How Does a “Steel Trap” Mind Evaporate into an Unresponsive Mist?
A Quick Tour Through the Gray Matter
How many neurons are in the average brain? Hint: if you were to count one neuron per second, around the clock, it would take over 2,720 years. Researchers tell us there are about 86 billion neurons and 84 billion non-neuron (glial) cells in the brain.
If that’s not mind-numbing enough, consider that the typical neuron is electrically networked to approximately 10,000 other neurons. That’s over 840 trillion synaptic connections in the brain!
As mentioned previously, each electrical impulse is passed from one neuron to the next across a synapse (the small space between neurons) with the help of a neurotransmitter. Considering the vast numbers of neurons and the countless impulses that move through this “electrical grid,” it quickly becomes apparent that a tremendous amount of energy and large volumes of neurotransmitters are required to keep the brain functioning at optimal levels.
Aside from the impact of certain heavy metals and other neurotoxins (which we won’t discuss because it is beyond the scope of this book), there are four major factors that impede normal brain function:
- A lack of cellular energy within the neurons
- Impaired synaptic function
- Oxidative stress
- Accumulation of metabolic debris in the brain such as the sticky, tar-like globs of waste from glucose metabolism (Advanced Glycation End-Products [AGEs] and fibrous protein fragments (beta-amyloid plaques)
Each of these factors is worsened by chronic stress. In fact, the same excessive cortisol levels and various chemical substance deficiencies that chronic stress promotes result in converting muscle to fat, contribute to decreased cognitive function and memory.
Cortisol and the Mushy Mind
In the initial stages of a “fight or flight” situation, cortisol actually helps the brain to function better by shutting down unnecessary functions and providing essential glucose to the brain through the breakdown of proteins.
Neurons, just like muscle cells, run on adenosine tri-phosphate (ATP) fuel that is generated by each cell’s mitochondria. Normally, the mitochondria need lots of glucose in order to create the high-energy ATP molecule. When a neuron is glucose-starved for too long, it will die, and unlike most other bodily cells, it will not be replaced.
The continued presence of excessive cortisol levels increases insulin resistance, however. Insulin resistance hinders the movement of glucose out of the blood and into neuronal cells.
Several things can make cells more resistant to insulin, including:
- A diet high in carbohydrates
- Over-exposure to insulin
- A sedentary lifestyle
- Sleep deprivation
- Chronic, unresolved stress
Another aspect of chronically high levels of cortisol include higher blood pressure which increases the risk of stroke and heart attack.
Stress induced cortisol levels in the blood negatively impact the synthesis of the primary neurotransmitter in the brain: acetylcholine. The excess of cortisol increase insulin resistance, insulin resistance limits the passage of glucose into brain tissues, and limited glucose in these neurons restricts mitochondrial synthesis of acetyl CoA.
As stated previously, without acetyl CoA, stores of depleted acetylcholine (ACH) cannot be replenished. Insufficient levels of ACH hinder the stress response reset and contribute to sluggish mental function.
Insulin Resistance and Cognitive Dysfunction
Insulin resistance in the brain is serious! Those with Type 2 Diabetes (chronic insulin-resistance), are 4 times more likely to develop Alzheimer’s disease than those who are not. In fact, insulin resistance in the brain is a major contributing factor in nearly every neurological disease. So much so that some are calling the brain’s resistance to insulin “Type 3 Diabetes.”
The conversion of glucose into energy can produce globs of sticky, tar-like substances called Advanced Glycation End-Products (AGE) that deposit in various places in the body. When deposited in brain tissues these obstructive substances can disrupt normal neuronal and synaptic function. Interestingly, large quantities of AGE are almost always found in the brains of Alzheimer’s patients.
Frequent insulin/glucose imbalances, like those seen in chronic stress or diabetes, cause AGE to form much more quickly. In fact, diabetics form AGE up to 5 faster than non-diabetics and are much more likely to develop Alzheimer’s disease.
Acetylcholine Deficiency and Cognitive Dysfunction
It’s fairly easy to see that a shortage of neurotransmitters would impair memory and cognitive function. Considering the aforementioned 840 trillion synapses in the brain, the demands for acetylcholine are substantial. That means that sufficient supplies of choline are required to synthesize the necessary quantities of this neurotransmitter.
Since brain neurons are much more active during times of stress, the need for neurotransmitters like acetylcholine is much greater. As mentioned in the previous chapter, the stress response can quickly deplete bodily stores of choline and may contribute to brain fog and a hazy memory.
Phosphatidylserine and the Brain
Although the evidence is still sketchy, the FDA does allow labels on phosphatidylserine supplements to state that consumption of phosphatidylserine may reduce the risk of cognitive dysfunction with the disclaimer that at present there is very little scientific evidence that supports the claim.
We do know that phosphatidylserine (PS) plays at least two important roles in the metabolic reset stage of the human stress response: 1) clearance of cellular debris and 2) reducing the release of cortisol. As discussed above, the adverse affects of excessive cortisol levels are manifold and therefore the benefits of reducing these levels are enormous.
Oxidative Stress and Neuron Dysfunction and Death
Oxidative stress is a culprit in many of the processes that lead to a lack of neural energy and the obstruction of neural impulse transmission across synaptic junctions, but it often participates in an internal disruption of essential neuronal processes that can lead to irreversible loss of the neurons themselves. One such process involves the formation of neurofibrillary tangles.
Neurofibrillary Tangles. Neurons contain capillary-size microtubules that help transport nutrients and other substances throughout the nerve cell. These transport structures are comprised largely of a protein called tau. High levels of oxidative stress can damage the tau, and that can cause the microtubules to collapse and/or to fill with AGE. When this happens it forms twisted fibers called neurofibrillary tangles.3 Eventually this process cripples and even kills the neuron.
Combating the Muscle Wasting and Mind Evaporating Forces of Stress
By now the common culprits in muscle wasting and cognitive decline should be apparent: cortisol, insulin-resistance, volatile serum glucose levels, oxidative stress, insufficient choline, and interruption of ATP production by the mitochondria.
The next two chapters will show you how simple lifestyle changes and key supplementation can help you Reverse the Tide that threatens to pull you into a worsening spiral of muscle wasting and increasing mind fog.