THE body’s own opioid system acts as a brake on how much fear we feel – a discovery which may shine light on the neural mechanisms behind anxieties, phobias and even post-traumatic stress disorder.
Pairing an innocuous stimulus such as a sound with something undesirable, such as a painful shock, can trigger a “conditioned fear” response in the form of sweaty palms and a racing heart. With time, the stimulus alone is enough to trigger the response.
Perplexingly, when people dread something painful, they come to feel less pain the more they’re exposed to it.
In rodents natural opioids blunt pain…
