[BIC-announce] FW: Dr. Andrew Ioannides lecture on Aug. 1, 2007 from 4:00 p.m. to 5:30 p.m. Magnetoencephalography (MEG): Challenged by and Challenging Neuroscience

[Jennifer Chew, Ms.]

***LECTURE***
 
DATE:  Wednesday, August 1, 2007 
LOCATION:  De Grandpré Communications Centre - BTRC 3B
TIME:  4:00 P.M. to 5:30 P.M. 

SPEAKER: Dr. Andreas A. Ioannides
	   Lab for Human Brain Dynamics
	   Brain Science Institute (BSI), RIKEN, 2-1 Hirosawa
	   Wako-shi, Saitama 3510198
	  Japan  
TITLE:  Magnetoencephalography (MEG):  Challenged by and Challenging Neuroscience 
 
Magnetoencephalography (MEG) has always been associated with excellent temporal resolution.  It is now becoming apparent that tomographic analysis of MEG signals can provide accurate localization, at least for places a few centimeters away from the center of the head. It is therefore becoming possible to explore brain function by accurately mapping activity over the entire cortical mantle and probing interactions between areas across timescales ranging from milliseconds to minutes in the same run, for example when a piece of music is played.  This capability is however difficult to handle because it is difficult to prove the veracity of the images in the new spatiotemporal domain that the MEG unveils; there is simply no gold standard to compare. This challenge for MEG has been met by two kinds of meaningful tests of accuracy. First, by using other techniques, for example, the responses were analyzed using tomographic analysis of the average data and the results were compared with responses to identical stimuli on the same subjects using fMRI. The loci of activation within V1 for MEG and fMRI agreed to within a few millimeters, which was as good as the coregistration of the data would allow.  Alternatively detailed analysis of the spatiotemporal evolution of activity was compared for tasks producing well defined activations thoroughly documented in animal experiments , e.g. for simple visual stimuli, sleep or eye movements. The challenge for MEG now is how to package the information that springs forth from the data analysis into chunks that are meaningful for neuroscience and/or clinically useful. The challenge for Neuroscience is to formulate problems to chart the new spatiotemporal terrain that now becomes accessible from millimeter to many centimeters in space and from millisecond to hours in time.



Jennifer (as requested by Dr. Alan Evans) 

Jennifer Chew

McConnell Brain Imaging Centre

MNI - WB317

3801 University Street

Montreal, Qc  H3A 2B4

Telephone:  514-398-8554

Fax:  514-398-2975