Electroencephalogram measured functional connectivity for delirium detection: a systematic review

Angelica Hanna; Jeffrey Jirsch; Claude Alain; Sara Corvinelli; Jacques S Lee

doi:10.3389/fnins.2023.1274837

Electroencephalogram measured functional connectivity for delirium detection: a systematic review

Front Neurosci. 2023 Nov 16:17:1274837. doi: 10.3389/fnins.2023.1274837. eCollection 2023.

Authors

Angelica Hanna^{1

2}, Jeffrey Jirsch^{1

3}, Claude Alain^{4

5

6

7}, Sara Corvinelli^{2

4}, Jacques S Lee^{1

2

4}

Affiliations

¹ Department of Medicine, University of Toronto, Toronto, ON, Canada.
² Schwartz/Reisman Emergency Medicine Institute, Sinai Health System, Toronto, ON, Canada.
³ Division of Neurology, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.
⁴ Institute of Medical Science, University of Toronto, Toronto, ON, Canada.
⁵ Rotman Research Institute Baycrest, Toronto, ON, Canada.
⁶ Music and Health Research Collaboratory, Faculty of Music, University of Toronto, Toronto, ON, Canada.
⁷ Department of Psychology, University of Toronto, Toronto, ON, Canada.

Abstract

Objective: Delirium is an acute alteration of consciousness marked by confusion, inattention, and changes in cognition. Some speculate that delirium may be a disorder of functional connectivity, but the requirement to lay still may limit measurement with existing functional imaging modalities in this population. Electroencephalography (EEG) may allow for a more feasible approach to the study of potential connectivity disturbances in delirium. We conducted a systematic review to investigate whether there are EEG-measurable differences in brain functional connectivity in the resting state associated with delirium.

Methods: Medline, PubMed, PsychInfo, Embase and CINAHL were searched for relevant articles containing original data studying EEG functional connectivity measures in delirium.

Results: The search yielded 1,516 records. Following strict inclusion criteria, four studies were included in the review. The studies used a variety of EEG measures including phase lag index, coherence, entropy, shortest path length, minimum spanning tree, and network clustering coefficients to study functional connectivity between scalp electrodes. Across connectivity measures, delirium was associated with decreased brain functional connectivity. All four studies found decreased alpha band connectivity for patients with delirium. None of the studies directly compared the different motor subtypes of delirium.

Significance: This systematic review provides converging evidence for disturbances in oscillatory-based functional connectivity in delirium.

Keywords: EEG; delirium; electroencephalography; functional connectivity; review.

Publication types

Review

Grants and funding

The author(s) declare that no financial support was received for the research, authorship, and/or publication of this article.