How the mafioso in your brain keeps your business running

There is a guy who gets things done

He lives in the in-between spaces.

He’s the guy who takes care of business. The guy who takes out the trash. The ‘removal man’. The ‘eraser’. The mafia call this guy ‘the cleaner’.

Your brain has one too.

He’s the brain’s hired gun, removing the corpses, executing the soon to be corpses, and disposing of the bodies.

He takes care of the grey matters.

You should meet him.

The grey matter

It’s common to hear the brain referred to as ‘the grey matter’. And, in truth, some of it is.

Most of it isn’t.

The grey matter, formally known as the Substantia grisea, is packed with the cell bodies of neurons, and has a very light grey tinge, given by the density of the cell bodies.

In a cross-section of your brain you can see the grey matter easily, as it’s in contrast to the rest of your brain, seen as white. Simply, white matter refers to the stuff in your brain that isn’t grey. It’s whiter due to having fewer cell bodies, and is made up primarily of myelin, and glia, or glial cells.

Only 15% of your brain’s volume is grey matter. The remainder is the white matter, the myelin and glia.

The white matter

Myelin is the fatty stuff that wraps itself around the long, rope-like axon of neurons, giving them a chain of sausages appearance and helping facilitate the nerve impulse from the cell body down the axon to the end of the cell. In a brain cross-section, you see it particularly in fibres that join one part of the brain to another, either within the cerebrum (the cortex or outer layer of the brain and a few structures underneath it) or between the cerebrum and structures deeper in the brain.

Glial cells, often considered the brain’s glue (glia comes from the Greek meaning glue), are remarkable, and more than simple glue. Myelin is actually an outgrowth of glial cells, and glia also helps maintain structure in the brain by surrounding neurons and holding them in place. The fattiness of glial cells helps insulate neurons, and they provide oxygen and nutrients to brain cells.

But as R. Davidson Fields pointed out in The Other Brain, (no affiliate link) his unfolding of our growing awareness of glia’s abilities, scientists discovered that glia even have their own communication network, in parallel to the more familiar communication system. It’s not electrically governed but manages still to spread information broadly across the brain.

And it’s one of these glial cells, the microglia, that takes care of your messy business, of the clean up.

The cleaner in your brain

Comprising about 15% of glial cells, microglia are roving removal men, efficiently eliminating dead cells, mercilessly executing dying cells and disposing of their bodies. They hunt for the waste byproducts of mental activity such as plaques (deposits of beta-amyloid protein seen in Alzheimer’s disease) and look for infection to deal with. They’re related to white blood cells which perform the same functions outside the brain.

They always seemed to be cannibalistic, living on dead and dying neurons. But more recent work shows they have a broader diet…

A glial diet

At birth, brains have limited white matter, but begin a journey of progressive myelination. Additionally, in the young brain, innumerable new connections are made. Neurons send out fibres from their body, to join with partner neurons nearby, or in different parts of the brain. These connections and pathways are critical for the massive cognitive power the brain harnesses. You’ll remember that the connecting point between two neurons isn’t really a touchpoint, but a microscopic gap-the synapse-where all kinds of mental magic happens.

It’s the synapse across which neurotransmitters flood when released by one cell, to join with receptors on the adjacent cell, activating it or preventing it from activating. It’s in the synapse that psychiatric medications typically work, affecting the quantity and effect of the neurotransmitters there.  The more you use a synapse, the stronger the connection between those two cells becomes. It’s an extraordinary place.

But in the developing brain, amidst the morass of new connections, many turn out to be poor quality or wrongly connected, and must be expertly and ruthlessly pruned off. But it’s not a random pruning. This selective cutting literally shapes the developing brain, and is crucial to its connectivity. Removing unnecessary synapses allows room for growth and, like any gardener knows, prune some off and the remaining ones grow stronger.

They must be cleaned up, and microglia feed on the synapses also.

Cornelius Gross, and colleagues, from the European Molecular Biology Laboratory (EMBL) in Monterotondo, Italy, showed how this happened back in 2011, by demonstrating that proteins found inside the synapse, are found also in the bellies of microglia, evidence of their diet.

Sometimes, they don’t eat enough

Overabundance of connections impairs the ability of connections to grow in strength, as there are simply too many connections to feed, and activity is frenetic and weak rather than deliberate and strong.

Building on his earlier work, Gross and collaborators at the Istituto Italiano di Tecnologia (IIT), in Rovereto, and La Sapienza University in Rome, published new research this week in Nature Neuroscience. They note that for many people with autism (and other neurodevelopmental disorders), different parts of the brain communicate poorly, a result of the microglia failing to prune hard enough because there simply weren’t enough of them.

“We show that a deficit in microglia during development can have widespread and long-lasting effects on brain wiring and behavior,” says Cornelius Gross, “It leads to weak brain connectivity, decreased social behavior, and increased repetitive behavior, all hallmarks of autism.”

Microglia have a significant impact on the developing brain, and directly affect its connectivity and performance. But beyond even their impact in the early years of life, the sheer amount of white matter we have affects us throughout our lifespan.

It changes as we age

We know that in the early years of life the brain proliferates cells and prunes, and then undergoes a similar, slightly smaller-scale process around late childhood/early puberty. White matter, also, changes as we age, and age-related differences in white matter are linked to specific cognitive abilities in childhood and adulthood. And in a study published this week in Biological Psychiatry, Dr. Bart Peters and colleagues of the Zucker Hillside Hospital, investigated age and neurocognitive performance, in relation to nine white matter tracts, from childhood to late adulthood.

“Our study identified key brain circuits that develop during adolescence and young adulthood that are associated with the growth of learning, memory and planning abilities. These findings suggest that young people may not have full capacity of these functions until these connections have completed their normal trajectory of maturation beyond adolescence,” commented Peters.

“Our brain is changing throughout our lives. These changes underlie the capacities that emerge and are refined through adulthood,” explained Dr. John Krystal, Editor of Biological Psychiatry. “There are clues that the steps that we take to preserve our medical health and stimulate our minds also serve to further refine and maintain these connections. For good reasons, attending to brain health is increasingly a focus of healthy aging.”

So here’s the take home bit

Microglia, a subset of your glia, perform the dirty work of removing dead and dying cells. But more than just housekeeping, they are actively responsible for pruning synapses, directly shaping the brain and how it communicates with itself.

Additionally, overall white matter is critical for long-term cognitive performance, and it continues to develop and refine as we age.

Impressive words to drop into the morning coffee chat

Substantia grisea, microglia, glial cells

What do you think?

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How your macho ego is slowly destroying your brain.

Macho Man - Randy Savage

Macho Man – Randy Savage

Maybe you’ve done it too

The report isn’t finished, the deadline is tomorrow, and it just has to be done.

You have no choice.

So you’ve loaded up on Red Bull, No-Doz, whatever legal upper you can get, and got busy.

You worked through the night.

You got it done.

You’re a legend.

And maybe it’s killing you.

The all-nighter

When it’s occasional, we can usually feel fine within a few days. The day immediately after the all-nighter itself, is usually manageable.

The next day is a killer.

The day after slightly less so, but still pretty ugly.

