Pandemic-induced ‘brain fog’ is result of cognitive overload

New working environment may be mentally tiring as we can do fewer things on autopilot

If you’re finding it hard to focus, remember things or make decisions at work, relax, you’re not losing the plot. More than likely you are suffering from pandemic-induced brain fatigue which makes it difficult to think straight.

Numerous worker surveys have been conducted since the lockdown began and there has been a noticeable shift in tone in the recent ones. In short, the novelty value of working from home has worn off and tiredness, difficulty concentrating and mental health issues have all moved centre stage.

Research published by Laya Healthcare in September showed 39 per cent of Irish workers were struggling with everyday life. More than 90 per cent were experiencing a rise in anxiety levels while 30 per cent were suffering from loneliness and isolation. One in 10 have sought help for mental wellbeing issues.

With Covid, however, everything is 'new', meaning we can draw less on our stored experience and do fewer things on autopilot. This is mentally tiring

The human brain is phenomenally resilient but it gets tired and over the last nine months, it has been on the equivalent of a processing marathon. There has been a tsunami of information and conflicting advice to sift through while trying to keep work and domestic life ticking over against a backdrop of health fears and job worries.


Anecdotally at least, brain "fog" is a big part of the pandemic experience for many and Dr Christian Jarrett, psychologist and deputy editor of Psyche magazine, has turned to science to explain why. Specifically, he has tapped into cognitive load theory to throw light on why Covid-19 is messing with our minds.

The theory was developed by Australian educational psychologist Prof John Sweller who published a paper on the topic in 1988. It characterises the mind as an information processing system and its cognitive load is the amount of information the working memory can hold at any one time. The human brain can process large amounts of stored information (stuff we already know) but only small amounts of new data and most people can retain only four "chunks" of information in their working memory at the one time.

“When we’re working on a problem, especially an unfamiliar one, we depend on our working memory, which is very limited,” Jarrett says. “The less familiar you are with a task, the more you depend on your working memory to help juggle the relevant information. In contrast, when you’re an expert, most of what you need to know is stored in your long-term memory and you can complete the task on autopilot.”

Mentally tiring

With Covid, however, everything is “new”, meaning we can draw less on our stored experience and do fewer things on autopilot. This is mentally tiring.

“Take a work meeting,” Jarrett says. “Before, you would just have turned up and joined in the discussion but now, if you’re working remotely you have to fire up your video-conferencing software, worry about your wifi, adjust your communication to the time lag and so forth.

“The same applies to domestic challenges, like ordering your groceries online instead of shopping in person,” he says. “These adaptations force you out of autopilot and draw on your limited working memory capacity. In the jargon of cognitive load theory, the intrinsic cognitive load of much of what you do has increased. You’re spending more of your life having to think deliberately and consciously, more like a novice than expert, which is exhausting in itself.”

Compounding the problem of disrupted mental function is the impact of emotions on information processing.

Put extra effort into stress management so that your working memory isn't constantly overloaded by worry

“When you’re anxious, this is known to reduce working memory capacity, thus making it more difficult to work through any mental problem that requires conscious problem-solving, making it tricky to work through maths questions or compose a coherent sentence,” Jarrett says.

Adding to the cognitive overload are distractions not related to the task in hand. For example, worrying about a broken washing machine or trying to tune out someone else’s work conversation.

“What’s happening now is that disruptions to life caused by the pandemic are forcing you to draw on your limited working memory capacity more often, at a time when – if you’re more stressed and your anxiety levels are raised or you’re juggling multiple tasks and commitments – you have diminished working memory capacity. It’s the worst of both worlds and another reason why you’re feeling mentally drained,” Jarrett says.

Coping strategies

With Christmas break on the horizon, most people will have breathing space from work. It’s welcome chill time but it’s also an opportunity to think about coping strategies for the months ahead especially if a post-Christmas Covid spike results in another lockdown.

Planning and self-discipline are key to coping, Jarrett says, and central to this is establishing and mastering new routines so you’re not wasting valuable mental energy on ordinary tasks. Also, make a concerted effort to limit distractions by only doing one thing at a time.

This means not having the radio or television on while you’re working or constantly checking your phone while doing homework with the kids or cooking dinner.

“Put extra effort into stress management so that your working memory isn’t constantly overloaded by worry,” Jarrett says. “This means eating well, exercising and establishing a predictable bedtime routine and finding time for activities that relax you.

“As far as your situation allows, work out contingency plans for different aspects of your life. Putting realistic preparations in place for feared scenarios can be a great anxiety reliever. Also, give your brain a break from the pandemic updates and doom scrolling.”

Christian Jarrett’s book Be Who You Want: Unlocking the Science of Personality Change will be published in 2021