Direct Alteration of Brain Cells Produces New Memories

Researchers led by Norman M. Weinberger, a research professor of neurobiology & behavior at UC Irvine, have shown that specific memories can be made by. They did this by directly altering brain cells in the cerebral cortex, which produces the predicted specific memory. According to the researchers, this is the first evidence that memories can be created by direct cortical manipulation.

During the experiment, Professor Weinberger and colleagues played a particular tone to lab rodents. They then stimulated the nucleus basalis deep within the rodent’s brains, releasing acetylcholine (ACh), a chemical involved in memory formation. That procedure increased the number of brain cells responding to the specific tone.

The next day, the scientists played many sounds to the animals and found that their respiration spiked when they recognized the particular tone, showing that specific memory content was created by brain changes directly induced during the experiment. Created memories have the same features as natural memories including long-term retention.

Memories are Made of This

“Disorders of learning and memory are a major issue facing many people and since we’ve found not only a way that the brain makes memories, but how to create new memories with specific content, our hope is that our research will pave the way to prevent or resolve this global issue,” said Weinberger. He is also a fellow with the Center for the Neurobiology of Learning & Memory and the Center for Hearing Research at UC Irvine.

The creation of new memories by directly changing the cortex is the culmination of several years of research in Weinberger’s lab implicating the nucleus basalis and ACh in brain plasticity and specific memory formation. Previously, the authors had also shown that the strength of memory is controlled by the number of cells in the auditory cortex that process a sound.

Original Study:

D. Kim, D. Pare, S. S. Nair. Assignment of Model Amygdala Neurons to the Fear Memory Trace Depends on Competitive Synaptic Interactions.
Journal of Neuroscience, 2013; 33 (36): 14354 DOI: 10.1523/JNEUROSCI.2430-13.2013