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Ahmet Omurtag

Lecturer/Senior Lecturer

School of Science & Technology

Staff Group(s)
Engineering

Role

Dr Omurtag comprises a teaching and research role in the Engineering Department.

Career overview

Ahmet joined NTU from the University of Houston where he was Associate Professor of Biomedical Engineering. He obtained a Ph.D. in Mechanical Engineering from Columbia University and post-doctoral training in computational neuroscience at the Mount Sinai School of Medicine. Ahmet’s research has received funding from National Institutes of Health and the National Science Foundation in the United States. He was director of research and engineering at Bio-Signal Group, a private company, where he worked on all aspects of biomedical device development.

Research areas

Ahmet is an expert in the biomedical applications of electroencephalography, functional near-infrared spectroscopy (fNIRS), and signal analysis. EEG is a functional brain imaging method that is sensitive to the brain's organized synaptic activity. fNIRS, on the other hand, measures hemoglobin concentration changes in the upper layers of cortex through near-infrared light probes placed on the scalp. Ahmet takes advantage of the strengths of each modality and combines their signals.

His research in recent years has been at the forefront of practical, noninvasive multimodal functional neuroimaging. One of his aims is to create markers for predicting human performance. Such markers can provide objective measures of operators' skill levels, characteristics of the tasks they are engaged in, or the tools which they use.

Ahmet's methods include recording data from human subjects in the laboratory and the clinic, and analyzing them with state-of-the-art feature extraction and machine learning methods. Pooling complementary signals from different types of systems not only enhances the accuracy of the markers. It also allows research into neurovascular coupling, the cascade of processes by which neural activity modulates local blood flow and oxygenation. Ahmet is also exploring the clinical implications of neurovascular coupling, since it is part of the brain's local hemodynamic response to neural activity and is believed to be altered by disease.

External activity

Ahmet frequently puts his industry experience to use by collaborating with and consulting for companies in the area of biomedical devices. He has also served in federal U.S. grant review sections.

Sponsors and collaborators

Funders of Ahmet's work have included the National Institutes of Health, National Science Foundation. He collaborates with a wide network of scientists, engineers, and clinicians, including his former employer Bio-Signal Group, Inc.

Publications

Aghajani H, Garbey M and Omurtag A. Measuring Mental Workload with EEG+ fNIRS. Front. Hum. Neurosci, 2017, 11, 359

Omurtag A, Aghajani H and Keles HO. Decoding human mental states by whole-head EEG+ fNIRS during category fluency task performance. J. Neural Eng, 2017

Keles HO, Barbour RL and Omurtag A. Hemodynamic correlates of spontaneous neural activity measured by human whole-head resting state EEG+fNIRS, Neuroimage, 2016

Buccino AP, Keles AO and Omurtag A. Hybrid EEG-fNIRS Asynchronous Brain-Computer Interface for Multiple Motor Tasks. PLoS ONE, 2016, 11(1): e0146610

Zehtabchi S, Abdel Baki SG, Omurtag A, Sinert R, Chari G, Roodsari GS, Weedon J, Fenton AA, Grant AC. Impact of microEEG on clinical management and outcomes of Emergency Department patients with altered mental status: A randomized controlled trial,  Acad Emerg Med, 2014, 21:283-291

Zehtabchi S, Abdel Baki SG, Omurtag A, Sinert R, Chari G, Malhotra S., Weedon J, Fenton AA, Grant AC, Prevalence of Non-convulsive Seizure and Other Electroencephalographic Abnormalities In Emergency Department Patients With Altered Mental Status. The American Journal of Emergency Medicine, 2014, 31(11):1578-1582

Grant AC, Abdel Baki SG, Omurtag A, Sinert R, Chari G, Malhotra S, Weedon J, Fenton AA, Zehtabchi S, Diagnostic Accuracy of microEEG: A Miniature, Wireless EEG Device, Epilepsy and Behavior, 2014, 34: 81-85

Grant AC, Abdel-Baki S, Weedon J, Arnedo V, Chari G, Koziorynska E, Lushbough C, Maus D, McSween T, Mortati KA, Reznikov A, Omurtag A. EEG Interpretation Reliability and Interpreter Confidence: A Large Single Center Study, Epilepsy and Behavior, 2014, 32: 102-107

Press expertise

Has press expertise, willing to share experiences with developing portable medical devices, EEG and fNIRS.