Neurotransmitter Pathways affecting Concussion, TBI, Stress, Depression, Tremor, Stroke, and Anxiety

securedownloadNeurotransmitter Brain Food:  Rebuilding  the Acetylcholine (Choline or Lecithin),  Serotonin (5-HTP or tryptophan)  and Dopamine (Tyrosine) Neurotransmitter Pathways.  

A Case Study Attacks  Stress, Anxiety, and Tremor with pathway amino acids, choline (lecithin) and co-factors.

A middle-aged female with a family history of anxiety and Parkinson’s Disease developed a tremor and mild pain in her left arm. She had a history of painful joint injuries and anxiety due to job-related stress. She obtained little exercise and used ibuprofen (Advil) therapy for the  joint pain. At work she occasionally painted the interior of homes, often inhaling the fumes.  She reported awakening in the morning with an upper body tremor and a cold left arm.  Her fists would be tightened and her hands tingly. During the day, her extra-ocular muscles were painful and she had difficulty focusing.  She experienced somewhat normal energy levels during the early part of each day and then fatigued.  Athletic stress, work place stress, intense mental concentration, painting, an emotional event, sugar or deep-fried food ingestion stimulated the tremor and reduced her energy levels.  At bedtime, upon turning off the lights, she experienced vertical gaze problems.

Her daily vitamins included vitamin B complex (100mg b.i.d. (twice daily)), vitamin C (500mg t.i.d. (three times daily)), amino acids (1500mg t.i.d), fish oil (1g), calcium citrate (600mg), calcium phosphate (600mg), iron (65mg), coenzyme Q10 (200mg), lysine (500mg), beta-carotene (10,000 IU), zinc (50mg), and a multi-vitamin.

She has a family member who has been on standard of care therapy for Parkinson’s Disease for the past 7 years but the disease has progressed. To alleviate her left arm tremor, she began ingesting choline and lecithin in increasing amounts, until the tremor subsided.  During the first weeks of therapy, she experienced a mild frontal lobe headache, more significant on the right side.  Stressful days would be followed by the upper body shiver and left arm tremor, the next morning upon awakening.  Sugar ingestion stimulated the tremor within an hour.  A stressful work situation stimulated the upper body tremor. She slept quite heavily during the first two months of choline and lecithin therapy.  Attempts to reduce the choline and lecithin dosages re-established the tremor.

During the third month of therapy, heavy stress continued  at work. She was anxious and had a negative outlook. To alleviate the sleepiness brought on by the choline/lecithin supplements, provide more energy,  and support the dopamine pathway, she began taking tyrosine.  To fortify the serotonin pathway and improve her mental outlook, she added 5-hydroxytryptophan (5-HTP).  There were positive results the first day.  With the tyrosine and 5-HTP, she was able to perform more of her normal daily activities. In time, with the combination of these supplements, the natural oils returned to her skin and menses became painless.  She continued to decrease stress levels and overwork.  She rested frequently.

The adrenal glands are responsible for producing many neurotransmitters.  They are small walnut shaped glands resting on top of the kidneys which produce cortisone and neurotransmitters in response to stress.  To help her adrenals, she began taking a bovine adrenal rebuilder, the amino acid methionine (controls the adrenals), minimal amounts of sugar, no high fructose corn syrup, no deep-fried foods nor alcohol.

At the beginning of the fourth month, she continued 95% tremor free.  Her left arm continued to experience mild pain depending upon sugar and choline/lecithin levels.  She experienced improvement in her daily energy level and her arm tremor and pain resolved almost completely.  The left arm would experience some irritability after stressful days or skipped choline/lecithin supplements.

At 4 ½ months post tremor initiation, the subject was pricked with a garden thorn.  It appeared that her blood had thinned. She had experienced no side effects of choline (nausea, vomiting, diarrhea, sweating, increased sweating, or salivation (Livestrong Website)) nor side effects of lecithin (rash, low blood pressure, diarrhea, vision problems, fainting or loss of appetite (Headquarters Website)). However, internet research showed that blood thinning may occur with choline/lecithin. She began using  ibuprofen and aspirin sparingly. She decreased her dosage of lecithin, however, the tremor returned.  She resumed the lecithin dosage and purchased a multi-vitamin containing vitamin K and increased green food consumption.  (Vitamin K which is found in greens is important in the blood clotting process).

