[Eeglablist] Problem with topographic map - spectrum activity outside the brain

[Mounia ZIAT-LOUAHADJ]

Hi,

I imported .eeg files (Neuroscan) without any problem and I used the channels locations .asc from Neuroscan. My problem is related with the 2d topographic map, the spectrum activity is shifted to the back, outside the brain (please see picture). Is it related to the references? I tried to reference to the mastoids but it doesn't change the map. I also tried with a small .cnt file and it is the same problem.

For information my eeg files have been pre-processed with Neuroscan (artefact rejection, baseline correction and filter).

The reason I am using the eeg files is that my .cnt files are very big and I was not able to open them because of the "out of memory" problem even by increasing matlab memory. The only solution is to switch to 64 bits system.
Thanks a lot for your answers.
Mounia
 		 	   		  
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