Amputees discern familiar sensations across prosthetic hand

Medical researchers are helping restore the sense of touch in amputees. Credit: Image courtesy of Case Western Reserve University
Medical researchers are helping restore the sense of touch in amputees.
Credit: Image courtesy of Case Western Reserve University

Amputees discern familiar sensations across prosthetic hand

Patients connected to a new prosthetic system said they ‘felt’ their hands for the first time since they lost them in accidents. In the ensuing months, they began feeling sensations that were familiar and were able to control their prosthetic hands with more — well — dexterity.

Even before he lost his right hand to an industrial accident 4 years ago, Igor Spetic had family open his medicine bottles. Cotton balls give him goose bumps.
Now, blindfolded during an experiment, he feels his arm hairs rise when a researcher brushes the back of his prosthetic hand with a cotton ball.
Spetic, of course, can’t feel the ball. But patterns of electric signals are sent by a computer into nerves in his arm and to his brain, which tells him different. “I knew immediately it was cotton,” he said.
That’s one of several types of sensation Spetic, of Madison, Ohio, can feel with the prosthetic system being developed by Case Western Reserve University and the Louis Stokes Cleveland Veterans Affairs Medical Center.
Spetic was excited just to “feel” again, and quickly received an unexpected benefit. The phantom pain he’d suffered, which he’s described as a vice crushing his closed fist, subsided almost completely. A second patient, who had less phantom pain after losing his right hand and much of his forearm in an accident, said his, too, is nearly gone.
Despite having phantom pain, both men said that the first time they were connected to the system and received the electrical stimulation, was the first time they’d felt their hands since their accidents. In the ensuing months, they began feeling sensations that were familiar and were able to control their prosthetic hands with more — well — dexterity.
To watch a video of the research, click here: http://youtu.be/l7jht5vvzR4.
“The sense of touch is one of the ways we interact with objects around us,” said Dustin Tyler, an associate professor of biomedical engineering at Case Western Reserve and director of the research. “Our goal is not just to restore function, but to build a reconnection to the world. This is long-lasting, chronic restoration of sensation over multiple points across the hand.”
“The work reactivates areas of the brain that produce the sense of touch, said Tyler, who is also associate director of the Advanced Platform Technology Center at the Cleveland VA. “When the hand is lost, the inputs that switched on these areas were lost.”
How the system works and the results will be published online in the journal Science Translational Medicine Oct. 8.
“The sense of touch actually gets better,” said Keith Vonderhuevel, of Sidney, Ohio, who lost his hand in 2005 and had the system implanted in January 2013. “They change things on the computer to change the sensation.
“One time,” he said, “it felt like water running across the back of my hand.”
The system, which is limited to the lab at this point, uses electrical stimulation to give the sense of feeling. But there are key differences from other reported efforts.
First, the nerves that used to relay the sense of touch to the brain are stimulated by contact points on cuffs that encircle major nerve bundles in the arm, not by electrodes inserted through the protective nerve membranes.
Surgeons Michael W Keith, MD and J. Robert Anderson, MD, from Case Western Reserve School of Medicine and Cleveland VA, implanted three electrode cuffs in Spetic’s forearm, enabling him to feel 19 distinct points; and two cuffs in Vonderhuevel’s upper arm, enabling him to feel 16 distinct locations.
Second, when they began the study, the sensation Spetic felt when a sensor was touched was a tingle. To provide more natural sensations, the research team has developed algorithms that convert the input from sensors taped to a patient’s hand into varying patterns and intensities of electrical signals. The sensors themselves aren’t sophisticated enough to discern textures, they detect only pressure.
The different signal patterns, passed through the cuffs, are read as different stimuli by the brain. The scientists continue to fine-tune the patterns, and Spetic and Vonderhuevel appear to be becoming more attuned to them.
Third, the system has worked for 2 ½ years in Spetic and 1½ in Vonderhueval. Other research has reported sensation lasting one month and, in some cases, the ability to feel began to fade over weeks.
A blindfolded Vonderhuevel has held grapes or cherries in his prosthetic hand — the signals enabling him to gauge how tightly he’s squeezing — and pulled out the stems.
“When the sensation’s on, it’s not too hard,” he said. “When it’s off, you make a lot of grape juice.”
Different signal patterns interpreted as sandpaper, a smooth surface and a ridged surface enabled a blindfolded Spetic to discern each as they were applied to his hand. And when researchers touched two different locations with two different textures at the same time, he could discern the type and location of each.
Tyler believes that everyone creates a map of sensations from their life history that enables them to correlate an input to a given sensation.
“I don’t presume the stimuli we’re giving is hitting the spots on the map exactly, but they’re familiar enough that the brain identifies what it is,” he said.
Because of Vonderheuval’s and Spetic’s continuing progress, Tyler is hopeful the method can lead to a lifetime of use. He’s optimistic his team can develop a system a patient could use at home, within five years.
In addition to hand prosthetics, Tyler believes the technology can be used to help those using prosthetic legs receive input from the ground and adjust to gravel or uneven surfaces. Beyond that, the neural interfacing and new stimulation techniques may be useful in controlling tremors, deep brain stimulation and more.
Story Source:
The above story is based on materials provided by Case Western Reserve University. Note: Materials may be edited for content and length.

