The middle of my head seem to be coupled to my heart (and cardiovascular system). If I feel changes in my head I feel something going on with the heart. Sexual triggers affect middle of my head and thus affects heart.
I once ate L-Dopa (Mucuna Pruriens) + L-Tyrosine. A few pills, dose was unkown. I felt it affected the middle of my head briefly and affected my cardiovascular system, felt much lighter systemically (better circulation?). I was never able to replicate this effect.