Dr. Hasan Al-Nashash (AUS) and Dr. Hasan Mir (AUS)
Motivation: Extreme high or low cognitive workload in active applications which require attention and vigilance (like airport security, surveillance and driving) can lead to reduction in cognitive efficiency.
Goal: If vigilance level is measured accurately, it is possible to achieve cognitive enhancement and reach optimum cognitive efficiency by engaging the subject with challenging stimuli or task sharing.
Method and Results: Eye saccade amplitude, saccade velocity, blink frequency and dynamic of F-theta EEG waves exhibit significant changes due to challenge integration. (p<0.05).
Dr. Hasan Mir (AUS) and Dr. Hasan Al-Nashash (AUS)
Motivation: Imaging cortical sources of activity is potentially useful in assisting treatment of patients with conditions such as epilepsy. Imaging is usually performed using CT/MRI which are costly. EEG provides a cost-effective alternative. However, EEG has low spatial resolution.
Goal: To develop array signal processing techniques that will improve the spatial resolution of EEG. This will allow for an effective and low-cost solution for monitoring cortical activity.
Methods: An iterative non-parametric imaging algorithm is used in conjunction with a transfer function based calibration algorithm to account for uncertainties in the response of the EEG system
Results: EEG signals collected from epileptic human subjects in a clinical environment were processed. Initial results show that the developed signal processing techniques demonstrate good levels of sensitivity and specificity, and may potentially provide a useful complement to existing clinical assessment methods.
Dr. Hasan Mir (AUS) and Dr. Hasan Al-Nashash (AUS)
Motivation: There is a need to develop methods for evaluating the level of SCI. Such methods are important not only for evaluating the effectiveness of therapeutic mechanisms, but also in providing timely surgical intervention.
Goal: To use physiological signals to develop a non-subjective and quantitative assessment of the severity of SCI
Methods: The similarity between a somtaosensory evoked potential (SEP) signal from a healthy spinal pathway (which in the event of thoracic SCI can be obtained by forelimb stimulation) and a SEP signal from an injured spinal pathway (which can be obtained by hindlimb stimulation) can be used as an objective measure of the severity of SCI, thus providing a complementary measure to qualitative behavioral based assessments
Results: The developed SCI quantification methods were applied to SEP signals on rodents that were subjected to spinal cord transection. The results exhibit a high degree of correlation with existing subjective SCI assessment methods. Moreover, the results provide a foundation for studying phenomena such as neural plasticity.
Dr. Hasan Al-Nashash (AUS) and Dr. Hasan Mir (AUS)
Motivation: X-rays are commonly used to monitor bone healing. However, regular use of X-rays is dangerous since it produces ionizing radiation. Ultrasound is an alternative low-cost imaging modality that does not produce ionizing radiation
Goal: To develop a technique that will allow for quantitative measure for the assessment and monitoring of the bone healing process using ultrasound images.
Methods: The relationship between the B-Mode ultrasound image intensity and the acoustic impedance was studied. A quantitative measure of bone healing was developed that exploits an information theoretic criterion utilizing the intensity histogram of the bone and callus regions obtained from the ultrasound image.
Results: The developed method was applied to ultrasound images obtained from standard non-biological materials as well as a pilot experimental study on human subjects. The obtained results demonstrate that the proposed method is capable of monitoring and quantifying the degree of bone healing process. Moreover, the results provide a foundation for studying other properties such as bone density.
Dr. Amani Al-Othman (AUS), Dr. Mohammad Al-Sayah (AUS), Dr. Hasan Al-Nashash (AUS)
Motivation: Implantable electrodes represent a major component of the current solutions proposed to help restoring motor functions after peripheral nerve injuries. Implanted electrodes function by detecting neural signals and/or stimulating muscle tissues to bridge the proximal end of the injured peripheral nerve with the respective muscle. The major challenges of designing implantable electrodes include biocompatibility, corrosion, mismatch between stiff electrodes and neurons, recording reliability, signal to noise ratio , cost ( as platinum and Iridium are used).
Goal: develop a novel implantable electrode architecture to reduce electrode-tissue motion artifacts.
Methods: Biocompatible conductive polymers are investigated to fabricate bio-electrodes.
The synthesized bio-electrodes are characterized by their electrical impedance and mechanical properties.
Results: The developed implantable electrodes should be capable of stimulating the muscle tissues and or/detecting neural signals using functional, less expensive materials, and durable materials.
