Scientists have unexpectedly validated the ancient saying: "The brain is like muscles."

Many people liken the brain to muscles, using phrases like "use it or lose it" and discussing ways to enhance cognitive abilities. Although brain tissue is fundamentally different from muscle, recent studies indicate that some of its functions may bear a remarkable resemblance to muscle behavior, reports IFLScience.

A study conducted by scientists from the Howard Hughes Medical Institute identified a mechanism in brain cells that mirrors how muscles receive signals to contract.

The research, led by Lorena Benedetti, focused on the endoplasmic reticulum (ER) — a cellular structure crucial for protein synthesis and regulation.

Benedetti observed a distinct ladder-like arrangement of molecules along the dendrites, which are branched extensions of nerve cells. A similar pattern was independently noted by Stefan Zaalfeld in images of brain cells from flies, drawing the attention of senior researcher Jennifer Lippincott-Schwartz.

The similarity of these patterns to structures found in muscle cells prompted further investigation. In muscle tissue, the proteins known as junctophilins facilitate contact between the ER and the cell membrane, allowing calcium release to trigger contraction.

The team discovered that junctophilins also exist in dendrites, forming structured contact points between the ER and the outer membrane. This suggested their potential role in signaling within nerve cells.

Benedetti and her colleagues proposed that these regions act as amplifiers, helping calcium signals travel effectively over long distances within neurons.

When nerve signals stimulate the release of calcium from the ER, the protein CaMKIII is activated. This protein influences the strength of signals transmitted along the neuron, akin to a series of amplifiers along a communication cable. The findings offer new insights into how learning and memory processes function at the cellular level.

As Lippincott-Schwartz notes, even Albert Einstein once compared thinking to training muscles, and modern science may be uncovering a deeper connection between these two processes.

This discovery could have significant implications for understanding memory-related conditions such as dementia and for improving approaches to neurological research.