Expect more powerful emotional reactions to your thoughts than usual, I think this is a major aspect of negative/positive loops. Be sure to seek out positive environments (both physical and psychical), even if your thoughts start to turn on you it is usually possible to get them back on track by a change in setting, music, company, activity, etc etc. They key is gentle, indirect guidance rather than brute force.
Expect to find associations where there were none to be found previously, which can lead you to think about things in new ways, and find novel conclusions to diverse lines of inquiry. Especially interesting is a sense of interconnectedness of all things (in a way distinct from the indeterminate oneness of dissociatives), and a propensity to find the beauty and majesty inherent in all things, or perhaps the all-thing (i.e. the great cosmic oneness, Indra's net, God in a pantheistic sense).