Five Brain Myths Busted

Friday, April 25th, 2008

Head
Creative Commons License photo credit: o2ma


Myth #1

Alcohol kills brain cells.

It does a number on your limbic system and disrupts communication between message-carrying dendrites in your cerebellum - but it doesn’t kill them. The greater the alcohol intake obviously, the greater the amount of disruption. Over time, chronic alcohol ingestion (it takes a lot of alcohol - Zane Lamprey and Steve McKenna-style lots) depletes thiamine levels in the body and brain causing Wernicke-Korsakoff disease. W-K patients develop a profound amnesia, a characteristic eye-movement disorder and persistent confusion - that’s when you know (or don’t) you’ve gone too far!

Myth #2

Brain cells (neurons) are fixed from birth and never regenerate.

This is a hang-over (pun intended) from the 19th century when Spanish histologist (Nobel Prize winning histologist), Santiago Ramon y Cajal, pontificated freely on the structure of the brain. We now know however, that neurons in vital areas of the brain - the hippocampus for one - are constantly regenerating. Survival of brand-new baby neurons is tenuous, so caution is warranted. Loss of sleep and excess stress all serve to decrease survivability. Blueberries on the other hand - give neurogenesis a boost!

Myth #2

Our brains are just massive super-computers.

Nope. Complex neural-networks we are not. Believe it not, what separates the human brain from super-computers is not the ability to learn - but the capacity to forget. Once a neural-network “learns” something, it is hard-wired into the system forever. No going back. You may now start singing the virtues of a volatile memory. No, wait, forget that!

Myth #3

The brain does not change.

On the contrary, this IS the dawning of the age of “plasticity” neuroplasticity that is. Neuroplasticity happens when all of your brain cells (neurons, glia), join forces with your circulatory system to increase your capacity for learning and memory. As a result, the absolute number of synaptic transmissions increases as does the nature of the synapse itself. Remember, synaptic transmission is the “business-end” of the neuron and is critical to enhancing brain function. But get this, overtime more neuronal refinement occurs through “synaptic pruning”. Synaptic pruning eliminates weak synaptic connections thus reinforcing the stronger ones. If that’s not brain changing, then I don’t know what is!

Myth #4

Memory loss is a “normal” part of aging.

Difficulty learning new material and a slightly longer recall time, can be seen as part of the normal aging process. Dramatic memory loss, difficulty following directions, repeating phrases or stories in the same conversation however, should not be considered normal. A simple two-minute screening test can help distinguish between the two.

Myth #5

We only use 10 percent of our brains.

Ok it’s time for this one to go. This fallacy continues to survive despite an abundance of evidence to the contrary. Everyone from Sigmund Freud to Albert Einstein is invoked to lend credibility to this myth. More recently a UK documentary by Professor John Lorber of Sheffield University featured a handful of pediatric patients with remarkably little brain tissue and yet average or even above-average intelligence. CT scanning confirmed it. This may seem convincing at first blush, but CT scanning is now ancient technology. Functional MRI images consistently show that we use all of our brains - all of the time. And with that, it’s time for the ten-percent myth to go!

Look for more brain myths to be busted. Paradigm shifts are an essential part of the scientific process - just ask Thomas Kuhn.

Strange is the new normal.

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