The way forward for electroencephalography (EEG) monitoring might quickly seem like a strand of hair. Rather than the normal steel electrodes, an internet of wires and sticky adhesives, a workforce of researchers from Penn State created a hairlike system for long-term, non-invasive monitoring of the mind’s electrical exercise. The light-weight and versatile electrode attaches on to the scalp and delivers secure, high-quality recordings of the mind’s indicators.
EEG is essential for diagnosing and assessing neurological situations like epilepsy and mind accidents. In some circumstances, clinicians want to observe mind waves for longer durations of time, for instance, to guage seizures, sleep issues and situations that have an effect on the blood vessels and blood circulation within the mind.
The researchers described the brand new electrodes, which had been proven to keep up secure efficiency for over 24 hours of steady put on, in a research revealed within the journal npc biomedical improvements. This expertise holds promise to be used in client well being and wellness merchandise, along with medical well being care software, in accordance with the researchers.
“This electrode permits for extra constant and dependable monitoring of EEG indicators and might be worn with out being noticeable, which reinforces each performance and affected person consolation,” mentioned Tao Zhou, Wormley Household Early Profession Professor of engineering science and mechanics and senior writer on the paper.
EEG monitoring is a broadly used methodology to measure the mind’s electrical exercise, Zhou defined. Small steel electrodes are positioned on the scalp and choose up the faint electrical impulses generated by cells within the mind. The electrodes are hooked up to wires which can be then related to a machine that shows the mind’s exercise as patterns that seem like waves.
The standard EEG monitoring course of, nevertheless, is usually a cumbersome — and typically messy — affair. Its limitations make it troublesome to make use of for steady, long-term monitoring.
To get a very good recording of the mind’s exercise, the electrodes want to adapt to the scalp. Any gaps between the electrode and the pores and skin or dense hair can diminish the standard of the recorded sign. Researchers and clinicians should apply gels to the scalp to keep up good surface-to-surface contact between the electrodes and pores and skin and sign high quality. For some folks, although, the gels may cause pores and skin irritation.
It is a time-consuming course of that should be repeated when the gels dry out, particularly for somebody must be monitored repeatedly or over the course of a number of classes. The appliance and re-application course of is imprecise, too, and may end up in completely different quantities of gel used on the electrodes.
“This may change the impedance — or interface — between the electrodes and the scalp and it will possibly have an effect on the mind sign that is recorded,” Zhou mentioned. “We additionally do not at all times apply the electrodes in the very same place both as a result of we’re human. However should you change the place, even just a little bit, the mind indicators you are monitoring might be completely different.”
The traditional EEG electrodes are inflexible, too, and may shift when somebody strikes their head, even barely, which might compromise the information uniformity.
To deal with these limitations, the analysis workforce designed a small monitoring system that appears like a strand of hair and is comprised of 3D-printed hydrogel materials. One finish is the electrode. It appears to be like like a small dot and captures the mind’s electrical indicators from the scalp. There is a lengthy, skinny wire-like element that extends from the electrode, which connects to the monitoring system.
The system additionally makes use of a 3D-printable bioadhesive ink that permits the electrode to stay immediately onto the scalp with out the necessity for any gloopy gels or different pores and skin preparation. This minimizes the hole between the electrode and scalp, bettering the sign high quality. The light-weight, versatile and stretchable nature of the system additionally signifies that the system stays put — even when combing hair and donning and eradicating a baseball cap — and might be worn for longer durations of time, making it appropriate for continual monitoring.
The workforce discovered that the brand new system carried out comparably to gold electrodes, the present normal electrodes used for EEG. Nevertheless, the hairlike electrode maintained higher contact between the electrode and pores and skin and carried out reliably for over 24 hours of steady put on with none degradation in sign high quality. As a result of the electrodes do not should be eliminated and changed like conventional EEG monitoring methods, they remove the danger of inconsistent knowledge, even throughout completely different monitoring classes.
“You do not have to fret if the place of the electrode has modified or if the impedance has modified as a result of the electrodes have not moved,” Zhou mentioned.
Not like the normal steel electrodes, the brand new electrodes mimic human hair and are inconspicuous on the pinnacle. Because the system is 3D-printed, Zhou defined that they will print the electrode in numerous colours to match an individual’s hair, too.
“This makes it discreet, and folks could also be extra snug sporting this, particularly in the event that they require steady EEG monitoring and must put on the electrodes for an prolonged time frame,” Zhou mentioned.
Presently, the EEG continues to be wired; sufferers must be related to a machine whereas their mind exercise is recorded. Sooner or later, the researchers hope to make the system wi-fi so that individuals can transfer round extra freely throughout recording classes.
Different Penn State authors on the paper embrace lead authors Salahuddin Ahmed and Marzia Momin, each doctoral college students within the Division of Engineering Science and Mechanics. Jiashu Ren, doctoral scholar within the Division of Engineering Science and Mechanics; Hyunjin Lee, doctoral scholar within the Division of Biomedical Engineering; Li-Pang Huang, analysis assistant; and Basma AlMahmood, undergraduate scholar within the Division of Physics additionally contributed to the paper.
Different authors embrace Chi-Ching Kuo, Archana Pandiyan and Loganathan Veeramuthu from the Division of Molecular Science and Engineering, Nationwide Taipei College of Know-how.
Funding from the Nationwide Institutes of Well being; Oak Ridge Related Universities; the Nationwide Taipei College of Know-how-Penn State Collaborative Seed Grant Program; and the Division of Engineering Science and Mechanics, the Supplies Analysis Institute and the Huck Institutes of Life Sciences at Penn State supported this work.