EEG-based neurophysiological indicators of hallucinations in Alzheimer's disease: Comparison with dementia with Lewy bodies

Meenakshi Dauwan; Mascha M J Linszen; Afina W Lemstra; Philip Scheltens; Cornelis J Stam; Iris E Sommer

doi:10.1016/j.neurobiolaging.2018.03.013

EEG-based neurophysiological indicators of hallucinations in Alzheimer's disease: Comparison with dementia with Lewy bodies

Neurobiol Aging. 2018 Jul:67:75-83. doi: 10.1016/j.neurobiolaging.2018.03.013. Epub 2018 Mar 19.

Authors

Meenakshi Dauwan¹, Mascha M J Linszen², Afina W Lemstra³, Philip Scheltens³, Cornelis J Stam⁴, Iris E Sommer⁵

Affiliations

¹ Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, The Netherlands; Department of Clinical Neurophysiology and MEG Center, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands; Department of Neuroscience and Psychiatry, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands. Electronic address: m.dauwan-3@umcutrecht.nl.
² Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, The Netherlands; Department of Neuroscience and Psychiatry, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Alzheimer Center and Department of Neurology, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands.
³ Alzheimer Center and Department of Neurology, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands.
⁴ Department of Clinical Neurophysiology and MEG Center, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands.
⁵ Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, The Netherlands; Department of Neuroscience and Psychiatry, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Biological and Medical Psychology, Faculty of Psychology, University of Bergen, Bergen, Norway.

PMID: 29653315
DOI: 10.1016/j.neurobiolaging.2018.03.013

Abstract

We studied neurophysiological indicators of hallucinations in Alzheimer's disease patients with hallucinations (ADhall+), and compared them with nonhallucinating AD (ADhall-) and dementia with Lewy bodies (DLBhall+) patients. Thirty-six matched ADhall+ and 108 ADhall- and 29 DLBhall+ patients were selected from the Amsterdam Dementia Cohort. Electroencephalography (EEG) spectral and functional connectivity (FC) analyses (phase lag index) were performed. Quantitative and visual EEG measures were combined in a random forest algorithm to determine which EEG-based variable(s) play a role in hallucinations. ADhall+ patients showed lower peak frequency (7.26 vs. 7.94 Hz, p < 0.01), α2-and β-power, and α2-FC but higher δ-power compared to ADhall-. ADhall+ showed lower δ-power, higher β-power, and α1-FC than DLBhall+ but did not differ in peak frequency (7.26 vs. 6.95 Hz), θ- or α-power. ADhall+ patients could be differentiated from ADhall- and DLBhall+ with a weighted accuracy of 71% with α1-power and 100% with β-FC, the 2 most differentiating features. In sum, EEG slowing and decrease in α1-and β-band activity form potential neurophysiological indicators of underlying cholinergic deficiency in ADhall+ and DLBhall+.

Keywords: Alzheimer's disease; Dementia with Lewy bodies; EEG; Hallucinations; Random forest.

Publication types

Comparative Study
Research Support, Non-U.S. Gov't

MeSH terms

Aged
Aged, 80 and over
Alzheimer Disease / psychology*
Cognition / physiology
Cohort Studies
Electroencephalography*
Female
Hallucinations / diagnosis*
Hallucinations / physiopathology*
Humans
Lewy Body Disease / psychology*
Male
Middle Aged