Category: Dementia

Normally people’s brains shrink by about 5% every decade after the age of 40 but this could be prevented.

Exercise increases brain size and so may help stop brain shrinkage with age, a study finds.

In some of the best evidence to date, exercise was shown to increase the size of the hippocampus, a brain structure critical for memory and other functions.

So far, studies have mostly shown the connection between exercise and brain size in rodents.

Shrinking brain size

Researchers followed people aged 24 to 76 for up to two years in a range of separate studies.

They looked at the effects of walking, cycling, treadmill running and general aerobic exercise.

Most people did around 2-5 sessions per week.

The results showed that left hippocampul volume was increased in people who exercised.

Dr Joseph Firth, the study’s first author, said:

“When you exercise you produce a chemical called brain-derived neurotrophic factor (BDNF), which may help to prevent age-related decline by reducing the deterioration of the brain.

Our data showed that, rather than actually increasing the size of the hippocampus per se, the main ‘brain benefits’ are due to aerobic exercise slowing down the deterioration in brain size.

In other words, exercise can be seen as a maintenance program for the brain.”

Preventing brain shrinking with age is possible

The study reviewed 14 separate clinical trials, including brain scans from 737 people.

This is some of the most definitive evidence yet published of the beneficial effects of exercise on brain health.

Normally people’s brains shrink by about 5% every decade after the age of 40.

Exercise is one of the few interventions proven to slow this process down.

The study was published in the journal NeuroImage (Firth et al., 2018).

Loss of smell is an early sign of dementia because the the olfactory bulb is one of the first brain regions to be affected by dementia.

Losing your sense of smell is an early sign of dementia, research finds.

Almost all the people in the research who could not identify any of five common smells went on to develop dementia within five years.

Those who could not name four out of five common smells, had twice the risk of developing dementia in the next five years.

Professor Jayant M. Pinto, who led the research, said:

“These results show that the sense of smell is closely connected with brain function and health.

We think smell ability specifically, but also sensory function more broadly, may be an important early sign, marking people at greater risk for dementia.”

Professor Pinto continued:

“We need to understand the underlying mechanisms, so we can understand neurodegenerative disease and hopefully develop new treatments and preventative interventions.

Loss of the sense of smell is a strong signal that something has gone wrong and significant damage has been done.

This simple smell test could provide a quick and inexpensive way to identify those who are already at high risk.”

Loss of smell and dementia study

The researchers used a tool called “Sniffin’Sticks”, which look like a normal marker pen.

They found that out of almost 3,000 people aged 57 – 85, 78.1% could identify four or five out of five of the smells.

Other studies have also shown that loss of sense of smell is linked to dementia.

It is because the part of the brain that deals with smell (the olfactory bulb) is one of the first to be affected by dementia.

Professor Pinto said:

“Our test simply marks someone for closer attention.

Much more work would need to be done to make it a clinical test.

But it could help find people who are at risk.

Then we could enroll them in early-stage prevention trials.

Of all human senses, smell is the most undervalued and underappreciated – until it’s gone.”

The study was published in the  Journal of the American Geriatrics Society (Adams et al., 2017).

Best IQ supplement for older adults with mild cognitive impairment (MCI).

Docosahexaenoic acid (DHA) — an omega-3 fatty acid — can improve IQ by 10 percent, research finds.

People in the study, who were aged over 65, were given 2g/day of DHA for a year.

A control group was given a placebo of corn oil.

The high quality study involved 240 Chinese individuals.

Their IQ and other measures of cognitive function were tested after 6 and 12 months.

The study’s authors explain the results:

“…oral DHA supplementation (2 g/d) for 12 months beneficially affected global cognitive function, specifically participants’ performance on the Information and Digit Span tasks.”

Brain scans also revealed changes in the hippocampus, an area of the brain critical for memory.

The study’s authors write:

“The hippocampus is a critical brain region for memory formation and plays important roles in the consolidation of information from short-term memory to long-term memory and spatial navigation.

[…]

Our results suggest that 12-month DHA supplementation significantly increased hippocampus volume.

Notably, we observed a 6.13% volume increase in the left hippocampus, a 1.89% increase in the right hippocampus, and a 0.29% increase in total hippocampus.

Best supplement combination?

The use of omega-3 to prevent dementia has provided some mixed results.

B vitamins also seem to be important in warding off cognitive decline.

A recent study found that B vitamins combined with omega-3 can help slow mental decline in older people with memory problems.

The study’s first author, Dr Abderrahim Oulhaj explained the results:

‘We found that for people with low levels of Omega-3, the vitamin supplements had little to no effect.

But for those with high baseline Omega-3 levels, the B vitamins were very effective in preventing cognitive decline compared to the placebo.

Other studies, though, have been less positive about the benefits of omega-3 for cognitive decline.

It is likely that the combination of nutrients — including both B vitamins and omega-3 will turn out to be the crucial factor.

→ Related:

• Creatine: A Dietary Supplement That Boosts Your IQ
• The Supplements That Boost IQ And Memory

The study was published in the Journal of Alzheimer’s Disease (Zhang et al., 2016).

