Long-Term Potentiation is a memory mechanism

Brain Blogger - Memories are Made of These

Scientists have been looking for stronger evidence that Long-Term Potentiation (LTP) is a mechanism constitutive of memory. LTP is a brain-behavior whereby two (or more) neurons will come to activated synchronously when they are continually stimulated synchronously. In other words, neurons come to be associated with one another (by improving their transmission between each other) when they are activated repeatedly synchronously. In this study, scientists created a fear of a bell in rats by associating it with a shock to the rats' feet. Scientists understand a fear response in lab rats because they "freeze" when afraid. Soon, the bell itself induced the freezing. Scientists conducted a similar training with a blue light instead of a bell, again eventually inducing the fear response to the blue light alone. The blue light stimulated a portion of the rats' amygdala that had been previously altered so as to create pathways in the brain based on light-sensitivity. The stimulated portions of the amygdala then showed evidence of LTP. Perhaps even more interestingly, when scientists used light to counter the effects of LTP (a mechanism called Long-Term Depression), the fear response was not observed. Thus a strong connection between behavioral memory (fear) and LTP is established. This study further strengthens the case that LTP is a critical mechanism underwriting memory.