Going without sleep for only a single night substantially disrupts our daily clock, our circadian rhythms, and the brain takes considerable time – days that is – to get things back in order. Regularity is crucial for sleep, and so the brain seeks to restore it, including how much time it spends in each of the stages of sleep.

Broken sleep, such as when you have a new baby, is different again, in that we seem constantly tired, sleep is disrupted every night, and it can take months to get on top of our own sleep.

But make no mistake… if you deprive the brain of sleep, incurring a sleep debt as you go, your brain will, one way or another, make you pay. It wants to restore the balance it had, and the routine it was used to. Now that you’ve gone and messed it up, the brain wants it back.

There is always a cost, and sleep debt comes with interest.

Debt and interest

Research from the Divisions of Sleep Medicine at Brigham and Women’s Hospital, and Harvard Medical School, both of Boston, showed that prolonged sleep restriction, with concurrent disruption of the brain’s circadian rhythms, altered metabolism to the point that we increase the risk of obesity and diabetes.

Moreover, one night’s sleep loss makes the brain hungrier, affects the ability to choose proper foods, and increases the calories and grams of food we purchase the next day.

Then a recent study from Uppsala University, Sweden, identified an increase in morning bloodstream concentrations of two molecules, namely NSE and S-100B, after a night without sleep. The trick is, these molecules are typically found in the brain, and higher concentrations in the blood are indicative of conditions of brain damage, suggesting that lack of sleep, even for only one night, might contribute to loss of brain tissue, and contribute to neurodegenerative disorders.

In New York, researchers from the University of Rochester and New York University used two-photon imaging to show that sleep allowed a 60% increase in the space between brain cells, vastly increasing the flow and reach of cerebrospinal fluid, into the nooks and crannies of your brain that it can’t reach during waking hours.

The benefit of this increase in space is that waste products such as beta-amyloid proteins, which are the waste byproduct of the brain’s daily activity, are cleared much faster. Sleep deprivation interferes with this process and this potentially neurotoxic waste remains lurking in the brain. Beta-amyloid plaques are a feature of Alzheimer’s disease.

Meanwhile, Chris Phoenix and Aubrey D.N.J. de Grey argue that aging is, in short, the accumulation of damage. By this they mean the “accumulation of the intrinsic molecular and cellular side-effects of metabolism”, just as beta-amyloid is a byproduct of the brain’s activity.

We know also that severe sleep deprivation kicks the immune system into action, showing the same kind of response seen during exposure to stress. 

These effects are extra to the already well-known effects of sleep loss on concentration, attention, cognitive performance, physical performance, mood, memory and so on.

So what does that mean?

Is is too much to say that sleep deprivation causes brain problems?


Can we say that sleep deprivation causes brain disease, such as Alzheimer’s?

Maybe, maybe not.

But they’re clearly strongly correlated, and although a bi-directional relationship exists, the evidence is looking more and more like sleep deprivation can be a weighty contributor to the development of dysfunction like this.

Why then, do we persist with the all-nighter, the overdone hours, and the appearance that sleep, as author Alan Derickson writes, is for sissies.

Sleep is for sissies

In a new book, Alan Derickson (2014, University of Pennsylvania Press) makes the point that in modern American culture (which we’re extending to similar cultures) it’s a price we, and particularly men, are encouraged to pay. Stamina equals manliness.

For women, (although the book is primarily about men) with the added expectation that they look after the lion’s share of home chores, it’s not necessarily that they’re encouraged to deprive themselves of sleep, but by having to work the two jobs of employment and home, and then with the masculine expectations of the workplace to boot, they face an even steeper hill to climb.

Dangerously Sleepy explores the fraught relations between overwork, sleep deprivation, and public health. Health and labor historian Alan Derickson charts the cultural and political forces behind the overvaluation—and masculinization—of wakefulness in the United States.”

Naturally, there are standout examples of the potentially tragic consequences of sleeplessness, and Derickson references the events of Three Mile Island, and the grounding of the Exxon Valdez, along with industries notable for their ‘sleep is for sissies’ mentality and the prevailing dogma that minimizes the need for rest. 

Given what we know about both the short, and long-term consequences of sleeplessness on the brain, are we setting ourselves up for later costs? And what message are we sending those new to the workforce?

So here’s the take home bit

Is your macho ego destroying your brain.

I think so.

Love to hear your thoughts.

Impressive words to drop into the morning coffee chat

Beta-amyloid, neurotoxic

What do you think?

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Can a pill make you a singing star by rewiring your brain?

Justin Timberlake


I am a terrible singer.

I can’t sing a very good range, and I can’t sing notes within that range very well.

When I try to hold a note for longer than a nanosecond, it ends up being not one note but many notes as I wobble erratically around the intended pitch, and it’s so bad it makes small children cry.

The perfect pitch fairy never waved her wand at me. For that matter, neither did the regal nose, chiselled chin or piercing look fairies but that’s another story.

Researchers would say that perfect pitch is partly inherited, but mostly the result of early and frequent exposure and training in music (effort), during the critical learning period (timing), before the age of six. Two things to note here.

You’ll already know that the more effort we put into an endeavor, the more connections we can grow, and the more brain space is devoted to that endeavor. People with perfect, or absolute, pitch, show an increase in the size of their planum temporale, with both right and left structures enlarged, and the left planum temporale being larger than the right.

Critical periods are fixed windows of time in which we learn different skills easily and quickly, the effects of which long outlast the window. They usually occur early in life, and rely on the brain’s plasticity, or malleability, which enables swift and smooth reorganization to accommodate new information and experience.

Question is…

can you re-open them, for absolute pitch, and then other things?

Language for example, is learned most easily as a child, before about 8 years old. Learning a second language is the same. Move to another country with kids and they can pick up the language, and dialects, in no time at all with no effort, and no trace of an accent. They sound like natives.

Parents, on the other hand, carry the accent of their mother tongue into the newly acquired language, which they had to try much harder to learn. It’s not that they can’t learn it, it just seems so much more difficult. Wouldn’t it be great to absorb Spanish like a seven year old? (By the way, there’s a quick phonetics explanation and test after the guff at the bottom.)

Visual and auditory systems have critical periods, and the brain as a whole has periods of cell proliferation followed by cell pruning, so windows of development are a familiar concept.

Opening and closing them at will however, is a different story.

Recent proof of concept work by Takao Hensch, Professor of Molecular and Cellular Biology, and Professor of Neurology, at Harvard University’s Department of Molecular and Cellular Biology, sought to discover whether opening these periods back up again might be possible. The implications of such a find are intriguing.

Neuroplasticity allows us to learn easily. A malleable brain can more quickly and easily adapt and incorporate new information. If we’re able to augment our abilities through manipulating neuroplasticity, after the period of plasticity has closed, then what might be possible? If one window opens, can we open others? Can we learn languages? Can we acquire other skills effortlessly? Can we learn more easily?

Critical periods

From birth, when the brain is overloaded with synapses (the connections between brain cells), the brain grows swiftly through to about age five, then slows to about age 20, carefully pruning as it goes, and discarding unnecessary connections. Critical periods occur during these early years, and are shaped by growth and pruning.