At five months post tremor her left arm was the same temperature as her right arm upon awakening. The fists and tingling findings were infrequent. The left arm continued to have some irritability after stressful events.  Exposure to paint fumes initiated the tremor. Relief from tremors, extraocular fatigue, body twitches, and spontaneous crying was found with additional choline and lecithin. She experienced some daily facial flushing and left sided chest pain/pressure with exercise.  Knowing methionine is stored in the heart, she reduced her daily methionine intake.

More research as to the benefits of choline, lecithin, methionine, and tyrosine to improve neurological health may be beneficial.  Urine amino acid testing is available and would be important to utilize more frequently to determine amino acid levels pre and post amino acid or pharmaceutical therapy.  Better availability of a urine amino acid neurotransmitter test that specifically provides tyrosine, tryptophan, choline and co-factor levels vital to support the three important neurotransmitter pathways would be beneficial.  We expect that Wellness 2020 will bring these advancements.  For a complete discussion of Wellness 2020 see the home page of

Neurotransmitter  Discussion:

Nerves are key to communication within the body. They tell a muscle to move or an organ to function. It takes two nerves, one from brain cortex to the spinal cord and a second from the spinal cord to the foot, to make the foot move.  Nerves communicate through chemicals similar to a car battery.  The nerve running from the brain to the spinal cord will pass a chemical called a neurotransmitter to the nerve running between the spinal cord and the foot to stimulate the receiving neuron. Neurotransmitters travel from the sending neuron to the receiving neuron through a gap (cleft) and they are frequently recycled back into the sending neuron to use again.  The adrenal glands play a key role in producing neurotransmitters from amino acids and dietary protein.

Electricity traveling through a battery or a house is either turned on or off, making man’s design of current either excitatory or off.   The Creator’s design is a bit more elaborate in that it involves both excitatory and inhibitory transmissions.  Epinephrine, acetylcholine, and glutamate are mainly excitatory neurotransmitters while dopamine, norepinepinephrine, and GABA (gaba-amino-buteric-acid) are inhibitory.

On the Concussion Brain Food post at we discussed the importance of Omega-3 fatty acids (cell membrane formation), B-complex (nerve formation), and Amino Acids (protein/neurotransmitter formation) for healthy brain and nerve tissue.  This Neurotransmitter paper examines the three main neurotransmitter production pathways: ACETYLCHOLINE, DOPAMINE, and SEROTONIN and the amino acids and vitamins required to keep these cells healthy and alive.



I.  Production of  ACETYLCHOLINE:


Phosphatidylcholine (Lecithin)   —->  Glycerophosphatidylcholine   —> Choline   

Choline  +   Acetyl  Coenzyme A  —->   Acetylcholine


Acetylcholine functions as both an inhibitory and excitatory neurotransmitter controlling many of the body’s nerves including excitatory skeletal muscle contraction and inhibitory actions on the heart and brain.  The body can convert phosphatidycholine (lecithin) to glycerophosphatidylcholine and then to choline.  The body makes the acetylcholine neurotransmitter by adding acetyl coenzyme A to choline.  Choline is used for cell communication and used to produce phosphatidylcholine and sphingomyelin which make cell membrane (Linus Pauling Institute). Choline contributes to the production of the myelin coating around nerves (Oshida K et al., 2003) and it supports the folate pathway to produce DNA (Institute of Food, Medicine, and Nutrition Board, 1998). The three neurotransmitter pathways described in this paper appear to depend upon each other’s viability.  Acetylcholine, for example, has an important role in activating the Dopamine Pathway.  Normal levels of the dopamine pathway neurotransmitters may not be produced without sufficient levels of acetylcholine to act as a stimulus (Patrick RL et al.,1971).  Low choline and dopamine levels have been implicated in Parkinson’s Disease (Zurchovsky L, 2012).

Choline is an essential nutrient and it is water soluble, therefore must be replenished daily in the diet.  Choline is found in foods such as eggs, fish, liver, milk, wheat germ, and quinoa and is available as a supplement as choline or lecithin.  Since choline plus acetyl coenzyme A make acetylcholine, sufficient quantities of both must be present. Adequate intake levels of choline for healthy individuals are 425-550mg/day (Linus Pauling Institute).

Low choline levels have been found to correlate with anxiety, intelligence and worry (Coplan JD et al., 2012).  Liver and muscle damage (Sha W et al., 2010) athlerosclerosis, neurological disorders (Ziesel SH, et al., 2009),  infertility (Johnson AR et al., 2012),  and growth impairment (De Simone R et al, 1993) are promoted with deficiencies. Those who do not eat enough whole eggs may be at risk (Hasler CM et al., 2000).  Choline is in high demand during pregnancy and helps to prevent neural tube defects (Pitkin RM, 2007).

Choline, B9 (folate), B12 (pyridoxal phosphate), and methionine have key roles in the methyl donor system and cancer protection (Kadaveru K, 2012). Diets rich in choline may lower the risk for breast cancer (Xu X et al., 2009), promote REM sleep (Kushikata F, 2006), and memory (Zhang W et al., 2012). Choline has been used as a treatment for Alzheimer’s disease (Zhang W, 2012), and stroke (Gutierrez-Fernandez et al., 2012).  Choline is being studied to help treat traumatic brain injury. Choline or lecithin can be useful in treating neurological disorders characterized by inadequate release of acetylcholine such as Tardive Dyskinesia (described as involuntary, repetitive facial or limb movements,  Growdon JH,1978). A single meal containing lecithin increases concentrations of choline and acetylcholine in rat adrenals and brain tissue (Hirsch MJ, 1978)  Perinatalcholine is neuroprotective for seizures, depression, and the effects of alcohol (Glenn MJ et al., 2012). Ninety percent of humans in a research study conducted had choline below adequate levels (Zeisel, 2009).


II.  Production of  SEROTONIN:


Tryptophan   ——————>     5-Hydroxytryptophan (5-HTP)   

5-Hydroxytryptophan (5-HTP) ————–>  SEROTONIN  (5-HT, 5 -Hydroxytryptamine)

The Tryptophan to 5-HTP conversion requires Vitamin B3, B9, Iron and Calcium, and is facilitated by the enzyme tryptophan hydroxylase

The 5-HTP to Serotonin conversion requires Zinc, Vitamin B6, Vitamin C, and Magnesium and is facilitated by the enzyme dopa decarboxylase

.(Enzymes and cofactors required to produce 5-HTP and 5-HT from the Understand and Cure Website.)


Tryptophan, an essential amino acid for humans, makes serotonin.  It must be included in the diet, humans are unable to produce it. Tryptophan is found in eggs, spirulina, fish, poultry, nuts, seeds, organic soybeans, milk, and cheese.

To convert tryptophan into 5-HTP and produce serotonin (5-HT, 5-hydroxytryptamine) an enzyme called tryptophan hydroxylase(TPH) is required with the cofactors vitamin B3 (niacin), B6 (pyridoxal-5-phosphate), B9 (folate), vitamin C (ascorbic acid), magnesium, iron, and calcium.  High  fructose corn syrup may decrease absorption of trytophan from the gut (Ledochowski M, et al., 2001) thereby reducing the quantity of TPH enzyme and serotonin produced.  The Parkinson’s medication carbidopa-levadopa (Drugs.Com Website) is known to interfere with tryptophan, thus TPH and serotonin production.

Ninety percent of serotonin is stored in the chromaffin cells of the intestines (Donnerer J, et al., 2006) where it regulates digestion and maintains stomach function. Additionally, the remainder of serotonin is found in platelets and the central nervous system where serotonin is produced in the raphe nuclei and pineal gland of the brain (Neurophysiology Website).  Nerve axons from the raphe nuclei cover the entire length of the brainstem and extend to all parts of the brain including the cerebellum and spinal cord where serotonin influences memory, learning, behavior, mood (well-being, happiness), appetite, sleep and regulates insulin (Young SN, 2007).

