"No Fap" -the name for the pratice of giving up pornography and self stimulation as a means for self improvement. Easily the most frequently requested topic on this channel, so here it is. Before we start I want to clarify that masturbation itself or even pictures of naked people are not necessarily a problem. This discussion is about the brain changes made by high speed internet porn - a recent phenomenon that didn't exist until around 20 years age.
Naturally, any discussion about porn is going to start with a bit of cell biology. We are made up of two types of cells, the germ cells and the somatic cells. The germ cells' job is to hold and spread genetic material. The somatic cells' role is essentially to protect the germ cells and make sure they are able to do their job. What you conseider to be yourself, your body, is the soma. What nature wants the soma to do is to live enough to allow the germ cells to pass the genetic material off to a new soma. Whatever DNA resides in your body arrived there thanks to the perpetual ralay race a countless number of somas took part in before you or your ancetors came into existence. Nature's expection for you is to pass the baton to what weill be the next soma carrying the precious genetic material.
The point of this is to highlight just how high on the priorties list sexual reproduction is going to be for living things. Take for example the small, mouse-like creature called an antechinus. The males have very short lifespans, because at a certain point they well have finished making all the sperm that they can and lose the ability to make anymore. When they reach this point, they will aggressively mate with as many females as they can. Tirlessly having sex hours for on end to the point thar their fur falls off, they bleed internally and their immune system fails, leaving them riddled with gangrene. And they will then continue to have sex, until they die. Luckily, us humans naturally do not loss the ability to produce sperm and we are very keen on staying alive. We have a very strong imperatibe to propect ourselves, to feed ourselver, to survive - and many mechanisms are set in place to motivate us to do so.
In particular, the brain has within it the all powerful dopamine system. It's there to motivate you to do the things that would help you survive. And of course reproduction is the other very strong imperative. Maybe unsurprisingly, the dopamine system seemms to be much more reactive to chances for reproducion. Comparing a 1999 study from the University of Caglliari to 1997 Study from the University of Birtish Colombia, we can see that the dopamine output from sex is about twice as strong as what you get from food. If we go all the way back to the Paleolithic era when the hardware for the human dopamine system - the brain was being develop these reproductive opportunities didn't come very often. As James McClellan says in his book "Science and Tenchnolohy in World History "Over the entire 2 million years of the Pa;enlithic, beginning with the first species of Homo, population densite remained astonishingly low, perhaps on more than one person per square mile. " Potential reproductive opportunities would have been very limited simply. So, the brain developed certain strategies to maximize reproduction. For example, an animal will reach a sort of sexual satiation after having sex multple times with the same mate. And you will see a decline in dopamine that maches the waning motivation. However, if you introduce a totally new partner, then the dopamine and the motivation to have sex will shoot back up- this is a great strategy, it would maximize the total potential babies.
"No Fap"是指停止看色^情片和自我刺激以达到自我改进的目的。也是本频道最经常被问到的话题，那么就来谈谈吧。在开始之前我要说明自^慰或是裸^体图片不是本次讨论的问题。本次讨论的是在高速网络加持了色^情业以后，对大脑产生的种种影响-高速网络下的色^情是个约20年前不曾存在的新近的现象。
任何有关色^情的讨论自然都得先谈一点细胞生物学。我们有两种细胞组成，生殖细胞和体细胞。生殖细胞的工作室保存与传播遗传物质。体细胞的角色基本上是保护生殖细胞并且确保它们能进行自己的任务。被你视为自己的部分，如你的身体，是体细胞。体细胞自然而然想要获得足够长久让生殖细胞传递宜川物质到另一个新体细胞上。无论你体内的DNA时如何遗传的，都要归功于早在你或你的祖先存在之前无数体细胞参与的不间断接力赛。自然天性对你的期望就是将接力棒传给下一个体细胞继续承载珍贵的遗传物质。
在这里划重点，交配繁殖对于生物来说是处于极其高的优先位置。举个小例子，一种名为袋鼬鼠的老鼠样生物。它们雄性寿命非常短，因为在一个特定时间点他们会因用完所有的精子而失去制造精子的能力。当到达这一刻，它们变得主动并尽力与更多雌性交配。它们会不知疲倦地交配数小时直到皮毛脱落，直到内部出血、免疫系统崩溃、身体正千疮百孔的腐烂。就这样他们也会继续交配直到死亡。幸运的是，我们人类自然是不会失去制造精子的能力，我们也非常渴望活下去。我们有着极强本能要保护自身，许多身体机能的设定都是为了使我们能获取食物、生存下去。
特别的，大脑中有着强大的多巴胺系统。就是它驱动着你去做有益于生存的事。当然，繁殖是另一个非常强的本能。或许并不意外，多巴胺系统似乎对繁殖可能性非常活跃。将1999年卡利亚里大学的研究与1997年加拿大英属哥伦比亚大学的研究进行对比我们看到，多巴胺因性而起的分泌量是因食物而起的两倍。如果我们回到旧石器时期，当大脑正在发展人类的硬件多巴胺系统时这类繁殖机会并没有很频繁。就像詹姆斯麦克莱伦在他的书《世界科学技术通史》中所说“整整两百万年的旧石器时期，由首个人属物种开始，人口密度依然非常低，大概每平方英里（1.6公里）不会超过一个人。” 潜在的繁殖机会非常有限，因为没有那么多人可交配。所以大脑为了繁殖机会的最大化，发展出特定策略。例如，一个动物要想达到一定性满足需在与同一个交配伙伴进行数次交配。同时你可以看到多巴胺减少与动力衰退相吻合。然而，如果引入一个新伴侣，这时多巴胺与欲交配的动力将迅速回升--这是一个很棒的策略，可以将潜在婴儿总数最大化。
