First-of-its-Kind Video Shows Memories Forming in the Brain

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Researchers in New York have released video footage of memories being formed in the brain.

The video shows molecules vital to making memories moving through tissue in a mouse's brain channels to form new memories.

A scientific team from the Albert Einstein College of Medicine at Yeshiva University in the Bronx gave the important molecules a fluorescent hue so they could be tracked traveling in real time through living brain tissue.

The researchers in a statement asserted the new insights provided by the video, "a technological tour de force never before achieved in animals," will have a major impact on the understanding of how the brain works.

"Efforts to discover how neurons make memories have long confronted a major roadblock: Neurons are extremely sensitive to any kind of disruption, yet only by probing their innermost workings can scientists view the molecular processes that culminate in memories," the researchers said.

In order to see the memory process in action, Einstein scientists stimulated neurons from a mouse's hippocampus -- where memories are made as well as stored -- and then watched as beta-actin mRNA molecules formed in neurons and traveled along dendrites, the branched tissue projecting from neurons.

"It's noteworthy that we were able to develop this mouse without having to use an artificial gene or other interventions that might have disrupted neurons and called our findings into question," said study author Robert Singer.

Research team members found the mRNA in neurons is regulated through a process they described as "masking" and "unmasking," which allows memory-making beta-actin protein to synthesize at specific times and places and in specific amounts.

"This observation -- that neurons selectively activate protein synthesis and then shut it off -- fits perfectly with how we think memories are made," said Singer. "Frequent stimulation of the neuron would make mRNA available in ... controlled bursts, causing beta-actin protein to accumulate precisely where it's needed to strengthen the synapse."

Singer said he and his research colleagues are developing new technologies for imaging neurons in the intact brains of living mice.

Their new goal is to produce infrared fluorescent proteins that emit light able to pass through tissue, as the hippocampus resides deep within the brain.

Another option for the researchers, said Singer, would be inserting a fiberoptic device into the brain, which could then be used to view hippocampal neurons.