Silent strokes are early symptoms of damage to the blood vessels in the brain.

Becoming absentminded can be a clear sign of a silent stroke, research finds.

Silent strokes are early symptoms of damage to the blood vessels in the brain.

They are known as ‘silent’ as they do not cause lasting changes that are sometimes linked to strokes, such as problems speaking or moving.

However, older adults who notice they often become sidetracked or lose their train of thought could have had a silent stroke.

The study included 54 adults aged 55 to 80 who were at risk of a stroke.

Risk factors for a stroke include high blood pressure, cholesterol, diabetes and sleep apnea.

Mr Ayan Dey, the study’s first author, said:

“Our results indicate that in many cases of people who were at a higher risk of silent stroke and had one, they saw a notable difference in their ability to stay focused, even before symptoms became detectable through a neuropsychological test.

If a person feels this may be the case, concerns should be brought to a doctor, especially if the person has a health condition or lifestyle that puts them at a higher risk of stroke or heart disease.”

Although these strokes are called silent, they damage the brain’s white matter, which facilitates communication between regions.

This causes cognitive and memory issues.

Dr Brian Levine, study co-author, said:

“There are no effective treatments for Alzheimer’s disease, but brain vascular changes can be prevented or reduced through smoking cessation, exercise, diet and stress management, as well as keeping one’s blood pressure, diabetes and cholesterol under control.

With the right diagnosis, these interventions and lifestyle changes give older adults who are at risk for cognitive decline some options for maintaining brain health.”

Some people are able to continue functioning well even after experiencing brain damage.

Mr Dey said:

“The question that remains is whether overcoming these changes in the brain is a natural ability some people have or if this is something that can be built up over time.

If it’s something that can be developed, is it something we can train?”

The study was published in the journal Neurobiology of Aging (Dey et al., 2019).

Fisetin has been extensively studied for its potential to improve brain health and cognitive function.

A natural compound found in strawberries can reduce the mental effects of ageing.

The antioxidant fisetin, when given to mice, was found to reduce their mental decline with age and inflammation in their body.

Fisetin is also found in many other plants, such as apples, onions, cucumbers and persimmons.

Dr Pamela Maher, who led the research said:

“Companies have put fisetin into various health products but there hasn’t been enough serious testing of the compound.

Based on our ongoing work, we think fisetin might be helpful as a preventative for many age-associated neurodegenerative diseases, not just Alzheimer’s, and we’d like to encourage more rigorous study of it.”

Previous studies in the same lab have found that fisetin can reduce age-related memory loss.

The study was carried out on mice that had been genetically modified to be susceptible to Alzheimer’s disease.

Dr Maher said:

“Mice are not people, of course.

But there are enough similarities that we think fisetin warrants a closer look, not only for potentially treating sporadic AD but also for reducing some of the cognitive effects associated with aging, generally.”

The mice were given food with fisetin in it for 7 months and compared to a control group.

Dr Maher said:

“At 10 months, the differences between these two groups were striking.”

Those given the fisetin had hardly suffered any age-related deficits.

In general, fisetin has been extensively studied for its potential to improve brain health and cognitive function.

Like this one, some studies have shown that fisetin may have neuroprotective effects, helping to protect the brain from damage and reducing the risk of age-related cognitive decline.

It may also improve memory and cognitive performance in aging individuals.

Fruits that boost brain health

Some fruits have been shown to have potential benefits for brain health.

These include:

1. Berries in general: rich in antioxidants that can help protect the brain from damage caused by free radicals.
2. Avocados: contain healthy fats that can improve blood flow to the brain and support overall brain function.
3. Citrus fruits: rich in Vitamin C, which may reduce inflammation in the brain and protect against cognitive decline.
4. Apples: contain compounds that may protect brain cells and improve memory function.
5. Tomatoes: contain the antioxidant lycopene, which has been shown to improve brain function and cognitive performance.

A balanced diet, including a variety of fruits is key to maintaining good brain health.

The study was published in the Journals of Gerontology Series A (Currais et al., 2017).

7 psychology studies from the members-only section of PsyBlog that explain how research has found dementia risk can be reduced.

Dementia is a broad term including a range of related diseases, the most common of which is Alzheimer’s.

People with dementia tend to have problems with thinking, reasoning and making decisions.

Dementia tends to affect older people but is not a normal part of aging.

So, below are 7 psychology studies from the members-only section of PsyBlog that explain how research has found dementia risk can be reduced.

(If you are not already, find out how to become a PsyBlog member here.)

1. 3 Simple Lifestyle Changes To Reduce Dementia Risk
2. The Habit That Could Reduce Alzheimer’s Risk By 25%
3. The Best Way To Reduce Dementia Risk
4. One Tasty Fruit That Reduces Alzheimer’s Risk
5. How Sedentary Behaviours Affect Dementia Risk
6. This Positive Belief May Protect Against Alzheimer’s Disease
7. The Activity That Reverses Mild Cognitive Impairment

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Dementia breaks down the brain’s ability to perform complex tasks, like this one.

Being unable to understand sarcasm is an early warning sign of dementia, research finds.

