The Body Shape Linked To Memory Problems

The study adds further evidence for the cognitive disadvantages of this body type.

The study adds further evidence for the cognitive disadvantages of this body type.

Overweight people have worse memories for times, places and specific emotions they have experienced, a new study finds.

The higher people’s BMI, researchers found, the worse their episodic memory.

Episodic memory is the collection of memories that occurred at a particular moment in time.

It is often contrasted with semantic memory, which is our general knowledge about the world.

The study adds further evidence for the cognitive disadvantages of being overweight.

Dr Lucy Cheke, who led the study, said:

“Understanding what drives our consumption and how we instinctively regulate our eating behaviour is becoming more and more important given the rise of obesity in society.

We know that to some extent hunger and satiety are driven by the balance of hormones in our bodies and brains, but psychological factors also play an important role — we tend to eat more when distracted by television or working, and perhaps to ‘comfort eat’ when we are sad, for example.

Increasingly, we’re beginning to see that memory — especially episodic memory, the kind where you mentally relive a past event — is also important.

How vividly we remember a recent meal, for example today’s lunch, can make a difference to how hungry we feel and how much we are likely to reach out for that tasty chocolate bar later on.”

The study tested 50 people with a range of BMIs from 18 to 51.

The normal range for BMI is 18-25, 25-30 is considered overweight and over 30 is obese.

Researchers found that the higher people’s BMI, the worse they performed on a memory task.

Dr Cheke said:

“We’re not saying that overweight people are necessarily more forgetful, but if these results are generalizable to memory in everyday life, then it could be that overweight people are less able to vividly relive details of past events — such as their past meals.

Research on the role of memory in eating suggests that this might impair their ability to use memory to help regulate consumption.

In other words, it is possible that becoming overweight may make it harder to keep track of what and how much you have eaten, potentially making you more likely to overeat.

The possibility that there may be episodic memory deficits in overweight individuals is of concern, especially given the growing evidence that episodic memory may have a considerable influence on feeding behaviour and appetite regulation.”

Dr Jon Simons, who co-authored the study, said:

By recognising and addressing these psychological factors head-on, not only can we come to understand obesity better, but we may enable the creation of interventions that can make a real difference to health and wellbeing.”

The study was published in The Quarterly Journal of Experimental Psychology (Cheke et al., 2016).

Brain image from Shutterstock

Think Faster, Remember More By Regularly Eating A Food That’s “Bad” For You

Tasty food linked to better performance on multiple cognitive tasks.

Tasty food linked to better performance on multiple cognitive tasks.

People who eat chocolate at least once a week perform better on multiple cognitive tasks, new research finds.

The study — covering 30 years — is one of the first to link regular chocolate consumption over the long-term with higher performance on multiple cognitive functions.

Chocolate could also help protect against age-related memory decline.

Dr Georgie Crichton, the study’s first authors, said:

“Chocolate and cocoa flavanols have been associated with improvements in a range of health complaints dating from ancient times, and have established cardiovascular benefits, but less is known about the effects of chocolate on neurocognition and behavior.”

Over 1,000 people included in the study had been tracked over 30 years.

A whole series of health and cognitive variables were measured.

The researchers found that regular chocolate eaters performed better on tests of working memory, reasoning and attention.

Dr Crichton explained:

“We examined whether habitual chocolate intake was associated with cognitive function (brain function – memory, concentration, reasoning, information processing), in nearly 1,000 individuals in the MSLS and found that those who ate chocolate at least once per week (or more), performed better on multiple cognitive tasks, compared to those who ate chocolate less than once per week.

With the exception of working memory, these relations were not attenuated with statistical control for cardiovascular, lifestyle and dietary factors.

This means that irrespective of factors including age, sex, education, cholesterol, glucose, blood pressure, total energy and alcohol intake, the relationship between chocolate intake and cognition remained significant.

Previous research has mostly examined the acute effects of increasing chocolate consumption on cognition, (ie performance) immediately after consuming a chocolate bar/cocoa drink.

Our research has looked at habitual intakes.”

