Shirley Coyle

On the suitability of near-infrared (NIR) systems for next-generation brain–computer interfaces

A brain-computer interface (BCI) gives those suffering from neuromuscular impairments a means to interact and communicate with their surrounding environment. A BCI translates physiological signals, typically electrical, detected from the brain to control an output device. A significant problem with current BCIs is the lengthy training periods involved for proficient usage, which can often lead to frustration and anxiety on the part of the user. Ultimately this can lead to abandonment of the device. The primary reason for this is that relatively indirect measures of cognitive function, as can be gleaned from the electroencephalogram (EEG), are harnessed. A more suitable and usable interface would need to measure cognitive function more directly. In order to do this, new measurement modalities, signal acquisition and processing, and translation algorithms need to be addressed. In this paper, we propose a novel approach, using non-invasive near-infrared imaging technology to develop a user-friendly optical BCI. As an alternative to the traditional EEG-based devices, we have used practical non-invasive optical techniques to detect characteristic haemodynamic responses due to motor imagery and consequently created an accessible BCI that is simple to attach and requires little user training.

Wireless Sensor Networks and Chemo-/Biosensing

3.4.5. Example 5: Volcanic Activity 658 3.4.6. Example 6: Soil Moisture 659 3.5. Discussion and Conclusions 659 4. Body Sensor Networks 661 4.1. Wearable Sensors 661 4.2. Functionalized Fabrics 662 4.2.1. Metal Fibers 662 4.2.2. Conductive Inks 662 4.2.3. Inherently Conducting Polymers 662 4.2.4. Optical Fibers 662 4.2.5. Coating with Nanoparticles 662 4.2.6. Integrated Components 663 4.2.7. Wearable Actuators 663 4.2.8. Interconnects and Infrastructure 664 4.3. Applications of Wearable Sensors 665 4.4. Wearable Chemosensing 667 4.5. Applications in Personalized (p)Health 668 4.6. Conclusions 670 5. Materials SciencesThe Future 670 5.1. Microfluidics and Lab-on-a-Chip Devices 670 5.2. Controlling Liquid Movement in Surfaces and on Channels 671

BIOTEX—Biosensing Textiles for Personalised Healthcare Management

Textile-based sensors offer an unobtrusive method of continually monitoring physiological parameters during daily activities. Chemical analysis of body fluids, noninvasively, is a novel and exciting area of personalized wearable healthcare systems. BIOTEX was an EU-funded project that aimed to develop textile sensors to measure physiological parameters and the chemical composition of body fluids, with a particular interest in sweat. A wearable sensing system has been developed that integrates a textile-based fluid handling system for sample collection and transport with a number of sensors including sodium, conductivity, and pH sensors. Sensors for sweat rate, ECG, respiration, and blood oxygenation were also developed. For the first time, it has been possible to monitor a number of physiological parameters together with sweat composition in real time. This has been carried out via a network of wearable sensors distributed around the body of a subject user. This has huge implications for the field of sports and human performance and opens a whole new field of research in the clinical setting.

Textile-Based Wearable Sensors for Assisting Sports Performance

There is a need for wearable sensors to assess physiological signals and body kinematics during exercise. Such sensors need to be straightforward to use, and ideally the complete system integrated fully within a garment. This would allow wearers to monitor their progress as they undergo an exercise training programme without the need to attach external devices. This takes physiological monitoring into a more natural setting. By developing textile sensors the intelligence is integrated into a sports garment in an innocuous manner. A number of textile based sensors are presented here that have been integrated into garments for various sports applications.

Physiological noise in near-infrared spectroscopy: implications for optical brain computer interfacing

Near-infrared spectroscopy is a non-invasive optical method used to detect functional activation of the cerebral cortex. Cognitive, visual, auditory and motor tasks are among the functions that have been investigated by this technique in the context of optical brain computer interfacing. In order to determine whether the optical response is due to a stimulus, it is essential to identify and reduce the effects of physiological noise. This paper characterizes noise typically present in optical responses and reports signal processing approaches used to overcome such noise.

Breathing Feedback System with Wearable Textile Sensors

Breathing exercises form an essential part of the treatment for respiratory illnesses such as cystic fibrosis. Ideally these exercises should be performed on a daily basis. This paper presents an interactive system using a wearable textile sensor to monitor breathing patterns. A graphical user interface provides visual real-time feedback to patients. The aim of the system is to encourage the correct performance of prescribed breathing exercises by monitoring the rate and the depth of breathing. The system is straight forward to use, low-cost and can be installed easily within a clinical setting or in the home. Monitoring the user with a wearable sensor gives real-time feedback to the user as they perform the exercise, allowing them to perform the exercises independently. There is also potential for remote monitoring where the user’s overall performance over time can be assessed by a clinician.

Textile sensors to measure sweat pH and sweat-rate during exercise

Sweat analysis can provide a valuable insight into a persons well-being. Here we present wearable textile-based sensors that can provide real-time information regarding sweat activity. A pH sensitive dye incorporated into a fabric fluidic system is used to determine sweat pH. To detect the onset of sweat activity a sweat rate sensor is incorporated into a textile substrate. The sensors are integrated into a waistband and controlled by a central unit with wireless connectivity. The use of such sensors for sweat analysis may provide valuable physiological information for applications in sports performance and also in healthcare.

Distributed Monte Carlo simulation of light transportation in tissue

A distributed Monte Carlo simulation which models the propagation of light through tissue has been developed. It allows for improved calibration of medical imaging devices for investigating tissue oxygenation in the white matter of the cerebral cortex. The application can distribute the simulation over an unbounded number of processors in parallel. We have found that this application is highly parallelisable resulting in up to 91% efficiency at 60 processors running on a homogeneous Java distributed system. A distributed system with 150 heterogeneous processors was used to simulate the paths of photons in a brain tissue model. We found that the source illumination footprint has an effect on the distribution of photons in the head and that lasers do produce a small beam in a highly scattering medium. This application will help researchers to improve the accuracy of their experiments

Wearable technology for bio-chemical analysis of body fluids during exercise

This paper details the development of a textile based fluid handling system with integrated wireless biochemical sensors. Such research represents a new advancement in the area of wearable technologies. The system contains pH, sodium and conductivity sensors. It has been demonstrated during on-body trials that the pH sensor has close agreement with measurements obtained using a reference pH probe. Initial investigations into the sodium and conductivity sensors have shown their suitability for integration into the wearable system. It is thought that applications exist in personal health and sports performance and training.

Bio-sensing textiles - Wearable Chemical Biosensors for Health Monitoring

In recent years much progress has been made in the integration of physical transducers into clothing e.g. breathing rate, heart rate and temperature [1]. The integration of chemical sensing into textiles adds a new dimension to the field of smart clothing. Wearable chemical sensors may be used to provide valuable information about the wearer’s health, monitoring the wearer during their daily routine within their natural environment. In addition to physiological measurements chemical sensors may also be used to monitor the wearer’s surrounding environment, identifying safety concerns and detecting threats. Whether the clothes are looking into the wearer’s personal health status or looking out into the surroundings, chemical sensing calls for a novel approach to sensor and textile integration. In contrast to physical sensors, chemical sensors and biosensors depend on selective reactions happening at an active surface which must be directly exposed to a sample. Therefore issues of fluid handling, calibration and safety must be considered. This paper discusses the constraints in integrating chemical sensors into a textile substrate. Methods of fluid control using inherently conducting polymers (ICPs) are discussed and a pH textile sensor is presented. This sensor uses colorimetric techniques using LEDs controlled by a wireless platform. Some of the potential applications of wearable chemical sensors are discussed.