Insomnia and Its Implications

Paul L. Reller L.Ac. / Last Updated: August 03, 2017


Scientific study of sleep arousal physiology

While we tend to consider sleep as a state of complete rest, the brain is especially active, in a complex manner, during sleep. Many tasks are accomplished by the brain during sleep, and a system of controlled partial activation of specific areas of the brain, while decreased conscious perception is maintained, along with normal control of autonomic, metabolic and hormonal regulation, occurs in a cycle of different types of brain activity, called the sleep cycle, with deep sleep characterized by activation of rapid eye movements (REM) preceded by 4 stages of slowing physiologic activity and brain waves. A fine line is maintained between unconscious perception and the ability to easily arouse to a conscious state, evolved as a protective measure so that we can quickly respond to threat. The arousal system may become too sensitive to stimuli, or even to sustained fears and anxieties. The area of the brain most studied in relation to arousal and reaction to fear or threat is the amygdala, a small, almond-shaped structure of grey matter near the brainstem in the medial temporal lobe, and part of the the limbic system. The amygdala is found to be a significant modulator of brain activity during REM sleep, but much less so in the waking state, and brain studies show a lot of correlated activity with the temporal lobe during REM sleep that is not seen in the waking state. The amygdala may respond immediately to arousal stimuli and fear, or anxiety, or it may process these arousal signals through the brain. Many studies now show that acupuncture stimulation shows benefits in treating pain, anxiety and poor sleep quality by its modulatory effects on the amygdala, and connectivity between the amygdala and other centers in the brain. The measure of successful treatment for insomnia should not be whether one is sedated for 8 hours, but rather the quality of sleep, overall function, and correction of the underlying health problems causing the insomnia. Utilizing an individualized holistic sleep protocol achieves all of these goals, with the only side effect being improved overall health and prevention of future health problems.

Studies show that the amygdala behaves differently in men and women, with women generally showing more persistent amygdala responses to fear stimuli than men, as well as a tendency for a more complex response, with initial processing of fear and anxious stimuli and memory in the right amygdala, and a more prolonged response in the left amygdala, reflecting the general separation of right and left brain processing habits (the right brain generally processing data within the context of the big picture and expectations of the end result, while the left brain processes information in a more analytical, step-by-step linear and sequential pattern). Women also generally show a lower threshold for vigilance to signals of danger, and a sustained response, in studies, presumably as an evolved mechanism to better protect offspring. All of this may play a part in easy arousal during REM sleep, especially in women, causing an annoying wakefulness during the night, and often involving the feeling that the brain is too active, or that fear and anxiety is aroused, that prevents one from easily falling back to sleep. Understanding these processes allows the person with persistent insomnia to achieve an effective and thorough treatment protocol to reverse these dysfunctions in an individualized manner.

In sleep studies, many micro-arousals are noted in patients, where an actual awakening does not occur, but EEG patterns show a phasic event of arousal. Most of these micro-arousals occur in superficial sleep, stage 2 of non-REM, and REM stage, with fewer micro-arousals during the deeper stages 3 and 4 of non-REM sleep. Micro-arousals also occur more as the sleep proceeds deeper into the night, and are more frequent as the cycle goes from more superficial states of brain activity to deeper, more active states, and less as the cycle winds down from the highly active unconscious states of REM, which generally occur more frequently as the night, or sleep time, progresses. In other words, sleep studies show that the frequency of micro-arousals increases after a few hours of sleep, or towards the morning, in the timeframe of insomnias characterized by waking in the middle of the night, with inexplicable feelings of anxiety or racing thoughts.