Chemically, BDNF (brain-derived neurotrophic factor), a nerve growth chemical, operates like fertilizer on tomatoes, generating growth. Particularly, this protein activates the nucleus basalis, a small brain structure that sharpens attention, and stays switched on throughout the critical period. BDNF also consolidates connections between cells, which is crucial for memory. Once the critical period ends, the nucleus basalis is switched off.

Hensch notes that “behaviorally induced plasticity in the healthy brain, typically after the end of the relevant critical period, can lead to improvement beyond normal or average performance levels”.

He would add that this usually involves specifically targeted training, beyond what we would consider regular use. The training needs to be repetitive, intense, and relevant.

So what if there were another way?

Hensch also knew that growing older, along with experiential events, conspire to close the windows of critical periods. One of these changes involves an enzyme known as HDAC (histone-deacetylase) which halts critical period learning, much like putting on a hand brake stops a car. Research in mice had already shown that inhibiting HDAC could remove the brake in the visual and auditory systems. Could it work in humans? Could Hensch teach absolute pitch beyond the critical period by chemically releasing the brain’s learning hand brake?

Could I be a singing star after all?


In a randomized, double-blind, placebo-controlled study, 24 males received either placebo, or VPA treatment. None of the men had musical training as children. Variations of VPA, or valproate, are commonly used for reducing seizures in epilepsy, stabilizing mood in bipolar disorder, and in other psychiatric conditions. It’s also a HDAC inhibitor.

Following a period of online ear training, Hensch tested the men on how well they could discriminate between tones. If the experimental group outperformed the placebo group, then there would be evidence that the window had opened.

And it had.

Confirming their hypothesis, performance varied by experimental group. In Hensch’s words “Normal male volunteers performed significantly better on a test of AP (absolute pitch) after 2 weeks of VPA treatment than after 2 weeks of placebo”.

As he should be, Hensch is cautious. This doesn’t open the floodgates for massive-scale pharmo-educational snake oil, biotech commercialization, super soldiers, overnight geniuses, or anything.


So here’s the take home bit

Specific skills like this don’t necessarily translate to improvements in other areas so, for example, general intelligence doesn’t necessarily improve. Transfer to related areas is possible, but not automatic.

Hensch notes his small sample size, and that the work needs to be replicated before we get carried away. Others note the potential side effects of chemicals. Hensch sees the crudeness of this approach but opines that, if replicated, their “study will provide a behavioral paradigm for the assessment of the potential of psychiatric drugs to induce plasticity”.

The subtext is that psychiatric conditions can be overcome by harnessing the power of plasticity, however that plasticity is unlocked. Already, cognitive behavioral therapy re-sculpts the brain and chemicals can open critical windows.

Can newer work in optics switch on the nucleus basalis. It’s the BDNF gene that maps BDNF. Could we turn this on through transcranial electrical stimulation thereby turning on the nucleus basalis.

We don’t know. But we can tell that the ground is moving.

As for absolute pitch and my latent signing career, I’m still waiting for the fairy.

Impressive words to drop into the morning coffee chat

Brain-derived neurotrophic factor (BDNF)

What do you think?

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Learning languages

By way of illustrating critical periods and learning languages, English has 44 sounds. Other languages have more, or fewer.

Say ‘tip’ aloud. Phonetically, the opening ‘t’ sound in the word tip, is represented as /t/. Structurally, your mouth and tongue make the same movements for /t/ as for ‘d’ in dip, represented as /d/. Remember this symbol represents the sound, not the letter. The difference is that to make /d/, you have to add voice. Same goes for /p/ and /b/.

Here’s a test. Put your fingers on your voicebox and say ‘pump’ followed by ‘bump’. Feel your voicebox vibrate for the /b/ sound, but not the /p/ sound? Other pairs are /f/ and /v/, /k/ and /g/ and so on. We also have diphthongs, which are sound combinations; the ‘dg’ sound in ‘judge’, the ‘ch’ of church’ and so forth. And by the way, ‘phonetics’ in phonetics, is /fəˈnɛtɪks/.

We learn our native sounds easily, and once they’re learned, we lose the ability to learn new ones as easily, as the ability to make them disappears with the closing of the critical window. Most of us don’t use the click consonants of the Bantu, or the ‘ll’ sound found in Welsh, or the back of the mouth sounds found in Arabic, and would have to learn to master them, mashing our mouth around the necessary tongue, lip and teeth positions, let alone adding voice.

A young child, within the window, with nucleus basalis switched on, would pick them up quickly, regardless of the language.

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Does size matter? Pink brains blue brains.

Image thanks to MARIE CLAIRE MagazineYawn

So women have smaller brains than men. It’s hardly surprising really.

They also have smaller feet, hands, noses, ears, hearts, lower red blood cell count, lower base metabolic rate, less muscle mass and height.

Among other things.

The highbrow term for these kinds of differences is Sexual Dimorphism.

Neil Sears wrote about male/female differences a couple of months ago, identifying that, on average, a woman’s brain is 8% smaller than a man’s.

Curiously, women are about 8% shorter than men too, on average. Knowing about sexual dimorphism as you now do, you’d have to say that it makes perfect sense for a woman’s brain to be smaller than a man’s.

Women are smaller than men. Period.

Big is good. No?

But we do know that size IS important, insofar as the amount of brain cells and, especially, the number of connections between cells, matters. It matters a lot. Quantity and connectedness are critical.

And although we might struggle to say that a woman’s hands and feet are less effective than a man’s because they are smaller, is it a different story when we come to the brain? Does a smaller brain make a difference?

Let’s start from the very beginning…

Differentiation between boys and girls begins at conception. It’s the Dad who determines whether children are girls or boys, because the Dad (sex chromosomes XY) can donate either an X or a Y sex chromosome. Mom (sex chromosomes XX) always donates an X sex chromosome. The baby is XY (boy) or XX (girl), depending on which sex chromosome it inherits from dad to go with the X from mom.

Anatomically though, you can’t tell if a fetus is a boy or a girl until after about 12 weeks from conception. Although external genitals begin to develop from 6 weeks in utero, both boys and girls look the same. The same tissue later develops into the differentiated sex organs of boys and girls.

It’s why the organs differentiate that is of interest to us.

Hormones 1

From about 12 to 18 weeks, a boy baby will release a massive hormone surge. These hormones get straight to work defeminizing him (making sure he doesn’t develop into a girl) and masculinizing him (making sure he does develop into a boy). Both processes are required.

These are staggering, widespread changes, and create irreversible effects, with massive impact on the brain, and give rise to the traits, behaviors and characteristics we recognise as male.

Girl babies don’t get this hormone surge, so being a girl is, if you like, nature’s default setting. Stuff has to happen to a fetus to make it a boy. If a boy baby doesn’t get this hormone surge, he will be a boy by chromosome (an X from mom and a Y from dad) but anatomically female, or indeterminate, because he wasn’t defeminized and wasn’t masculinized.

Hormones 2

About three months after birth, boys get another massive hormone dose.

Don’t underestimate how much these surges flood this immature brain and cause change. Moreover, because there are extra, complicated steps to make sure a fetus becomes a boy, there is much more opportunity for things to go wrong. For example, more boys develop schizophrenia, learning difficulties, language difficulties, autism spectrum disorders and antisocial personality disorder.

