Steven Lamm, MD: What we're appreciating more and more is that erections, or the penis is an organ that changes with almost every decade of a man's life. We actually never thought of it that we. We always thought of erections as an all or none phenomena, but the reality is an erection at age 15, or a sexual response at age 15 is actually different than at age 30 and at age 45 and at age 60. There's a different degree of blood flow, there's a different degree of what we call rigidity due to changes in blood flow as well as connective tissue and muscle. It's an organ, and this is an organ that ages, as every other organ does. So that you can't play baseball the same way at 55 as you did when you were 20, you can't see as well, you can't even think as quickly probably. So why do we assume that this organ somehow doesn't age? And so the issue is can we slow the aging process down?