Objectives: Anosognosia for motor impairment is a complex syndrome that can manifest itself under different forms, guiding patients’ behavior and task decisions. However, current diagnostic tools tend to evaluate only more explicit aspects of anosognosia (asking the patients about their motor abilities) and fail to address more subtle features of awareness. We have developed a new assessment measure, the ECT (Errand Choice Test), where patients are asked to judge task difficulty rather than estimate their own impairment. Methods: We assessed awareness in a group of 73 unilateral left- and right-brain damaged (30 LBD and 43 RBD, respectively) patients by means of the VATAm, which explicitly requires them to evaluate their own motor abilities, and the ECT. A control group of 65 healthy volunteers was asked to perform the ECT under two conditions: Current condition (i.e., using both hands) and Simulated conditions (i.e., simulating hemiplegia). Results: A total of 27% of the patients showed different performance on the VATAm and ECT, 21% of the patients showing lack of awareness only on VATAm and 6% only on ECT. Moreover, despite the ECT identified a higher frequency of anosognosia after RBD (33.3%) than LBD (27.6%), this hemispheric asymmetry was not significant. Remarkably, anosognosic patients performed very similarly to controls in the “current condition”, suggesting that anosognosic patients’ ability to perceive the complexity of each task per se is not altered. Conclusion: Different methods may be able to tackle different aspects of awareness and the ECT proved to be able to detect less evident forms of awareness. (JINS, 2018, 24, 45–56)

This paper discusses the definition of the state space and corresponding choice sets that figure in the theory of decision making under uncertainty. It elucidates an approach that overcomes some conceptual difficulties with the standard models and accommodates a procedure for expanding the state space in the wake of growing awareness.

Neurological patients can be entirely unaware of their disease; this phenomenon is called anosognosia and it has been shown in different sensory-motor and cognitive domains. Lack of awareness has been investigated in Alzheimer's disease (AD) and within different domains of it. In the present article we review the literature on anosognosia for AD that had been indexed on the Medline database until the end of 2004. Historical introduction to the subject is followed by a brief description of the anatomy and clinical characteristics of AD. An analysis of a number of studies that focus on the relationship between anosognosia and AD then follows. This review shows that anosognosia is typical in AD, compared with other types of dementia, and it is a distinctive feature in the most severe cases and particularly in the beginning phases of illness. From an anatomical point of view, anosognosia seems to be strictly connected to frontal lobe areas; in fact, patients with anosognosia and AD show a reduction of cerebral haematic flow in the frontal regions, as well as deficits of executive functions and extrapyramidal signs. Interestingly, co-occurring depression could be interpreted as an adaptive behavior to counter the effects of perceived loss of cognitive abilities. Finally, self-awareness in AD could have some common mechanisms with auto-monitoring in schizophrenia.