In the quest to get ready for summer, many of us want to get in better shape by exercising a bit more and maybe losing a few pounds. But when you’re confronted with stacks of candy bars at the supermarket checkout, sometimes it can be a bit too tempting to cheat on our diet. Sure, added willpower would be nice, but wouldn’t it be great if we could just reprogram our brain to no longer crave — or even actively reject — sugar? That’s a possibility hinted at in a new piece of research coming out of Columbia University’s Zuckerman Institute.
Researchers there have identified two regions of the brain that respond to sweet and bitter tastes, and modified these areas in mice to provoke different reactions. In their study, they were able to make mice respond to ordinary water as though it was sugar, make bitterness an attractive taste, and turn sweetness into a negative experience.
“Our current study aimed to decipher how the identity and valence of sweet and bitter taste were processed at the insula cortex and amygdala,” Dr. Li Wang, a postdoctoral research scientist in the Zuker Lab and the paper’s first author, told Digital Trends. “With viral tracing tools, we labeled these sweet and bitter cortical neurons in green and red, and mapped their projections brain-wide using one of the latest whole-brain clearing and imaging techniques. It is interesting to find that sweet and bitter neurons separately projected to two different subregions of amygdala, an important brain structure for judging and assigning the value of a sensory stimulus. By switching on or off this cortico-amygdalar circuit, it is [possible] to change the valence of taste or manually assign a new valence.”
Valence in this psychological sense refers to the inherent attractiveness or averseness of a particular taste quality. That means that it could one day be possible to use this research to alter the emotional component of eating certain foods. That might conceivably be used to help people with a range of eating disorders.
“Looking from the long-term view, it [may] help to address the obesity issue, if we could have a way to change humans’ preference of sugar,” Wang said. “In the [future], we will expand our research to other brain structures and aim to unravel how these regions drive different aspects of the taste behavioral responses.”
A paper describing the work was recently published in the journal Nature.