Subsequent gender differences in behaviour seem obvious to everyone. Boys and girls play differently, compete differently, communicate differently and so on.

No surprises, boys are different from girls.

And girls end up with a smaller brain.

So what?

Can this explain some of our common psychological understanding? Is a smaller or larger brain responsible for differences we experience?

And while we’re here, can women multitask better than men? Are men better at parallel parking or reversing cars than women? What about women’s intuition?

Neil Sears said that the woman’s brain was smaller, yes, but also more efficient, especially in the region of the hippocampus, a critical memory structure. Whereas in men a larger structure indicated higher intelligence, this wasn’t true of women. Rather, greater connectivity suggested that women can achieve the same as men, with fewer brain cells and less effort.

Ask any woman and she’ll tell you that she already knew that…

Moreover, recent work out of Penn Medicine, published in the Proceedings of the National Academy of Sciences, found males had greater neural connectivity from front to back, and also within one hemisphere, whereas in women the wiring was stronger between hemispheres.

Ragini Verma, PhD, an associate professor in the department of Radiology at the Perelman School of Medicine at the University of Pennsylvania, notes “These maps show us a stark difference—and complementarity—in the architecture of the human brain that helps provide a potential neural basis as to why men excel at certain tasks, and women at others”.

For men, the connections link the perception and coordination areas, suggested they excel at coordinated action. Women show stronger communication between the analytic and the intuitive, by which they mean the left and the right hemispheres respectively, demonstrating strengths in emotional processing and inferring the actions of others in social situations.

The authors observed only a few gender differences in the connectivity in children younger than 13 years, but the differences were more pronounced in adolescents aged 14 to 17 years and young adults older than 17.

Hormones 3

These age-related observations fit with the third major hormone surge, also called puberty. Naturally, girls get this too, and both bodies and brains change again. During this time, brains undergo a rapid growth in brain cells. They proliferate in number, before being pruned back to then remain at a relatively stable number throughout life.

The Penn researchers would further argue that these connectivity differences can also suggest that men are probably better at single focused task as cycling or navigating directions which require greater spatial awareness. The hippocampus, a key structure investigated in Sears’ article, is also partly responsible for navigation.

Women, with their different connectivity, better memory and social skills, are better suited to group solutions and multitasking, the researchers say.

So perhaps we can say, with some assurance from Penn, that men are generally spatially stronger, and women better socially. Neil Sears also puts men as better spatially, and women better at inductive reasoning and tracking changes. This may well explain the sex battles over parallel parking (win for the boys) and multitasking (win for the girls).

As a caveat, we should note that these are generalities and these (and all) abilities lie on a continuum, with people spread along that continuum from one end to the other, including women who are spatially better than men and men who better at inductive reasoning than women, and so on.

So where are we?

So let’s agree with Neil Sears and sexual dimorphism that men have larger brains.

Let’s agree that men and women have different abilities.

Let’s agree that a brain bathed in testosterone at three critical periods is going to change the brain in substantial ways.

Then let’s agree that we’ve oversimplified and not even allowed for the complexity of genes, the fact that experiences can turn genes on and off, that diet, sleep, exercise, poverty, maternal diet, paternal diet, birth order and a million other things impact the quantity and connectivity of your brain.

And let’s agree that it isn’t simply a matter of size.

A well-connected female brain is going to be better than a poorly connected male brain, regardless of size. Albert Einstein, for example, despite his seemingly large head, had a smaller than average brain. By and large, we consider him pretty smart.

So here’s the take home bit

It’s the connectivity that is critical.

100 cells, connected only once each, is a much smaller network, with much less ability to function, re-route information, and remember, than 50 cells connected 25 times each. Men and women have brains that are connected in different ways. Assuming you eat well, get enough sleep, and exercise a bit, developing connections between brain cells by stimulating the brain is the key to efficiency, shaping intelligence, and brain longevity.

What we should be asking, is not whether one brain is better than another, but how do we make our own better.

A postscript…

While we’re talking about boys and girls, two things.

Women’s intuition is not a mysterious superpower. It is most likely the result of greater lateral connectivity and social awareness, allowing them to recognise patterns better than men. It’s not mysterious, it’s a skill.

And for the record, and though it is something we don’t seem ready to believe, men talk as much as women. Yes, fellas, you do 🙂

Impressive words to drop into the morning coffee chat


What do you think?

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2 easy ways to help your kids learn to read you’ve never thought of.

Reading hurts

Learning to read can be torturous for many children.

Among a raft of other personal or individual difficulties children may have, English is such a hard language to learn, even for native speakers.

Partly it’s because many words are borrowed from other languages, but also partly because some of it, well, just doesn’t make sense.

Try explaining to a non-English speaker how it is that it’s perfectly reasonable to chop down a tree and then chop it up.


But semantics, or meanings, are only one thing. Simple pronunciation is another.

Say this list aloud as quickly as you can.

Bar, car, far, jar, mar, par, tar, war.

Why do they all rhyme, except for ‘war’? And that’s not even allowing for ‘ear’, and then ‘oar’ which, in fact, rhymes with war.

And lest we forget, remember trying to remember which ‘ough’ sound you had to use, when there are up to 10 variations?! Maybe you’ve seen this before: A rough-coated, dough-faced, thoughtful ploughman strode through the streets of Scarborough; after falling into a slough, he coughed and hiccoughed.

Learning all of this is daunting, particularly when you consider the gymnastics the brain has to do to manage it all. Just how complex it is might surprise you.

If you don’t want to be surprised, hop down to the section If only there were things to make it easier. Number 1.

No wonder it’s hard

For example, recent research out of USC Brain and Creativity Institute shows that different components of reading are located in different parts of the brain, and each relates strongly to the amount of gray matter (the amount of individual neurons) in those parts.

Postdoctoral research associate Qinghua He looked at three facets:

  • phonological decoding ability (the ability to sound out printed words);
  • form-sound association (how well subjects could make connections between a new word and sound);
  • naming speed (how quickly subjects were able to read out loud).

MRI analysis demonstrated that

  • Phonological decoding ability was strongly connected with gray matter volume in the left superior parietal lobe (top/rear of the brain)
  • Form-sound association was strongly linked with the hippocampus (a pivotal memory structure deep inside the temporal lobe) and cerebellum (the “little brain” sitting underneath the brain at the top of your neck).
  • Naming speed lit up a variety of locations around the brain.

Former colleague and collaborator, Gui Xue, points out that reading is really a set of independent capacities, supported by discrete neural systems, which are independent of general cognitive abilities.

An implication of their work is that an MRI scan may reveal why someone struggles to read and suggest therapies for them targeted at a particular brain region.

And then we have to put it all together

But these skills, distinct though they may be, are basically mechanical, and still require integration for reading and, especially, for comprehension. Writing is a way of communicating meaning. Consequently, readers need to be able to comprehend what they read in order to draw that meaning from the text.

Integration requires that we link words together over time, keeping them in the right order, with their right meanings, in memory, so that we can then make sense of the phrase, the sentence, the paragraph, and the story. Much of this relies on your working memory, and something you’re doing right now as you read this.

