A team of scientists at the University of California, Irvine has proposed a new theory that challenges the current understanding of how the brain stores long-term memories. The prevailing theory, known as the synaptic plasticity hypothesis, suggests that memories are formed by strengthening the connections between neurons in the brain.

The new theory, published in the journal Nature Reviews Neuroscience, argues that memories are not stored in individual neurons or synaptic connections, but rather in a distributed network of brain regions. The researchers propose that memories are represented by the coordinated activity of multiple neurons and that the strength of a memory is determined by the number of neurons involved in the network.

This distributed network model is supported by a growing body of evidence from neuroimaging studies, which show that memories are associated with the activation of multiple brain regions, rather than being localized to a single area. Additionally, studies have shown that the strength of a memory can be increased by stimulating multiple neurons in the network.

The new theory has implications for understanding a variety of brain functions, including memory, learning, and disease. It could also lead to the development of new treatments for memory disorders such as Alzheimer's disease.

Key points:

- Current view: Memories are stored in the brain by strengthening connections between neurons.

- New theory: Memories are stored in a distributed network of brain regions, with the strength of a memory being determined by the number of neurons involved in the network.

- Evidence: Supported by neuroimaging studies showing memories associated with the activation of multiple brain regions, and studies showing memory strength can be increased by stimulating multiple neurons.

- Implications: Changes understanding of brain functions like memory, learning, and disease, potentially leading to new treatments for memory disorders.