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Biology 202
2001 Second Web Report
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PMS: How Much Do We Really Know?

Karen Munoz

"Basically, PMS has been piecemealed. It's like the story of the five blind men and the elephant. One checked the trunk, another the leg and so on, but nobody has the full picture." --Dr. Susan Thys-Jacobs (1).

The Controversy

There has been much controversy over the biological factors involved in the mood disorders and discomfort felt by countless women before the onset of menses. The common term for this discomfort is pre-menstrual syndrome (PMS). PMS is a disorder involving hormonal changes that trigger disruptive symptoms up to two weeks prior to menstruation. While for many women the symptoms are not severe enough to require treatment, 12 % (5 out of 40 million) are medically treated for their symptoms (2).While many scientists have supported the existence of PMS, the exact causes and treatments have created some controversy. It is not clear how much of the presence of PMS is due to physiological factors (such as hormones) and how much is due to psychological and societal factors. What role exactly has society played in the perception of symptoms? In what capacity is the I-function involved?

The Symptoms

PMS affects approximately 8 out of 10 women. Since the 1930s, the grouping of symptoms has remained fairly consistent. An American neurologist originally described these characteristics in 1931. The symptoms are grouped as follows:

"A- Anxiety: irritable, crying without reason, verbally and sometimes physically abuse, feeling "out of control", or Dr. Jekyl-Mr. Hyde behavior changes.

D- Depression: confused, clumsy, forgetful, withdrawn, fearful, paranoid, suicidal thoughts and rarely suicidal actions.

C- Cravings: food cravings, usually for sweets or chocolate; diary products including cheese, an on occasion, alcohol or food in general.

H- Heaviness or Headache: Fluid retention leading to headache, breast tenderness, abdominal bloating and weight gain" (2).

Hormones

Withdrawal theory

Dr. Sheryl Smith and colleagues in Philadelphia have devised a theory hypothesizing that PMS is caused by withdrawal of a woman's own hormones. The progesterone levels are increased during the second half of the menstrual cycle, and then there is a dramatic drop right before the premenstrual period. Progesterone, however, is converted to alopregnanolone, which acts like a sedative, increasing the potency of Gamma amino buteric acid (GABA). The presence of GABA produces mild euphoria. This theory hypothesizes that it is the sudden decrease that creates feelings of depression. The body, in effect, goes into withdrawal. She conducted an experiment in which rats were administered progesterone for three weeks and then induced them into withdrawal (both progesterone and alopregnanolone). As a result, the rats became more anxious. Studying the brain of these rats showed that this withdrawal changed the socket into which GABA connects, preventing GABA from calming the brain as it usually does. To counteract this effect, they used a substance which inhibited this outcome, and concluded that they could block the behavioral effects of the progesterone withdrawal. The implications for this hint at the need to create a drug that accomplishes the same results in humans (3).

More drug treatment theories

There have been a variety of treatments used to help alleviate PMS symptoms. Some address the psychological nature and others the physical. In the past, women have been described hysterical, and the treatments have been aimed at rectifying this abnormality. Psychotropic drugs have therefore been used in treatment, as well as tricyclics, tranquilizers, and selective serotonin reuptake inhibitors. However, when used for more than a few menstrual cycles, the limitations become apparent as they do not address the hormonal problems. There have also been many side effects including sleepiness and forgetfulness (2).To address the hormonal aspects of PMS, treatments including injection of aqueous progesterone have found to be effective. In addition, an English family practitioner named Kathrina Dalton, has also conducted studies administering Danazol, a drug taken continuously that controls the rise and fall of estrogen levels. Studies have shown the drug effective in 80% of the patients (2).

Brain Disorders

A slow-wave brain disorder

It has been proposed that PMS is due to a slow-wave brain disorder, characterized by an excess of delta waves. Other diseases characterized by slow-waves are ADHD, Chronic Fatigue Syndrome, Minor Head Injury, and Toxic Trauma. There have been successful treatments of these diseases as well as PMS with both biofeedback techniques and photic stimulation treatment, suggesting that both of these techniques address the brain wave disorder.

Biofeedback treatment

Since the symptoms of PMS are highly variable and not unilateral, it is best described as a condition of disregulation. Because of this, EEG biofeedback techniques are used to treat not only PMS symptoms, but also the entire person. EEG biofeedback works by displaying the brain waves to the individual. Through this process, he or she can learn to change them (4).Two studies (in 1995 and 1997) concluded that those who completed the biofeedback program experienced less emotional and physical symptoms, some to the point of extinction (5) (6).

Photic stimulation treatment

In photic stimulation treatment (flashing light therapy), the patient wears a mask over both eyes that shuts out all outside light. Inside the mask are red LED lamps that flash alternately. The brightness (ranging from 10 to 45 mcd) and frequency (ranging from 0.5 to 50 Hz) of the flashes are controlled by the patient. The mask is used for 15 minutes a day during their menstrual cycle. A study done in 1997 (Anderson, Legg, & Ridout) on 17 women with severe PMS participated in this study and at the end of the trial, 12 of the women no longer had symptoms of PMS (6).

The brain-wave theory hypothesis vs. The cerebral blood flow hypothesis

Since PMS is thought to be caused in part by a slow-wave presence, it is possible that an effective treatment would be increasing the frequency of the brain waves. However, this has been inconclusive, as frequencies chosen by the patients involved in the photic stimulation treatment do not choose the highest frequency change. Rather, it is possible that PMS is due to hypoperfusion, that is, insufficient cerebral blood flow. This has been shown to be the case in all of the aforementioned diseases (ADHD, Chronic Fatigue, etc.). However, the relationship between slow-wave and hypoperfusion is not well established. One theory is that because there is less neuronal activity, the blood flow is diminished. It is also possible that the reverse is true or it may be a continuous cycle of the two causes (6).The possible incorporation of both photic stimulation treatment and neurofeedback seems to be the best solution. The photic stimulation would be used to train the brain to the proper frequency, and the neurofeedback would give the patient self-control as well as attacking the specific area where neuronal activity and blood flow seem deficient (6).

The Question of Societal Influences

The existence of biological factors in the occurrence and severity of PMS has long been in question. Studies conducted have been able to provide little conclusive results due to the nature of self-reporting. Critics have dismissed such studies because the subjects know what is being studied and cannot remain unbiased. Several studies, however, have been conducted which attempt to separate the bias of self-report by conducting a blind study in which the womens' perceptions of their cycle phase were separated from their actual cycle phase. The results of these studies indicate that women who were led to believe that they were premenstrual reported (told that a machine was developed that would predict when menstruation would occur) experiencing a higher degree of physical symptoms than did women who were led to believe that they were intermenstrual. There were also slight although insignificant increases in negative affect and behavioral reported in the women led to believe that they were premenstrual. This leads to the implication that society and perceptions of PMS influence the severity of the symptoms experienced by women (7) (8).

Other Causes

There have been two recent studies with intriguing results. One study conducted by David Rubinow and Peter Schmidt at the NIMH in 1998, concluded that while estrogen and progesterone need to be present for the onset of PMS, the hormones alone were not the cause of the symptoms (1).The other study conducted by Dr. Susan Thys-Jacobs hypothesized that calcium deficiencies were the root of the symptoms caused by PMS. She researched the effect of calcium in a bone-density trial and studied women with and without symptoms. She concluded that PMS is not a mental disorder, but rather it was the body's way of telling a woman of her calcium deficiency on a monthly basis (1).It has also been proposed that PMS is caused by the body's inability to metabolize fatty acids effectively, resulting in a buildup of these unmetabolized fatty acids, degenerating typical cellular functions (9).

Implications

The exact causes of PMS remain a mystery. Many theories have been proposed, but as a result of the vagueness and inconsistency of studies, the treatments can be no more than speculations. It is clear that there is more involved than merely physiological factors-that emotional and societal factors also influence the perception of PMS. The power of the mind and the I-function certainly play a role, but how large this role is, is unclear. Certainly, what we are taught to believe affects what we feel. Our mind have tremendous influence over our behavior, despite what biological factors may be involved. Further study is needed to disentangle the myths associated with PMS, as well as the exact nature of hormones, emotions, and other psychophysiological factors.

WWW Sources

1) PMS and PMDD Cause Serious Suffering

2) Medical Treatment of PMS

3) The Health Report-PMS

4) What is EEG Biofeedback?

5) EEG Biofeedback Training for PMS

6) PMS, EEG, and Photic Stimulation

9) The Many Faces of PMS

Additional Sources

7) Slade, P. (1984) Premenstrual emotional changes in normal women: Fact or fiction? Journal of Psychosomatic Research, 28. 1-7.

8) Ruble, Science Vol. 197


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