The top tweeted terms are the trending industry discussions happening on Twitter by key individuals (influencers) as tracked by the platform.

1. Stroke– 88 mentions

Links between Covid-19 and stroke, drugs reducing strokes or deaths, and real accounts of unseen symptoms after a stroke, were popularly discussed topics in Q4 2020. According to a discussion shared by Teshamae Monteith, a neurologist from the University of Miami, the pattern of brain recovery in patients after a stroke whether due to Covid-19 or other reasons did not differ much.

The phenomenon related to long haul Covid-19 infection or post-Covid cognitive syndrome are not completely understood and other problems related to Covid-19 such as respiratory complications, heart failure, and multiple organ damage limit the person’s ability to participate in rehabilitation programmes.

The term also trended with regards to a research on Ticagrelor (Brilinta) added to Aspirin to be superior to Aspirin alone in stroke reduction or death in patients with ipsilateral atherosclerotic stenosis at 30 days, according to an article shared by Daniel Vela-Duarte, a vascular neurologist. The study noted that in patients with a transient ischemic attack or minor ischemic strokes, those with ipsilateral atherosclerotic stenosis of cervicocranial vasculature had the highest risk of recurrent vascular events.

Other discussions around stroke involved Dr Nick Ward’s, a professor of clinical neurology and neurorehabilitation, tweet on Paul Mylrea’s story on having experienced potentially fatal hidden symptoms after a stroke. Paul Mylrea shared his Covid-19 related stroke and subsequent online cognitive rehabilitation experience with BBC Medical Editor Fergus Walsh.

Covid-19 is much more than just a respiratory disease and causes several types of neurological problems. People suffering with mild Covid-19 symptoms may also experience persistent cognitive impact of the infection such as fatigue, anxiety, and delirium.

2. Hippocampus – 82 mentions

Reasons that cause a mind-wandering state, the hippocampus building memories of distant events, and links between time cells and episodic memory, were popularly discussed during the quarter. According to a research shared by Masud Husain, a professor of neurology and cognitive neuroscience at the University of Oxford, a mind-wandering state is triggered by hippocampal sharp wave-ripples in which thoughts arise spontaneously, independent from constraints and intentions.

Hippocampus was also mentioned in another tweet by Prof Hugo Spiers, a professor of cognitive neuroscience at the University College of London (UCL), which suggested the role of hippocampus in forming narrative memories across distant events. The functional neuroimaging suggested that the hippocampus may have a role in integrating different distant events in one’s memory to form a larger coherent narrative.

The term also trended with respect to time cells in the human hippocampus and entorhinal cortex supporting episodic memory, according to an article shared by Earl K Miller, a professor of neuroscience in the Massachusetts Institute of Technology (MIT). The stability of the time signal offered by the time cells, or the neurons in the hippocampus and entorhinal cortex, during encoding affects the ability to temporarily order memories at the time of retrieval.

3. Dementia – 68 mentions

Delirium increasing the risk of future cognitive decline and dementia, and the association between sports-related head injuries and dementia, were popularly discussed in Q4. According to a research retweeted by Tom Pollak, a psychiatrist at the King’s College London, delirium increases the risk of future cognitive decline and dementia, and greater exposure with delirium is associated with worse cognitive outcomes. The study revealed that 82 out of the 205 participants, that is, 40% developed delirium in the hospital. Furthermore, out of the one-year data available for 173 patients, 18 developed dementia while 38 had died.

Dementia was also discussed with regards to sports-related injuries and dementia, according to an article shared by Alan Carson, a consultant neuropsychiatrist at NHS Lothian. The article described an increased risk of dementia caused by head injuries in rugby and football players. Approximately 50% of the former rugby players suffered from various neurological complications such as post-concussion syndrome and epilepsy which may lead to dementia, the article noted.

Forensic pathologists such as Dr Bennet Omalu have further established the link between recurrent knocks to the head and chronic traumatic encephalopathy (CTE), a progressive degenerative disease of the brain, identified in American football players. The article also emphasised the need for sports unions to implement injury prevention and treatment measures based on the latest research and evidence.

The term also trended with regards to Jonathan Schott, a neurologist at the University College London Hospitals (UCLH), pointing towards how the media has chosen to report on the association between head injuries and dementia in sports such as football and rugby, but continues to laud the violence and injuries caused in the sport of boxing.

4. Diagnosis- 53 mentions

The severity of Covid-19 symptoms, migraine diagnosis, and confusing concussion to be a diagnosis than a symptom, were popularly discussed in the fourth quarter of the year. According to an article shared by Dr Sanjay Gupta, an associate professor of neurosurgery at the Emory University Hospital, Covid-19 symptoms generally show up after days since its diagnosis, thereby requiring hospitalisation. Referring to President Trump being hospitalised on the fourth day, the influencer added, that it meant that he would have been significantly exposed to the virus and that he would have been infected much earlier.

Diagnosis also trended in a discussion by Lauren Doyle Strauss, a paediatric neurologist at the Brenner Children’s in Winston-Salem, North Carolina, who shared an article on how paediatric migraine should be treated. She stressed on the increased involvement of the paediatric patient and their parents during the treatment to understand more about the patient’s experience.

The term was also discussed by David Sharp, a consultant neurologist based at Imperial College London, who tweeted on how the term concussion is confused to be a diagnosis than being a symptom. For example, just like a chest pain is a symptom for which a treatment cannot be guessed, but an underlying cause has to be deduced. Likewise, concussive symptoms need to be understood to treat it conclusively. Some experts believe that that the term concussion should be replaced with traumatic brain injury (TBI) to understand the severity and likelihood of consequences.

5. Depression – 49 mentions

Fake statistics on rising suicide cases in the UK during the coronavirus pandemic as against more evidence on depression and anxiety, and signs of seasonal depression, were popularly discussed during the fourth quarter of 2020. According to an article shared by Jon Roiser, a professor of neuroscience and mental health at the UCL Institute of Cognitive Neuroscience, there have been abundant tweets of fake data around a 200% rise in suicides in the UK caused due to the lockdowns during the pandemic. However, although there was no evidence to support the rise in suicide numbers, health authorities realise the importance of being vigilant in the months ahead.

The term also trended with respect to subtle signs that may indicate that one maybe suffering with seasonal depression, according to an article shared by Dr Lawrence Robbins, a neurologist from Riverwoods, Illinois. According to the author, seasonal depression generally starts and ends during the same time of the year, particularly at the beginning of fall and persisting through winter.

The decreased daylight during the fall is generally perceived to trigger symptoms of seasonal affective disorder (SAD). The lack of daylight derails the human biological clock, also known as  circadian rhythm, which results in mood disorders.