Notably, cell-specific degeneration is a unifying feature of all the neurodegenerative diseases. Dopamine-producing neurons in the substantia nigra region of the brain deteriorate in Parkinson's disease, motor neurons of the spinal cord and motor cortex degenerate in ALS and specific memory-forming medial temporal lobe neurons die in early Alzheimer's disease.
"We hope to add von Economo neurons to that list," says Seeley. "It's a pretty important list to fill in, but for FTD there just hasn't been a good candidate until now. We think we've found it, and that is the most exciting part of the discovery for those of us who treat patients."
At the same time, he says, the finding "gives us a sense that we might be able to start to figure out what makes us unique as humans, what makes our brains different from those of other species. And that's pretty exciting, too."
Bruce Miller, MD, the A.W. & Mary Margaret Clausen Distinguished Professor of Neurology, director of the UCSF Memory and Aging Center and a co-author of the study, concurs.
"The social and behavioral skills that you lose in frontotemporal dementia are so characteristically human, or at least strongly associated with higher primates," he reflects.
"I think it's fascinating from an evolutionary perspective that we have these new neurons that are involved in social behavior that are selectively vulnerable in the second major degenerative disorder."
Notably, VENs are located in regions of the brain that are in a good position to transmit raw emotional signals to other brain centers. In addition, VENs have characteristics that suggest they play a role in analyzing sparse inputs and sending rapid output signals, further supporting the idea that they may impact behavior.
Source:University of California - San Francisco