Everyone knows what it's like to worry about something incessantly, even if you repeatedly tell yourself to stop. While rumination and intrusive thoughts are common symptoms of certain psychiatric disorders like schizophrenia and PTSD, they also affect those suffering from even mild anxiety and depression.
Fortunately, researchers from the University of Cambridge have identified the brain neurotransmitter responsible for controlling unwanted thoughts: Gaba. "The discovery may help explain why some people can't shift persistent intrusive thoughts," writes BBC of the new study. Being able to control one's thoughts is considered "fundamental to wellbeing."
In the study, the researchers asked participants to associate a series of words with a paired but otherwise unconnected word. Next, they were asked to a respond to a red or green signal, green meaning they should recall the associated words, red meaning they should stop themselves from doing so. During the exercise, the scientists monitored the participants' brains using functional magnetic resonance imaging and magnetic resonance spectroscopy, which measures chemical changes in the brain.
In the end, those with higher concentrations of Gaba, known as the "inhibitory neurotransmitter," in the hippocampus region of the brain, were best at blocking unwanted thoughts or memories. "Our study suggests that if you could improve Gaba activity within the hippocampus, this may help people to stop unwanted and intrusive thoughts," explain the researchers. Of course, doing so is the difficult part—while Gaba supplements do exist, the research is sorely lacking, and they should only be taken after consulting your healthcare practitioner.