Getting lost easily could be an early sign of Alzheimer’s - a expert neurologist reveals

Written by: Dr Dennis Chan
Edited by: Cameron Gibson-Watt

A poorer sense of direction or difficulty finding your way around places may be among the first indications that Alzheimer’s disease could affect you later on in life.

This is the preliminary result of The PREVENT project, an ongoing long-term study being carried out by experts seeking to uncover how dementia first affects the brain.

In this article, Dr Dennis Chan explains more about the findings and what it means for future Alzheimer's treatment. He also describes The Four Mountains test of spatial memory, used in the study to help experts pinpoint those in middle age at a high risk of developing Alzheimer's in later life.



Who does the study involve?

The PREVENT project, which is funded by the Alzheimer’s Society and based at Edinburgh University, aims to detect signs of Alzheimer’s in middle-aged people before symptoms appear later in life. Symptoms typically don't appear until people reach their 60s and unfortunately by this time, it has already done significant damage to the brain.


Loss of navigational skills

We usually consider Alzheimer’s to be a disease that affects memory in elderly patients. However, researchers believe that small changes begin in the brain when people are in their 40s and 50s, 10 to 15 years before symptoms arise.


The findings from the study so far suggest that middle-aged people at risk of future dementia have a poorer ability to remember spatial layouts, which might impair their navigational skills.


So, how did researchers discover this?


The Four Mountains test

The PREVENT team works with volunteers who take part in various tests. One of these is The Four Mountains test - a test developed by my collaborators based at University College London and the University of York.


The ability to recognise places and visualise them from different points of view depends on the hippocampus, a region in the brain’s temporal lobe that is affected in the earliest stages of Alzheimer's disease. The Four Mountains Test can test this ability and we have previously found that patients with established dementia perform poorly on the test. During the test, people are shown a picture of four mountains and are asked to identify the correct picture when it is shown from a different perspective.


Researchers found that those who were at a higher risk of Alzheimer's did more poorly on this test, indicating poorer spatial memory. MRI studies have also shown that these people had a smaller hippocampus, which may be due to brain degeneration.


The test can therefore provide scientists and doctors with a potentially powerful tool to identify the earliest stages of Alzheimer’s disease before people develop symptoms.


Why is it important to identify those at risk early?

There are several important reasons for this. First, in the near future we will have drugs with the ability to slow the progression of dementia and these drugs will be most effective if given in the initial stages of the disease.


Second, separate research done by myself and others has shown that higher levels of engagement in physical, intellectual and social activities can maintain brain health into late life and reduce the risk of dementia. So detecting people at high risk would allow doctors to help people implement lifestyle changes to lower the risk of future dementia.


Third, it is important to have tests that can distinguish between different causes of memory decline. While some people with mild memory impairment may have early Alzheimer’s disease, in others it is due to other causes such as anxiety, depression, poor sleep and even medications. It is critically important that any such causes be identified and addressed, and that those affected do not labour under the misapprehension that they have Alzheimer’s disease.


If you are worried about dementia and would like to speak to a specialist, visit Dr Dennis Chan's Top Doctors profile and book an appointment with him.

By Dr Dennis Chan

Dr Dennis Chan is a highly qualified neurologist with vast experience treating a range of neurological disorders including headache, Parkinson's disease, epilepsy, and multiple sclerosis. He is an internationally recognised expert in dementia, specialising in the diagnosis of Alzheimer's disease, mild cognitive impairment, and other memory disorders. His private clinics are located at Spire Gatwick Park Hospital, Spire Montefiore Hospital in Hove and The North Downs Hospital in Caterham. Dr Chan's NHS clinics in memory disorders and general neurology are held in Cambridge and Sussex.

Dr Chan qualified in medicine from the University of Cambridge. In addition to his medical degree, he holds two research doctorates. He obtained a PhD under the supervision of Professor John O'Keefe (University College London), who was later awarded the 2014 Nobel Prize in Physiology or Medicine, and an MD under Professor Rossor, Institute of Neurology, London. From 2014 - 2019 he was based at the University of Cambridge and in 2019 he moved his NHS work back to Sussex, and his academic work back to UCL.

Dr Chan's research into Alzheimer's disease has received extensive media coverage, with articles in all the leading national newspapers (including The Times, Independent, Guardian, Daily Mail, Daily Telegraph) as well as interviews on BBC national TV, the BBC Radio 4 Today programme and CBS TV in the USA. His work has been published in the top research journals including Nature and The Lancet. Dr Chan receives research grant funding from the Medical Research Council, Wellcome Trust, Alzheimer's Research UK, Alzheimer's Society, Innovate UK, and the Alan Turing Institute. His research has been extensively covered by the national and international news media. 

Dr Chan is also leading UK research into cognitive impairment (brain fog) as part of long Covid. In July 2021 he was awarded £1.2 million by the National Institute of Health Research to study and treat this problem.

Dr Dennis Chan is happy to offer virtual consultations. To request an appointment, please click the blue eConsultation button on the profile. 

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