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Social inappropriateness in neurodegenerative disorders

Published online by Cambridge University Press:  10 July 2017

Philippe Desmarais ,
Krista L. Lanctôt ,
Mario Masellis ,
Sandra E. Black  and
Nathan Herrmann
Philippe Desmarais*
Affiliation:
Geriatric Psychiatry, Sunnybrook Health Sciences Centre, Toronto, Canada Cognitive & Movement Disorders Clinic, Sunnybrook Health Sciences Centre, Toronto, Canada L.C. Campbell Cognitive Neurology Research Unit, Sunnybrook Health Sciences Centre, Toronto, Canada Hurvitz Brain Sciences Program, Sunnybrook Research Institute, Toronto, Canada
Krista L. Lanctôt
Affiliation:
Geriatric Psychiatry, Sunnybrook Health Sciences Centre, Toronto, Canada Hurvitz Brain Sciences Program, Sunnybrook Research Institute, Toronto, Canada Department of Psychiatry, University of Toronto, Toronto, Canada
Mario Masellis
Affiliation:
Cognitive & Movement Disorders Clinic, Sunnybrook Health Sciences Centre, Toronto, Canada L.C. Campbell Cognitive Neurology Research Unit, Sunnybrook Health Sciences Centre, Toronto, Canada Hurvitz Brain Sciences Program, Sunnybrook Research Institute, Toronto, Canada Division of Neurology, Department of Medicine, University of Toronto, Toronto, Canada Institute of Medical Science, University of Toronto, Toronto, Canada
Sandra E. Black
Affiliation:
L.C. Campbell Cognitive Neurology Research Unit, Sunnybrook Health Sciences Centre, Toronto, Canada Hurvitz Brain Sciences Program, Sunnybrook Research Institute, Toronto, Canada Division of Neurology, Department of Medicine, University of Toronto, Toronto, Canada Institute of Medical Science, University of Toronto, Toronto, Canada
Nathan Herrmann
Affiliation:
Hurvitz Brain Sciences Program, Sunnybrook Research Institute, Toronto, Canada Department of Psychiatry, University of Toronto, Toronto, Canada Lewar Chair in Geriatric Psychiatry, Department of Psychiatry, Sunnybrook Health Sciences Centre, Toronto, Canada
*
Correspondence should be addressed to: Philippe Desmarais, Cognitive & Movement Disorders Clinic, Sunnybrook Health Sciences Centre, 2075 Bayview Ave., Room A4-55, Toronto, Ontario M4N 3M5, Canada. Phone: 1-416-480-4551. E-mail: philippe.desmarais@sunnybrook.ca.
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Abstract

Background:

New onset of mood and behavioral changes in middle-aged patients are frequently the first manifestations of an unrecognized neurocognitive disorder. Impairment of social cognition, the cognitive ability to process social information coming from others, such as emotions, to attribute mental states to others, and to respond appropriately to them, is often at the origin of behavioral manifestations in neurodegenerative disorders.

Methods:

This paper reviews the current literature on social cognition impairment in neurocognitive disorders, particularly in prodromal stages of behavioral-variant frontotemporal dementia (bvFTD), Alzheimer's disease (AD), idiopathic Parkinson's disease (IPD), and Lewy body dementia (LBD). The concepts of social cognition will be reviewed, including its impairment and neural basis, its clinical assessment, and the different therapeutic interventions available clinically.

Results:

Socially inappropriate behaviors, such as loss of empathy, inappropriateness of affect, and disinhibition are frequently reported in prodromal bvFTD and in prodromal AD. Lack of self-control, reduced perception of social cues, such as recognition of facial emotions and sarcastic speech, and impaired Theory of Mind all contribute to the neuropsychiatric symptoms and are secondary to neurodegeneration in specific brain regions. In contrasts to bvFTD and AD, deficits in social cognition in IPD occur later in the course of the disease and are often multifactorial in origin.

Conclusions:

Through various manifestations, social inappropriateness is frequently the first clinical sign of a neurodegenerative process, especially in AD and bvFTD, years before noticeable impairment on classical neuropsychological assessment and brain atrophy on imaging.

Keywords

cognitive disordersmild behavior impairment (MBI)Alzheimer's disease (AD)mild cognitive impairment (MCI)frontotemporal dementia (FTD)
Type
Review Article
Information
International Psychogeriatrics , Volume 30 , Special Issue 2: Mild Behavioral Impairment , February 2018 , pp. 197 - 207
Copyright
Copyright © International Psychogeriatric Association 2017 

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