WASHINGTON, Oct. 19 - One of the main techniques for measuring and monitoring mental activity, called functional near infrared spectroscopy (fNIRS), can often be impaired because a person's hair gets in the way. But now, thanks to a team of researchers at the University of Texas at Dallas and the University of Texas at Arlington, a novel device called a "brush optrode" is providing increased sensitivity with fiber tips designed to thread through hair to enhance scalp contact.
Details of the device will be presented at the Optical Society's (OSA) 94th annual meeting, Frontiers in Optics (FiO) 2010, at the Rochester Riverside Convention Center in Rochester, N.Y., from Oct. 24.
fNIRS is a noninvasive optical technique that measures oxygen levels in the brain to chart neurological activity. The difference between oxygenated hemoglobin and deoxygenated hemoglobin can be used as a correlate of brain activity. Using fNIRS, this difference in blood oxygen level is determined using a relative spectroscopic measurement at two near infrared wavelengths.
"Using light to measure a person's thinking pattern has numerous advantages over EEGs, including ease of use, reliability, cost, portability and MRI compatibility," says Duncan MacFarlane, professor of electrical engineering in the Erik Jonsson School of Engineering and Computer Science at the University of Texas at Dallas.
"The conventional fibers used in fNIRS systems terminate in a large, flat bundle, and it is easy for a patient's hair to get in the way and block the signal," he explains. "So we developed a new tip for the fNIRS fibers -- a brush optrode that slides the fibers between the hair follicles. Signal levels increase 3- to 5-fold, and patients report that the brush optrode is considerably more comfortable than the conventional fiber ends. And the brush optrode is easier to set up, which saves time and money."
This research is expected to open the door to portable, easy-to-use, high-density optical scanning of brain activity. For example, the University of Texas researchers' work focuses on the imaging of changes in cortical plasticity as a function of impairment severity in children with cerebral palsy. According to Georgios Alexandrakis, a member of the UT Arlington research team, the newly developed optrodes could also be potentially useful to a variety of fNIRS projects, including the evaluation of recovery from stroke, changes in brain activity in Alzheimer's patients, the perception of pain, and for assessing developmental changes in normal and impaired pediatric populations.
The presentation, "Improved fNIRS Using a Novel Brush Optrode" is at 12:30 p.m. on Tuesday, Oct. 26.
About the Meeting
Frontiers in Optics 2010 is OSA's 94th Annual Meeting and is being held together with Laser Science XXVI, the annual meeting of the American Physical Society (APS) Division of Laser Science (DLS). The two meetings unite the OSA and APS communities for five days of quality, cutting-edge presentations, fascinating invited speakers and a variety of special events spanning a broad range of topics in physics, biology and chemistry. FiO 2010 will also offer a number of Short Courses designed to increase participants' knowledge of a specific subject while offering the experience of insightful teachers. An exhibit floor featuring leading optics companies will further enhance the meeting.
Meeting home page
EDITOR'S NOTE: A Press Room for credentialed press and analysts will be located in Aqueduct AB of the Rochester Riverside Convention Center, Sunday through Thursday. Those interested in obtaining a press badge for FiO should contact OSA's Lyndsay Basista at +1 202.416.1930 or firstname.lastname@example.org.
Uniting more than 106,000 professionals from 134 countries, the Optical Society (OSA) brings together the global optics community through its programs and initiatives. Since 1916 OSA has worked to advance the common interests of the field, providing educational resources to the scientists, engineers and business leaders who work in the field by promoting the science of light and the advanced technologies made possible by optics and photonics. OSA publications, events, technical groups and programs foster optics knowledge and scientific collaboration among all those with an interest in optics and photonics. For more information, visit www.osa.org.