The doctor pulled out the four main nerves that used to connect to the patient’s damaged arm and put them beneath the skin in his chest. The prosthetic has a device that presses on the chest to communicate information from the prosthetic.
http://www.chicagotribune.com/news/nationworld/chi-0506230208jun23,1,7950510.story
This Tech Review feature story details the experience of the first patient using the Donoghue group’s (Brown Univ) implantable motor cortex prosthetic for computer control.
Although the author interviews a lot of people involved with the project, not too many specifics of the recording device or control algorithms are given. What is interesting is to see the disagreement from some other top PIs in the field (in particular, Nicolelis), who believe that Cyberkinetics is skipping some steps in putting this device in human trials. That is, present-day crude neural prosthetics should not be used on anyone except the most “locked-in” of patients; the patient in the BrainGate trial is apparently a quadraplegic but has full facial control.
I can’t say that I disagree. I’m not sure putting the sum of patient benefits and scientific value justify the danger. Donoghue’s purported question that he believes would only be answered by human trials (Would motor neurons work after prolonged paralysis?) seem answerable with animal models. Here’s the real question: Why didn’t they get a patient who really could benefit from this technology, ie. someone “locked-in”?
This review article (NRN Jan 2005) has a nice summary of cross-modal neuroplasticity in humans, mostly dealing with how occipital cortex (primarily visual for normals) takes over tactile and auditory processing duties in blind patients. The authors go on to speculate that these neuroplasticity insights could be applied to neural prothestic users to speed adaptation to their new sensory apparati, like combining tactile/auditory information with the prosthetic based stimulation. There’s also a nice comparison of visual implants at several levels, including retina, optic nerve, and cortex.
Cutting edge research groups.
Where in the world is the cutting edge in neural prosthetic design taking place?
(more…)
Neat article in today’s NYT on how a tongue stimulator can re-route many different sensory modalities. The most dramatic example (which the article focuses on) is how the device helps rehabilitate a patient with extensive vestibular damage and trains her brain to use whatever vestibular neurons she has left by this alternative (somatosensory) pathway. Click below for the full article.
(more…)
University of Florida has an Oct 21 press release about Thomas DeMarse’s work in hybrots, that is, cultured neurons interacting with a computer via an MEA to control an avatar in a simulated world. In this case, the neurons are flying a plane in a flight simulation program.
It looks from the press release that he has got the animat to actually learn to fly a plane (i.e. got input about the simulated environment and controlled a simulator joystick to keep the plane steady!
Unfortunately he doesn’t describe what kind of learning rule/feedback was used, so I guess we’ll have to wait for the paper to see how much excitement is justified.
P.S. there’s also a lively discussion on SlashDot about this press release.
In this week’s Science, Richard Andersen’s lab shows the first use of a region (relatively) distant from primary motor areas for brain readout in a reaching task. Using a very small number of neurons (8-16 cells), the investigators were able to achieve a 60-70% accuracy in predicting reach movements to a particular target (out of 8 total targets). Read on for the abstract or here for the full article.
(more…)
Looks like John Donoghue’s company will be doing human trials this year in quadraplegics! Cyberkinetics is one of the first companies (Neural Signals Inc. was the first, I think) to actually do human implants for read-out (versus other therapeutics like deep brain stimulation.
What’s really remarkable here is the speed at which research has moved to medicine. (the nature paper is from 2002!) This is how things should be.
(more…)