Category: Memory

How we breathe affects brain activity, memory and the emotions.

Breathing in through the nose boosts memory because inhaling stimulates the brain.

Scientists have shown for the first time how the rhythm of breathing affects electrical activity in the brain.

People were more likely to remember objects they had encountered while breathing in than breathing out, the study results showed.

While breathing in, people were also quicker to identify a fearful face.

Mouth breathing did not have the same effect — it had to be inhaling through the nose.

Dr Christina Zelano, the lead author, said:

“One of the major findings in this study is that there is a dramatic difference in brain activity in the amygdala and hippocampus during inhalation compared with exhalation.

When you breathe in, we discovered you are stimulating neurons in the olfactory cortex, amygdala and hippocampus, all across the limbic system.”

The scientists first came across this curious phenomenon when studying seven patients with epilepsy.

Recordings of their brain activity showed it changed with breathing.

For the study, 60 people were shown faces on a computer screen and later objects they had to remember.

There was evidence of the same curious changes of brain activity with breathing.

Rapid breathing may give us a cognitive advantage in some situations, said Dr Zelano:

“If you are in a panic state, your breathing rhythm becomes faster.

As a result you’ll spend proportionally more time inhaling than when in a calm state.

Thus, our body’s innate response to fear with faster breathing could have a positive impact on brain function and result in faster response times to dangerous stimuli in the environment.”

Dr Zelano said it also provided insight into how practices like meditation affect the brain:

“When you inhale, you are in a sense synchronizing brain oscillations across the limbic network.”

The study was published in the Journal of Neuroscience (Zelano et al., 2016).

The common drink that may protect the brain against memory loss.

Drinking orange juice regularly is linked to a 47 percent lower risk of memory problems with age, research suggests.

Berry fruits, orange and red vegetables and leafy greens may also help protect against memory loss.

The results come from a study that followed 27,842 men for 20 years.

Every four years they were asked about the foods they ate and were given tests of their memory and thinking skills.

They were also asked questions including:

• “Do you have more trouble than usual remembering a short list of items, such as a shopping list?”
• “Do you have more trouble than usual following a group conversation or a plot in a TV program due to your memory?”

Those that had six servings of fruit and vegetables a day were 34% less likely to experience poor thinking skills later on.

Eating more fruit and vegetables in midlife was linked to better cognitive health later on — even if the men stopped eating fruit and vegetables.

Dr Changzheng Yuan, study co-author, said:

“One of the most important factors in this study is that we were able to research and track such a large group of men over a 20-year period of time, allowing for very telling results.

Our studies provide further evidence dietary choices can be important to maintain your brain health.”

The study only showed an association, it does not prove causation.

The study was published in the journal Neurology (Yuan et al., 2018).

Psychologists uncover a simple method to make parting with unwanted possessions easier.

People are more likely to give away unneeded goods if they first take a picture of them.

For people who find their houses filling up with stuff they no longer use, the psychological trick could help them de-clutter.

Dr Rebecca Reczek, study co-author, said:

“What people really don’t want to give up is the memories associated with the item.

We found that people are more willing to give up these possessions if we offer them a way to keep the memory and the identity associated with that memory.”

Preserve the memory

The study involved 797 students who saw an advert for a donation drive.

Half the students saw an ad that said:  “Don’t Pack up Your Sentimental Clutter…Just Keep a Photo of It, Then Donate.”

The other half saw an ad that said: “Don’t Pack Up Your Sentimental Clutter, Just Collect the Items, Then Donate.”

Students that ‘preserved’ the memory of what they were donating with a photo were more likely to give things away.

Dr Karen Winterich, study co-author, said:

“The project got started when I realized I was keeping an old pair of basketball shorts just because they reminded me of beating a major rival basketball team in junior high.

I didn’t want the shorts — I wanted the memory of winning that game and that’s what I thought of when I saw the shorts.

A picture can easily mark that memory for me and I can donate it so someone else can use it, which is even better.”

The study suggests an easier way to let go of old stuff, said Dr Reczek:

“It is not terribly surprising that we can keep the same memories alive just by taking a photo of these possessions, but it is not a natural behavior.

It is something we have to train ourselves to do.”

Memories of the item are also linked to our identities, further studies found.

Dr Reczek said:

“These memories connected to possessions are a carrier for identity.

It is this reluctance to give up a piece of our identity that is driving our reluctance to donate.”

The trick may not work for items that are sold or that have strong sentimental value.

The study was published in the Journal of Marketing (Winterich et al., 2018).

The number of chunks of information we can hold in mind at any one time.

People can hold around 4 things in mind at any one time.

While there may be no limit to long-term memory, short-term memory is not so capacious.

Four chunks of information — whether words, numbers or whatever — is the human limit.

Even then, short-term memory only lasts around 15 to 30 seconds.

Professor Gordon Parker, author of the paper, said:

“So to remember a seven numeral phone number, say 6458937, we need to break it into four chunks: 64. 58. 93. 7.

Basically four is the limit to our perception.

That’s a big difference for a paper that is one of the most highly referenced psychology articles ever – nearly a 100 percent discrepancy.”

The ‘magic number’

Professor Parker is referring to a famous research paper by American psychologist George Miller.

Miller argued that the ‘magic number’ for the chunks we can hold in memory is 7 (plus or minus two).

Decades of memory research, though, has revealed that this figure is a little optimistic.

Some people can only hold around three things in mind at once, others can manage five, but for most of us four is the ‘magic number’.

Unless, of course, you are a baby, then you can only hold one thing in mind at a time.

Professor Parker said:

“There may be no limit in storage capacity per se but only a limit to the duration in which items can remain active in short-term memory.

Regardless, the consensus now is that humans can best store only four chunks in short-term memory tasks.”

Miller’s genius was really in marketing his idea, despite the scientific facts not backing it up, Professor Parker argues.

Seven is a number that has a sort of magical hold on us, which is perhaps why Miller chose it.

So, Professor Parker mounts his tongue-in-cheek defence of four:

“There are more four-lettered swear words than any other number.

Numerous sports have teams operating as foursomes.

Even golfers play in fours (and plus fours), and the last word a golfer is most likely to hear is four than seven.

Cricketers hit fours to applause and major sporting events (e.g. Olympic Games, World Cup Rugby, World Cup soccer) are held every four years.

The most popular board games (e.g. Scrabble, Monopoly) are designed for four players – as for card games – while card packs have four suits.

Swingers most commonly swing in foursomes, luck requires a four-leaved clover, and the Americans wisely waited until the fourth of July to declare their independence.

This article was prepared on A4.

So, for every deep and profound, even metaphysical, argument for seven, I suspect we can find four times as many for four.”

The study was published in the journal Acta Psychiatrica Scandinavica (Parker, 2012).