[igraph] Functional EEG network analyses in R

[Anaya, Berenice]

Hello, 
I am new to the igraph package, and I am trying to analyze EEG coherence data. 
These data is based on the phase relation between electrode signals, and I 
currently have adjacency matrices for every participant in my sample, which are 
128 x 127 matrices of correlations between all the electrodes. I understand the 
general language of igraph once the graph object itself is created, but I am 
having some trouble setting up so I can make the object. I am writing to ask 
for help on:
1) How do I read in all my matrices (1 per participant, total of 177 
participants) and create a graph object? 
2) Would the graph object be based on the average of all these matrices? 
3) How would I go about including the map of where the electrodes go on the 
scalp?

Thank you, Berenice