I would have to disagree that Melatonin, Serotonin, and DMT are the gateways to accessing other dimensions. While these neurotransmitters may assist in the actual travel the gateway is thought, pure. We are transmitters of our higher self, which in turn is transmitting the universal stream, not the other way around. It is our higher self which is the actual gateway, the body has to be prepared to maintain the energy that is focused through thought that creates the gateway then powered, as a boat with gas, by the neurotransmitters which are under a controlled release by the pineal gland.