Naturally, chocolate should be consumed as part of a healthy diet, Dr Crichton said:

“Of course chocolate intake should be considered within an overall healthy eating pattern, with consideration given to total energy intake and an individual’s energy needs.”

The study was published in the journal Appetite (Crichton et al., 2016).

Finger licking image from Shutterstock

What Your Brain Does Automatically So Some Memories Are Recalled Preferentially And Without Effort

We can only recall a very small proportion of the memories we make each day.

We can only recall a very small proportion of the memories we make each day.

New research finds that rewarding memories are recalled preferentially because the brain replays them automatically when we are at rest.

The brain prioritises rewards as they are important cues about future behaviour.

Professor Charan Ranganath, one of the study’s authors, said:

“Rewards help you remember things, because you want future rewards.

The brain prioritizes memories that are going to be useful for future decisions.”

In the study people looked at various pictures of objects on different backgrounds.

Some were associated with a higher reward for later recall.

When given a surprise memory test afterwards, unsurprisingly people were better at remembering the objects with higher levels of reward.

Dr Matthias Gruber, one of the study’s co-authors, said:

“Also, when an object was associated with high reward, people remembered better the particular background scene that was on the screen during scanning.”

The interesting finding came from a series of brain scans conducted just after people had looked at the objects, while resting.

These suggested that people were replaying the high-reward memories to help mentally fix them in place.

Their brains were doing this automatically, without volition, since they didn’t know a test was coming.

The people who replayed the memories the most did the best on the surprise test.

Professor Ranganath said:

“It speaks to a memory process that is normally hidden from us.

Are you remembering what you really need to know?

It could depend on what your brain does while you are at rest.”

The study was published in the journal Neuron (Gruber et al., 2016).

Brain image from Shutterstock

Memory And Attention Work Best At Certain Times Of The Year, Study Finds

New research suggests people’s cognitive abilities are affected by the seasons.

New research suggests people’s cognitive abilities are affected by the seasons.

Brain scans show that people’s short-term memory is generally best in fall (autumn) and worst in spring.

In mid-December, though, people’s attention skills are at their lowest ebb.

Attention doesn’t come up to full strength until June.

Dr Gilles Vandewalle, one of the study’s authors, said that the causes are likely down to multiple factors, but:

“…we may be tuned to lower brain activity in winter, and that could cause changes in brain activity.

But in modern society we are similarly active throughout the year.”

It could also be that people who experience seasonally affected disorder may be particularly vulnerable to changes in cognition over the year.

Brain Scans Reveal Why Up To One in Six People Get SAD in Winter

The new research had 28 men and women visit the lab at different times of the year to take various tests.

Both brain scans and behavioural tests were used.

Only the brain scans showed the differences, not the behavioural tests.

The study was published in the journal PNAS (Meyer et al., 2016).

Image credit: Noukka Signe

Learning and Memory Skills Can Recover From The Diet That Damages Them

Certain diets can damage learning and memory, but the brain can recover, a new study finds.

Certain diets can damage learning and memory, but the brain can recover, a new study finds.

High-fat diets have long been linked to all kinds of psychological problems, including depression, anxiety and learning and memory deficits.

Now, research on mice has found that memory and learning problems disappear over time, even while maintaining the high-fat diet.

In the study, some of the mice were fed a high-fat diet.

Compared with another group fed a normal diet, after three months they showed severe problems with spatial memory.

But, after 12 months, their brains seemed to have adjusted to the high-fat diet.

High-Fat Diet May Disturb a Range of Thoughts And Feelings

Ms Erica Underwood, one of the study’s author, said:

“Other factors behind the impairment must be recovering in the long term.

That’s the beautiful thing about the brain.

It can often recover or find alternate routes to allow normal function in spite of impairment.”

While the mice’s brains coped with the diet, their bodies fared less well.

The high-fat diet caused obesity and the males developed the symptoms of type-2 diabetes.

Professor Lucien Thompson, who co-authored the study, said:

“We saw that the males’ brains, as well as bodies, became insulin-insensitive.

