Forgetting a phone number or walking into a room and forgetting why can be a frustrating part of daily life, but a leading dementia expert says most of these so-called "brain farts" are not a sign of the disease. Professor June Andrews, professor emeritus at the University of Stirling, said the most common question she is asked is how to tell a normal memory lapse from dementia, a condition that affects almost one million Britons.
"We know that people are more afraid of dementia than they are of other serious illnesses like cancer," Andrews said. "This is especially true for middle-aged or older people. When they have a problem remembering things, they worry if it is dementia."
The good news, she said, is that most of the time it is not. Andrews outlined the key differences between ordinary confusion and potential warning signs of the disease.
Forgetting how to do things you previously could
Andrews said she often hears from people worried they cannot remember phone numbers, but that this can be normal if someone is under high stress or exhausted. Studies have shown sleep deprivation can weaken brain cells in areas involved in memory, and stress has also been found to affect the brain's memory function, particularly in middle age.
Researchers from Harvard Medical School found in 2018 that higher levels of cortisol, the body's main stress hormone, may cause the brain to shrink over time and impair memory.
A more serious sign, Andrews said, is losing the ability to do tasks previously managed with ease, whether that is everyday activities like using a phone or a skill mastered as part of a job, such as a skilled mathematician suddenly unable to add up.
"Not being able to remember 10 pages that you had read would be really serious if you were, for example, a barrister or an advocate who was going to be presenting a case in court the next day," Andrews said. "There's some jobs where it's really important and some where it doesn't matter at all. It's a change from what you used to be able to do that matters."
Being unable to recognise previously familiar faces
People may worry about dementia because they struggle to remember the names of loved ones, Andrews said, but this can be more common among people with large families and may not be a concern if someone gets a name or two "muddled up."
"The really worrying thing would be if you look at somebody in your family and you don't recognise them," she said. "If you're just confused with names it could be because you're busy, you're stressed or you've got such a big family."
Not being able to figure out where you are
Research from 2022 found Britons forget an average of 1,095 things a year, including birthdays and where they parked the car. The study of around 2,000 UK adults found people often forgot why they went to the supermarket or why they walked into a room.
According to the research charity Alzheimer's Society, being confused about a time or place is one of the most common signs of dementia. This can mean someone struggles to remember a location they have visited many times, or becomes confused about where they are.
Andrews said memory lapses that resolve quickly are less concerning than being unable to work the problem out for a long time and becoming panicked.
"I might wake up one morning in a hotel room and for a moment, I don't remember where I am," she said. "But I look around and I see where I am. I realise, oh, I woke up in a strange bed, but here I am on holiday. When someone has dementia, they can't work it out. They wake up in a strange bed and they don't recognise where they are, but they don't have the capacity to work out where they are. And that's why people with dementia often suffer from terrible stress because the world doesn't make sense anymore."
Previously simple tasks become difficult or impossible
Andrews said it is a red flag if someone struggles with mundane tasks like washing or preparing a meal. "It is very worrying if you can't use the equipment you used to be able to use and can't follow a conversation and can't follow instructions," she said.
"If you get a packet of washing powder and you think, where do I put this? Does it go in the drum or does it go in the drawer? I can't read it. Then you put it down and don't bother doing your washing because you can't work out. If you've reached that stage when you used to be able to operate the washing machine without any difficulty, then you need to go and see the doctor and say, is there something wrong with me?"
It could be a range of other problems
Andrews stressed that no single symptom should be seen as less of a concern than another, and encouraged anyone worried about their memory to speak to their GP, who can investigate a range of possible causes.
"A doctor will look for whether the person has an infection or if there's something in their blood results that's problematic, like a vitamin deficiency or a problem with their thyroid," she said. "They will also ask questions like, how are you sleeping? Are you stressed? Is there something in your life that's causing you difficulties that's psychological? And there are certain times of life when people are more likely to have that kind of difficulty with thinking, but it's caused by their life circumstance."
She pointed to bereavement and the menopause as two common examples, noting that many women going through menopause report brain fog, while grief and prolonged stress can also affect memory and concentration.
"If you've got any of the symptoms that could be dementia, the doctor will be looking to rule out other explanations," she said. "And that's why it's always a good idea to go and see a GP if you're worried about your memory."