When a sending neuron releases serotonin to stimulate a receiving neuron, the neurotransmitter travels out the sending neuron, across a gap or cleft to receptors on the receiving neuron.  By design the neurotransmitter is quickly reabsorbed back into the sending neuron and recycled.  A drug that modifies this normal physiology by keeping serotonin in this gap between the neurons longer is called a serotonin re-uptake inhibitor (SSRI). The result of a SSRI is to create the physiological impression that more serotonin is present thus continuing the stimulation of the receiving neuron. Many antidepressants, anti-anxiety drugs and post-traumatic stress drugs function in this manner.  These drugs do not produce more serotonin to resolve a deficiency, but create the illusion that more is present.

Should the body be deficient or low on serotonin, only ingesting the proper foods or supplementing the diet with tryptophan or 5-HTP provides more serotonin to the brain and intestines. Studies have shown that a change in only 10% of the number of serotonin transporters will affect anxiety levels (Lesch KP, et al., 1996).  Research shows that supplementing tryptophan or 5-HTP (available at nutritional stores) helps to maintain serotonin levels and aids with depression and anxiety (Murphy SE, et al., 2006).  Providing adequate nutrients is important to maintaining healthy cells and production pathways.




Phenylalanine  ———>  Tyrosine   ————>   DOPA     ————>   Dopamine

Dopamine  ——————–>   Norepinephrine  ———————–>  Epinephrine


The Phenylalanine to Tyrosine conversion requires Vitamin B9.

The Tyrosine to DOPA conversion requires Vitamin B9 and Iron.

The DOPA to Dopamine conversion requires Vitamin B3, Vitamin B6 and zinc.

The Dopamine to Norepinephrine conversion requires Vitamin C.

The Norepinephrine to Epinephrine conversion requires S-Adenylmathionine (SAMe)


This is a complicated pathway in that if  sufficient amounts of the amino acid phenylalanine or tyrosine, vitamin B9 (folate), iron, vitamins B3 (niacin) + B6 (pyridoxal phosphate), zinc, vitamin C (ascorbic acid), and methionine (used to produce SAMe) are all present, then the three catecholamine neurotransmitters in this pathway (dopamine, norepinephrine and epinephrine (adrenaline)) are produced to keep the pathway cells strong.  If production falls and pathway cells die off (apoptosis) Parkinson’s Disease or Altzheimer’s may develop.

Phenylalanine is found in fish, beef, chicken, milk, cheese, eggs, and nuts (

Tyrosine is found in beef, pork, turkey, duck, fish, egg whites, cheese, milk, and soy milk (

Methionine is essential amino acid required in the diet.  It is found in popcorn, grass fed meat, brown rice, organic oranges, and yogurt.  SAMe (s-adenylsylmethionine) is made from methionine.  It’s production is influenced by the neurotransmitter acetylcholine produced in the Acetylcholine Pathway described above.  Methionine is also found in wheat and can be a deficiency in a wheat free diet. Methionine controls the adrenal glands which are the first responders under stress conditions.  Stress may deplete methionine stores. Methionine chelates metals and neutralizes harmful chemicals.  Painters and those exposed to chemicals may require additional methionine to neutralize these chemicals. Methionine is critical for donating a methyl group (-CH3) to norepinephrine to produce epinephrine in the Dopamine Pathway giving the body energy.  Adrenals that are subjected to low levels of methionine may be a contributing factor to Adrenal Insufficiency, Tremor, and Parkinson’s Disease.

Vitamin B3, Vitamin B6, Vitamin B9.  B-complex vitamins are water soluble and must be ingested daily.

Foods highest in Vitamin B3 (niacin) can be found at

Foods highest in Vitamin B6 (pyridoxal phosphate) can be found at

Foods highest in Vitamin B9 (folate) are found at

Vitamin C  is water soluble and must be ingested daily.  Vitamin C food sources are listed at  Vitamin C is the major vitamin keeping the adrenal organs healthy.