They were producing more insulin because of the fatty diet, but not enough to cover blood glucose surges after an oral dose of glucose.

And while insulin normally stimulates hippocampal neurons, high-fat diet males stopped responding to insulin.”

Ms Underwood concluded:

“For the first time in human history we have large numbers of toddlers who are severely overweight.

It’s unprecedented.

With this new type of physiology we’re seeing, we don’t really know what’s going to happen to these children 20 or 50 years from now.”

The study was published in the journal Neural Plasticity (Underwood & Thompson, 2015).

I am busy image from Shutterstock

Hot Chocolate Could Help Boost Memory And Thinking Skills

60 people were given tests of memory and thinking skills after drinking this for 30 days.

60 people were given tests of memory and thinking skills after drinking this for 30 days.

Two cups of hot chocolate a day could help keep the brain healthy, a recent study finds.

The research involved 60 people whose average age was 73.

They were given tests of memory and thinking skills and the blood flow in their brains was measured.

Dr Farzaneh A. Sorond, the study’s first author, said:

“We’re learning more about blood flow in the brain and its effect on thinking skills.

As different areas of the brain need more energy to complete their tasks, they also need greater blood flow.

This relationship, called neurovascular coupling, may play an important role in diseases such as Alzheimer’s.”

Half the people in the study were given hot cocoa rich in an antioxidant called flavanol.

The other half received flavanol-poor cocoa.

Both groups continued to have hot cocoa every day for two a month.

The results showed that people who had impaired blood flow in the brain improved after drinking the flavanol-rich cocoa.

People with impaired blood flow also improved on tests of memory and thinking skills.

There was no improvement for people with normal blood flow.

Dr Paul B. Rosenberg, who wrote an editorial accompanying the study, said:

“More work is needed to prove a link between cocoa, blood flow problems and cognitive decline.

But this is an important first step that could guide future studies.”

The study was published in the journal Neurology (Sorond et al., 2013).

Brain image from Shutterstock

How The Brain Can Play Out Memories And Future Events In Fast Forward

In a few seconds our brains can play out events that would take hours or days at real time.

In a few seconds our brains can play out events that would take hours or days at real time.

The imagination has an amazing ability to compress time.

In a few seconds our brains can play out events that would take hours or days at real time.

It’s an ability we take for granted and one we need to help plan for the future.

The key to how we are able to do this is a type of brain wave which is separate to the one we use for remembering real-time experiences.

Brain cells use a series of different electrical frequencies to communicate with each other.

It’s like the way radio waves are used to communicate over long distances.

One of these frequencies, however, allows the brain to play back memories or plan future events in fast forward.

Dr Laura Colgin, one of the study’s authors, explained:

“The reason we’re excited about it is that we think this mechanism can help explain how you can imagine a sequence of events you’re about to do in a time-compressed manner.

You can plan out those events and think about the sequences of actions you’ll do.

And all of that happens on a faster time scale when you’re imagining it than when you actually go and do those things.”

It’s known that fast gamma rhythms are used to encode memories happening right now, in real time.

The researchers discovered that slow gamma rhythms are used to retrieve memories and plan for the future in fast forward.

Naturally, the extra speed causes the memories and plans to lose resolution.

It’s the same as when you compress a file on the computer and it loses some information along the way.

The findings could also have implications for mental illness, Dr Colgin thinks:

“Maybe they are transmitting their own imagined thoughts on the wrong frequency, the one usually reserved for things that are really happening.

That could have terrible consequences.”

The study was published in the journal Neuron (Zheng et al., 2016).

Brain image from Shutterstock

Eating More Vegetables Linked To 40% Better Memory

Study of 3,718 older people found that, cognitively, some people’s brains were 5 years younger.

Study of 3,718 older people found that, cognitively, some people’s brains were 5 years younger.

Eating vegetables — but not fruit — helps preserve memory, research finds.

The study of 3,718 people over 65 living in Chicago asked how often people ate particular foods and administered cognitive tests.

Professor Martha Clare Morris, who led the study, explained the results:

“Compared to people who consumed less than one serving of vegetables a day, people who ate at least 2.8 servings of vegetables a day saw their rate of cognitive change slow by roughly 40 percent.

