Naslov
MEG – Neurodynamic insight into cortical processing pathways

Autori
Supek, Selma

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book of Abstracts / Bezerianos, Anastasios - Patras, 2010

Skup
5th International Summer School on Emerging Technologies in Biomedicine “High Throughput Communication between Brain and Machines”

Mjesto i datum
Patras, Grčka, 26.09.2010. - 01.10.2010

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
magnetoencephalography (MEG); cortical neurodynamics; perception; cognition

Sažetak
Magnetoencephalography (MEG) represents one of the major functional brain imaging techniques capable to provide unique insight into the basic mechanisms of sensory and cognitive processes of the human brain and characterization of pathologies that impair its normal function [1]. Functional cortical pathways and neurodynamics, however, are challenging and largely unknown despite significant advances in the functional and structural imaging of the human brain. Such information is not readily available even with the invasive approaches since they are typically performed on epileptic patients providing pathology related distortions. The relevance of the extraction of the neuronal activation pattern from the extracranially collected data comes from evidences that dysfunction and age related changes are often related to the interaction pathways. MEG represents a direct and real-time measure of neuronal activity and offers monitoring of the spontaneous and evoked brain responses with a millisecond resolution parallel only to the electroencephalography (EEG). Spatio-temporal source localization approaches relay on source modeling and inverse problem estimation strategies to track cortical pathways both in space and time. MEG offers the possibility of identifying the underlying neuronal substrate and tracking when, where, and how the activity changes over time without knowledge of a detailed conductive geometry profile. Neuromagnetic source location and dynamics accuracy, however, is model and inverse procedure dependent. The results of experimental and numerical simulation studies will be presented on the spatio-temporal source discrimination as well as location and time course estimation accuracy of the activated cortical sources [2, 4]. Since functional neuroanatomy differs between individuals we will provide empirical and simulation evidences in favor of a within subject analysis [5] in particular in the light of a lifetime neuroplasticity of the brain both in health and disease. Neuromagnetic studies on the human visual processing have demonstrated, among others, multiple retinotopically organized visual areas [6], stimulus and task specific visual pathways [7, 8], and detailed insight into individual functional neuroanatomy [5]. The study of neuronal correlates of visual and auditory perception has demonstrated a distributed network of cortical activations whose dynamics can be modulated by physical characteristics of the stimuli, task relevance, age, and pathology [5, 7, 8, 9]. Since our first MEG demonstration of the primary visual cortex reactivation during a spatial visual attention task via a feedback mechanism [10] such a top-down regulation has been demonstrated in a range of cognitive tasks and has been recently proposed to play an important role in a search for neural correlate of consciousness. References: 1. Aine, C.J.: Highlights of 40 years of SQUID-based brain research and clinical applications. In. S. Supek and A. Susac (Eds.): Advances in Biomagnetism – BIOMAG2010, IFMBE Proceedings 28, pp. 9-34, 2010. 2. Supek, S., Aine, C.J.: Simulation studies of multiple dipole neuromagnetic source localization: Model order and limits of source resolution. IEEE Transactions on Biomedical Engineering, 40:529-540, 1993. 3. Supek, S., Aine, C.: Spatio-temporal modeling of neuromagnetic data: I. Multi-source location vs timecourse estimation accuracy, Human Brain Mapping, 5: 139-153, 1997.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA