Sexual activity is instinctive part of human behavior. But
the biology behind this behavior is quite complex, especially in men. For many
men, sexuality is one of the things that change over time. This change is
usually a gradual and almost imperceptible process that starts in middle age.
Experts still don’t understand all the factors that
contribute to sexual function in young men, let alone which factors are
responsible for the changes that occur with healthy aging. However, it is
obvious that the nerves, hormones and blood vessels that are responsible for
male sexuality are changing with the process of aging. Although the sex act is
a continuous process it has several stages and almost all of them are affected
by aging.
To start with, a normal sex drive represents the unity of
body and mind. This unity requires a certain level of testosterone – male sex
hormone. Sexual desire is awakened at puberty when testosterone levels are
increasing. Although the intensity of sex drive tends to decline with aging,
most men produce high level of testosterone to boost sexual desire at a good level
throughout life. For most of the older men sexual interest still exists, but it
is far from preoccupation with sex that is common in young men. Many older men
think about sex, but sometimes their body is very weak. It is also good to
point out that men show tendency to produce more female hormones like prolactin
and estradiol as they get older.
Every sexual activity starts with arousal and excitement.
This is a result of combined erotic thoughts and sensory stimulation which
usually includes sight, touch, taste, smell and hearing. The area of the brain
known as hypothalamus coordinates erotic images and feeling and transmits the
impulses of desire through the spinal cord all the way to the pelvis. The
pulses are linked to the nerves of the pelvic area which ultimately leads to a
reaction. Sensory nerves located on the penis and other erogenous zones are
connected to the nerves of the pelvis and bypass the brain. In other words, all
this happens by accident. Most men experience a worsening of sexual response
with the aging process. Stronger erection occur more slowly and they become more
dependent on physical stimulation than on erotic thoughts. Even when they have
an erection, most men in their 60s will find it very difficult to maintain a hard erection and the penis won’t be stiff as it used to be. In addition, nocturnal
erections decrease with age too.
The process of ejaculation involves the muscles of
epididymis, vas deferens, seminal vesicles and prostate. All these body pars
react automatically. At the same time, nerve impulses tighten muscles in the
bladder neck so that the semen is forced to squeeze through the urethra instead
of flowing back into the bladder. The pleasant feeling of orgasm usually comes
with ejaculation. Ejaculation changes with the aging process. Muscular
contractions of orgasm are less intense, ejaculation is slower and the semen
volume is reduced. The amount of sperm is reduced too. Healthy men can have
children in old age, but their birth rate cannot be compared with younger men.
