Reddit reviews The Science of Orgasm

You're welcome! If you are interested in the topic, I'd highly recommend two books: "Psychopharmacology and Women: Sex, Gender, and Hormones" and "The Science of Orgasm". Both cover, compare, and contrast male and female sexual response with a focus on the biology. They are a few years old but I can't imagine that there have been many earth-shattering breakthroughs (ha ha) in the field since then.

There is a lack of information in the scientific community, but a reasonable guess would be that male orgasm has some vagus nerve involvement. The vagus nerve is unique in that it branches from the brain stem, forks, and runs separate from the spinal cord.

The role of the vagus nerve in orgasms is a new discovery and there's still much that's unknown about it; until recently, researchers didn't know that it passed through the pelvic region at all.

In general, sexual feeling is transmitted by:

hypogastric nerve - the uterus and the cervix in women and from the prostate in men

pelvic nerve - the vagina and cervix in women and from the rectum in everyone

pudendal nerve - the clitoris in women and from the scrotum and penis in men

Since all of those nerves are associated with the spinal cord, it would stand to reason that a person with a severed spinal cord wouldn't be able to have an orgasm. And for a very long time, that's what people with these types of injuries were told.

Dr. Barry Komisaruk and Dr. Beverly Whipple of Rutgers University conducted a study on women with severed spinal cords in 2004. They used MRI to confirm that these women could feel stimulation of their cervixes and even reach orgasm, although there was no way their brain could be receiving information from the hypogastric or pelvic nerves.

They published a companion book in less technical language with additional content.

EDIT: formatting, also bad link

Dopamine is intimately involved in the regulation of sexual drive and behavior.

I can't link you to the place in, but there is a chapter in this book, The Science of Orgasm, titled "The Neurochemistry of Orgasm", Chapter 10. In it, it expands on the two neurotransmitters involved in ejaculation: dopamine and serotonin.

It talks about dopamine as a trigger for sexual behavior.

In regards to a study, relevant in that they referenced the study where dopamine caused premature ejactulation:
>Dopamine receptor antagonists such as haloperidol produced the opposite effect... decreasing the number of intromissions and ejaculations by 50%.

In regards to serotonin, it then talks about serotonin as a "brake" on sexual behavior.

Another book to check out is:

The Psychophysiology of Sex (Kinsey Institute Series), but only if it's in the book store. It's expensive.


Another source for Dopamine/Sex study:

• CS05-02 - The involvement of dopamine in human sexuality
  
  From the abstract:
  
  >Studies in humans and animals have suggested that the central dopaminergic system is involved in all components of male and female sexual behavior: desire, erection, orgasm and satisfaction. Copulating activity enhances DA release in the nucleus accumbens as measured by microdialysis in male rats. This rise in DA release lasts until ejaculation and then declines during the refractory period.
  Dopaminergic agonists such as L-dopa, apomorphine, amantadine, bupropion, amphetamines and cocaine have been reported to arouse sexual behavior. Short term use of cocaine and other drugs that increase dopaminergic activity (Marijuana, MDMA) facilitate sexual desire and erection and delay ejaculation. These effects are reversed in chronic abuse when brain DA is depleted.
  Central dopaminergic blockers, like first generation antipsychotics suppress sexual functioning via the D2 receptors blockade and the corresponding elevation in plasma prolactin levels. Due to their weak antagonistic activity at D2 receptors, second generation antipsychotics are associated with fewer sexual side effects and thus provide an option in the treatment of patients with schizophrenia.
  Enhancement of dopaminergic activity by the addition of the DA agonists or bupropion, a norepinephrine-dopamine reuptake inhibitor, has been reported as an effective approach in the management of antidepressant-induced sexual dysfunction. The significant facilitating role of the DA system on sexual function should not be viewed independently. The dopaminergic system interacts with other systems like gonadal hormones, Nitric Oxide and serotonine in the complex neurobiology of sexual function.
  
  
  
• Ejaculation induces long-lasting behavioural changes in male rats in the forced swimming test: evidence for an increased sensitivity to the antidepressant desipramine
  
  The abstract:
  >Copulation to exhaustion induces a sexual inhibitory state featured by a decreased motivation. Since diminished motivation is a key symptom of depression, we analysed if sexually exhausted animals showed increased levels of depressive-like behaviour in the forced swimming test (FST). Besides, sexual activity has been reported to have reinforcing properties. Thus, we analysed whether different levels of sexual activity modified the development of the behavioural despair in the FST. Finally, the effect of a sub-threshold dose of desipramine (DMI, 2.5 mg/kg) was evaluated in animals with different sexual conditions. Male adult rats were divided into: (a) naïve rats and (b) animals executing one intromission (1-INTR) or (c) one ejaculation (1-EJ) and (d) sexually satiated rats, classified as sexually responsive (R) and non-responsive (NR). No differences were found in immobility behaviour between sexually exhausted and naïve rats. In the pre-test sessions of the FST males attaining ejaculation (1-EJ, R and NR) had lower levels of immobility or showed a tendency towards such a diminution, while animals with sexual activity not involving ejaculation did not. Data suggest a “protective” effect of ejaculation against the development of depressive-like behaviour. Finally, the sub-effective dose of DMI produced an antidepressant-like action in all animals that ejaculated. In conclusion, sexual experience involving ejaculation modifies the behavioural expression of rats in the FST and their sensitivity to antidepressant drugs like DMI. Both responses reflect brain plastic changes induced by ejaculation.
  
  
  As for the relationship with testosterone levels: Testosterone alone causes mood swings. Hormonal imbalances can wreak havoc on the body.
  
  Additionally, you get a boost of will power if you can practice some discipline. Masturbating can be an addiction, just like drugs, sex, alcohol, caffeine. Try abstaining for a week or so. I suggest picking something easy or trivial like giving up iced tea or chocolate -something you do a lot of but that won't cause real harm by the absence of it, and keep a journal of any thoughts you have relevant to your journey. You don't need long entries but try to form some thoughts to articulate what you think.
  
  What's the take away? What did you learn about yourself? How do you feel now, compared to before?
  
  
  Thanks for checking out the sources and for your reply. I hope this helps.

I read this book a couple of years ago and learned it from [here.] (http://www.amazon.ca/The-Science-Orgasm-Barry-Komisaruk/dp/080188490X)

Take it up with him.