A new idea for treating brain injury doesn't involve fixing the damaged regions. Instead, researchers want to detour neural impulses around the damage.
Scientists used to think of the brain as an collection of discrete parts, with different regions taking charge of different neural functions. Today's emerging model of brain activity indicates that even a simple act of perception or cognition involves many different brain regions. Several projects are devoted to mapping those complex webs of interconnections, collectively known as the connectome.
The current experiment on brain injury banks on the idea that a lesion in the brain may be disruptive partially because it interrupts some neural circuit. The researchers, from Case Western Reserve University and the Kansas University Medical Center, thought that a little judicious rewiring could solve the problem.
In the study, researchers caused brain injuries in rats' caudal forelimb area, which is involved in the movement of the rats' front legs. That brain region typically processes information from a sensory area that provides information about the limbs' positions, and it sends on the command to the premotor cortex, which in turn conveys the command to the spinal cord. In these injured rats, though, the signal couldn't make it past the sensory area. A rat presented with food pellets will still try to grab them, but it will grope around almost at random, and will have little success in nabbing the food.
To restore function, researchers implanted a microdevice in the rats. One set of electrodes recorded and digitized the signals in the sensory area, then the signal was routed to another set of electrodes in the premotor cortex, where they delivered precise electrical pulses. When these cyborg rats were tested for their pellet-grabbing skills, they performed almost as well as uninjured animals.
The video below tells the tale. Warning: Don't watch if you don't want to look at post-brain-surgery rats. They have a somewhat Frankenstein-like appearance.
Such technology could one day help a broad swath of people who suffer from traumatic brain injury, including football players, war veterans, trauma victims, and stroke patients.
Image and video: David J. Guggenmos et al.
Senior Editor Eliza Strickland joined IEEE Spectrum in March 2011 and was initially assigned the Asia beat. She got down to business several days later when the Fukushima Daiichi nuclear disaster began. Strickland shared a Neal Award for news coverage of that catastrophe and wrote the definitive account of the accident's first 24 hours. She next moved to the biomedical engineering beat and managed Spectrum's 2015 special report, “Hacking the Human OS." That report spawned the Human OS blog about emerging technologies that are enabling a more precise and personalized kind of medicine. The blog reports on wearable sensors, big-data analytics, and neural implants that may turn us all into cyborgs. Over the years, Strickland watched as artificial intelligence (AI) technology made inroads into the biomedical space, reporting on crossovers between AI and neuroscience research and IBM Watson's ill-fated efforts in AI health care. These days she oversees Spectrum's coverage of all things AI. Strickland has reported on science and technology for nearly 20 years, writing for such publications as Discover,Nautilus, Sierra, Foreign Policy, and Wired. She holds a master's degree in journalism from Columbia University.