Your gonna have to try and describe it with as many words as you can.Without a picture,your description is all we have to go off of.There are 100's of different "brain" corals,do a search to see if you can find the scientific name for yours.My guess,is your describing the skeleton features which are not usually visible in a healthy coral
I am unable to give you a photo. The protusions are the same color as the rest of the coral except that they protude like little pointed volcanoes that is the best way to describe it Hope this can help a little. What are good sources to determine the type of brain coral that it is?