So DHT via multiple pathways increases nervous system strength, DHT increases epinephrine levels, decreases prolactin (assuming you have enough dopamine production as well), increases GABA, may decrease serotonin and serotonin receptors. All-round this means DHT has positive effects on your chemistry and nerve cells. By reducing prolactin, and estrogen, and subsequently serotonin, and also regulating catecholamines, by this, DHT can definitely increase libido, and alleviate sexual anxiety in most individuals by increasing GABA. DHT is key to many of Testosterone's brain benefits. Keep in mind though, despite positive effects on brain chemistry, this still doesn't give an excuse to OD on aromatase inhibitors, likely, because you need a little bit of estrogen (not much at all), to promote nNOS (neuronal nitric oxide synthase) production. So DHT serves as a great compliment to a little bit of brain estradiol, and a great ratio of DHT to estrogen means optimal sex drive, stamina, charisma and general masculinity.


Let's summarize in Bullets Here.

• DHT regulates alpha and beta adrenergic receptors.
• DHT may increase alpha-1-receptor density.
• DHT may decrease glutamate activity and increases mGLU7 expression (which increases GABA release)
• DHT increases serotonin 5-HT1A receptor density by influencing A1-Adr.Receptors.
• DHT promotes serotonin 5-HT1A/1B activity and may reduce aggression in the presence of serotonin. Although this may easily be over ridden by the pro-adrenergic effects of DHT.
• DHT increases beta-endorphin release by ^ 5-HT1A receptor indirect activation.
• DHT facilitates the release of Epinephrine (adrenaline).
• DHT increases cyclic AMP.
• DHT blocks estrogen-induced prolactin release.
• DHT reduces serotonin and serotonin receptors by inhibiting estrogen influence in the Brain. (but mainly acting to oppose 5-HT2A,2C and 5-HT4 receptors)
• DHT increases Mitogen-Activated-Protein Kinase (MAPK) which leads to a variety of molecular changes and genomic changes as well as neural-changes; decreased serotonin activity in the brain and periphery. 
• DHT increases GABA and GABA-A (neurosteroid-specific) receptor expression. 
• DHT increases NMDA-receptors in the Hippocampus.
• DHT increases Ca3 (Calcium) evoked Acetylcholine Function(AcH release).
• DHT increases nervous system strength and regulates blood pressure.