[Eeglablist] Minimum number of Trials for ERSP Analysis

[Gozde BAYER]

Dear EEGLAB List,

I have been trying to design an experiment with many different types of 
visual stimuli (e.g. 8 different video types) from which I plan to get 
some specific frequency responses, for example getting band power of 
beta frequency within a specific time window. I know that I need several 
repetition of each video type so that there will be many trials to get 
an ERSP analysis,say for each subject...But since I have already 8 video 
types and if I repeat each video 10 times for example, it will end up 
with 80 videos in total. From my previous experience, subjects 
undergoing long visual stimuli may get bored and lose attention very 
easily.
My question is: what should be the "minumum number of trials" to get a 
reasonable/valid ERSP analysis ? I think the higher the better but in my 
case this means lots of video stimulations which becomes impractical..If 
the repetition of each video is 12 then 8x12=96 videos in total. Then 
should I rely on such trial numbers (n=10,11,12..)  while calculating 
ERSP ?
So far, I have been unable to find a paper on this issue..

I would appreciate any help,
Thank you vey much.

Gözde BAYER