I have been thinking along the lines of too much LSD, but that is only conjecture. He was interested in brain function and abnormal brain function, so i am assuming he had an interest in LSD. It is the substance of choice for wacked out, totally altered state of mind. in my opionion LSD is not 'bad' in and of itself, but it is totally dangerous in certain situations, especially if you are tripping a lot by yourself. solitary tripping can be the epitome of a paranoid, delusional state if you do not feel totally comfortable with your surroundings. High anxiety would also lead to bad trips, in my opinion. Abusing LSD while alone (tripping by yourself, indoors) can be a bewildering, dark experience. When using LSD with really close friends who you know love and care about you can be a wonderful, positive event. And outdoor tripping during the daytime is almost always a light, fluffy trip.
My opinion about the ecstasy is NO WAY a person who is high on real MDMA could commit such a brutal crime, unless he was suffering from the after effects of MDMA abuse. It drains the serotonin and low serotonin is linked to violence and suicide.