Julia Mossbridge, a research associate in psychology at Northwestern University, along with co-authors Marcia Grabowecky, Ken A. Paller and Satoru Suzuki of Northwestern, have shown recently that this integration is a higher level, frontal lobe function. Moreover, there is a distinct neural pattern for people who are good comprehenders, which differs markedly from those who are weaker at comprehension, even if they can manage the mechanics of reading perfectly well.

So although nearly all kids learn to speak perfectly well, picking up rules of grammar swiftly, and learning the exceptions as they go, it’s no wonder they find reading harder. Spelling is yet harder again.

Fair enough then that parents, tasked with the primary responsibility of teaching their children to read, struggle along with them, particularly those with limited access to books or text, or for whom reading is difficult.

If only there were things to make it easier. Number 1.

So here are two simple, effective and inexpensive strategies, which carry a number of added benefits.

Work published by Dr Nina Kraus, Northwestern University, highlights that auditory working memory (a subset of the memory you’re using to read right now), such as the ability to hear, remember and execute instructions while on a task, is an important part of musical ability. What’s remarkable she notes, is how strongly musical ability is linked to verbal memory, and literacy, in childhood.

Her team discovered that weaker readers had diminished neural response in the brainstem (at the top of your spine going into the brain) to rhythmic, rather than random sounds, when compared to good readers. A good score on the acoustic test correlated highly with musical ability, especially rhythm, and reading ability. Additionally, a good auditory working memory score related to stronger reading and rhythmical musical ability.

Dr Kraus explained, “Both musical ability and literacy correlated with enhanced electrical signals within the auditory brainstem. These results add weight to the argument that music and reading are related via common neural and cognitive mechanisms and suggests a mechanism for the improvements in literacy seen with musical training.”

More specifically, when testing high school students, Kraus recognized the inherent importance of rhythm to music and language. Rhythm is essential to understanding speech, for it imparts meaning, along with differentiating certain sounds.

“Musicians have highly consistent auditory-neural responses,” notes Kraus. “It may be that musical training—with its emphasis on rhythmic skills—can exercise the auditory-system, leading to less neural jitter and stronger sound-to-meaning associations that are so essential to learning to read.”

If only there were things to make it easier. Number 2

The other tip is perhaps even simpler, and is really a slight twist on something you might already do.

It’s long been a tenet of education that readers can learn the rules of phonics when words are presented differing in only one sound

University of Iowa researchers would disagree. Their recent work, published in “Developmental Psychology” highlights that particular types of variation in words may help early readers learn better. When kids see the same phonics regularities, such as the ‘ai’, located in words with more variation, such as ‘paid’ and ‘hair’ rather than ‘paid’ and ‘maid’ , they may learn these critical early reading skills better. What might seem at first to be more difficult, facilitates better learning.

Their research showed that variety was better, regardless of the student (boys, girls, weak readers, strong readers etc).

And here’s how to do it

When you pair the variety with good delivery, you’re onto a winner. Most certainly, reading with your children is bedrock behavior; we simply must do it as a foundation for learning. And here’s the secret sauce that makes it even better

Naturally, kids love cuddling up to a parent to read, and it’s fantastic bonding time. Dr Thea Cameron-Faulkner and Dr Claire Noble from The University of Manchester, have shown that reading to kids, from simple or complex stories, is hugely beneficial, and not just for bonding and language.

The key for language, they say, isn’t in the text, but in having a complex conversation about the story. Both types of books produced more complex language than a free play situation, such as when a parent and child played with a toy kitchen.

Dr Cameron-Faulkner, adds “It’s pretty well established that sharing books with young children improves their vocabulary and literacy development, and that language skills are linked to academic attainment generally – including maths.

“Recent studies indicate that one of the key predictors in children’s mathematical skill is early language experience, and so the rich linguistic experience associated with shared book reading may have benefits above and beyond language development.

“Our research shows quite clearly that books are a valuable source of language input: the language used when sharing books contains more complex, structurally rich constructions than everyday child directed speech. And because a simpler book is just as valuable as a more complex one, this is good news for parents who may struggle with their reading.”

Researchers from the University of Washington, Temple University, and the University of Delaware show us that it’s the responsiveness of the interactions that’s crucial. When we respond to children in timely and meaningful ways, they learn.

So here’s the take home bit

Rhythm and music can be taught and encouraged from a very early age, long before reading becomes an issue. A child with a strong sense of rhythm , and good musical training, is more likely to grasp reading more easily, and become a strong reader. We’ve seen in other posts that reading is an important function for brain fitness, and the benefits of learning to play music can far outlast the playing itself.

Read to your kids, engaging them in complex conversation about the story or picture, for this is how they’ll learn language the best. Because kids’ books are often repetitive, use the opportunity to teach phonics through variety, either in the text, or in your conversation.

Note, too, that engaging with your child through music, to learn rhythm, also provides opportunity for complex conversations.

Worth a try?

Impressive words to drop into the morning coffee chat

Phonological decoding ability, form-sound association, naming speed, 

What do you think?

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New computing power discovered in the brain

We often compare the brain to a computer 

Think about the mechanics of yours for a moment.

It’s 1.3 kilograms of congealed porridge, held together by cling film, surrounded by fluid, enclosed in a spider web, wrapped in a leathery case and protected by your skull.

Although unimpressive to look at, its scale is mind-boggling.

You own approximately 100 billion brain cells. Your individual neurons are about 4 microns thick. 30,000 of them would fit on a pin head.

You have more than 125 trillion synapses, or connections between brain cells, in the cortex alone. The synapse, a tiny gap between the edges of two of your brain cells, is smaller than a thousandth of a millimetre.

You have more than 100,000 miles of blood vessels, capillaries and transport systems, through which passes nearly a litre of blood every minute.

Your brain is capable of 0.1 quadrillion computations per second which it performs almost effortlessly most of the time, and without you realizing how much work it’s actually doing.

 Is it as good?

But for all that, the biggest meanest computers outdo the brain in pure computational power, able to generate calculating grunt more than ten times what the brain can do, without getting tired. They aren’t called supercomputers for nothing, and pack a formidable processing punch that they brain can’t compete with.

At least, not in that sense.

From out of the beginning of each brain cell come spindly projections, called dendrites, looking like roots of a bush. Each dendrite increases the surface area of the brain cell and, much like roots sucking up water for the benefit of a plant, dendrites receive information from other cells and relay it to their parent.

At least that’s what we thought

Rather than being bit-part actors in the brain, dendrites themselves do more than passively pass on information. They are active players, processing information as they go and, therefore, multiplying the brain’s raw computing power.

Add to the 100 billion brain cells the additional power of hundreds of billions, even trillions of dendrites, and we can grasp at what a machine the brain really is.

“Suddenly, it’s as if the processing power of the brain is much greater than we had originally thought,” said Spencer Smith, PhD, assistant professor in the UNC School of Medicine, and one of the team whose research was published in Nature, October 27. Already, the research has asked searching questions about long-held beliefs

The dendrites have their own computational resources, and contribute to information processing in a way we had not imagined, the implications of which are fascinating. Suddenly, there is a springboard for computing power as neurons can harness the capability of their dendritic spines.

