Sophronia L. Gallop
From our experience, we know that the brain plays an important role in our sexuality. Our thoughts, emotions, and memories are all mediated through its complex mechanisms. Sexual arousal can occur without any sensory stimulation: it can be produced by the process of fantasy (in this case, thinking of erotic images or sexual interludes), and some individuals may even reach orgasm during a fantasy experience.
(figure available in print form)
We know that specific events can cause us to become aroused. Less apparent is the role of individual experience and cultural influence, both of which are mediated by our brains. Clearly, we do not all respond similarly to the same stimuli. Some people may be highly aroused if the partner uses explicit sexual language.
Others may find such words to be threatening or a sexual turnoff. Similarly, the smell of genital secretions may be more arousing to many Europeans than to members of our own deodorant-conscious society. The brain is the storehouse of our memories and cultural values and, consequently, its influence over our sexual arousability is profound.
Strictly mental events like fantasies are the product of the cerebral cortex, the “gray matter” that controls higher functions like reasoning and language abilities.
But the cortex represents only one level of functioning at which the brain influences human sexual arousal and response. At a subcortical level, the limbic system seems to play an important part in determining sexual behavior, both in humans and in other animals.
In the diagram of the brain, it shows some key structures in the limbic system. These include the cingulate gyrus, the septal area, the amygdala, the hippocampus, and parts of the hypothalamus, which plays a regulating role. There is evidence linking various sites in this system with sexual behavior. For instance, several animal studies have implicated the hypothalamus in sexual functioning. Researchers have reported increased sexual activity in rats, including erections and ejaculations, triggered by stimulation in both anterior and posterior regions of the hypothalamus. When certain parts of the hypothalamus are surgically destroyed, there may be a dramatic reduction in the sexual behavior of both males and females of several species.