Navigation Links
A brain-recording device that melts into place

Scientists have developed a brain implant that essentially melts into place, snugly fitting to the brain's surface. The technology could pave the way for better devices to monitor and control seizures, and to transmit signals from the brain past damaged parts of the spinal cord.

"These implants have the potential to maximize the contact between electrodes and brain tissue, while minimizing damage to the brain. They could provide a platform for a range of devices with applications in epilepsy, spinal cord injuries and other neurological disorders," said Walter Koroshetz, M.D., deputy director of the National Institute of Neurological Disorders and Stroke (NINDS), part of the National Institutes of Health.

The study, published in Nature Materials, shows that the ultrathin flexible implants, made partly from silk, can record brain activity more faithfully than thicker implants embedded with similar electronics.

The simplest devices for recording from the brain are needle-like electrodes that can penetrate deep into brain tissue. More state-of-the-art devices, called micro-electrode arrays, consist of dozens of semi-flexible wire electrodes, usually fixed to rigid silicon grids that do not conform to the brain's shape.

In people with epilepsy, the arrays could be used to detect when seizures first begin, and deliver pulses to shut the seizures down. In people with spinal cord injuries, the technology has promise for reading complex signals in the brain that direct movement, and routing those signals to healthy muscles or prosthetic devices.

"The focus of our study was to make ultrathin arrays that conform to the complex shape of the brain, and limit the amount of tissue damage and inflammation," said Brian Litt, M.D., an author on the study and an associate professor of neurology at the University of Pennsylvania School of Medicine in Philadelphia. The silk-based implants developed by Dr. Litt and his colleagues can hug the brain like shrink wrap, collapsing into its grooves and stretching over its rounded surfaces.

The implants contain metal electrodes that are 500 microns thick, or about five times the thickness of a human hair. The absence of sharp electrodes and rigid surfaces should improve safety, with less damage to brain tissue. Also, the implants' ability to mold to the brain's surface could provide better stability; the brain sometimes shifts in the skull and the implant could move with it. Finally, by spreading across the brain, the implants have the potential to capture the activity of large networks of brain cells, Dr. Litt said.

Besides its flexibility, silk was chosen as the base material because it is durable enough to undergo patterning of thin metal traces for electrodes and other electronics. It can also be engineered to avoid inflammatory reactions, and to dissolve at controlled time points, from almost immediately after implantation to years later. The electrode arrays can be printed onto layers of polyimide (a type of plastic) and silk, which can then be positioned on the brain.

To make and test the silk-based implants, Dr. Litt collaborated with scientists at the University of Illinois in Urbana-Champaign and at Tufts University outside Boston. John Rogers, Ph.D., a professor of materials science and engineering at the University of Illinois, invented the flexible electronics. David Kaplan, Ph.D., and Fiorenzo Omenetto, Ph.D., professors of biomedical engineering at Tufts, engineered the tissue-compatible silk. Dr. Litt used the electronics and silk technology to design the implants, which were fabricated at the University of Illinois.

Recently, the team described a flexible silicon device for recording from the heart and detecting an abnormal heartbeat.

In the current study, the researchers approached the design of a brain implant by first optimizing the mechanics of silk films and their ability to hug the brain. They tested electrode arrays of varying thickness on complex objects, brain models and ultimately in the brains of living, anesthetized animals.

The arrays consisted of 30 electrodes in a 5x6 pattern on an ultrathin layer of polyimide with or without a silk base. These experiments led to the development of an array with a mesh base of polyimide and silk that dissolves once it makes contact with the brain so that the array ends up tightly hugging the brain.

Next, they tested the ability of these implants to record the animals' brain activity. By recording signals from the brain's visual center in response to visual stimulation, they found that the ultrathin polyimide-silk arrays captured more robust signals compared to thicker implants.

In the future, the researchers hope to design implants that are more densely packed with electrodes to achieve higher resolution recordings.

"It may also be possible to compress the silk-based implants and deliver them to the brain, through a catheter, in forms that are instrumented with a range of high performance, active electronic components," Dr. Rogers said.


Contact: Daniel Stimson
NIH/National Institute of Neurological Disorders and Stroke

Related biology news :

1. New studies help establish potential of artificial liver support devices
2. Incorporating biofunctionality into nanomaterials for medical, health devices
3. Sorting device for analyzing biological reactions puts the power of a lab in a researcher’s pocket
4. Stitching together lab-on-a-chip devices with cotton thread and sewing needles
5. Ardiem Medical obtains non-exclusive license for neuromodulation devices
6. New ORNL sensor exploits traditional weakness of nano devices
7. Silver nanoparticles may one day be key to devices that keep hearts beating strong and steady
8. Pitt-led team gets $5.6 million contract for heart assist device for infants and toddlers
9. Habit-learning device will lower energy bills under new clean energy cashback scheme
10. New adhesive device could let humans walk on walls
11. Novel NIST connector uses magnets for leak-free microfluidic devices
Post Your Comments:
Related Image:
A brain-recording device that melts into place
(Date:11/17/2015)... LIVERMORE, Calif. , Nov. 17, 2015  Vigilant ... has joined its Board of Directors. ... Vigilant,s Board after recently retiring from the partnership at ... owning 107 companies with over $140 Billion in revenue.  ... performance improvement across all the TPG companies, from 1997 ...
(Date:11/12/2015)... LONDON , Nov. 11, 2015   ... and reliable analytical tools has been paving the ... and qualitative determination of discrete analytes in clinical, ... sensors are being predominantly used in medical applications, ... and environmental sectors due to continuous emphasis on ...
(Date:11/9/2015)... , Nov. 9, 2015  Synaptics Inc. (NASDAQ: ... today announced broader entry into the automotive market with ... match the pace of consumer electronics human interface innovation. ... are ideal for the automotive industry and will be ... Europe , Japan ...
Breaking Biology News(10 mins):
(Date:11/25/2015)... -- Orexigen® Therapeutics, Inc. (Nasdaq: OREX ) today ... discussion at the Piper Jaffray 27th Annual Healthcare Conference ... is scheduled for Wednesday, December 2, at 8:00 a.m. ... will be available for 14 days after the event.  ... Corporate Communications and Business Development , BrewLife(858) 875-8629 ...
(Date:11/24/2015)... ... November 24, 2015 , ... The United States Golf Association ... 2016 USGA Green Section Award. Presented annually since 1961, the USGA Green Section Award ... work with turfgrass. , Clarke, of Iselin, N.J., is an extension specialist ...
(Date:11/24/2015)... Mass. (PRWEB) , ... November 24, 2015 , ... ... to maintain healthy metabolism. But unless it is bound to proteins, copper is ... of Health (NIH), researchers at Worcester Polytechnic Institute (WPI) will conduct a systematic ...
(Date:11/24/2015)... --> --> ... Synthesis Market by Product & Services (Primer, Probe, Custom ... RNAi), End-User (Research, Pharmaceutical & Biotech, Diagnostic Labs) - ... is expected to reach USD 1,918.6 Million by 2020 ... of 10.1% during the forecast period. Browse ...
Breaking Biology Technology: