Ultradian

Ultradian characterizes recurrent periods or cycles repeated frequently throughout a 24-hour day

The descriptive term ultradian is used in sleep research to describe individual stages of sleep that occur within intervals of an organism's circadian rhythm, and especially to refer to a 90 minute REM cycle in human sleep.

Some of the ultradian cyclings of the body are hormonal release, heart rate, thermoregulation, nostril dilation and appetite. The last involves rhythmic release of Neuropeptide Y (NPY) and Corticotropin-releasing hormone(CRH), stimulating and inhibiting appetite ultradian rhythms.

Ultradian Bipolar Disorder
All forms of Bipolar Disorder have a defined biological nature, apparently stemming from a common genetic factor that leads to generational morbidity. Both twins studies, and general population studies show that there is an increased chance of developing a Bipolar Disorder when either a general mood disorder or a specific Bipolar disorder is present in family members. Further research is being conducted to discriminate any environmental factors that may also play a role in onset and severity of Bipolar disorder.

Ultradian states in Bipolar Disorder are faster than rapid cycling states which imply four or more mood episodes in a year.

Rapid cycling mood states are characterized by more than four mood states within a year, and may occur within the space of a few weeks. These oscillations or cycles may last a few days, or even weeks. While current understanding looks to the presence of both states simultaneously, there are anecdotal cases where situational factors can produce distinct and separate periods of depression or mania/hypomania, switching back and forth. Because there is very little research into this particular form of cycling, the terminology is borrowed from the more established research into the formal Bipolar I or Bipolar II categories.

Ultradian cycling is characterized by cycles shorter than 24 hours. Ultradian Bipolar Disorder is productively treated by the same mood-stabilizing medications used with Bipolar I and II, though dosing may be difficult due to situational stress and other environmental factors.

Researchers are working to understand the brain chemistry basis of mood states in an effort to better diagnose and treat Bipolar Disorder. This research shows the promise of finding biological determinants for Ultradian mood states.