Abstract
Theory of Mind (ToM) is a cognitive construct that involves different levels of complexity. Development of the different ToM skills follows an evolutionary course in line with the increasing requirements from environmental demands through childhood and adolescence to adulthood. Accordingly, ToM assessment should comprise the heterogeneity of the components – affective or cognitive – and the rising complexity of tasks according to the developmental course – first-order, second-order and higher-order beliefs. In this chapter, features of ToM assessment are presented with a compilation of the main useful tools. Furthermore, specific ToM deficits in neuropsychiatric disorders are collected. ToM impairments have been extensively studied in autism spectrum disorders and schizophrenia, but in recent years their study has been extended to many other clinical diagnoses and significant transversal problems in mental health such as suicidal behavior. As a result, this chapter outlines a comprehensive picture of ToM impairments in a broad range of neuropsychiatric disorders and the accurate assessment of the different deficits, to provide the reader an essential knowledge for understanding ToM impairments across neuropsychiatric disorders and assessment protocols in clinical practice.