Eating a slice of chocolate cake or spending time with a friend usually stimulates positive feelings, while getting in a car accident or anticipating a difficult exam is more likely to generate a fearful or anxious response. An almond-shaped brain structure called the amygdala is believed to be responsible for assigning these emotional reactions. Neuroscientists from MIT’s Picower Institute for Learning and Memory have now identified two populations of neurons in the amygdala that process positive and negative emotions. These neurons then relay the information to other brain regions that initiate the appropriate behavioral response.
The findings could also help scientists to better understand how mental illnesses such as depression arise, she says. Many psychiatric symptoms may reflect impairments in emotional processing. For example, people who are depressed do not find positive experiences rewarding, and people who suffer from addiction are not deterred by the negative outcomes of their behavior. Graduate student Praneeth Namburi and postdoc Anna Beyeler are the paper’s lead authors. Continue reading on MIT News.