We need all the cognitive reserve we can muster

What will the world look likein 50 years? Amid all the technological advancements, it is not hard to imagine that it will look radically different.

In a much shorter span of time, we have developed electric vehicles which can (theoretically) drive themselves, smartphones that are literally thousands of times more powerful than some of the most advanced home computers in the 1990s, and artificial intelligence entities that threaten the existence of many traditional jobs.

Whether further advancements will result in a techno-utopia or dystopia, society’s increasing reliance on, and addiction to, electronic media is a problem when it comes to the brain.

Outsourcing cognitive function to a device means that we are not exercising our brains in the way they are designed.

Although it is a not a medical diagnosis, the term ‘digital dementia’ is often used to describe this degradation of brain function. And there are concerns that the use of electronic devices might lead to significantly increased rates of clinical dementia later in life.

Given that almost everyone under a certain age engages regularly with technology, this is not a trivial issue. In the short to medium term, we may see reduced attention spans, as well as memory impairment, plus a reduced ability to problem solve (if the answer to a problem is easily available online, why would we bother to think it through?).

Scrolling is the antithesis of sustained attention, with your mind constantly drawn to the next tantalising thing you may see. We are also far less likely to commit something to memory if we don’t pay attention to it, and if we don’t need to because the information is (again) available online. Remember that the brain is a muscle and unless you are regularly using these cognitive skills, they will deteriorate.

When it comes to dementia risk, one concern about all the outsourcing of cognitive function is that it will reduce so-called cognitive reserve. This term effectively denotes your ability to function despite damage to the brain – whether that be due to the accumulation of amyloid and tau in Alzheimer’s disease, reduced blood supply due to vascular problems, or some other pathology.

The higher your reserve, the more can go wrong with your brain before you develop symptoms. We know that higher levels of education, having a job that is or was cognitively challenging, and engaging in leisure pursuits later in life all increase cognitive reserve and are associated with a reduced risk of dementia.

Despite the above concerns, not all research backs up the idea of digital dementia. An analysis of all the data (looking at more than 400,000 people in studies) in 2025 did not show a negative association with the use of technology and later dementia development. Rather, it suggested a possible benefit.

But only people over 50 were included in the research. Perhaps then their brains had had enough time without technology to already have good cognitive reserve.

Also, the study cannot prove that the use of technology caused the benefit, only that it was associated. Maybe those using it were more inclined to do so because of better underlying brain function then.

Until proven otherwise, I think we must assume there is a brain danger of overuse of technology. My advice would be to: think first and have technology augment your thinking, rather than skipping the initial effort: limit screen time; and remember that your brain did not evolve with technology in mind.

 Kailas Roberts is a psychogeriatrician and author of Mind Your Brain: The Essential Australian Guide to Dementia, available at bookstores and online. Visit yourbraininmind.com or uqp.com.au