This decrease is equivalent to about 5 years of younger age.”

Green leafy vegetables showed the strongest association with a better memory.

Older people in the study got the greatest benefit from eating more vegetables.

More than two servings of vegetables per day was linked to the slowest rates of cognitive decline in older people.

Professor Morris was surprised to find there was no link between fruit consumption and a preserved memory:

“This was unanticipated and raises several questions.

It may be due to vegetables containing high amounts of vitamin E, which helps lowers the risk of cognitive decline.

Vegetables, but not fruits, are also typically consumed with added fats such as salad dressings, and fats increase the absorption of vitamin E.

Further study is required to understand why fruit is not associated with cognitive change.”

The study was published in the journal Neurology (Morris et al., 2006).

Vegetable brain image from Shutterstock

Late-Night Snacking Is A Widespread Habit That May Damage Memory

Learning and memory could be damaged by this common habit.

Learning and memory could be damaged by this common habit.

Habitual late-night snacking could damage a type of memory and learning, a new study suggests.

Eating meals at odd hours has already been linked to metabolic problems.

This, though, is some of the first evidence of potential psychological effects.

Dr Dawn Loh, the study’s first author, said:

“We have provided the first evidence that taking regular meals at the wrong time of day has far-reaching effects for learning and memory.

Since many people find themselves working or playing during times when they’d normally be asleep, it is important to know that this could dull some of the functions of the brain.”

The study, carried out on mice, tested their ability to recognise novel objects.

Those fed when they usually slept showed worse memory performance.

The late-night-snacking-mice also had problems filing the objects away in long-term memory.

Professor Christopher Colwell, one of the study’s author, said:

“Modern schedules can lead us to eat around the clock so it is important to understand how the timing of food can impact cogitation.

For the first time, we have shown that simply adjusting the time when food is made available alters the molecular clock in the hippocampus and can alter the cognitive performance of mice.”

The mice that snacked at night also had worse sleep.

Their sleep was more fragmented and they require more naps during the day.

Researchers will need to carry out tests on human subjects to see if the effect is the same.

However, we already know from other studies that shift-workers under-perform on cognitive tests.

We also know that eating less at night may help to reduce the mental problems caused by lack of sleep.

The study was published in the journal eLife (Loh et al., 2015).

Brain image from Shutterstock

The Totally Unexpected Key To Learning

One key to learning is the exact opposite of what you’d expect.

One key to learning is the exact opposite of what you’d expect.

Forgetting is a normal and necessary part of learning, a new study finds.

The instability of memory is the key to how we transfer skills and experiences to new situations, researchers have found.

Professor Edwin Robertson, from the Centre for Cognitive Neuroimaging, said:

“Our work shows that an unstable memory is a key component of the mechanism for learning transfer.

An unstable memory prevents learning from being rigidly linked to one task; instead, it allows learning to be applied flexibly.

In this study we tested the link between a memory being unstable and the transfer of learning to a different type of memory task.

We measured how learning in one task transferred to and thus improved learning in a subsequent task.

There was transfer from a motor skill to a word list task and, vice versa, from a word list to a motor skill task.

What was transferred was a high-level relationship between elements, rather than knowledge of the individual elements themselves.”

For the research, people were given the two tests 12 hours apart.

The results showed that learning between the two different tasks was only transferred when memory was unstable.

Professor Robertson said:

“Stabilised memories consistently prevented transfer to the subsequent memory task.

This suggests that the transfer of learning across diverse tasks is due to a ‘high-level representation’ that can only be formed when a memory is unstable.

Our work has identified an important function of memory instability.

An unstable memory provides a window of opportunity for communication between memories, leading to the construction of a high-level or abstract memory representation, which allows the transfer of knowledge between memory tasks.

An unstable memory is in a privileged state: only when unstable can a memory communicate with and transfer knowledge to affect the acquisition of a subsequent memory.”

The study was published in the journal Current Biology (Mosha & Robertson, 2015).