Validity and utility of Hierarchical Taxonomy of Psychopathology (HiTOP): I. Psychosis superspectrum

The Hierarchical Taxonomy of Psychopathology (HiTOP) is a scientific effort to address shortcomings of traditional mental disorder diagnoses, which suffer from arbitrary boundaries between psychopathology and normality, frequent disorder co‐occurrence, heterogeneity within disorders, and diagnostic instability. This paper synthesizes evidence on the validity and utility of the thought disorder and detachment spectra of HiTOP. These spectra are composed of symptoms and maladaptive traits currently subsumed within schizophrenia, other psychotic disorders, and schizotypal, paranoid and schizoid personality disorders. Thought disorder ranges from normal reality testing, to maladaptive trait psychoticism, to hallucinations and delusions. Detachment ranges from introversion, to maladaptive detachment, to blunted affect and avolition. Extensive evidence supports the validity of thought disorder and detachment spectra, as each spectrum reflects common genetics, environmental risk factors, childhood antecedents, cognitive abnormalities, neural alterations, biomarkers, and treatment response. Some of these characteristics are specific to one spectrum and others are shared, suggesting the existence of an overarching psychosis superspectrum. Further research is needed to extend this model, such as clarifying whether mania and dissociation belong to thought disorder, and explicating processes that drive development of the spectra and their subdimensions. Compared to traditional diagnoses, the thought disorder and detachment spectra demonstrated substantially improved utility: greater reliability, larger explanatory and predictive power, and higher acceptability to clinicians. Validated measures are available to implement the system in practice. The more informative, reliable and valid characterization of psychosis‐related psychopathology offered by HiTOP can make diagnosis more useful for research and clinical care.     

Affective and Personality Characteristics in Function of Nightmare Prevalence, Nightmare Distress, and Interference Due to Nightmares.

This study analyzes the relationships among nightmare frequency, nightmare distress, and interference due to nightmares, sleep quality, psychopathology (anxiety and depression), and personality (neuroticism, psychoticism, and boundaries). The nightmare parameters were evaluated with the Nightmare Frequency Questionnaire (B. Krakow et al., 2000; see also record 2000-16731-002), the Nightmare Distress Questionnaire (K. Belicki, 1992b; see also record 1993-08389-001), and the Nightmare Effects Survey (Krakow et al., 2000). The sample was composed of 147 healthy students. The results demonstrated that the 2 measurements of distress (subjective distress associated with nightmares and, especially, deterioration of psychosocial functioning) were the dimensions that best related to the variables studied, although the relationships were modulated by nightmare frequency. The parameter of nightmare frequency was found to be useful as an indicator of certain personality characteristics rather than psychological perturbation. Having nightmares on a weekly basis was strongly associated with depressed mood. The knowledge about these relations is relevant not only theoretically but also as a practical guide. (PsycINFO Database Record (c) 2010 APA, all rights reserved)