‘And You? What Do You Think Then?’ Taking Care of Thought and Reasoning in Intellectual Disability

Intellectual disability is a frequent but still ill-defined condition. This encompasses individuals with heterogeneous cognitive profiles who are included in a same diagnostic category, on the basis of (1) an IQ score below approximately 70 and (2) a clinical assessment of deficits in adaptive functioning. In the new Diagnostic and Statistical Manual of Mental Disorders (DSM-5), the core deficits of intellectual functioning include the ability to reason, plan, solve problems, think abstractly, comprehend complex ideas, learn academic skills, and learn from experience. Although each of these complex abilities could be analysed through both specific neuropsychological tasks and qualitative ecologically sound methods, the assessment of intellectual functioning is still centred on IQ. In recent years, there has been considerable debate as to whether a general mental function such as intelligence can map onto measures drawn from statistical analyses on the subtests concurring to IQ or, whether it should be better grounded onto the findings of developmental psychology and neuropsychology. It has been pointed out that there are several types of intelligent thinking (Gardner, 1999; Sternberg, 1985), and that acting purposefully, monitoring behaviour, planning and organising activities, are important cognitive functions that are not tapped by psychometric intelligence tests (Ardila, 1999; Fiorello et al., 2007; Greenspan & Woods, 2014; Salvador-Carulla & Bertelli, 2008).