Featured Research

from universities, journals, and other organizations

Thinner probe array that uses silicon-based microstructure could underpin safer neural implants

Date:
March 30, 2014
Source:
The Agency for Science, Technology and Research (A*STAR)
Summary:
Neural probe arrays are expected to significantly benefit the lives of amputees and people affected by spinal cord injuries or severe neuromotor diseases. By providing a direct route of communication between the brain and artificial limbs, these arrays record and stimulate neurons in the cerebral cortex.

The compact neural probe array consists of a three-dimensional probe array, a custom 100-channel neural recording chip and a flexible polyimide polymer cable.
Credit: 2014 A*STAR Institute of Microelectronics

Neural probe arrays are expected to significantly benefit the lives of amputees and people affected by spinal cord injuries or severe neuromotor diseases. By providing a direct route of communication between the brain and artificial limbs, these arrays record and stimulate neurons in the cerebral cortex.

The need for neural probe arrays that are compact, reliable and deliver high performance has prompted researchers to use microfabrication techniques to manufacture probe arrays. Now, a team led by Ming-Yuan Cheng from the A*STAR Institute of Microelectronics, Singapore, has developed a three-dimensional probe array for chronic and long-term implantation in the brain1. This array is compact enough to freely float along with the brain when implanted on the cortex.

The neural probe array needs to be implanted in the subarachnoid space of the brain, a narrow region of 1-2.5 millimeters in depth that lies between the pia mater and dura mater brain meninges. "A high-profile array may touch the skull and damage the tissue when relative micromotions occur between the brain and the probes," explains Cheng. To avoid this problem, the array should be as thin as possible.

Existing approaches produce low-profile arrays using microscopic electrodes machined from a silicon substrate. These approaches, however, restrict the maximum probe length to the thickness of the substrate and the number of recording electrodes. Other methods generate three-dimensional arrays from silicon-supported two-dimensional probes. Complex and expensive to fabricate, these arrays are too bulky because the silicon support also incorporates the application-specific integrated circuit (ASIC) chip for neural recording.

Cheng and colleagues fabricated two-dimensional probes and inserted them into a thin slotted silicon platform for assembly (see image). To produce a three-dimensional probe array, they joined this assembly to the recording chip. Instead of being aligned, however, the team found that the contacts of the probe electrodes and recording chip were orthogonally arranged with respect to each other, resulting in mismatched planes.

"To solve this issue, the team manufactured a silicon-based connector, or interposer, that electrically linked these components," says Cheng. "This innovative microassembly effectively controls the final height of the array to within 750 micrometers."

Compared with commercial neural probes, the new array exhibited competitive electrical properties, including electrode impedance. Moreover, biocompatibility tests showed that the presence of array components did not rupture cell membranes or suppress cell growth. The team is currently refining their approach to integrate the array with a wireless recording chip and make the assembly fully implantable.


Story Source:

The above story is based on materials provided by The Agency for Science, Technology and Research (A*STAR). Note: Materials may be edited for content and length.


Journal Reference:

  1. Ming-Yuan Cheng, Minkyu Je, Kwan Ling Tan, Ee Lim Tan, Ruiqi Lim, Lei Yao, Peng Li, Woo-Tae Park, Eric Jian Rong Phua, Chee Lip Gan, Aibin Yu. A low-profile three-dimensional neural probe array using a silicon lead transfer structure. Journal of Micromechanics and Microengineering, 2013; 23 (9): 095013 DOI: 10.1088/0960-1317/23/9/095013

Cite This Page:

The Agency for Science, Technology and Research (A*STAR). "Thinner probe array that uses silicon-based microstructure could underpin safer neural implants." ScienceDaily. ScienceDaily, 30 March 2014. <www.sciencedaily.com/releases/2014/03/140330193646.htm>.
The Agency for Science, Technology and Research (A*STAR). (2014, March 30). Thinner probe array that uses silicon-based microstructure could underpin safer neural implants. ScienceDaily. Retrieved July 30, 2014 from www.sciencedaily.com/releases/2014/03/140330193646.htm
The Agency for Science, Technology and Research (A*STAR). "Thinner probe array that uses silicon-based microstructure could underpin safer neural implants." ScienceDaily. www.sciencedaily.com/releases/2014/03/140330193646.htm (accessed July 30, 2014).

Share This




More Mind & Brain News

Wednesday, July 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

It's Not Just Facebook: OKCupid Experiments With Users Too

It's Not Just Facebook: OKCupid Experiments With Users Too

Newsy (July 29, 2014) If you've been looking for love online, there's a chance somebody has been looking at how you're looking. Video provided by Newsy
Powered by NewsLook.com
How Your Face Can Leave A Good Or Bad First Impression

How Your Face Can Leave A Good Or Bad First Impression

Newsy (July 29, 2014) Researchers have found certain facial features can make us seem more attractive or trustworthy. Video provided by Newsy
Powered by NewsLook.com
Losing Sleep Leaves You Vulnerable To 'False Memories'

Losing Sleep Leaves You Vulnerable To 'False Memories'

Newsy (July 27, 2014) A new study shows sleep deprivation can make it harder for people to remember specific details of an event. Video provided by Newsy
Powered by NewsLook.com
University Quiz Implies Atheists Are Smarter Than Christians

University Quiz Implies Atheists Are Smarter Than Christians

Newsy (July 25, 2014) An online quiz from a required course at Ohio State is making waves for suggesting atheists are inherently smarter than Christians. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins