The seat of worry is the amygdala, an almond-shaped structure beside the hippocampus that is associated with emotional responses such as fear and anxiety. “It's the heart and soul of the [nervous] system—it detects a dangerous situation and causes you to react,” says Joseph LeDoux, PhD, an endowed professor of science at NYU, who has spent most of his career studying anxiety and the brain.
Two areas of the amygdala generate reactions. The lateral nucleus processes the sensory information associated with anxiety—hearing a strange sound, say, or not being able to see clearly—and the central nucleus (upon being activated by the stimulus) sends a signal to the motor system to “freeze.” It also triggers the release of stress hormones, affecting the autonomic nervous system, which regulates breathing, heart rate, and blood pressure. The result of all this activity is to feel anxious, says Dr. LeDoux, who is also director of the Emotional Brain Institute at NYU.
Some people get stuck in “freeze” mode, so anytime they encounter the same stimulus, they panic. “We saw that in animal studies. Most rats, when given an electric shock, react by moving elsewhere,” he says. “But some rats just took the shock over and over. They were frozen, or stuck.” Dr. LeDoux was ultimately able to alter the animals' reaction by removing a part of their central nuclei.
Anti-anxiety drugs, says Dr. LeDoux, are a Band-Aid solution. “Drugs make people less responsive, which doesn't really solve the problem,” he says. He compares it to dining at a restaurant where the music is too loud. “Medications can make you less reactive to the volume, but they won't change the fact that it's just too noisy.”
A better way to treat anxiety might be to reduce the overall state of arousal in the amygdala and the resulting behavioral reactions, says Dr. LeDoux. “One method for doing this is to flash a light in a person's eye so fast they don't even realize it's there,” he explains. “This stimulus goes into the amygdala and activates it unconsciously. If you repeat it over and over, you train the amygdala to not react in the same way.”
Several studies have been conducted on the association between light and the amygdala, including one published in Frontiers in Psychology in 2021 that found the flash technique to be effective in reducing the vividness of and emotional reaction to disturbing memories. If the reaction of the amygdala can be tweaked, Dr. LeDoux says, people may be able to take the first steps toward conquering anxiety.
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