I'm performing retinotopy analysis but when running the command 

    selxavg3-sess

It starts, but after some lines, I get the following error:

    ERROR: design is ill-conditioned

I don't know how to proceed from here to solve the error. 

My retinotopy stimuli make 2 cycles (e.g.: rotating wedge makes 2 full cycles before quit) and each cycle takes 200 seconds to complete. TR is set to 2.5 seconds.

Please, does anyone have any advice?

Thanks in advance,

Marco
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