Rewire Your Brain: Think Your Way to a Better Life

brain - derived neurotrophic factor
(BDNF). This belongs to a family of proteins that enhance brain 
cells. BDNF has been shown to help build, grow, and maintain the 
infrastructure of cell circuitry. It is one of the hottest areas of 
research in neuroscience today, and more than a thousand articles 
have been written about its amazing fertilizer - like functions. It has 
even been called “ Miracle Grow ” by many, because when it ’ s applied 
to cells, it causes them to grow. A vivid illustration of BDNF ’ s 
super - fertilizing effect occurs when researchers sprinkle BDNF 
onto neurons in a petri dish. Those neurons sprouted new branches 
much as they do in the brain during learning and development. 
BDNF does its magic in variety of ways. It works within the 
cell to activate the genes that increase the production of proteins, 
serotonin, and even more BDNF. It binds to the receptors at the 
synapse, triggering a fl ow of ions that increases the voltage, which in 
turn strengthens the connectivity between the neurons. In general, 
BDNF prevents cells from dying and enhances their growth and 
vitality. BDNF is activated indirectly by glutamate and increases 
the production of internal antioxidants and protective proteins. It 
stimulates LTP, which is fundamental to neuroplasticity. 
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12 Rew i r e
Yo u r
B r a i n
LTP and BDNF go hand in hand. Researchers who work with 
the brains of various animals have shown that stimulating LTP by 
learning increases the BDNF levels. When researchers deprived the 
brains of BDNF, the brains also lost their capacity for LTP. 
Use strengthens connections, and nonuse weakens them. Old 
connections that are not strengthened by relationships will fade. 
Just as the brain needs the LTP mechanisms that strengthen the 
connections between neurons so that you can remember, it also 
needs those that will help it to forget. A process known as long - term 
depression (LTD) helps you to unlearn bad habits. (Note: LTD has 
nothing to do with the emotional state called depression.) LTD helps 
you to weaken the connections between the neurons that support 
an old habit. The weakening of old connections gives you more 
available neurons to use for the new connections that you establish 
with LTP. 
To understand this principle, consider that the age at which you 
learn a language affects whether you speak with an accent. If you 
learn a new language while in your twenties, it ’ s highly probable 
that you will speak that new language with an accent from your 
fi rst language. If you learn a new language at age nine, however, you 
probably won ’ t have an accent tinged by your fi rst language. When 
you learn a new language as an adult, the neurons that have always 
connected to make specifi c sounds tend to continue to fi re together 
even when you try to make different but related sounds. 
T he more you talk to people who don ’ t share your accent, the 
greater is the chance that your accent will fade. For example, both 
my parents grew up in the Greater Boston area. A few years after 
I was born, my family moved west. My parents gradually lost their 
Boston accents as they spoke with people who had moved west from 
all over the country or who had grown up there. 
When you develop new ideas or insights, change in your brain 
occurs much more quickly than when you learn a new language or 
lose an accent. Certain parts of the brain are very talented at put-
ting information together quickly so that you can make decisions 
without mulling things over for hours or even days. 
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F i r i n g t h e R i g h t C e l l s To g e t h e r
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The discovery of