International Journal of Coronaviruses

International Journal of Coronaviruses

International Journal of Coronaviruses

Current Issue Volume No: 3 Issue No: 3

Review Article Open Access Available online freely Peer Reviewed Citation Provisional

Impact of COVID-19 on Cognitive and Way to Resolve

1Department of Biochemistry and Molecular Biology, Jahangirnagar University, Savar, Dhaka 1342, Bangladesh.


Cognitive abilities are of immense importance for the normal life sustenance of a human being. As cognitive impairment ensues, the living caliber declines. Among multiple factors, the current epidemic coronavirus diseases 2019 (COVID-19) has been implicated in worsening cognitive performance of the COVID-19 sufferers. Present article pinpoints the etiology and patho physiology as well as recommendations to overcome the COVID-19 led cognitive decline.

Author Contributions
Received 30 Oct 2021; Accepted 10 Nov 2021; Published 20 Nov 2021;

Academic Editor: Raul Isea, Fundación Instituto de Estudios Avanzados - IDEA, Hoyo de la Puerta, Baruta.

Checked for plagiarism: Yes

Review by: Single-blind

Copyright ©  2021 Mohammad Azizur Rahman, et al.

Creative Commons License     This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Competing interests

The authors have declared that no competing interests exist.


Mohammad Azizur Rahman, Nabidur Rahman (2021) Impact of COVID-19 on Cognitive and Way to Resolve . International Journal of Coronaviruses - 3(3):16-19.

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DOI 10.14302/issn.2692-1537.ijcv-21-4007


Among the grave concerns of COVID-19, the cognitive issue is foremost. Most of the COVID-19 survivors are either sufferers of cognitive impairment or remain vulnerable to the same as their short- or long-term consequences. Thus, the reasons behind this impediment should be delved out and appropriate recommendations should be formulated to save the global innumerable populace. In this context, the present study reports the cognitive impairments of the COVID-19 sufferers, the etiopathology, pathomechanism and putative recommendations.

Cognitive Performance

Cognitive performance comprises a number of abilities, including but not limited to, attention and thinking, listening and understanding, viewing and judging, learning and memory, reasoning and problem solving, justifying and decision making, as a whole, mental well being 1. Among different organs of the body, the central nervous system (CNS) is intricately linked with cognitive performance of a person 2. Any perturbation of the CNS affects the organismal cognitive performance 2. Though all of the cognitive attributes might not be affected equally, impairment of one type influences other, albeit modifies the normalcy 3. Recently, this type of induced cognitive impairment have been noticed in the COVID-19 sufferers 3.


Epidemic coronavirus diseases 2019 (COVID-19) has taken a heavy toll worldwide. Caused by the severe acute respiratory distress syndrome coronavirus serotype 2 (SARS CoV-2), COVID-19 affects mainly the respiratory system 4. Unfortunately, the entry route of SARS CoV-2, the angiotensin converting enzyme 2 receptor (ACE2R), abounds in the CNS and is a haven for this virus 4. Consequently, the COVID-19 patients co-manifest CNS abnormalities along with respiratory anomalies 4. As the CNS becomes affected, associated cognitive functions become disrupted 4. In this way, the secondary complications of the COVID-19 patients has been the deranged cognitive attributes that warrant adequate withstanding and management strategy.

COVID-19 and Deranged Cognition – the Achilles Heel

The “brain fog”, manifested through cognitive deficit are the etiological and patho-physiological resultants COVID-19. Following etiological and patho-physiological concerns could be attributed to this muddle.

ACE2 Overexpression

COVID-19 patients exhibit hyper expression of the ACE2 receptor that welcome the invading SARS-CoV-2 exceedingly 4, 5. Later on, pro-inflammatory cytokine led “cytokine storm” cripples both the respiratory system and CNS. Deranged CNS can hardly afford cognitive performance 4, 5. Shockingly, hippocampus and temporal lobes, the brain regions involved in memory and cognition, express ACE2 receptors that only worsen the cognitive level of the COVID-19 sufferers 4, 5.


SARS-CoV-2 led direct neurotoxicity vandalize the neurogenesis, synaptic plasticity, neurotransmission that are the neuropsychiatric hallmarks of cognitive decline 4, 5, 6.

Hypoxic-Ischemic Brain Injury

Depleted supply of oxygen to the CNS due to pulmonary debility attenuate CNS performance 7, 8. Besides, cerebrovascular injury and bursting of pro-inflammatory cytokines scars the CNS. Also, ischemic brain damage and stroke are seminal hallmarks of dementia and cognitive impairment 7, 8.

Neurovascular Dysfunction

Blood brain barrier (BBB) and endothelial dysfunction leading to cerebral microvascular damage propensities SARS-CoV-2 malediction, otherwise accentuates cognitive malfunction 9, 10.


Cognitive decline in COVID-19 patients are co-morbid expression of multiple pathophysiological symptoms 11. Besides, pre-existing cognitive decline associated with dementia and Alzheimer’s disease (AD) had been found to be overly diminished in COVID-19 sufferers 12. Diabetes and hypertenstion are among the modifiable co-morbidities of COVID-19 and cognitive decline. Alzheimer’s disease (AD), the most common form of dementia, has been reported to be interlinked with COVID-19 14, 15, 16, 17, 18.


People suffering from cognitive impairments during COVID-19 crises,

1. should be checked through COVID-19 tests.

2. should have adequate behavioral support.

3. should be supplied with medication that minimizes the consequences of neurovascular injury.

National and international health care professionals should formulate state of the art guidelines to lower the burden of cognitively impaired persons.


COVID-19 has plagued the global humanity, especially those who are already cognitively impaired. Even, de novo cognitive impairments have been detected among the COVID-19 sufferers. Immediate measures against COVID-19 led cognitive impairment could reduce global economic burden. Further studies are called for withstanding this global crisis.


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