Читать книгу Abnormal Psychology - William J. Ray - Страница 177

The historical considerations of psychopathology emphasized careful observation and interaction with the afflicted individuals as important methods for understanding the nature of the disorder. Based on these observations of symptoms and signs, individuals were diagnosed and classified as falling into discrete categories of disorders. This is an important level of analysis and one I will emphasize throughout this book. However, there are other levels of analysis for understanding psychopathology.

With progress in the neurosciences in general and brain imaging and genetics in particular, other levels of analysis have become possible. These new levels of analysis offer different perspectives for the field of mental illness. What seemed like discrete categories of psychopathology previously are now seen to cluster in new and different ways when considered from the standpoint of genetics. Additional groupings have emerged as scientists have considered the neural networks involved in particular manifestations of psychopathology. This has led to the realization that mental disorders can be described in both a categorical and a dimensional manner.

categorical: in psychopathology, describes the approach to determining whether a person has or does not have a disorder based on the presence or absence of a certain set of symptoms

dimensional: in psychopathology, describes the assessment of severity of a disorder on a continuum, in terms of differing degrees

As shown in the physical sciences, there are times in which a phenomenon can be described both categorically and dimensionally. For example, when water is heated, the rise in temperature can be described in a dimensional manner in terms of a certain number of degrees. However, at a critical point, the water turns to steam, which is a categorically different state from water. Likewise, a reduction in temperature changes water into a different categorical state—ice. The question for the study of psychopathological disorders is to determine the underlying dimensional changes that are associated with categorical-like transformations leading to a disordered state. Further, different underlying processes may actually allow for the presence of more than one disordered state at the same time.