[Eeglablist] ICA Problem

[Habib Paracha]

Hi, I am performing fast ICA on a 14 Channel EEG data. Reducing the dimension of data from 14 to 5 components. When I perform the ICA I get a different result every time I run it. I am using the FASTICA toolbox available for matlab. The Question is how will I be able to figure out which is the most suitable component of all the extracted ICs. I am trying to extract the P300 response from the data. I get the P300 data component randomly in the 1st, 2nd, 3rd or 4th Component. I have to visually figure out which is the best extracted IC and then rest of the code.Sometimes I even get the P300 signal but it is inverted(instead of the positive peak ICA outputs a negative peak data). Someone kindy tell me a technique to automatically detect the best component and run the rest of the code using this component.Also a way to cater the wrong results of ICA.  Regards, Habib Paracha 		 	   		  
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