During these micro-arousals the heart rate increases, as well as blood pressure, and muscle tone, and if a full arousal is triggered during these episodes, the waking may be disconcerting, triggering a state of vigilance, or fear. During the progression of the non-REM phases of sleep, the heart rate actually slows, and the blood pressure drops, so we know that the problem occurs in the REM sleep. When this type of arousal waking occurs, the task of the patient is to better control the reaction to arousal, so that a wakefulness doesn't disrupt sleep in a disturbing manner, as well as to work to achieve a better physiological transition to REM, and healthier REM sleep. This task may involve improvement in brain function and chemistry, as well as cognitive and behavioral corrections. Given the complexity of these arousal mechanisms, one may need to work on the emotional memories, emotional reactivity, autonomic nervous system, hormonal and cortisol functions and balance, as well as the environment, insuring that sounds, temperature changes, breezes, other other environmental triggers of vigilance are prevented during this heightened state of excitability with poor regulation of the arousal mechanisms.

Hormonal imbalances may play an important role in sleep arousal pathologies. For example, if hormonal imbalances create difficulty in thermoregulation, as in vasomotor flushing during perimenopause, it may be difficult to prevent arousal during REM sleep, where the brain activity is high, but the autonomic regulation drops the body temperature to its lowest point. If poor thermoregulation prompts the body to throw off covers during periods of flush or sweat, there may not be enough covering to insure comfort when the body temperature drops. This stress on autonomic regulation, as a result of hormonal imbalances, may also affect the control of heart rate, blood pressure and respiration, creating episodes of alarm during the sleep, and thus stimulating arousal. Restoring healthy hormonal homeostasis may be very important in correcting sleep arousal patterns. There is also a close relationship between neurotransmitters and hormones, with a crosstalk regulation, and fluid changing of levels of neurotransmitters and hormones during sleep. Many neural cell receptors react to both neurotransmitters and hormones, and not only hormonal balance, but a better neurohormonal homeostasis is also important. Giving the brain improved bioavailability to fluidly create the levels of neurotransmitters and hormones during sleep is a goal of holistic Complementary Medicine, and while this may not be as direct as blocking neurotransmitter receptors with pharmaceutical medications, the end result may be that the physiological homeostasis of the brain is finally restored to an optimal state, ending the problem without prolonged need of medication.

Parasomnias are sleep disturbances that occur when the sleeper is aroused from sleep because the transitions in the sleep cycle do not progress smoothly, or in the right sequence, causing the sleeper to be both awake and asleep at the same time (e.g. sleep walking), or wake with body movements in response to dream during REM sleep. Often, the person wakes in an agitated state in this latter type of parasomnia, termed REM Sleep Behavior Disorder, which is similar to night terrors in childhood. Another type of parasomnia seen in adulthood, especially women, is the Sleep-related Eating Disorder, where the sleeper actually gets up during sleep and fixes some food, unaware that they are actually awake. This type of bizarre sleep activity often is the result of disruption of function in the GABA system as a side effect of the sleep medication Ambien (Zolpidem), which has been shown effective to induce sleep, but not to maintain sleep through the night. Other sleep medications may also induce such parasomnias, such as amitriptyline (a sedative), and chronic use of an SSRI anti-depressant may cause the REM cycle, which is characteristically a non-serotonin state, to be disrupted by too much serotonin. The consideration that perhaps the sleep medication works to help one fall asleep, but may also cause problems with the sleep physiology during the night should be considered. Parasomnias may be more prevalent, in mild forms, than we believe.

All of these problems with sleep homeostasis may eventually contribute to patterns of emotional upset concerning sleep and arousal that perpetuates the arousal insomnias, creating a vicious cycle that must be addressed. Fear of not sleeping and anger at not sleeping often contribute to heightened states of vigilance linked to the amygdala and overly sensitive sleep arousal. This complex and chronic syndrome is not easily overcome, but with a holistic and comprehensive protocol, based on patient understanding of the factors underlying their problem, and a step-by-step approach, the patient may find the right working relationship with a Complementary Medicine physician that will guide and facilitate this approach. Just like in the treatment of chronic anxiety mood disorders, science has taught us that we must reprogram our mind and brain, stopping the tendency to overly utilize the left brain by jumping to a big picture of negative expectations, and developing the right brain utilization, whereby we consciously look at the problem one step at a time to form the outcome. Stopping the vicious cycle of emotional upset and heightened sense of vigilance in sleep by focusing on objective and practical methods of correcting this complex set of dysfunctions and restoring homeostatic health is the ticket to success. Utilizing a good working relationship with a knowledgable Complementary Medicine physician, such as the Licensed Acupuncturist and herbalist, is a good idea.

