Why Horrible Events Are Hard To Forget
by James Devitt-NYU
In a study that appears in the latest edition of the Proceedings of the National Academy of Sciences, they identify the brain mechanisms responsible for translating unpleasant experiences into long-lasting memories that are critical for survival.
This is achieved, they find, by changing the strength by which neurons are connected in the amygdala—the part of the brain involved in the formation of emotional memories.
The research tests a long-standing hypothesis on how the brain forms memories. Specifically, the findings show that this hypothesis, called Hebbian plasticity, partially explains memory formation. But the participation of other brain components is also required to remember new emotionally salient experiences.
“The convergence in the brain of weak and strong inputs—like the sight of a dog as it bites your leg—is sufficient to produce an association between the stimuli, but other mechanisms in the brain juice up the memory,” explains Joseph LeDoux, a professor in from New York University’s Center for Neural Science and the director of the study.