Zinc is an important mineral.  There is an informative web site listing zinc foods at

Iron food sources are listed at

Dopamine is quickly degraded and excreted in the urine.  While there is some re-uptake, dopamine must be continually replenished.  Dopamine is produced in the adrenals, gastrointestinal tract, neurons, and brain generating either excitatory or inhibitory nerve impulses. It has important roles in reward and punishment brain activity, increased heart rate and blood pressure, sleep, mood, attention, working memory, learning, problem-solving, social behavior, cognition, voluntary movement, pain, and motivation.

Dopamine deficiency causes decline in memory, attention, problem-solving  and sociability.  Insufficient dopamine biosynthesis in the dopaminergic neurons can cause Parkinson’s Disease (Grace AA, 1984).  Stress increases the depletion of dopamine stores (Furuyashiki T, 2012).  Dopamine plays a role in pain processing (Viisanen H, et al., 2012 ),

Norepinephrine (noradrenaline) can be produced from tyrosine or phenylalanine in the presence of vitamin B9 (folate), iron, vitamin B3 (thiamine), vitamin B6 (pyridoxal phosphate), and zinc.  Norepinephrine is a neurotransmitter produced in the adrenal glands which helps control the body’s sympathetic system.  This system is responsible for the “fight or flight response” to danger (Guyton A, 2006). Norepinephrine is a stress hormone (Tanaka M, et al., 2000).  Its release increases heart rate, releases glucose from tissue, increases blood flow to skeletal muscle and brain oxygen levels.

Norepinephrine is important to prevent fainting (syncope) by preventing a drop in heart rate to maintain blood pressure.  Neurons project throughout the brain and spinal cord.

Norepinephrine has a role in behavior, motivation, attention, focus, decision making, learning,  motor output, response to performance error, negative feedback, monetary loss, cost benefit evaluation, task difficulty and the decision making process (Devauges V, et al., 1990) (Lutzenberger, W, et al., 1987) (Usher M, et al., 1999) (Eisenberger M, et al., 2003)(Falkenstein M, et al., 1991)(Genring WJ, et al., 1993) (Neurophysiologica 35), (Nieuwenhuis, S, et al., 2003). It has different actions upon different cell types.  Low levels of this neurotransmitter have a role in depression along with serotonin.

Norepinephrine is reabsorbed and degraded within seconds.  It works as an anti-inflammatory agent in brain tissue, suppressing cytokines.  In Alzheimer’s Disease the norepinephrine  producing cells may be affected (Szot P, et al., 2012).

Epinephrine (adrenaline) is an important component of the sympathetic fight or flight system.  Production of epinephrine occurs in the adrenals from phenylalanine and tyrosine.  It acts on most all body tissues.  Epinephrine increases blood glucose and fatty acid levels which provide energy for cells (Sabyasachi S, 2007).  Plasma levels of epinephrine may increase 10-fold during exercise and perhaps by 50-fold during stress requiring an ample supply of tyrosine (Raymondos, K, 2008) (Baselt, 2000).  Epinephrine is released during times of “physical threat, excitement, noise, bright lights, and high temperatures” (Nelson L, 2004). Stress causes the sympathetic nervous system to stimulate adrenocorticotrophic hormone (ACTH) which stimulates epinephrine release (by activating tyrosine hydroxylase and dopamine-B-hydroxylase).  It also stimulates cortisone production by the adrenals.

One study found that catecholamines (neurotransmitters derived from tyrosine in the dopamine pathway) in rat adrenals took  …FOUR  DAYS … yes,  FOUR  DAYS … to recover their original levels after being chemically depleted, and the regeneration of these neurotransmitters required acetylcholine (Patrick RL, et al., 1970).  A human taking a heavy examination may require several days to restore normal neurotransmitter levels, yet universities schedule mid-term and final exams on consequentive days allowing no time for neurotransmitter restoration.  When human adrenals are stressed they may take a significant amount of time and resources to regenerate neurotransmitters and cortisol. 

Tyrosine, vitamin B-complex, vitamin C, zinc, iron, and methionine or SAMe can be purchased at a health food store to supplement the diet and maintain a healthy dopamine pathway.