Neurohormonal Imbalances Contributing to Insomnia

A surprising number of hormones, neurotransmitters, and even immune modulators, or cytokines, affect sleep. Well known neurohormonal molecules affecting sleep include melatonin and cortisol, but a variety of other important neurohormones may profoundly affect sleep and sleep quality when out of balance.

For instance, the hormone Leptin, produced by fat cells to regulate the amount of stored fat in the body, acts upon the brain, along with its counterpart, ghrelin, mainly in the hypothalamus, interacting with other hormones and neurotransmitters to regulate energy homeostasis. Leptin levels are profoundly affected by sleep deprivation, emotional stress and relative levels of the steroid hormones estrogen and testosterone, contributing to difficulty with weight loss and obesity, and conversely, abnormal levels of leptin, and leptin resistance, affect the sleep quality, and ability to fall asleep easily. Levels of leptin are normally higher during the night to aid sleep by inhibiting the appetite. Increases in insulin, which occurs in Metabolic Syndrome and Insulin resistance, create increased levels of circulating leptin to counter the increased appetite for carbohydrates, and eventually this may result in leptin resistance, with decreased effects of leptin or lower levels of leptin in the brain. Melatonin significantly affects the level of leptin, with increased melatonin causing a downregulation of leptin, although in the presence of insulin, melatonin also appears to increase leptin levels to facilitate normal sleep. Insulin and leptin resistance at the receptors due to prolonged excesses of these hormones eventually contributes to poor sleep quality, and may contribute to sleep apnea as well. As with all hormonal and neurohormonal activity, the regulation of these chemicals involves a more complex interaction and feedback of a quantum field of hormones and neurotransmitters.

Sleep disorders, such as sleep apnea, are associated with higher levels of leptin in circulation, and increased insulin resistance, as well as altered levels of adiponectin, and leptin resistance. Studies show that sleep deprivation creates lowered levels of circulating leptin, but higher levels of leptin in the brain. Since leptin works synergistically with ghrelin on receptors of the arcuate nucleus of the hypothalamus, which also regulates temperature, sleep, and emotional arousals, abnormal levels of these hormones, improper dietary habits, insulin resistance, and melatonin dysregulation may affect sleep in a number of ways. In addition, these neurohormonal receptors on this part of the hypothalamus are regulated by dopamine, and the balance between dopamine and serotonin (5HT) may play a part in neurohormonal imbalance contributing to insomnia. A holistic protocol to achieve balanced neurohormonal homeostasis is thus important, and may need to be pursued with persistent treatment.

Leptin levels that are chronically imbalanced may lead to a variety of health problems, as well as leptin resistance at the target cells in the brain. Leptin resistance occurs with sustained high levels of circulating leptin in obesity, with increasing leptin resistance at the blood brain barrier and hypothalamus. Reduced leptin effects may eventually contribute to insomnia or poor sleep quality and parasomnias, as higher leptin responses are integral to sound sleep by suppressing appetite and contributing to hypothalamic regulation. Research has shown that high viscosity polysaccharides from the acacia tree gum, and esterified fatty acids, significantly modulate leptin and adiponectin levels in circulation. This tactic has been used to treat obesity and facilitate weight loss, but may also be applied in cases of insomnia. In addition, this type of research shows that mild dopaminergic herbal chemicals, such as Mucuna, Muira and St. John's Wort, and 5HTP, or L-Tryptophan, may be applicable to this therapy, as well as low dosage of melatonin.