I'm studying structure-function relationships in neurons and mainly focusing on correlations between dendritic length and excitability. My question is:
When searching for correlations, which multiple comparison correction should I use to classify which of the correlations I find are significant?
I have measured dendrite length (apical and basal) which provided me with 3 values: apical dendrite length, basal dendrite length and total dendrite length. I've also measured 5 different electrophysiological paramaters within the same cells. My research question is: Are the electrophysiological parameters related (correlated) with the dendritic length? This yields 3×5 comparisons (3 length parameters with 5 electrophysiological). I have found some significant correlations, as expected. Now I want to find out whether the significance of these correlations must be corrected, and if so, which method I must use. Bonferoni correction seems a little too conservative, because correlations between structure and function of a neuron seems logical, and it has already been established that they exist.