“Parkinson’s Disease is associated with the depletion of tyrosine hydroxylase, dopamine, serotonin, and norepinephrine” and “administration of L-dopa may deplete L-tyrosine, L-tryptophan and 5-hydroxytryptophan (5-HTP), serotonin and sulfur amino acids (cysteine, methionine)” (Hinz M, et al., 2011).  Researchers found that co-administration of L-dopa with 5-HTP, L-tyrosine, L-cysteine and cofactors enabled more effective treatment for Parkinson’s Disease by allowing optimal dosing of L-dopa for symptom relief without the barriers imposed by side effects and adverse reactions.  (Hinz M et al., 2011)



We have discussed three important pathways for producing neurotransmitters. The organs most responsible for this job are the adrenals.  The adrenals are critical to brain health. They are small, walnut shaped glands positioned on top of the kidneys.  Back pain can be felt below the rib cage on either side when the adrenals are over-stressed.  These organs produce neurotransmitters, sex hormones, and cortisol.  Under athletic, academic, work-related, emotional, food-related, disease or inflammation-related stress conditions, the adrenals are the first to respond by producing high amounts of cortisol.  The body tends to prioritize, so high cortisol production may come at the cost of reduced sex hormone and  neurotransmitter production.  We may see this in the triathlete with sporadic menses or the businessperson or student with high anxiety levels. The adrenals are prioritizing cortisol production to cope with the acute or chronic stress over the production of sex hormones and neurotransmitters

Upon the realization that these tiny organs are responsible for handling these vital functions, keeping the adrenals healthy becomes of critical importance.  We have described the three neurotransmitter pathways to reinforce the importance of providing the proper amino acids and vitamins to the body to keep these pathways alive and well. Cells die off when adequate nutrients are not present.  Vitamin C  and the amino acid methionine are important for general adrenal function. Methionine is found in wheat, so wheat free diets may be deficient in methioinine.  Glandular adrenal rebuilders are available at health food stores.  Sugar, high fructose corn syrup, alcohol, and deep fried food consumption stress out the adrenals and make them work hard.   There is an excellent book written by Dr. James Wilson, entitled “Adrenal Fatigue – The 21st Century Stress Syndrome”, (Smart Publications, 2001).  A future post will discuss adrenal insufficiency, methionine and a wheat free diet.  Restoring adrenal health and providing sufficient neurotransmitter substrate may be critical to restoring neurotransmitter supplies and eliminating disease.  More research should be completed and better monitoring of neurotransmitter nutrient pathways through physician and home based testing would be helpful.


Street Drugs, Nicotine, Caffeine, and Neurotransmitters:

The street drug cocaine is a triple re-uptake inhibitor in that it blocks the re-uptake of serotonin, dopamine and norepinephrine (Fattore L, et al., 2009 ).  Street drugs can increase dopamine levels 10 fold and temporarily cause psychosis (Williams).  Amphetamines are similar in structure to dopamine.   MDMA (ecstasy) releases serotonin, norepinephrine and dopamine and then inhibits their transport which increases concentrations within cell cytoplasm (Bogen IL, et al., 2003) (Fitzgerald JL, et al., 1990).

Amphetamines increase the concentrations of dopamine, serotonin and norepinephrine possibly by reversing the transport of dopamine and serotonin back into the gap or cleft between the neurons (Florin SM, 1994) (Jones S, et al., 1999). Dextromorphan, a cough suppressant, works as an SSRI (Schwartz AR, et al., 2008). LSD is a serotonin agonist in that it stimulates the serotonin receptor on the receiving neuron by mimicking serotonin (Titeler M, et al., 1988). Caffeine increases activity of serotonin, acetycholine, epinephrine, dopamine, and norepinephrine. Nicotine is thought to increase acetylcholine and dopamine levels.  Street drugs, caffeine, and nicotine force the body to release stores of neurotransmitters and then keep the neurotransmitter in circulation by inhibiting the reuptake.  Again, these drugs are not making more neurotransmitter but they are depleting current stores and tricking the body into thinking there is more chemical.  The only way to enable the body to produce more neurotransmitters is to provide the proper nutrients through diet or supplements.  


