Orientation and disorientation: lessons from patients with epilepsy

Abstract

Orientation in time, space, and person is a fundamental cognitive faculty and the bedrock of neurological and psychiatric mental status examination. Nevertheless, research in orientation and disorientation is neglected in both cognitive science and neuropsychiatry. Specifically, it is still unclear whether disorientations in time, space, and person represent a failure of the same system or merely share a common nomenclature and whether these three domains of orientation depend on different psychological and neural systems. Here, we analyzed descriptions of patients with specific orientation failures associated with circumscribed cortical lesions, with a primary focus on epilepsy. The form of disorientation is analyzed according to its specific domain, the underlying neuropsychiatric disorder, and its anatomical correlate. Disorientations in the different domains are classified as self-referenced (incorrect self-localization) or nonself-referenced (incorrect localization or knowledge of other places, events, and people). Analysis of the cognitive and neural systems disturbed in these patients suggests that disorientation in one or several domains may be related to a failure in a specific brain mechanism localized mostly in the right hemisphere, partially overlapping with the default mode network (mostly the medial and lateral parietal, medial temporal, and lateral prefrontal cortices), which processes essential self-related cognitive faculties such as orientation.

Keywords: Disorientation; Epilepsy; Person; Place; Self; Space; Time.