Thaindian News

Washington, Apr 14 (ANI): Scientists have identified a change in chemical influx into a specific set of neurons in the common fruit fly that is fundamental to long-term memory.

“In studying fruit flies’ learning and long-term memory storage, we observed an increase in calcium influx into a specific set of brain neurons in normal fruit flies that was absent in 26 different mutants known to impair long-term memory,” said Ron Davis, chair of the Scripps Research Department of Neuroscience, who led the study.

“This logical conclusion is that this increase, which we call a memory trace, is a signature component of long-term memory.”

The memory trace in question is an increased influx of calcium into a set of neurons after long-term memory forms in a part of the insect brain known as mushroom bodies, a pair of oversized lobes known to mediate learning and memory, particularly the memories of smell.

Increases in calcium influx also occur with learning in other animal models, Davis said, and it seems highly likely a similar correlation exists in humans.

To measure the changes in the Drosophila neurons, Davis and his colleagues used functional optical imaging, an advanced technology that his laboratory helped pioneer for the study of learning and memory.

Using protein sensors that become fluorescent when calcium levels are increased, the team was able to highlight changes in the levels of calcium influx into the mushroom body neurons in response to odor learning. These observed memory traces occur in parallel with behavioral changes.

Interestingly, these memory traces occur only with spaced conditioning - where the insects receive multiple episodes of learning but with periods of rest between each episode.

The study was recently published in The Journal of Neuroscience. (ANI)