Category: Memory

Case questions traditional ideas about how memory works.

The case of a man who can only remember the last 90-minutes of his life has baffled psychologists.

The symptoms are like those depicted in the film Memento.

They came on after the 38-year-old had a routine dental procedure, including a local anaesthetic and root-canal treatment.

Subsequently, he lost the ability to create new memories.

Now, the man — who is referred to as ‘WO’ to protect his identity — wakes up every day thinking he has a dental appointment.

However, there’s no evidence that the dental procedure caused the condition.

This is what has puzzled the scientists.

Normally, such serious memory problems are accompanied by brain damage, typically in a structure called the hippocampus.

But, in WO’s brain there are no structural abnormalities.

Apart from the memory problems, WO seems the same as before, physically and psychologically.

He is capable of learning (although he forgets everyting within a day), his personality is the same and his intellect is intact.

Dr Gerald Burgess, who describes the patient in the journal Neurocase, said:

“One of our reasons for writing up this individual’s case was that we had never seen anything like this before in our assessment clinics, and we do not know what to make of it, but felt an honest reporting of the facts as we assessed them was warranted, that perhaps there will be other cases, or people who know more than we do about what might have caused the patient’s amnesia.

Our experience was that none of our colleagues in neurology, psychiatry, and clinical neuropsychology could explain this case, or had seen anything like it themselves before.”

The case could question established ideas about how memory works.

Dr Burgess said:

“…we should perhaps not be so stuck in thinking that profound amnesia only occurs in the context of visible damage to the brain’s hippocampal and/or diencephalon structures — those structures appear just to be needed for the initial holding or retention of information before engrams then proceed slowly through several other neuro-electrical and neuro-chemical events, before finally permanent memories are stored, and that something can occur at some later point in this process to vanquish the memory trace permanently.”

The study is published in the journal Neurocase (Burgess & Chadalavada, 2015).

Image credit: jodene

Memory does not decay, forgetting helps you learn, and more…

“If we remembered everything we should on most occasions be as ill off as if we remembered nothing.” ~William James

It’s often said that a person is the sum of their memories. Your memory and recall is what makes you who you are.

Despite this, memory and recall is generally poorly understood, which is why many people say they have ‘bad memories’….

CONTINUE READING —->>

Image credit: kozumel

The brains of 2,028 people with schizophrenia were compared to healthy controls.

People with schizophrenia have smaller volumes in critical areas of the brain, a new study finds.

The research supports the idea that schizophrenia can be linked to disturbed brain development.

The areas affected include the hippocampus, which is involved in the formation of long-term memories.

Along with a smaller hippocampus, the amygdala and thalamus were also smaller in those with schizophrenia.

The amygdala processes emotion, while the thalamus regulates consciousness, sleep and alertness, amongst other functions.

The research compared brain scans of 2,028 people with schizophrenia with 2,540 healthy controls.

Professor Jessica Turner, who co-led the study, explained where their data came from:

“This is the largest structural brain meta-analysis to date in schizophrenia, and specifically, it is not a meta-analysis pulled only from the literature.

Investigators dug into their desk drawers, including unpublished data to participate in these analyses.

Everyone performed the same analyses using the same statistical models, and we combined the results.

We then identified brain regions that differentiated patients from controls and ranked them according to their effect sizes.”

Professor Turner continued:

“There’s the increased possibility, not just because of the massive datasets, but also because of the collaborative brain power being applied here from around the world, that we will find something real and reliable that will change how we think about these disorders and what we can do about them.”

The study was published in the journal Molecular Psychiatry (van Erp et al., 2015).

Network brain image from Shutterstock

Plus this short-term diet reduces belly fat and slows aging.

A diet which mimics fasting could boost neural regeneration, leading to improved memory and learning, a new study finds.

In addition, just five days dieting per month is enough to steadily reduce belly fat and slow aging, the study found.

The diet involves eating around 50% less calories over five days in a month.

Professor Valter Longo, an expert on longevity who led the study, said:

“Strict fasting is hard for people to stick to, and it can also be dangerous, so we developed a complex diet that triggers the same effects in the body.

I’ve personally tried both, and the fasting mimicking diet is a lot easier and also a lot safer.”

The effects of the diet were tested on both mice and humans.

Cognitive rejuvenation was seen in the mice.

The pilot study on 19 people found the diet reduced biomarkers of aging, diabetes, cardiovascular risk and cancer.

Professor Longo said:

“It’s about reprogramming the body so it enters a slower aging mode, but also rejuvenating it through stem cell-based regeneration.

It’s not a typical diet because it isn’t something you need to stay on.”

For the remaining 25 days of the month people ate their normal diet.

Professor Longo believes that most normal people would only need to do the diet every three to six months to see the benefits.

