What are the neurological / psychological benefits of masturbation?

Same as intercourse: Sexual release is a positive neuro and psycho benefit. In the right frame of mind, in the right mood, timing, setting & done in the proper way, masturbation could be just a beneficial and satisfying as penile/vaginal intercourse. Whether one is greater than the other would be speculative and personal. Many engage in masturbatory sessions for relief of stress, tension and anxiety & simple pleasure.

It feels good: That should be enough.