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Review
. 2023 Mar 20:17:1156914.
doi: 10.3389/fnins.2023.1156914. eCollection 2023.

Olfactory dysfunction: A plausible source of COVID-19-induced neuropsychiatric symptoms

Alan Pui-Lun Tai  1   2   3 , Mei-Kei Leung  4 , Benson Wui-Man Lau  5 , Shirley Pui-Ching Ngai  5 , Way Kwok-Wai Lau  1   2   3
Affiliations
Review

Olfactory dysfunction: A plausible source of COVID-19-induced neuropsychiatric symptoms

Alan Pui-Lun Tai et al. Front Neurosci. .

Abstract

Olfactory dysfunction and neuropsychiatric symptoms are commonly reported by patients of coronavirus disease 2019 (COVID-19), a respiratory infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Evidence from recent research suggests linkages between altered or loss of smell and neuropsychiatric symptoms after infection with the coronavirus. Systemic inflammation and ischemic injury are believed to be the major cause of COVID-19-related CNS manifestation. Yet, some evidence suggest a neurotropic property of SARS-CoV-2. This mini-review article summarizes the neural correlates of olfaction and discusses the potential of trans-neuronal transmission of SARS-CoV-2 or its particles within the olfactory connections in the brain. The impact of the dysfunction in the olfactory network on the neuropsychiatric symptoms associated with COVID-19 will also be discussed.

Keywords: COVID-19; nervus terminalis; neuropsychiatric symptoms; olfactory system; trans-neuronal viral transmission.

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Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

FIGURE 1
FIGURE 1
A flowchart illustrating different possible mechanisms that lead to altered functions of the limbic system and the associated neuropsychiatric symptoms in COVID-19.
See this image and copyright information in PMC

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