Analysis Unique to the Wheat Free Diet:

Many individuals damage their adrenals through alcohol, sugar, high fructose corn syrup, deep fried foods, low vitamin C and low nutrient intake causing depression, fatigue and eventually tremor.  The case above is unique, because this patient eats a healthy diet with the exception of wheat which contains the amino acids methionine and lysine.  Thus, her diet may be deficient in methionine.  However, shows detailed analysis that if she consumes meat, ample methionine should be present. Unlike earlier times, most cattle and fish are no longer raised in the wild.  Do they still contain adequate amino acids?  If this subject typically eats meat, containing several grams of amino acids per day, why would 500mg – 1g of supplemental methionine improve her condition?

Additionally, methionine is responsible for chelating harmful chemicals such as those found in paint. She may require additional methionine to detoxify the fumes.   This subject is highly stressed which would cause the adrenals to produce more cortisone. Regulation of the adrenal-pituitary-hypophyseal axis  requires methionine.  Perhaps a combination of low dietary intake plus a high methionine requirement resulted in damaging her adrenals and a reduction of neurotransmitter production.

Case Study References:

Livestrong website:

Headquarters Website:


Acetylcholine References:

Coplan JD, Hodulik S, Mathew SJ, Mao X, Hof PR, Gorman JM, Shungu DC. The Relationship between Intelligence and Anxiety: An Association with Subcortical White Matter Metabolism. Front Evol Neurosci. 2011;3:8. Epub 2012 Feb 1

De Simone R, Aloe L.  Influence of ethanol consumption on brain nerve growth factor and its target cells in developing and adult rodents. Source Istituto di Neurobiologia, Consiglio Nazionale delle Ricerche, Rome, Italy.  Ann Ist Super Sanita. 1993;29(1):179-83.

Glenn MJ, Adams RS, McClurg L. Source Department of Psychology, Colby College, 5550 Mayflower Hill Dr., Waterville, ME 04901, USA. Supplemental dietary choline during development exerts antidepressant-like effects in adult female rats. Brain Res. 2012 Mar 14;1443:52-63. Epub 2012 Jan 17.

Growdon JH, Gelenberg AJ, Doller J, Hirsch MJ, Wurtman RJ. Lecithin can suppress tardive dyskinesia. PMID: 642995 [PubMed – indexed for MEDLINE]. N Engl J Med. 1978 May 4;298(18):1029-30.

Guttierez-Fernández M, Rodríguez-Frutos B, Fuentes B, Vallejo-Cremades MT, Alvarez-Grech J, Expósito-Alcaide M, Díez-Tejedor E. Source Neuroscience and Cerebrovascular Research Laboratory, La Paz University Hospital, Neurosciences Area of IdiPAZ, Health Research Institute, Autónoma University of Madrid, Madrid, Spain. CDP-choline treatment induces brain plasticity markers expression in experimental animal stroke. Neurochem Int. 2012 Feb;60(3):310-7. Epub 2011 Dec 30.

Hasler CM (October 2000). “The changing face of functional foods”. Journal of the American College of Nutrition 19 (5 Suppl): 499S–506S. PMID 11022999.

Hirsch MJ, Wurtman RJ. Lecithin consumption increases acetylcholine concentrations in rat brain and adrenal gland. Science. 1978 Oct 13;202(4364):223-5.

Institute of Medicine, Food and Nutrition Board. Dietary reference intakes for Thiamine, Riboflavin, Niacin, Bitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin and Choline. Washington, DC: National Academies Press;1998

Johnson AR, Lao S, Wang T, Galanko JA, Zeisel SH.  Source Department of Nutrition, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.  Choline dehydrogenase polymorphism rs12676 is a functional variation and is associated with changes in human sperm cell function.PLoS One. 2012;7(4):e36047. Epub 2012 Apr 27.

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Sha W, da Costa KA, Fischer LM, Milburn MV, Lawton KA, Berger A, Jia W, Zeisel SH.Source Bioinformatics Research Center, University of North Carolina at Charlotte, USA.Metabolomic profiling can predict which humans will develop liver dysfunction when deprived of dietary choline. FASEB J. 2010 Aug;24(8):2962-75. Epub 2010 Apr 6.