Spines and spikes

It’s in the axon, the long fibre running from the cell body, where brain cells usually generate their electrical spike. Interestingly, molecules present there to support the axonal spike, are also present in the dendrites. We knew that dendrites can use such molecules to generate their own electrical spike, but didn’t know if this was a part of normal brain activity.

Take vision for example. We ‘see’ with the visual cortex, located at the back of the brain. A key question from this new development is, Might dendritic spines, and the spikes they create, be involved in how we see?

According to Smith, absolutely yes. Senior author Professor Michael Hausser adds: “This work shows that dendrites, long thought to simply ‘funnel’ incoming signals towards the soma, instead play a key role in sorting and interpreting the enormous barrage of inputs received by the neuron. Dendrites thus act as miniature computing devices for detecting and amplifying specific types of input”.

So how do you prove it?

Proving this took some time, and no small effort. The researchers were aiming to “listen in” to a single dendrite in a mouse’s brain, trying to hear the electrical signalling of the single dendrite.

“Attaching the pipette to a dendrite is tremendously technically challenging,” Smith said. “You can’t approach the dendrite from any direction. And you can’t see the dendrite. So you have to do this blind. It’s like fishing if all you can see is the electrical trace of a fish.” And you can’t use bait. “You just go for it and see if you can hit a dendrite,” he said. “Most of the time you can’t.”

So, he built his own two-photon microscope system to do it instead.

Once the pipette was reliably attached to a dendrite, the team began to record the electrical activity from single dendrites. The mice were anesthetized, but awake, which meant they could watch visual stimuli while the researchers recorded their brain activity. And as they watched, they noticed strange new things.

The dendrites themselves were spiking.

And not randomly, but selectively, and based on the visual stimulus they were encountering. This showed beyond doubt that the dendrites themselves were processing what the mouse was seeing.

To develop visual evidence of their discovery, Smith’s team filled neurons with calcium dye, which provided an optical readout of spiking. This showed clearly that dendrites themselves spiked while other neuronal parts did not, showing that the spikes were due to localized processing in the dendrites.

His team plans to explore what this newly discovered dendritic role may play in brain circuitry and particularly in conditions like Timothy syndrome, in which the integration of dendritic signals may go awry.

So here’s the take home bit

It’s an old chestnut to say that if the brain were so simple we could understand it, we would be so simple that we couldn’t.

What is clear, is that the brain has resources, capacity and systems still yet to be understood. It remains the most complex thing we know.

We build computers to do one thing, repeatedly, very fast. They aren’t a match for what you possess.

Impressive words to drop into the morning coffee chat

Dendritic spines

What do you think?

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Playing craps with your kids’ brains.

Image courtesy of

Image courtesy of


You know how playing craps goes…

You hold the dice, you shake them three times in cupped hands, three times in that hand, three times in this hand, then you blow on them, then you do some other ritualized superstitious bunk, then you toss them against the backboard and hope like crazy they come out ok.

Kind of like raising children really, except you’re unlikely hear someone yell out “Winner winner chicken dinner!” when you’ve just performed some particularly impressive parenting maneuver.

And to be fair, it sometimes feels like parenting is as much of a crapshoot as, well, craps.

But unlike craps, when it comes to you, your kids, and their brains, you often don’t see the results of your dice throwing until much later. All the more pressure to get it right early, no?

While some things just don’t really matter, there are a couple of simple, but crucial, things we’d like you to take to heart if you’re the parent of a young brain. And if you’re now simply the custodian of your own, older brain, the concepts still apply.


We recently finished a five-post series on reading from books versus reading online. On this blog, we’re heavily in favor of reading books as a key developmental component for kids and teens, and a tool to keep us sharp through life.

While we stopped short of saying the internet will turn your brains to pond slop and that you shouldn’t use it (this is an online blog after all… irony noted) we do promote minimal screen time for kids.

Generally, for infants and toddlers up to say, age three, none is good. You read that right. They don’t need screen time.

And while screens are ubiquitous these days (how many in your house?) and we won’t escape them, we’ll do our kids’ brains a favour in the long-term by limiting screen time now.

And adults could do with less too.

In short, brains need time away from the constant demands that screens place on them.

Mental overload

You might recall we’ve talked a little about cognitive load, which is the amount of mental work we can manage, given the limited resources the brain has. It’s an important concept when we come to learning and screens.

Remember, while it’s about only two per cent of your body weight, the brain uses 20% of the oxygen you breathe, and 20% of the glucose in your bloodstream. When it’s running out of either, it doesn’t function very well. It has physical stamina and endurance limits, and capacity limits.

While long-term memory may be limitless, working memory, which is the capability you’re using right now to hold a few things in mind while you work with something, is absolutely limited. Seven things,  plus or minus two, has always been the rule, but we know it’s actually closer to three or four and, if the material is a little more complex, two.

That isn’t much

So if you want to put something new into working memory, something else will have to come out.

And giving the brain too much to filter, sort, choose from, remember, pay attention to, and so on, exceeds your cognitive load.

When you consider that the brain is a sucker for novelty, and struggles to ignore new things, a feature every television advertiser, video game designer and web designer knows and exploits, you can understand how taxing screens are on brains and how easily we fall into the trap of staring at them for extended periods.

Note: this blog ought to have more internal and external links to push it further up rankings, make it more clickable and so on. I don’t, because your brain doesn’t need it 🙂

But while they make us expend energy, it’s energy only for working memory. What happens is that you temporarily strengthen existing connections between brain cells while you’re working on that task. This is in contrast to long-term memory, which permanently strengthens connections AND grows new connections.

Give your brain a break

Erik Fransen, a researcher from Stockholm’s KTH Royal Institute of Technology, says that a brain exposed to a typical session of social media browsing can easily become hobbled by information overload. The result is that less information gets filed away in your memory.

He continues, adding that contrary to common wisdom, an idle brain is in fact doing important work – and in the age of constant information overload, it’s a good idea to go offline on a regular basis, because downtime gives opportunity for the brain to sort, file, organize, consolidate and, yes, delete information.

It’s necessary breathing space.

With working memory, as we look to pile more things into it, not only do we use up its limited storage capacity, the load we give it also reduces our capacity for information processing. The reason, unfortunately, is that some of the same resources we use for working memory, are used for information processing.

Consequently, we need to keep some of this processing capacity free to think about what we’re reading or seeing.

Think about it like this

Put it this way. You’ve been shopping for groceries and brought home a number of bags. You put your keys on one finger, then load up every spare finger with another bag. You’ve got as much load as you can carry. This is like your cognitive load, now full.

When you get to the door, you’re so busy holding onto the bags, that you can’t use your fingers to use the keys and open the door. This is the overlap between information processing capacity and working memory. You’ve exceeded your load, all your fingers used to hold bags, but at least a couple of these fingers are needed to open the door.

The only way you can open the door, is to put down some bags, reduce your load, and free up some fingers.

Same goes for your brain.

So here’s the take home bit

Managing kids’ brains doesn’t need to be a crap shoot. Limit time in front of screens now to give their brains time to process information.

Give them time to focus on non-screen things for extended periods of effort with tasks of increasing difficulty.

Music practice is one. Book reading is another – aim for 20 minutes a day.

Be conscious of time onscreen (any screen) and the load it places on brains – your’s too.