Deterioration in key parts of the brain in neuro-degenerative diseases causes people to have problems spotting insincere communication.

Detecting lies and sarcasm is a relatively complex cognitive task.

It requires being able to simulate the other person’s mind and inferring what they must mean.

Those with dementia also find it hard to spot lies.

Dr Katherine Rankin, who led the study, said:

“These patients cannot detect lies.

This fact can help them be diagnosed earlier.”

Scientists are always looking for ways of spotting dementia earlier, as this is the key to better treatment.

The study involved 175 people, some of whom had neurodegenerative diseases.

They were shown videos of people talking, who were sometimes sarcastic or told lies.

People with frontotemporal dementia found it particularly difficult to spot the lies and sarcasm.

This could provide a useful early warning sign.

Dr Rankin said:

“If somebody has strange behavior and they stop understanding things like sarcasm and lies, they should see a specialist who can make sure this is not the start of one of these diseases.”

Other early warning symptoms of dementia include a change in sense of humour:

“Changes in sense of humour could be an early sign of dementia, a new study finds.

A shift to preferring slapstick humour — like Mr Bean — over satirical or absurdist comedy, such as Monty Python, could be an early sign of Alzheimer’s.

Friends and relatives of those with dementia reported seeing changes around nine years before the more typical memory problems.”

Another even more surprising sign of dementia is being unable to smell peanut butter.

The study was published in the journal Cortex (Shany-Ur et al., 2012).

The drug protected nerve cell functioning, reduced inflammation and nerve cell loss.

A diabetes drug that includes three growth factors has reversed Alzheimer’s-related memory loss in mice.

This is not the first drug originally aimed at diabetes that may eventually help Alzheimer’s.

Type-2 diabetes is a risk factor for Alzheimer’s, and has been implicated in the disease’s progression.

Professor Christian Holscher, who led the study, said the drug…

“…holds clear promise of being developed into a new treatment for chronic neurodegenerative disorders such as Alzheimer’s disease.”

Dr Doug Brown, Director of Research and Development at Alzheimer’s Society, said:

“With no new treatments in nearly 15 years, we need to find new ways of tackling Alzheimer’s.

It’s imperative that we explore whether drugs developed to treat other conditions can benefit people with Alzheimer’s and other forms of dementia.

This approach to research could make it much quicker to get promising new drugs to the people who need them.

Although the benefits of these ‘triple agonist’ drugs have so far only been found in mice, other studies with existing diabetes drugs such as liraglutide have shown real promise for people with Alzheimer’s, so further development of this work is crucial.”

The drug was tested on mice genetically engineered to suffer from Alzheimer’s.

The study found that the drug reduced amyloid plaques — protein build-ups linked to Alzheimer’s.

It also protected nerve cell functioning, reduced inflammation and nerve cell loss.

This is the first evidence that a so-called ‘triple receptor’ drug can be effective.

It uses three different growth factors — GLP-1, GIP and Glucagon — that target impaired signalling in Alzheimer’s patients.

Professor Holscher said:

“These very promising outcomes demonstrate the efficacy of these novel multiple receptor drugs that originally were developed to treat type 2 diabetes but have shown consistent neuro-protective effects in several studies.

Clinical studies with an older version of this drug type already showed very promising results in people with Alzheimer’s disease or with mood disorders.

Here we show that a novel triple receptor drug shows promise as a potential treatment for Alzheimer’s but further dose-response tests and direct comparisons with other drugs have to be conducted in order to evaluate if this new drug is superior to previous ones.”

The study was published in the journal Brain Research (Tai et al., 2018).

Around one-third of dementia cases are avoidable.

Half of all adults in the UK cannot identify a single risk factor for dementia, a survey reveals.

Many people surveyed thought dementia was inevitable, however it is possible to reduce the risk.

Around one-third of dementia cases are thought to be avoidable.

Six of the risk factors are:

• high blood pressure,
• heavy drinking,
• genetics,
• smoking,
• depression,
• and diabetes.

One of the main protective factors against dementia is exercise (lack of exercise being the seventh risk factor).

Sue Strachan, 63, who was diagnosed with vascular dementia in 2014, said:

“I wasn’t very fit when I was diagnosed with dementia and my GP advised me to take up exercise to try to manage my condition.

I do wish I’d started earlier, because good heart health can have such a positive impact on the brain.

I can see that society’s view of dementia is improving, but I still experience misunderstanding about the condition – not least that there’s nothing that can be done to help.

We must make sure people are informed about dementia, so they’re more likely to engage with advances in research that could make such a positive difference to people’s lives in future.”

Alzheimer’s Research UK surveyed 2,361 people about the risk factors for dementia.

Just over half knew someone with dementia.

Hilary Evans, chief executive of Alzheimer’s Research UK, said:

“It is a sad truth that more people are affected by dementia than ever before and half of us now know someone with the condition.

Dementia is the UK’s biggest killer but only half of people recognise it even causes death, and almost half of UK adults are unable to name one of seven known risk factors for dementia including smoking, high blood pressure and heavy drinking.”

→ Read on: 12 ways to prevent 40% of dementia cases.

The survey was conducted by Alzheimer’s Research UK.