream of thought that dominates daily life rather than the disordered thoughts of mental disease states. The great Hughlings Jackson was of the opinion that the brain provides a platform for thinking but is not explanatory of it, a property of mind he termed “emergent.” This leaves open the possibility of a science of the mind that is separate from the science of the brain. Moreover, the separation of quirks of personality and character traits, probably reflecting the biologic diversity of the development of the brain, from genuine disease will remain eternally problematic. Even the margins between the disease and mental dysfunction have been disputed and have given rise to numerous “shadow syndromes” of psychologic origin that are subject to change with popular culture and fashion. This serves as an appropriate introduction to a chapter on what was formerly termed the neuroses and have been renamed.
In every society, there are many troubled individuals who are neither mentally ill nor developmentally impaired. They differ from other people in being plagued by feelings of inferiority or self-doubt, suspicion about the motives of others, low energy, inexplicable fatigue, shyness, irritability, moodiness, sense of guilt, and unreasonable worries and fears. They suffer as a result of these feelings or they behave in ways that are upsetting to those around them and to society at large. Yet none of these conditions precludes partaking in the everyday life, such as attending school, working, marrying, and raising a family. As these conditions were more carefully documented in the early part of the last century, they came to be called neuroses, and those that created societal difficulties were called psychopathies, and more recently, personality disorders and sociopathies.
The question of the purity and homogeneity of these mental states creates an ongoing polemic in psychiatry, medicine and society. The neuroses as a group appeared to be so diverse as to require subdivision in former editions of the Diagnostic and Statistical Manual of Mental Disorders (DSM) into no less than 7 different types before the term was expunged in 1980. We take a neutral position on the value of DSM not out of iconoclasm but because the definitions in that system are changed frequently, are subject to considerable controversy, and often do not accord with neurobiologic ideas of brain function. In any case, readers may wish to consult the most current DSM-5 where appropriate, to gain insight into the evolving thinking of the psychiatric community.