공포에서 벗어나려는 생명체, 정신의학에서 특히 불안이 중요한 문제가 되는데 뇌의 입장에서 보면 두려움/공포라는
보상회로를 일단 거론하지 않을 수 없다.
불안을 대치할 수 있는 보상회로의 활성화가 곧 불안을 제거하는 하나의 방법론으로 부상할 가능성을 생각하기 때문이다. 그 보상회로가 어떻게 되어있느냐는 것, 우선 필요한 더보기 참고 사이트를 소개한다.
그 소상한 내용은 별도로 상세히 설명할 기회를 남겨둔다. 이것은 Sex and Brain이란 측면에서 이른바 쾌감 센터가
어디쯤에 있느냐는 것과도 상관될 수 있는 문제다.
앞에서 지적한 대로 뇌의학의 입장에서 쾌감을 효율적으로 대치할 수 있는 불안/우울에 대한 방법이 규명된다면 새로운 치료분야가 개척되는 셈이다. 현재 화학적(약물학적) 전기적 뇌에 대한 연구자료가 뒷바침되고 있으나 기본적 paradigm은 입장에서 근원적으로 같은 것은 아니라 본다.
더보기 참고/출처 사이트
Pleasure Center of the Brain: Light It Up
You may have heard that the brain has a pleasure center that lets us know when something is enjoyable and reinforces the desire for us to perform the same pleasurable action again. This is also called the reward circuit, which includes all kinds of pleasure, from sex to laughter to certain types of drug use. Some of the brain areas impacted by pleasure include:
amygdala - regulates emotions
nucleus accumbens - controls the release of dopamine
ventral tegmental area (VTA) - actually releases the dopamine
cerebellum - controls muscle function
pituitary gland - releases beta-endorphins, which decrease pain; oxytocin, which increases feelings of trust; and vasopressin, which increases bonding
Although scientists have long been studying the pleasure center, there hadn't been much research about how it relates to sexual pleasure, especially in women. In the late 1990s and the mid-2000s, a team of scientists at the University of Groningen in the Netherlands conducted several studies of both men and women to determine brain activity during sexual stimulation. The team used PET scans to illustrate the different areas of the brain that would light up and shut off during sexual activity. In all of the tests, the subjects were scanned while resting, while being sexually stimulated and while having an orgasm.
Interestingly, they discovered that there aren't too many differences between men's and women's brains when it comes to sex. In both, the brain region behind the left eye, called the lateral orbitofrontal cortex, shuts down during orgasm. Janniko R. Georgiadis, one of the researchers, said, "It's the seat of reason and behavioral control. But when you have an orgasm, you lose control" [source: LA Times]. Dr. Gert Holstege stated that the brain during an orgasm looks much like the brain of a person taking heroin. He stated that "95 percent is the same" [source: Science News].
There are some differences, however. When a woman has sex, a part of the brain stem called the periaqueductal gray (PAG) is activated. The PAG controls the "flight or fight" response. Women's brains also showed decreased activity in the amygdala and hippocampus, which deal with fear and anxiety. The team theorized that these differences existed because women have more of a need to feel safe and relaxed in order to enjoy sex. In addition, the area of the cortex associated with pain was activated in women, which shows that there is a distinct connection between pain and pleasure.
The studies also showed that although women may be able to fool their partners into thinking they've had an orgasm, their brains show the truth. When asked to fake an orgasm, the women's brain activity increased in the cerebellum and other areas related to controlling movement. The scans didn't show the same brain activity of a woman during an actual orgasm.
But what about people who can't reach orgasm at all?
더보기 참고 사이트