Mind and Heart
I have some news that might be a bit disappointing to…well, pretty much anyone who would find themselves on a blog dedicated to the mind and brain. Bear with me (or not, if you’d like, really), but this is a post primarily about the heart.
I was recently introduced via a grad student in the (yes, neuroscience) lab I work in to the latest advancement in the race to perfect an artificial heart. That link is to an NPR article that really tells you everything you need to know…and you should absolutely read it. But to summarize the details you need to know for my purposes here, the design is completely novel, and unlike previous designs, it doesn’t use nature as its inspiration.
All previous artificial hearts have attempted to mimic the beating of a natural heart, but the moving parts can wear down or cause problems such as blood clots. Instead, this implant has only two moving rotors, spinning to move the blood continuously rather than in pulses. Let that sink in for a second. Yes, transplant recipients have no heartbeat. And the first recipient lived for over a month in this state before dying of underlying problems, the “heart” still working perfectly.
So here, finally, is what all of this has to do with the brain. The main message I took home from the NPR article and subsequent discussion (aside from, as the aforementioned grad student pointed out, the fact that one with such an implant should never accidentally fall asleep in public) is that while our instinct has previously been to imitate nature, that might not always be the most efficient logistical solution. Dr. Billy Cohn, one of the creators of the device, put it very well when he pointed out that many of the earliest attempts at flying machines had flapping wings before we realized that what works for birds and insects isn’t necessarily the best answer for us.
I decided to pass this information on to my mom, a cardiac catheterization lab RN, and someone as in love with the heart as I am with the brain. Her eyes lit up when she realized that systole and diastole, that is, the heart’s pulsations serve no purpose aside from the maintenance of the heart itself, and the flow of blood—there’s no reason it can’t be continuous and steady if the heart itself is artificial. “You might start seeing these soon,” I told her, “they’re the future of your field.” “So what about you?” she replied, “How far off are artificial brains?” I rolled my eyes at her joke. Then it slowly occurred to me that, while still absurd for discussions of transplant purposes, just because something doesn’t function in the same way as its natural counterpart, doesn’t mean it isn’t the same thing.
So aren’t we already pretty close?
June 27, 2011
Also an important point to note is that the function of the heart and how it works is more or less well known and hence one can think of novel ways of implementing the same function. Whereas for the brain it’s an entirely different story, no one knows for sure how even a small part of it works and what it does!
July 13, 2011
I wonder how this new artificial heart can generate enough pressure to push blood throughout the entire body. The NPR article cites Dr. Cohn as saying that the pulsatility of the flow isn’t extremely important to anything other than the heart itself, but doesn’t the strength of the contraction from the left ventricle help the blood circulate through the body?
April 27, 2012
Clearly a fine writing here