Winner winner chicken dinner!

Impressive words to drop into the morning coffee chat

Working memory, cognitive load

What do you think?

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The myth of left brain vs right brain.

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Left vs Right

The left brain.

Logical. Analytical. Mathematical. Organized. Systematic.

The right brain.

Creative. Artistic. Intuitive. Spontaneous. Emotional.

We’ve used these two descriptions to facilitate job selections, team selections, team building activities, personality profiles and testing, parenting, teaching and a host of other things.

The appeal of the left-brain/right-brain split lies in how simple it is.

Some examples

Want to be more creative? Then what you can do is present information to the left visual field which for both eyes crosses over into the right hemisphere. This will activate your creative right hemisphere and give you awesome ideas.

Side note: It’s a common misconception that information from the left eye goes to the right hemisphere, and information from the right eye goes to the left. This is true of the body’s movement, but not the eyes. The left visual field of both eyes cross to the right hemisphere. The right visual field of both eyes crosses to the left. The crossover happens at the optic chiasm, located underneath the brain where the optic nerves cross each other. 

Feeling stuck with a problem at work? Get a team of right-brainers to dream up a creative solution for you. You can select the team using an online left/right brain inventory.

Stuck face to face in an interrogation with a suspect? Ask her a hard question. If she looks to the right, she’s accessing her logical left hemisphere and, therefore, telling the truth. If she looks to the left she’s accessing her creative right hemisphere and, therefore, lying.

The only problem with this classification, apart from making us lazy, is that it’s wrong.

The left-brain/right-brain idea is a myth.

The two brains

We clearly have two, distinct halves to our brains: the left and right hemispheres. They’re separated by the longitudinal fissure, which is the groove running from front to back, right in the middle of your brain.

Longitudinal fissure

Longitudinal fissure

Because some brain functions are located largely in one hemisphere or the other, we generalized to say the left side of our brain does one thing, and the right another.

We then generalized further to say people thought in that way or the other, so we were left-brained or right-brained. Having only two ways to categorize people is great, because we then don’t have to try very hard. You’re either one or the other.

Life gets way harder when we have a number of ways of classifying things, so two is simple.


Brodmann’s areas are the most enduring categorization system for the brain, developed by Korbinian Brodmann and based on how cells were structured and organized. We still use them. But Brodmann’s areas don’t suggest personality from location like the left-brain/right-brain split.

Maybe you remember phrenology, which inferred ability, personality and character from the shape of your skull.

The idea was that located in the brain were a range of distinct faculties, each with its own location. The size of the particular location was evidence of the power of that faculty. As the shape of the brain was believed to be accurately reflected on the skull, we could determine your mental and moral characteristics by examining your skull.

Neuroimaging studies tell us a different story, thanks to work carried out by University of Utah researchers.

The new work

Lead author Jeff Anderson notes the truth that some functions are lateralized, which means they are generally specialized to one hemisphere or the other. Language, for example, is typically found in the left hemisphere. Attention is generally found in the right.

But while some functions may reside in this way, it is a step too far to infer that we think with one side more than the other, or that this is somehow a determinant of personality.

It is as easy, for example, to infer the opposite, that our personality shapes how we think, and determines which side could be more dominant.

For this study researchers used the resting brain scans for more than 1,000 people, aged between seven and 29. Each person had lain in a scanner while their resting brain activity was analysed, a process which took about five to ten minutes.

This allowed the researchers to compare activity in one region with that in another. All up, the researchers divided the brain into 7,000 regions and then analyzed which regions were more lateralized, which means the activity was occurring in one hemisphere rather than both.

What seems more the case is that rather than having a thinking preference for one side or other, or for the brain to be dominated by one side or the other, most regions in the brain have connections to the other hemisphere.

In some of these, one side may outweigh the other, but that relates only to that region and its lateral connection, and not to the whole hemisphere. They found no relationship that suggests we choose or prefer to use the left-brain over the right, or vice versa.

Most of us are whole-brain thinkers, using different areas as we need

Researcher Jared Nielsen, a graduate student in neuroscience, says “If you have a connection that is strongly left-lateralized, it relates to other strongly lateralized connection only if both sets of connections have a brain region in common”.

So here’s the take home bit

We are constantly looking for ways to classify all kinds of things, including people, as this makes life easier.

In this case, we can’t use the left-brain/right-brain idea any more.

What we can do, is focus on those functions that could use a little more work, and build our efforts around those.

Impressive words to drop into the morning coffee chat

Optic chiasm, Longitudinal fissure

What do you think?

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How to create a false memory – in someone else’s head

Imagine guerilla warfare taking place inside your brain

Some cells are, deliberately, targeted and destroyed. Others are manipulated on an individual, chemical level.

Insurgents, rebels, or hired neuro-mercenaries actively seek to implant, alter, or destroy memories inside another person’s mind.

Governments pass laws requiring all new babies to be fitted with memory modification devices allowing them lifetime access to the minds of their citizens.

The voice of Big Brother no longer booms its exhortations from the speakers on the street, but silently, in the propagandist memories in your mind.

Eye witness testimony, already on shaky ground, is deemed inadmissible in court, as every recollection is tainted by the threat of tampering.

Memory is what makes us who we are.

What if you couldn’t trust any of it… ?

Engineered memories are here.

Building memories

We know well that memory is a reconstructive process. Every time you activate a memory, the brain reconstructs it from the ground up, physically rebuilding the memory.

It’s the same when we build memories in the first place. Give a rat a maze and they can’t help but find their way through it, being the explorers that they are. This forms a pattern of brain activation unique to that memory.

While it sleeps that night, its brain will activate that circuit, over and over and over again, at breakneck speed, from start to finish, repeating it in order to consolidate the memory so that when it wakes up, it can remember how to run the maze.

This, in itself, is extraordinary. Given that different parts of memories are stored in different parts of the brain, memories must be accessed from multiple locations and then synthesized together, called binding, for you to remember.

The seeming ease with which we remember stuff belies how staggering a feat it really is.

We’ve also known we could interfere. Wake the maze-running rat while it’s replaying the circuit, and you interfere with the consolidation process, so it won’t remember how in the morning.

But what about creating memories.

MIT neuroscientists have done just that. And the thing is, the brain didn’t know the difference.

How they did it

It’s an impressive piece of science.

They did it by turning on the light. Last year, Susumu Tonegawa (Picower Professor of Biology and Neuroscience and senior author of this research article, published Science, July 25), and his research team manipulated cells in the hippocampi of mice.

The hippocampi are those structures in the brain responsible chiefly for transferring short-term memories into long-term memories.

What the engineered cells did was express the gene for a groovy little protein known as channelrhodopsin. This protein activates the neuron it’s in when it gets stimulated by light, kind of like a jumpstart.

But in a clever next step, they then modified the gene so that the channelrhodopsin protein would be made whenever the c-fos gene, which is crucial for memory formation, was activated.

By putting mice in a particular chamber and giving them a mild electric shock, the mice learned to be afraid of the chamber, as they would normally. As this memory was formed, the c-fos gene was activated and, along with it, the modified, light-sensitive channelrhodopsin proteins.

The result was a real, physical, tangible memory, tagged with proteins that were sensitive to light.

