A key function of the brain is to serve the needs of the body. The body signals its needs through urges, emotions, and desires that provoke the brain into producing actions designed to satisfy them. However, desires can be confusing and contradictory.
When our bodies want something, they let us know about it. An empty stomach makes itself known by producing feelings of hunger, dehydrated cells produce thirst, constricted muscles make us feel restless, and desire induces feelings of lust. These simple appetites and urgings, or ‘basic’ desires, are produced by body chemicals that act on the hypothalamus at the base of the brain, which in turn sends appropriate signals to the cerebral cortex. ‘Higher’ desires, like attraction to something beautiful, are also linked to changes within the brain. Certain images, for example, may provoke pleasant memories – not strongly enough to make them conscious, perhaps, but enough for them to produce a less intense version of the pleasurable feelings experienced when the event happened. However, human desires are often conflicting. Someone might crave chocolate – yet at the same time want to lose weight. Someone who hates the idea of being unfaithful to their partner might still be attracted to another person. Such conflicts arise because we can desire things on two levels: we feel basic, physical urges for things that offer immediate satisfaction, and we also have complex hopes and dreams that can lead us to put our instinctive urges on hold or even suppress them altogether.
Dealing with conflicting desires
Most of the time, it is fairly easy to cope with conflicting desires: for example, parents will patiently read a bedtime story to a child after a hard day’s work, even though they might prefer to relax in front of the television. The reward of the child’s pleasure offsets any irritation caused by deferring the need to relax. But if a person becomes trapped in a situation where basic desires are constantly denied, it can create a chronic state of inner tension that may eventually take its toll on health.
This is particularly true of unconscious desires. For example, take someone who looks after an elderly relative and so cannot go on holiday. At a conscious level, the desire to take good care of the relative may outweigh the desire to have a break, but unconsciously, the thought of a holiday may persist, unacknowledged. The result can be a seemingly inexplicable feeling of irritation that may come to influence the carer’s behavior. Over time, the slow build-up of stress hormones released as a result of the irritation could also lead to health problems. For this reason, it is important to try to understand your desires at every level by attending to your feelings and questioning why they occur. Being conscious of a basic desire at least enables you to deal more effectively with the frustration it brings and perhaps find some alternative way of satisfying it.
SEXUAL ATTRACTION
Sexual desire occurs on two distinct levels: on one level, it manifests as an ‘approach and go-for-it urge, while on the other, it is gentle, romantic, admiring, and usually focused on a particular individual. Brain imaging studies suggest these different types of desire occur in different regions of the brain and that romantic desire evolved much later than the basic sexual urge.
In both men and women, the basic urge is created by clusters of cells within the hypothalamus, which is concerned with emotional activity. These clusters are molded early in life by sex hormones, and those that are most developed have the greatest influence on the type of person you find attractive. The individual you choose, however, is decided by experiences encoded in the ‘higher’ regions of the brain in the cerebral cortex.
Differing responses
The two components of sexual desire are typically more separate in men than in women. When men experience ‘pure lust,’ a primitive brain area called the claustrum is activated, whereas romantic interest results in more diffuse brain activation that takes place in parts of the cortex. In women, sexual desire is typical of this more diffuse kind, and this is more integrated with the basic urge.