Neuroscientist Dr Adrian Owen says warning signs of dementia can surface in a person's ability to plan, multitask and control impulses many years before doctors diagnose Alzheimer's disease, sometimes as early as 14 years in advance.
Owen, who has spent more than 35 years studying the brain, described treating a businessman from south London who ran a thriving textiles firm before a brain tumour was removed. After the operation, the man began firing staff on a whim and signed a large contract with a materials supplier despite having neither the staff nor the storage space to handle the fabric, leaving material worth a fortune to rot outside his company's headquarters.
Owen also recalled a female patient in her late 60s who had also had a brain tumour removed. While sitting for a memory test, she moved her hand up his thigh toward his crotch. He gently removed her hand and asked her to concentrate on the test. "Oh, I had no idea what I was doing!" she said, before sliding her hand back up his leg minutes later.
Owen said both patients had suffered damage to the frontal lobe, the region just behind the forehead that makes up about 30 per cent of the brain's volume and controls executive function, the mental skills used to manage impulses, juggle tasks and hold information in working memory. Damage to this area can impair judgment, causing uncharacteristically rude or inappropriate behaviour, and can affect the ability to complete previously simple tasks, he said.
Career studying the brain
Owen spent much of his career at the University of Cambridge before moving to Canada in 2010 to become professor of cognitive neuroscience and imaging at the Centre for Brain and Mind at Western University. In 2006, his lab made a discovery that changed understanding of the vegetative state: when a patient believed to be entirely unaware was asked to imagine playing tennis, her brain responded as a healthy person's would, showing she was conscious. A few years later, his team showed similar patients could answer questions and communicate using only their thoughts.
Owen's lab has since completed dozens of studies on executive function, scanning the brains of thousands of people. Through the lab's digital cognitive assessment platform, Creyos, which lets researchers and clinicians use short, game-like tasks to assess memory, attention, reasoning and self-control, the brains of almost 20 million volunteers have been tested, Owen said.
A 14-year head start
Research published in the journal Alzheimer's & Dementia in 2016 found that cognitive deficits unrelated to long-term memory, such as trouble planning ahead or juggling several tasks, can emerge as many as 14 years before a formal Alzheimer's diagnosis, according to Owen. More than 100 anti-Alzheimer's drugs are currently in clinical trials worldwide, and Owen said many results suggest early intervention is most effective at slowing the disease's progression.
A study published in the British Journal of Psychiatry in 2017 recruited 30 patients with mild Alzheimer's disease and tested their ability to repeat back increasingly long sequences of numbers. Some patients were trained in "chunking," a method of breaking digits into smaller groups and spotting patterns, while others spent the same amount of time on a similar task without the method. After 18 half-hour sessions over eight weeks, the trained group significantly improved their ability to remember structured sequences, while the untrained group showed no such effect and dropped almost two points on the Mini Mental State Examination, a widely used measure of cognitive performance and a diagnostic tool for dementia, Owen said.
The memory palace technique
Owen also described the "memory palace" technique, which uses the brain's spatial navigation system, centred on the hippocampus, to mentally associate information with familiar locations such as the interior of a house. He recalled attending the Latitude Festival in 2009 to give a 45-minute talk on drugs and the brain. Immediately afterward, memory expert Richard Bowdler repeated the talk in about eight minutes, almost word for word, having heard it only once, by mentally placing concepts at locations around the festival tent, such as visualising a hippopotamus sitting on a fridge when Owen said the word "hippocampus."
Owen said turning facts into an absurd story, such as imagining posting a letter that causes a postbox to burst into flames before a milkman puts out the fire, can also help hold on to short lists, since stranger stories are harder to forget. His lab's MRI studies found these methods reduce mental load by anchoring new information to stronger neural pathways, he said.
Testing willpower with Double Trouble
Owen said loss of inhibitory control, or willpower, is another failure of executive function seen in dementia patients, as with the patient who touched him inappropriately. He described a test called Double Trouble, in which a subject must name the colour of the font used to print a colour word, such as identifying blue type spelling out the word "red." In 2023, using the Creyos platform, Owen's lab developed an algorithm to identify dementia-like cognitive impairment based on performance in two cognitive tests, including Double Trouble, which accurately spotted dementia patients more than 80 per cent of the time, according to Owen.
Lifestyle factors that affect the brain
Owen said regular aerobic exercise, such as running or cycling, has been shown to enhance frontal lobe function and improve planning ability even in older adults, by boosting blood flow to the brain and the release of brain-derived neurotrophic factor. He said sleep deprivation disrupts the dorsolateral prefrontal cortex, the region critical for planning, and can make people less able to interpret facial expressions accurately. Stress and anxiety also reduce the ability to switch between tasks, Owen said, while hunger affects the frontal lobe's ability to regulate emotions, a phenomenon he linked to the brain's immense energy demands, which account for about 20 per cent of total energy use.
Diet and daily habits
A 2016 study of 25 adults who drank grape juice daily for 12 weeks found improvements in attention, working memory, planning and driving behaviour, Owen said. A 2023 study at King's College London found some aspects of executive function were better in people who ate blueberries than in those given a placebo, with both fruits rich in flavonoids, compounds that some studies suggest can reduce inflammation and block the build-up of beta-amyloid plaques associated with Alzheimer's. Owen also said coffee in moderation, up to three or four cups a day, can improve planning and task-switching, and that simply writing a list remains one of the easiest ways to support memory and planning.
Owen's account is adapted from his book "Think Before You Think," published by Guardian Faber Publishing and due out August 13.
