Ok, so the study I mentioned was actually on transsexuals undergoing some sort of testosterone blocking therapy, so they were looking at the effect of testosterone rather than DHT. Just for the sake of general interest, this is what the study says.
"Subjective erectile function, according to IIEF-15 scores, and penile CDU findings did not correlate with testosterone levels, whereas NPT test findings correlated well with testosterone levels. These findings would suggest that nocturnal erections are androgen-dependent whereas sexually induced erections are androgen-independent. It can also be assumed that testosterone is important but not essential for male erectile function and that other androgen-independent pathways can be responsible for sexually induced erections."
http://www.ncbi.nlm.nih.gov/pubmed/15175636
I also found this:
" In a double-blind placebo-controlled study using nocturnal penile tumescence (NPT) as an objective method of assessing erectile function, finasteride (5mg/day for 12 weeks) failed to suppress consistent sleep- related penile erections.[SUP] [16]"
[/SUP]http://www.jcasonline.com/article.asp?issn=0974-2077;year=2009;volume=2;issue=1;spage=12;epage=16;aulast=Anitha
"Subjective erectile function, according to IIEF-15 scores, and penile CDU findings did not correlate with testosterone levels, whereas NPT test findings correlated well with testosterone levels. These findings would suggest that nocturnal erections are androgen-dependent whereas sexually induced erections are androgen-independent. It can also be assumed that testosterone is important but not essential for male erectile function and that other androgen-independent pathways can be responsible for sexually induced erections."
http://www.ncbi.nlm.nih.gov/pubmed/15175636
I also found this:
" In a double-blind placebo-controlled study using nocturnal penile tumescence (NPT) as an objective method of assessing erectile function, finasteride (5mg/day for 12 weeks) failed to suppress consistent sleep- related penile erections.[SUP] [16]"
[/SUP]http://www.jcasonline.com/article.asp?issn=0974-2077;year=2009;volume=2;issue=1;spage=12;epage=16;aulast=Anitha