Developed by Vladislav Staroselskiy

CFMI Members


Andrei Medvedev, Ph.D.

Position:

Assistant Professor

School:

M.Sc. -- Moscow Institute of Physics & Technology, 1979, Biophysics
Ph.D. -- Russian Academy of Sciences, Moscow, 1989, Neurophysiology

Bio:

EDUCATION AND PROFESSIONAL EXPERIENCE:
Dr. Medvedev is a neurophysiologist and computational neuroscientist. After completing his graduate training in Physiology and Neural Networks at the Dept. of Biophysics, Moscow Institute of Physics and Technology, he worked at the Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, where he received his Ph.D. degree in 1989 followed by a position as a Senior Research Officer. In 1989-92, he was a Senior Staff Scientist at the Italian-Russian Joint Venture �Neuromachines�. From 1993-2001, he worked at the Epilepsy Laboratory at Flinders University Medical Center, Adelaide, Australia, where he was a Chief co-Investigator in several projects funded by the National Health and Medical Research Council. In April of 2001, he joined the Laboratory for Audiovocal Communication and Cognition, Dept. of Physiology and Biophysics, Georgetown University Medical Center, and in December of 2003 he joined the Center for Functional and Molecular Imaging.

RESEARCH INTERESTS:
Dr. Medvedev�s expertise includes systems electrophysiology, signal analysis and neural network modeling. His research interests focus on neural mechanisms of cognitive processes in norm and neurological pathology. From 1980-2001, he was actively involved in basic research of epilepsy using rat models of chronic and acute epileptogenesis. This research revealed an important role of abnormally increased gamma-band (30-100 Hz) activity as a predisposing factor in the epileptic process (Medvedev 2001, 2002). His current research at the CFMI combines a new technology of noninvasive near-infrared (NIR) optical functional imaging of the brain with a more traditional electrophysiological analysis of on-going and event-related electrical activity (EEG, ERP, evoked and induced gamma-band oscillations). Hemodynamic (as measured by NIR) and electrical responses of the brain are studied to analyze spatiotemporal organization and hemispheric lateralization of normal cognitive functions, such as speech and decision-making, as well as pathophysiological mechanisms of neurological diseases (autism and epilepsy). Combination of different technologies to analyze dynamic processes of the brain will provide new insights into the integrative mechanisms of cognitive functions and how those processes and mechanisms are disturbed in neurological diseases.


Publications:

Medvedev AV and Sidorov BM (1992) Analysis of precise movement optimisation in cats. In: Lecture Notes on the ICB seminar "Medical biomechanics of spine", Warsaw, pp 118-125==break==Medvedev A (1995) Spike and wave discharge of primary generalised epilepsy: excess excitability or impaired inhibition? In: Proc. of the Sixth Australian Conference on Neural Networks, Sydney, pp 69-72==break==Willoughby JO, Mackenzie L, Medvedev A and Hiscock JJ (1995) Distribution of Fos-positive neurons in cortical and subcortical structures after picrotoxin-induced convulsions varies with seizure type. Brain Res 683: 73-87==break==Willoughby JO and Medvedev A (1996) Opioid receptor activation resets the hypothalamic clock generating growth hormone secretary bursts in the rat. J Endocrinol 148: 149-155==break==Medvedev A, Mackenzie L, Hiscock JJ and Willoughby JO (1996) Frontal cortex leads other brain structures in generalised spike-and-wave spindles and seizure spikes induced by picrotoxin. Electroenceph clin Neurophysiol 98: 157-166==break==Vickers D, Vincent N and Medvedev A (1996) The geometric structure, construction and interpretation of path-following (trail-making) tests. J Clin Psychol 52: 651-61==break==Willoughby JO, Mackenzie L, Medvedev A and Hiscock JJ (1997) Fos induction following systemic kainic acid: early expression in hippocampus and later widespread expression correlated with seizure. Neuroscience, 77: 379-392==break==Willoughby JO, Hiscock JJ, Medvedev A, Mackenzie L (1999) Generalised convulsive epilepsy: possible mechanisms. J Clin Neurosci 6: 189-194==break==Medvedev A and Willoughby JO (1999) Autoregressive modeling of the EEG in systemic kainic acid-induced epileptogenesis. Int J Neurosci 97: 149-167==break==Medvedev A, Mackenzie L, Hiscock JJ and Willoughby JO (2000) Kainic acid induces distinct types of epileptiform discharge with differential involvement of hippocampus and neocortex. Brain Res Bull 52: 89-98==break==Vickers D, Butavicius M, Lee MD and Medvedev A (2001) Human performance on visually presented Travelling Salesman problems. Psychol Res 65: 34-45==break==Hiscock JJ, Mackenzie L, Medvedev A and Willoughby JO (2001) Kainic acid and seizure-induced Fos in subtypes of cerebrocortical neurons. J Neurosci Res 66:1094-1100==break==Medvedev AV (2001) Temporal binding at high (gamma) frequencies in the brain: paving the way to epilepsy? Australas Phys Eng Sci Med 24: 37-48==break==Mackenzie L, Medvedev A, Hiscock JJ, Pope KJ and Willoughby JO (2002) Picrotoxin-induced generalized convulsive seizure in rat: changes in regional distribution and frequency of the power of EEG rhythms. Clin Neurophysiol 113: 586-596==break==Medvedev AV (2002) Epileptiform spikes desynchronize and diminish fast (gamma) activity of the brain. An 'anti-binding' mechanism? Brain Res Bull 58: 115-128==break==Medvedev AV, Chiao, F and Kanwal JS (2002) Modeling complex sound perception: grouping harmonics with combination-sensitive neurons. Biol Cybern 86: 497-505==break==Willoughby JO, Mackenzie L, Broberg M, Thoren AE, Medvedev A, Sims NR and Nilsson M. (2003) Fluorocitrate-mediated astroglial dysfunction causes seizures. J Neurosci Res 74: 160-166==break==Kanwal JS, Medvedev AV and Micheyl C (2003) Neurodynamics for auditory stream segregation: tracking sounds in the mustached bat's natural environment. Network: Comput. Neural Syst 14: 413-435==break==Willoughby JO, Fitzgibbon SP, Pope KJ, Mackenzie L, Medvedev AV, Clark CR, Davey MP, Wilcox RA (2003) Persistent abnormality detected in the non-ictal electroencephalogram in primary generalised epilepsy. J Neurol Neurosurg Psychiatry 74: 51-55==break==Medvedev AV and Kanwal JS. (2004) Local field potentials and spiking activity in the primary auditory cortex in response to social calls. J Neurophysiol 92: 52-65==break==