Introduction
The coronavirus disease 2019 (COVID-19), which has affected million
people worldwide and has posed a serious health threat on a global
scale, is caused by the positive-sense, enveloped, single-stranded RNA
virus known as Severe Acute Respiratory Syndrome Coronavirus 2
(SARS-CoV-2) (1). The published evidence indicates that the virus
can enter the central nervous system (CNS) through the olfactory nerve,
most likely using axonal transport and transsynaptic transport. In
addition, the hematogenous pathway and other ways have been identified
as other ways by which the virus might enter the brain (2-4).
The effects of COVID-19 on the
brain are becoming more obvious. According to recent research, the
coronavirus may attack specific brain cells directly, decrease blood
supply to brain tissue, or cause the creation of immune chemicals that
can damage brain cells. Former studies also reported the complications
including agitation, impaired consciousness, headache, and dizziness
stemmed from COVID-19 infection (5). Thereafter recovery, alas,
suffering from few adverse effects of this infection have also been
shown, namely fatigue, anxiety, depression, and insomnia (6).
Accordingly, impediment to memory, concentration, or attention has been
reported over the acute phase, accounting for a third of participants
(7).
Of note, COVID-19, in accordance with a study carried out in Oxford
University, gives rise to shrinking the brain and diminishing grey
matter in the areas controlling memory. By comparison with uninfected
participants in this study, patients irrespective of afflicting with
mild or sever COVID-19 have been shown to have noticeably impair
episodic memory – which can be durable up to 6 months thereafter
infection, and not to be able to sustain attention over time – being
durable up to 9 months thenceforth infection. Not understanding the
mechanisms that cause these cognitive impediment notwithstanding, these
adverse events were pointed out hopefully to return predominantly to
normal in most COVID-19 patients by 6-9 months after infection (8).