Manipulating memory with light: Scientists erase specific memories in mice

During memory retrieval, cells in the hippocampus connect to cells in the brain cortex. Credit: Photo illustration by Kazumasa Tanaka and Brian Wiltgen/UC Davis
During memory retrieval, cells in the hippocampus connect to cells in the brain cortex.
Credit: Photo illustration by Kazumasa Tanaka and Brian Wiltgen/UC Davis

Just look into the light: not quite, but researchers at the UC Davis Center for Neuroscience and Department of Psychology have used light to erase specific memories in mice, and proved a basic theory of how different parts of the brain work together to retrieve episodic memories.
Optogenetics, pioneered by Karl Diesseroth at Stanford University, is a new technique for manipulating and studying nerve cells using light. The techniques of optogenetics are rapidly becoming the standard method for investigating brain function.
Kazumasa Tanaka, Brian Wiltgen and colleagues at UC Davis applied the technique to test a long-standing idea about memory retrieval. For about 40 years, Wiltgen said, neuroscientists have theorized that retrieving episodic memories — memories about specific places and events — involves coordinated activity between the cerebral cortex and the hippocampus, a small structure deep in the brain.
“The theory is that learning involves processing in the cortex, and the hippocampus reproduces this pattern of activity during retrieval, allowing you to re-experience the event,” Wiltgen said. If the hippocampus is damaged, patients can lose decades of memories.
But this model has been difficult to test directly, until the arrival of optogenetics.
Wiltgen and Tanaka used mice genetically modified so that when nerve cells are activated, they both fluoresce green and express a protein that allows the cells to be switched off by light. They were therefore able both to follow exactly which nerve cells in the cortex and hippocampus were activated in learning and memory retrieval, and switch them off with light directed through a fiber-optic cable.
They trained the mice by placing them in a cage where they got a mild electric shock. Normally, mice placed in a new environment will nose around and explore. But when placed in a cage where they have previously received a shock, they freeze in place in a “fear response.”
Tanaka and Wiltgen first showed that they could label the cells involved in learning and demonstrate that they were reactivated during memory recall. Then they were able to switch off the specific nerve cells in the hippocampus, and show that the mice lost their memories of the unpleasant event. They were also able to show that turning off other cells in the hippocampus did not affect retrieval of that memory, and to follow fibers from the hippocampus to specific cells in the cortex.
“The cortex can’t do it alone, it needs input from the hippocampus,” Wiltgen said. “This has been a fundamental assumption in our field for a long time and Kazu’s data provides the first direct evidence that it is true.”
They could also see how the specific cells in the cortex were connected to the amygdala, a structure in the brain that is involved in emotion and in generating the freezing response.
Co-authors are Aleksandr Pevzner, Anahita B. Hamidi, Yuki Nakazawa and Jalina Graham, all at the Center for Neuroscience. The work was funded by grants from the Whitehall Foundation, McKnight Foundation, Nakajima Foundation and the National Science Foundation.

Project Manager in Focus

Role: Project Manager.

But what does that really mean??! I definitely get a few blank faces staring back at me when I try to explain my job to others, or, “Ohhhh! You’re the girl getting other people to do the work, spending the money and not doing a lot else?!” Hmmmmmm, I wish!! The reality is, most roles are multi-faceted and project management is no different, it involves layering a number of skills and qualities in order to be effective. The great thing about this job is that the skills are very much transferable. Project management is a life skill we can apply to almost any other circumstance. Everyone has a bit of a ‘project manager’ in them. Cue wails of, “Not me ! I’ m a scientist/ salesman/*insert title* ! ”. No really, it’s true. The types of activities that involve project management skills, such as communication; organisation; analysis and budgeting are very common. Times like when you have planned a birthday, organised food for a dinner party, or moved house.  I am still very much in the early stages of finding out what it means to be a PM, but what is clear is how much there is yet to learn!

So what have I been doing in August so far?  Aside from becoming scarily addicted to watching ‘Breaking Bad’ – not at my desk, of course 😉 This month I have mainly been planning for the submission of the next financial report due at the end of October. Not the most exciting task, granted, but essential for the award of further funding from the European Commission, which will enable the project to continue its research. The purpose of the report is to ensure we formally record progress and demonstrate to the European Commission that we are following the tasks laid out in the initial grant agreement and that we are on target to achieve the remaining project work.