Those who are obese could do it more often, if their doctors considered it safe.

Professor Longo said:

“Not everyone is healthy enough to fast for five days, and the health consequences can be severe for a few who do it improperly.

Water-only fasting should only be done in a specialized clinic.

Also, certain types of very low calorie diets, and particularly those with high protein content, can increase the incidence of gallstones in women at risk.

In contrast, the fasting mimicking diet tested in the trial can be done anywhere under the supervision of a physician and carefully following the guidelines established in the clinical trials.”

The study was published in the journal Cell Metabolism (Brandhorst et al., 2015).

Image credit: Liz Jones

Which of the images above is the Apple logo?

If you selected “B” then you did better than 84 out of 85 UCLA students who were asked the same question.

All 84 got it wrong.

And this was in a group in which 52 were exclusively Apple users, while fully 75 owned Apple products.

They were presumably seeing the logo multiple times each day: on their computer, iPads and iPhones.

And yet they couldn’t pick it out of this line-up.

This was despite being very confident beforehand that they would be able to draw it from memory.

Dr Alan Castel, one of the study’s authors, said:

“There was a striking discrepancy between participants’ confidence prior to drawing the logo and how well they performed on the task.

People’s memory, even for extremely common objects, is much poorer than they believe it to be.”

The reason for this discrepancy is that our minds focus on information that’s really important to us, although we don’t realise it.

The details of a corporate logo are not that important in our daily lives.

Our memories tend to store the ‘gist’ of information rather than the specifics.

You’d easily be able to tell the Apple logo from the Windows logo, but drawing both accurately would be a challenge.

The study’s authors write of the classic example that…

“…people often have difficulty recognizing the correct locations of features on a penny.

Although pennies are common objects, people may not have a functional reason for encoding the specific features of currency.

However, people often fail to recall the location of previously seen fire extinguishers, despite the fact that fire extinguishers are in high-visibility locations and are associated with high-risk situations.

Explicit memory is also poor for items that people interact with daily, such as the keypads of calculators, telephones, computer keyboards, the layout of frequently-used elevator buttons, and aspects of road signs.”

So if you feel your memory is poor, then take heart from this study — it just means the stuff you can’t remember isn’t that important to you.

The study is published in The Quarterly Journal of Experimental Psychology (Blake et al., 2015).

Image credit: Adam Blake, Meenely Nazarian, Alan Castel/UCLA Psychology

New research reveals how to ‘turn on’ your memory, how to flush out useless memories and more…

Rounding up some of the latest research on memory, here are five recent studies revealing new insights into how memory works.

(Click the links for longer descriptions of the studies.)

‘Turn on’ your memory

Paying attention isn’t enough to commit things to memory.

Memory has to be ‘turned on’ in order to remember even the simplest details, a recent study f0und.

When not expecting to be tested, people can forget information just one second after paying attention to it.

But, when they expect to be tested, people’s recall is doubled or even tripled.

Dr Brad Wyble, one of the study’s authors, said:

“It is commonly believed that you will remember specific details about the things you’re attending to, but our experiments show that this is not necessarily true.

We found that in some cases, people have trouble remembering even very simple pieces of information when they do not expect to have to remember them.”

Classical music enhances memory genes

Listening to classical music enhances the activity of genes involved in learning and memory.

At the same time it reduces the activity of genes involved in neurodegeneration.

The conclusion comes from the first study to show how music affects the transcription of genes across the whole genome.

Transcription is the first step in how genes are expressed — in other words, how our genetic code is turned into proteins.

Improve memory five-fold

A power nap of under an hour can improve memory performance by five times.

New information normally disappears from memory quite rapidly as people naturally forget.

But, after a 45-60 minute nap, participants in one study had forgotten little.

In comparison those who had remained awake had forgotten a lot.

Flush out useless memories

Clicking ‘save’ on a digital file makes your memory worse for that information, but improves it for what you learn subsequently, a new study has found.

The trick probably works because taking a photo or saving a file flushes the information out of consciousness, freeing up cognitive resources for the next task.

Dr. Benjamin Storm, who led the study, said:

“We tend to think of forgetting as happening when memory fails, but research suggests that forgetting plays an essential role in supporting the adaptive functioning of memory and cognition.”

Recall leads to forgetting

Recalling one memory actually leads to the forgetting of other competing memories, research has confirmed.

It is one of the single most surprising facts about memory, now isolated by neuroscience research.

Although many scientists believed the brain must work this way, this is the first time it has been demonstrated.

Dr Maria Wimber, a cognitive neuroscientist and the study’s first author, said:

“Though there has been an emerging belief within the academic field that the brain has this inhibitory mechanism, I think a lot of people are surprised to hear that recalling memories has this darker side of making us forget others by actually suppressing them.”

Image credit: A Health Blog