Scientists at the University of Virginia School of Medicine have developed a tool to monitor communications within the brain, and their creation has already offered an explanation for why Alzheimer’s drugs have limited effectiveness and why patients get much worse after going off of them, according to a news release.
The new method lets scientists examine transmissions inside the brain at both the microscopic level and the far, far smaller nanoscopic level. It combines a biological “sensor” with two different forms of imaging.
The approach can quantify “neuromodulatory” transmissions, which are associated with major brain disorders, including addiction, Alzheimer’s, depressive disorders and schizophrenia. They’re also linked to autism, epilepsy, eating disorders and sleep disorders. Neuromodulatory transmissions are the “slower” transmissions in the brain. They’re typically thought to involve lots of neurons in large regions. That’s in contrast to the much faster transmissions that happen neuron-to-neuron.
But the new tool has already shown it is not that simple.
In Alzheimer’s disease, the researchers discovered a surprising degree of “fine control and precision” in the supposedly shotgun neuromodulatory transmissions. Widely used Alzheimer’s drugs known as acetylcholinesterase inhibitors may inhibit this precise communication, the scientists report. That may explain the limited effectiveness of the drugs.
The researchers went on to identify potential changes in the brain that could be brought about by long-term use of the drugs, which could explain why patients often get much worse when they stop taking them.