Xu X, Gammon MD, Zeisel SH, Bradshaw PT, Wetmur JG, Teitelbaum SL, Neugut AI, Santella RM, Chen J.  Source  Department of Community and Preventive Medicine, Box 1057, Mt. Sinai School of Medicine, One Gustave L. Levy Place, New York, NY 10029, USA. High intakes of choline and betaine reduce breast cancer mortality in a population-based study.  FASEB J. 2009 Nov;23(11):4022-8. Epub 2009 Jul 27.

Zeisel SH, da Costa KA. Source  Department of Nutrition at the Nutrition Research Institute, School of Public Health and School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA.  Nutr Rev. Choline: an essential nutrient for public health. 2009 Nov;67(11):615-23.

Zhang W, Bai M, Xi Y, Hao J, Liu L, Mao N, Su C, Miao J, Li Z. Early memory deficits precede plaque deposition in APPswe/PS1dE9 mice: involvement of oxidative stress and cholinergic dysfunction. Source Department of Neurology, Tangdu Hospital, Fourth Military Medical University, Xi’an City, Shaanxi Province 710038, China. Free Radic Biol Med. 2012 Apr 15;52(8):1443-52. Epub 2012 Feb 2.

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Serotonin References:
Bogen IL, Haug KH, Myhre O, Fonnum F (2003). “Short- and long-term effects of MDMA (“ecstasy”) on synaptosomal and vesicular uptake of neurotransmitters in vitro and ex vivo”. Neurochemistry International 43 (4–5): 393–400. doi:10.1016/S0197-0186(03)00027-5. PMID 12742084.
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Street Drugs, Nicotine, Caffeine, Alcohol and Neurotransmitters:

Bogen IL, Haug KH, Myhre O, Fonnum F (2003). “Short- and long-term effects of MDMA (“ecstasy”) on synaptosomal and vesicular uptake of neurotransmitters in vitro and ex vivo”. Neurochemistry International 43 (4–5): 393–400. doi:10.1016/S0197-0186(03)00027-5. PMID 12742084.

Fattore L, Piras G, Corda MG, Giorgi O (2009). “The Roman high- and low-avoidance rat lines differ in the acquisition, maintenance, extinction, and reinstatement of intravenous cocaine self-administration”. Neuropsychopharmacology 34 (5): 1091–101. doi:10.1038/npp.2008.43. PMID 18418365.

Fitzgerald JL, Reid JJ (1990). “Effects of methylenedioxymethamphetamine on the release of monoamines from rat brain slices”. European Journal of Pharmacology 191 (2): 217–20. doi:10.1016/0014-2999(90)94150-V. PMID 1982265.

Florin SM, Kuczenski R, Segal DS (August 1994). “Regional extracellular norepinephrine responses to amphetamine and cocaine and effects of clonidine pretreatment”. Brain Res. 654 (1): 53–62. doi:10.1016/0006-8993(94)91570-9. PMID 7982098.

Jones S, Kauer JA (November 1999). “Amphetamine depresses excitatory synaptic transmission via serotonin receptors in the ventral tegmental area”. J. Neurosci. 19 (22): 9780–7. PMID 10559387.

Schwartz AR, Pizon AF, Brooks DE (September 2008). “Dextromethorphan-induced serotonin syndrome”. Clinical Toxicology (Philadelphia, Pa.) 46 (8): 771–3. PMID 19238739.

Titeler M, Lyon RA, Glennon RA (1988). “Radioligand binding evidence implicates the brain 5-HT2 receptor as a site of action for LSD and phenylisopropylamine hallucinogens”. Psychopharmacology (Berl.) 94 (2): 213–6. PMID 3127847.


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Photograph: Jordanelle Reservoir, Park City, Utah

A Special Thanks to Billie Jay Sahley PhD. and her books on amino acids including her book “The Anxiety Epidemic” for inspiring research with neurotransmitter pathways, substrates and cofactors.

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