Braincycles

Scientists have long known about “braincycles,” but few people in the general public seem to understand them or make good use of that knowledge, except perhaps intuitively or inadvertently. Braincycles are variations in the brain’s focus of attention, ranging through a period that averages roughly ninety minutes. In one part of the cycle, your brain pays close attention to the outside world, that is, the incoming “data” from the senses. During this phase, you’re consciously involved in interacting with our environment, such as when reading or listening attentively to what someone is saying. During the other phase of the braincycle, your brain withdraws its attention from the sensory data stream and turns inward, processing its own stored images, sensations, reveries, thoughts, and musings. In everyday language, we say that your mind is “wandering.” This brainstate is usually easily observed in another person by watching his or her eye movement, facial expression, and diminished motor activity. One can immediately think of practical applications for just this one simple but important aspect of brain function. For example, you may observe that your boss seems to be distant and detached from the conversation, indicating that his or her brain is temporarily “off line” (to use an Internet analogy).You might decide to wait until another time to bring up a complex or critically important issue that requires his or her full concentration—your raise, for example—a time when the brain is back “on line.” As another example, consider that there are certain times when you seem to be in the mood for work that requires close attention and concentration, and at other times you find it more difficult to focus on details.To the extent that you can choose, you can tackle certain tasks when your brain cycle is in the right phase for the job. We can directly apply findings like these to human performance management. How many data-entry errors, short-changed customers, industrial accidents, car crashes, surgical blunders, and maybe even plane crashes might be associated with braincycles? Can we provide job aids and skill training to reduce these effects?1 This attention cycle—the shifting of attention between on-line and off-line phases, is just one of many cyclic patterns exhibited by the biocomputer. When we consider the number and variety of other cycles, we can see that the system is like a collection of oscillators, or perhaps like a collection of musical instruments, each playing its own melody. Scientists refer to daily cyclic patterns as circadian rhythms—from the Latin root, which means “about a day.” Perhaps the most obvious circadian pattern is the cycle of sleep and wakefulness. Researchers also identify ultradian cycles, or patterns that repeat several times within a day, and infradian cycles, which span across multiple days. Among the ultradian patterns we have the obvious but taken-forgranted cycles of heartbeat and respiration. Somewhere in the biocomputer, or perhaps at various points, we have oscillators that keep our vital processes going. Our body temperature tends to rise and fall throughout the twenty-four-hour period.The chemical composition of our blood and various other bodily fluids tends to cycle throughout the day. Appetite and digestion follow their own cycles. Sexual arousal and release follows its own cycle. The attention cycle, described above, is also a primary ultradian pattern. A particularly curious ultradian pattern is the so-called nasal cycle, which seems to vary over a period of about ninety minutes. At various times over the cycle, one nostril or the other will be more dilated, with a freer flow of air—provided your nasal passages aren’t congested— and the other will be less open. Sometimes during the cycle they’ll both be about the same.To test this, press one nostril closed with your fingertip and notice the volume of air as you inhale through the other nostril.Then switch to the other side and compare the flow rates. Some researchers have speculated that this nasal cycle is linked to a cycle of cerebral activity in which either the left cerebral hemisphere or the right one is more active, although there seems to be some controversy about this connection. One of the most noticeable infradian patterns is the female menstrual cycle of about 25 days. Over a much longer span, the gestation period for human females is about 280 days. In between, there seem to be human cycles of adaptation based on changes in seasons, the weather, and the amount of daylight. We have many other cycles built into our biocomputers. Consider various rhythmic physical activities such as walking, which are controlled by the cerebellum. Keeping time to music, singing, dancing, and marching all involve built-in oscillators. Even commonplace motor activities such as knocking on a door, brushing your teeth, and washing your hands involve rhythmic patterns.The compelling rhythm of sexual intercourse responds to oscillators programmed deeply into the biocomputer. Consider also the cadence of ordinary speech. The native users of any particular language all tend to follow a distinctive rhythm, or alternating pattern of emphasis. Read the following passage from a poem by A.E. Housman and sense the rhythmic pattern of the language, marked off by the rhyming syllables: And how am I to face the odds of man’s bedevilment, and God’s? I, a stranger and afraid in a world I never made.