Neurocognitive disorders -- A psychological approach to diagnosis: Using the ICD-11 as a framework

The 11th revision of the International Classification of Diseases (ICD-11) has substantially changed the classification of neurocognitive disorders. This chapter introduces the interface between the psychological and neurological components of neurocognitive disorders. The ICD-11 defines neurocognitive disorders as primary clinical deficits in neurocognitive functioning that are acquired rather than developmental. Neurocognitive disorders are conceptualized using psychological principles while integrating information about neurological processes involved in their etiology and associated impairment. Their assessment involves the integration of neuropsychological as well as social, cultural, and historical information. The chapter provides the elements of a psychological approach, including psychological models and recommendations for psychological assessment for neurocognitive disorders. It discusses presentations and symptom patterns, specifiers and subtypes, boundaries with normality, differential diagnoses, co-occurring disorders, developmental course, cultural and contextual considerations, and gender-related features.