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Are obese brains “addicted” to sugar?
Hello everyone! I’m Crystal here with DNews. Now I don’t know about you, but I had really
strict parents and they rarely let me eat sugar as a kid. And now that I’m an adult,
candy basically makes up one of my major food groups. According to a new study out of the
University of California San Diego, the brains of some children respond differently to sugar
than others and are more likely to appear “addicted” to sugar.
The discovery that addicted brains are structurally and functionally different from non-addicted
brains is not new, but this study reveals that those neurological changes can happen
very young, while the brain is still developing.
Those of you who watch a lot of these videos probably already know that the brain matures
back to front, with the frontal cortex (which is responsible for our rational decision making
abilities) maturing last, in our early twenties. At adolescence the regions of our brains that
are responsible for emotion and “reward” (that happy feeling we get when we encounter
something we like) are fully on-line before we have the ability to regulate and control
our reactions to them and this fact has been used to explain why adolescents, who physically
appear very adult, make decisions that are so. very. dumb. (sorry mom)
Approaching obesity as a symptom of food addiction, Scientists at UCSD examined the brains of
obese and non-obese pre adolescent children using fMRI to identify any functional differences
in their response to sugar. The children’s ages ranged from 8 to 12 and they were asked
to close their eyes and focus on the taste of a sugar-water solution while they swirled
it around in their mouth.
The resulting images showed that obese children had more activity in the insular cortex and
amygdala, brain regions associated with emotion, perception, contextual awareness and taste.
But what was most surprising, is that the obese children did not show any increased
response to sugar in the striatum.
The striatum is involved in our perception of salience, which is how much an item or
experience stands out when compared to others and it is also known to play an important
role in our experience of reward so scientists were surprised to see no increase in activity
in children they tested. This result was also surprising because increased activity in the
striatum has been associated with obesity in adults.
The DA reward pathway involving the striatum, substantia nigra, nucleus accumbens and the
ventral tegmental area is the accepted neuroscientific roadmap for how we experience pleasure and
develop addictions (ask me about my thesis sometime) but we are starting to learn more
about the role of the amygdala in emotional regulation in the development of addiction
states. A recent rodent study showed that clinical activation of the amygdala in a lever
press experiment made a sugar solution MORE “ADDICTIVE” (or at least more rewarding).
So it may be that rats and children whose amygdala activation in response to sugar are
more likely to seek out sweets due to the emotional memory of the experience.
Obviously there are many causes for obesity and food addiction is just one of them. Are
scientists going down the right path? Subscribe to D News and let us know in the comments
down below! You can also come find me on twitter at PolyCrystalHD