The epithalamus has different regions to it, one of them being the pineal gland. This region is important for regulating or being aware of light versus dark. Melatonin is a neurotransmitter that would be released from this area. And vice versa going into the dark cycle where you probably are wanting to release melatonin,. which is going to be important for sleep. All these we will do a separate podcast in because they're so complex and require a lot of time. But we can quickly run through the main functions of the hypothalamus.