Neuroanatomy of impaired self-awareness in Alzheimer's disease and mild cognitive impairment

Giovanna Zamboni, Erin Drazich, Ellen McCulloch, Nicola Filippini, Clare E. Mackay, Mark Jenkinson, Irene Tracey, Gordon K. Wilcock

Research output: Contribution to journalArticle

52 Citations (Scopus)

Abstract

Introduction: Patients with Alzheimer's disease (AD) and mild cognitive impairment (MCI) may be unaware of their cognitive impairment. The neuroanatomical mechanisms underlying this symptom, termed anosognosia or impaired self-awareness, are still poorly understood. In the present study we aimed to explore the functional correlates of self-awareness in patients with MCI and AD. Methods: Fifty-one participants (17 healthy elderly, 17 patients with MCI, and 17 patients with AD), each accompanied by a study partner, took part in a functional magnetic resonance imaging (fMRI) study, in which they were presented with questions regarding themselves (Self condition) or their study partner (Other condition). The study partner was asked to complete a paper questionnaire answering the same questions so the responses of participant and study partner could be compared and "discrepancy" scores calculated for each of the 2 conditions (Self and Other). Results: Behavioural results showed that AD patients had significantly higher "Self discrepancy scores" than controls and MCI patients, whereas there were no significant differences between groups for "Other discrepancy scores" Imaging results showed a significant group-by-condition interaction in brain activation in medial prefrontal and anterior temporal regions, with AD patients showing significantly decreased activation in these regions only for the Self condition. There were no significant differences between Self and Other conditions in either control or MCI groups, suggesting that, in these groups, Self- and Other-appraisal share similar neuroanatomical substrates. Conclusions: Decreased functional activation of medial prefrontal and anterior temporal cortices is associated with impaired self-awareness in AD patients. This dysfunction, which is specific for Self- but not for Other-appraisal, may be a contributing factor to anosognosia in AD.

Original languageEnglish
Pages (from-to)668-678
Number of pages11
JournalCortex
Volume49
Issue number3
DOIs
Publication statusPublished - 1 Mar 2013
Externally publishedYes

Keywords

  • Alzheimer's disease
  • Anosognosia
  • Anterior temporal lobe
  • Medial prefrontal cortex
  • Mild cognitive impairment
  • Self-appraisal
  • Self-awareness

ASJC Scopus subject areas

  • Neuropsychology and Physiological Psychology
  • Experimental and Cognitive Psychology
  • Cognitive Neuroscience

Cite this

Zamboni, G., Drazich, E., McCulloch, E., Filippini, N., Mackay, C. E., Jenkinson, M., ... Wilcock, G. K. (2013). Neuroanatomy of impaired self-awareness in Alzheimer's disease and mild cognitive impairment. Cortex, 49(3), 668-678. https://doi.org/10.1016/j.cortex.2012.04.011