Control in Bioengineering:
Applications to the Nervous System
DIRECT IMPACT
Learning about the technicalities of various control systems in neuroscience and neuroengineering, it is easy to forget that the work of bioengineers have a direct impact on society. The applications explained in this website have improved the quality of life of many people. Here are some of their stories...
Functional Electrical Stimulation
Lida – life after stroke
More than 14 years after her stroke, Lida can now walk without pain thanks to ActiGait, the implantable Functional Electrical Stimulation (FES) device.
“At the age of 33 in January 1998 and a single mother of two young children, I suffered a devastating stroke. Following a five month hospital stay and after extensive physiotherapy I returned home but struggled to remain independent and found it difficult to get used to my new life. I was forced to leave my job as a property lawyer and my parents.’
‘Following extensive research into new technologies, in December 2011 at the age of 47, I was invited by my consultant at BMI The Blackheath Hospital to trial a new implantable ActiGait FES® implant device. I was so excited – it was the answer I had been waiting for.’
‘Before ActiGait, I had to wear baggy clothes and wasn’t able to wear dresses or skirts due to the embarrassment of visible wires and electrodes on my leg from my old drop foot solution, which made me feel unfeminine.’
‘My biggest wish is to help other sufferers to the stage I’m now at, living an independent life. Now I have the confidence to go out, dress the way I want and I feel normal again. For the first time in years I can look forward to the summer and wear dresses and sandals again.’ [1]
Exoskeletons
In the present, exoskeletons are being employed for a wide variety of practical applications, and this list will likely keep on expanding in the few years.This covers not only military uses, but also civil, daily life applications.
Many of exoskeletons today are designed for military purposes. The primary focus of many military-oriented exoskeletons is to enable soldiers carry heavy loads while retaining agility.[2] This is especially useful during emergency missions such as disaster relief, where personnel are required to carry an array of equipments while traversing harsh terrain.
There are also a range of exoskeletons developed for non-military purposes. A large percentage of them are designed for medical uses, particularly assisting people with disability and aiding rehabilitation of injured patients.[3]
Below are several products in use today:
Brain Computer Interface
Stephen Hawking, pictured right, has trialled brain computer interfaces in the past to assist him in delivering lectures and speaking through speech synthesis. However, the inconsistency of this system as opposed to the system he currently uses, has made him prefer to use the latter. Intel® has specially designed for him a device which he has control through movements of his cheek. An infrared switch on his glasses detects his cheek movements and through this, he is able to control the cursor on his tablet screen mounted on his wheelchair. On his personal website, he writes that engineers at Intel® are developing a new interface system for him and that he is interested to see the results of these.[4]
BCI offers great promise in the future as a tool for paralyzed or disabled people, or people suffering from late-stage ALS. BCI also is proposed to be used recreationally in video gaming and virtual reality. However, there are challenges to be overcome before we can see BCI being used on a larger scale. These are low reliability, meaning that current BCI systems simply aren't reliable enough to be used on a daily basis. Low reliability results from poor EEG signal production and also poor processing of that signal.[5]
Users need to be trained to control the BCI which is a hard task for paralyzed or disabled patients. Users are trained in producing the correct EEG signals and also in producing strong signals. [6] Research in BCI continues and it is hopeful through control, that we may see BCI on a larger scale in the future.
Figure 1: Stephen Hawking and his assistive technology produced by Intel.
Cochlear Implants
Natalie’s parents were devastated when they found out that their otherwise healthy daughter had profound hearing loss.[7] For children who are born deaf, early treatment with cochlear implants is recommended as it enables them to develop their language skills at a similar pace to that of children with normal hearing.
“As a parent of a cochlear implant recipient, you wait so long to be called “Mum” or “Dad’ and when they call you that for the first time, it’s just wonderful! … With bilateral implants, Natalie can pick up more accurate sounds from different directions. After getting bilateral implants, we’ve noticed that Natalie’s pronunciation is very clear. She can locate the direction of sound better, it’s easier for her to communicate with the family, and she looks to be more confident which has improved her social skills a lot.
She’s talking just like a normal child. Natalie’s first word was “mama” which she said 3 months after switch on. After receiving her cochlear implant at 12 months old, Natalie picked up words very quickly. By the time she was two, she was on par with normal hearing children the same age. By the age of two, she could recognise and read the alphabet. By the age of three years she was learning three languages: Mandarin, English and Bahasa Malay.” (as told by Natalie's Dad)
Figure 2: Natalie with her cochlear implants [7]
References
1. Ottobock.co.uk, (2016). Lida - Life after stroke — Ottobock UK. [online] Available at: http://www.ottobock.co.uk/neurorehabilitation/success- stories/ [Accessed 7 Feb. 2016].
2. Zoss, A., Kazeeroni H. and Chu, A. 2005. On the mechanical design of the Berkeley Lower Extremity Exoskeleton (BLEEX), [online] 2005 IEEE/RSJ International Conference on Intelligent Robots and Systems. Edmonton, AB, Canada, 2-6 August 2005.
3. Cain, S.M., Gordon, K.E. and Ferris, D.P. 2007. Locomotor adaptation to a powered ankle-foot orthosis depends on control method. [online] Journal of Neuroengineering and Rehabilitation, 4:48.5. Ferris, D.P., Gordon, K.E., Sawicki, G.S. and Peethambaran, A. 2006. An improved powered ankle–foot orthosis using proportional myoelectric control. [online] Gait & Posture, 43(4), 425-428.
3. Figure 1: https://commons.wikimedia.org/wiki/File:Stephen_Hawking_in_Cambridge_cropped.jpg
4. http://www.hawking.org.uk/the-computer.html
5. Brumberg, Jonathan S., et al. "Brain–computer interfaces for speech communication." Speech communication, 52.4 (2010): 367-379.
6. Lotte, Fabien, and Camille Jeunet. "Towards improved bci based on human learning principles." Brain-Computer Interface (BCI), 2015 3rd International Winter Conference on. IEEE, 2015.
7. Cochlear.com, (2016). Natalie's Story | Children Born Deaf | Cochlear UK. [online] Available at: http://www.cochlear.com/wps/wcm/connect/uk/home/understand/my-child-was-born-deaf/hearing-stories-from-cochlear-implant-recipients/natalies-story [Accessed 8 Feb. 2016].