It is hard to believe the project has been up and running for 2 years (where has the time gone?!) yet month 24 is fast approaching. My report planning involves contact with various teams within Newcastle University, including contract finance management, human resources and the research and enterprise office. I will collate all the scientific information for the report, as well as a summary of the management activities within the project which includes items such as progress with deliverables and milestones, recruitment statistics, ethics and gender information and a justification of resources.

One of the challenges of the role is to keep track of the various pieces of information arriving from different sources. The project is relatively small with 10 partners, however because 8 of the partners are based across Europe, most of the communication is done remotely. Sometimes I do crave face to face contact, particular when teleconferencing facilities play-up and Wi-Fi signal fluctuates, as often happens in my office!

The report will be submitted onto the online Research Participant Portal, which is our entry point for electronic administration of EU-funded research and innovation projects. The system is relatively easy to use and there is a plenty of guidance online which is always helpful because sometimes these newfangled systems can be a bit of a minefield!

This month I have also been liaising with our website designer to make some changes to the project website, in order to better inform and demonstrate to the public the achievements of the project.

I am also in the process of writing a programme for the next workshop to be held in October. We have a number of network-wide workshops written into the project and for those hosted by Newcastle University, I take care of the planning and organising and ensure that the delivery is successful. The next workshop will be a great practical workshop for our Marie curie fellows where they will have the opportunity to see the Skin Explant model Skimune™ pioneered by one of our partners, Alcyomics Ltd, in practice.

Well, I had better return to the tasks awaiting me at my desk, it’s been good to blog 🙂 How much do you use PM in your life both inside and outside of work? We would love to hear your comments!

Sharing my Animal Bone Marrow Transplant Workshop experience!

COMPARATIVE GENOMICS AND ANIMAL BONE MARROW TRANSPLANT WORKSHOP


When I read the invitation for this workshop, I knew at once, this is something I definitely had to go for! Considering there are numerous workshops taking place in a varied field of subjects all over the world, usually it takes a while to weigh out the pros and cons. I admit the first thing that caught my eye, was that it was taking place in Norway. I mean, honestly, how many people would say no to Oslo in summer?

However, once I actually took the time to read through the workshop program, the venue was the last thing on my mind. It just looked so enticing! The speakers were leading scientists from all over the world, specialized in my primary field of interest and one of our very own young PhD researchers was part of that mix. A large number of international conferences, workshops and meetings take place every year, so why was this any different? The number of participants! Only a dozen individuals were present, give or take a few, which meant a better chance of actually getting the speakers to learn your name – which was fine by me.

To me, that is the most important thing. Be it a conference, workshop, or seminar, the point of it is NETWORKING! To be able to talk to the people, and go beyond their work and results, and discover the journey that got them here, tap into what drives them and draw inspiration from their words, decisions and intellect. And that is EXACTLY what I got to do. To be able talk, laugh and drink with some of the greatest minds, your role models, even and go beyond the titles, is something every young researcher should experience at least once.

I learnt a lot on NK cells, animal models and my understanding on immunology and transplantation was elevated. But I learnt a LOT more, from the simple conversations with the speakers. What might have been a fleeting moment of small talk for them, seemed like a pool of knowledge and wisdom for me. All in all, this has to be the most educational workshop I’ve been to so far.

I have enclosed a couple of images from the days-

One rat with GVH disease demonstrated for the students during the practical session
One rat with GVH disease demonstrated for the students during the practical session
L-R: Erik Dissen, Bent Rolstad,  Ralf Dressel, Peter Parham
L-R: Erik Dissen, Bent Rolstad, Ralf Dressel, Peter Parham

 

 

Pranali Shah,
Early Career Researcher,
University Medical Centre Gottingen Germany

3 Reasons You Should Eat More Spicy Food

TIME

Hot peppers add a lot of flavor to our food, but they may be doing much more than just making our eyes water. New research shows they might have tumor-fighting benefits, as well. Here are a few reasons you should consider adding some spice into your diet.

It may reduce risk for tumors

A new study in mice published in the journal The Journal of Clinical Investigation found that the spicy chemical in peppers, capsaicin, can activate cell receptors in the intestinal lining, thereby creating a reaction that reduces the risk of developing tumors. The researchers suggest that capsaicin, which is also used as a analgesic by exhausting nerves so they cannot report pain, could help turn off an over-reactive receptor that might spur tumor growth. They fed capsaicin to mice genetically prone to develop more tumors and found that the capsaicin reduced tumors and extended the lives of those…

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