MIT neuroscientists identified the cells (highlighted in red) where memory traces are stored in the mouse hippocampus (Photo: Steve Ramirez and Xu Liu / MIT)

The MIT team identified the cells (shown as red) where memory traces are stored in the mouse hippocampus (Photo: Steve Ramirez and Xu Liu / MIT)

The day after, when the mice were placed in a new, unfamiliar chamber they behaved as they normally would, sniffing and exploring.

But when the researchers administered a pulse of light directly to the hippocampus, they stimulated the memory cells that had been tagged with channelrhodopsin, which is sensitive to light. This activated the previous day’s memory, of fear.

Accordingly, the mice froze, overcome with fear.

So now that you could do this, could you play with a little more?

Tinkering in the brain

Skip to this year.

Day 1

The mice were put in one of four, new, unique boxes, Chamber A. As before, they start to explore, unafraid. No shocks were administered, and the mice behaved as normal.

Day 2

The mice are put in a new box, Chamber B, different from the first.

After a bit, the mice are given a gentle electric shock to the foot. It’s not harmful, but it is unpleasant. Immediately, of course, c-fos genes are activated and the mice start to make memories of this box and the fear, associating the two together.

As you know now, these memories will be light-sensitive, as channerhodopsin was also produced.

And here’s the cool bit

At precisely the same time as the shock, the mice were given a pulse of light to the light-sensitive neurons that had encoded the memory from the previous day, in Chamber A.

Day 3

The mice are placed back in Chamber A. Remember, nothing had happened here two days ago. They had sniffed and explored and encoded a memory of this chamber as normal.

And you can probably guess what happened now.

The mice froze.

Although they had never experienced fear in this box, they felt fear associated with Chamber A because, when the shock was given in chamber B on Day 2, they were experiencing the memory of being in chamber A.


A new, false memory, indistinguishable from others, and which subsequently affected what the mouse did.


And slightly spooky at the same time.

What if?


It’s a million miles from anything happening to people, but it does raise interesting possibilities about what you could do.

If you could…

Would you willingly alter some memories so they were more positive?

Would you willingly delete some memories entirely?

Would you willingly implant entirely false memories if it helped you feel better?

Is cosmetic memory alteration a good thing?

Would you condone altering the memories of others if they have suffered trauma?

Would you accept that, if we could do these things, they would also be used for ill?

So here’s the take home bit

Clearly we’re a long way from anything untoward and there’s nothing to fear. The possibilities, while tantalizing, are extraordinarily complex.

For now, we can be impressed by the really cool science they performed and, at the same time, aware of our own idiosyncrasies and weaknesses.

And tomorrow, will you trust what you remember?

Impressive words to drop into the morning coffee chat


What do you think?

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Paper vs Pixels. Does it matter how we read? Conclusions.

Image courtesy of

Image courtesy of

Is it too dramatic?

You think I’m overdoing it to write that we’re outsourcing our minds to SEO?

Probably not.

Interesting things are happening to your brain, the more time you spend reading online as opposed to reading from books.

Reading books, or from paper, focuses the brain on an effortful task, deepening its grasp of what you’re reading, plugging into memories you already have, and helping it forge new connections. (You can read like this online too, it’s just harder and, in any event, much of the web isn’t structured that way.)

It promotes deep thinking, and in doing so, helps build brains. You cannot hope to grow a muscle without exercising it. Likewise, you cannot hope to grow your brain without exercising it.

Side note:Repeated activation of connections strengthens those same connections. It also promotes the growth of myelin, a fatty insulator that wraps around brain cells and facilitates transmission of communication within cells.

As we practise a skill for example, we can see improvements in our performance; smoother, better execution etc. Myelin is at work to help. The more myelin you have, the better.

Frequently used circuits, those you’ve exercised or practised the most, are also the most physically durable. They withstand more disease and damage. By extension, the more frequently you make the brain focused on a task, the more myelin, the tougher your brain.

When you exercise working memory only, such as when we’re on the web, the brain responds by partially and momentarily strengthening existing connections between neurons. It does this at the synapse, which is the juncture between neurons, for the time that you’re working with that piece of information.

This is what happens when we skim, which is fast becoming the dominant style of reading. However, because working memory has only a limited capacity, and its contents are regularly changing, and there is a steady stream of information and distractions, creating a high cognitive load, the brain isn’t firing the same connections over and over, but a range of them.

What we’re doing is offering the brain so much choice, that its resources become overwhelmed, and it doesn’t learn.

Repetition, not endless variety, is key to learning. It’s the timely repetition that hones a skill, growing myelin and, creating magic.

When you engage the brain in deeper concentration, deeper thinking, which leads to long-term memories, such as when you read books, or when you think deeply and effortfully on a task, new things happen.

Awesome things.

Magical things

Neurons split open, rupturing to give birth to new extensions of themselves which slither and slip their way towards neighboring brain cells.

It is a marvel.

Momentary strengthening of the synapse, the place where two neurons meet, is characteristic of working memory. But when neurons stretch, when they split and form new synapses, alongside repeated strengthening of existing synapses, this is the development of Brand New Connections.

This is the formation of long-term memory. This is how we learn and remember, and it’s how the brain builds itself into a physically stronger entity.

By creating tissue and networks that are physically more robust, we give the brain depth, more substance, and the capacity, should it need it, to move functions around in the face of trauma or disease, to withstand more damage.

A brain built largely on working memory is a house built on sand. It will become intellectually weak and cognitively flabby. It will be more susceptible to weakening, less capable of deep thinking, and complex reasoning, and more easily overwhelmed.

A working memory brain relies on speed and flexibility, but it’s error prone, automatic, limited in capacity, relying on familiar and recent things rather than careful, sustained thought. We must have working memory, and we must nurture it. But, alone, it isn’t enough.

Repetition strengthens synapses and builds new connections. We need myelin. We need brains capable of complex reasoning and deep thought. We need to read books and turn off the distractions. Distractions breed distractibility, and increase cognitive load, which undermines learning.

Read a book.

Paper defeats pixels.

To conclude

The web is changing your brain, like it or not. It’s becoming weaker, less able to concentrate for prolonged periods, and less able to hold what it saw. Your memory might not be what it was.

No matter you think…

Sure, you can go to your history and find the web page again. Everything is instantly available again with the click of your mouse on a pre-populated search box in an engine designed to make sure you never have to think much and clouds to ensure you never have to remember…

So here’s the take home bit

Read to your children. Read yourself. A lot.

Turn off the tv.

Turn off the monitor.

Have mandatory electronic free time.

Play strategy games, language games and maths games with your kids.

For that matter, play games with your friends.

When your kids are younger, read aloud. It’s better. When they’re older, still read aloud.

Seriously. Go and do it now.

Welcome back.

Buy books and teach them to love them.

Use books as the foundation of education.

A brain built on reading, and a brain built by education, is a tougher, more resilient, more capable brain with deep cognitive reserve.

Yes, an education is still the best defence against dementia. 

Curiously, even in a brain ravaged by dementia, reading stays intact.

A resilient, physically strong brain, will last the distance.

The brain the web builds, will not.

Impressive words to drop into the morning coffee chat

Working memory, distractibility

What do you think?

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