Low Serotonin Theories

[Please read the disclaimer for this journal before jumping in - I am a student and do not diagnose or treat symptoms.  This paper is for an introductory psychopathology class.  Please be kind and do not steal my work (though I encourage those interested to look up the references)]

Low Serotonin Theories

Introduction

Modern psychiatry understands an element of depression to be a deficit in the neurotransmitter serotonin.  As society, medicine, and therapy advance, there seems to be a shift from simply treating symptoms.  Instead, society and the scientific community seek to understand the underlying causes of their illness, which begs the question:  if a person is depressed because of low serotonin, what is causing it to be low to begin with?  There are several theories on the subject, and it is possible that most of them are correct – at least for some people.  As the search for causes presses on, there is increased awareness that a one-size-fits-all model of cause and treatment is, at best, incomplete.  Still, the theories presented are shaping the worlds understanding of depression and other symptoms that arise from low serotonin.  The following is only a handful out of a potentially infinite number of theories.

The Genetic Theory

            There is no doubt that genes play a role in who we are.  According to Comer, family pedigree and twin studies have revealed that genetically related individuals have higher rates of depression than the general population, suggesting a fairly strong genetic component.  In both family pedigree studies and DZ twin studies, rates of depression were at about twenty percent, versus less than ten percent for the general population (Comer, 2008).  In identical twin studies, the rate was much more significant – MZ twins showed that 46 percent of the time, if one twin suffered depression, so did the other (Comer, 2008).

It is suggested that the gene SLC6A4 (alternatively referred to at 5-HTT or Serotonin Transporter) plays a role in uptake rates of serotonin.  According to the NCBI website on the human genome project:

This gene encodes an integral membrane protein that transports the neurotransmitter serotonin from synaptic spaces into presynaptic neurons. … A repeat length polymorphism in the promoter of this gene has been shown to affect the rate of serotonin uptake and may play a role in sudden infant death syndrome, aggressive behavior in Alzheimer disease patients, and depression-susceptibility in people experiencing emotional trauma (SlC6A4 solute carrier family 6, 2010).

That is to say, mutation of this gene doesn’t necessarily cause low levels of serotonin but mutations in it may cause alterations in the rate of synapse and reuptake, which in turn, may affect the emotional well being and health of the individual.

The Amino Acid Theory

            According to Natural Doctors Michael Murray and Joseph Pizzorno, tryptophan, an amino acid found in the human diet, is essential for healthy levels of serotonin (1998).  In experimental studies where subjects are fed diets devoid of tryptophan, it is noted that depression is a common result or effect among test subjects.  Still, this is not the entire story.  According to Murray and Pizzorno (1998):

Supplementation with tryptophan in depressed individuals has produced mixed results in the published clinical trials.  In only two out of eight studies that compared tryptophan to a placebo was tryptophan shown to be more effective than the placebo. … A number of factors, such as hormones (estrogen and cortisol) and tryptophan itself, stimulate the activity of tryptophan oxygenase, which results in tryptophan being converted to kynurenine and less tryptophan being delivered to the brain (p. 380).

Once tryptophan is consumed, an enzyme in the body converts tryptophan into 5-HTP (5-Hydroxytryptophan), a precursor to serotonin and melatonin (perhaps this also explains insomnia in some depressed patients).  It is also suggested that some people lack the enzyme that converts tryptophan into 5-HTP.   According to Murray and Pizzorno (1998):

Unlike tryptophan, 5-HTP cannot be converted into kynurenine … As a result, while only three percent of an oral dose of tryptophan is converted into serotonin, over 70 percent of an oral dose of 5-HTP is converted to serotonin.  … Numerous double blind studies have shown that 5-HTP has equal effectiveness compared to drugs like Prozac, Paxil, and Zoloft (the selective serotonin reuptake inhibitors, SSRIs) and tricyclic antidepressant drugs… (p. 380, 390-393, 686-687).

In addition, the decreased conversion of tryptophan into 5-HTP has been linked to obesity, lack of satiety, (Murray et al., 1998) and difficulties with sleep cycles (Murray et al., 1998), all of which are reported to be symptoms linked with depression.

The Hormonal Theory

            There are two hormones suspected to affect serotonin levels:  cortisol and estrogen. Cortisol is a hormone released by the adrenal glands in times of stress. Comer (2008) writes:

People with unipolar depression have been found to have abnormal levels of cortisol; one of the hormones released by the adrenal glands during times of stress … This relationship is not all that surprising, given that stressful events often seem to trigger depression (p. 193).

Murray and Pizzorno (1998) argue that perhaps it is not necessarily the stressful event that triggers depression, but the hormone cortisol that is released by the adrenal glands in times of stress:

When the adrenal gland releases increased amounts of natural cortisol, its effects on  brain mirror the side effects of synthetic cortisones such as prednisone:  depression, mania, nervousness, insomnia, and, at high levels, schizophrenia.  The effects of cortisol on mood are related to its activation of tryptophan oxygenase … results in shunting of tryptophan to the kyneurenine pathway at the expense of serotonin and melatonin synthesis (p. 383).

As previously discussed, tryptophan is a part of the human diet, essential in the production of serotonin.  If the body converts tryptophan into kyneurenine instead of 5-HTP, serotonin cannot be produced.

            Another hormone linked to serotonin production is estrogen.  According to Sandhya Pruthi, M.D. on the Mayo Clinic website, PMS (premenstrual syndrome) and PMDD (premenstrual dysphoric disorder) are characterized by bouts of depression or sadness (Premenstrual Syndrome, June 21, 2008).  According to Comer (2008):

…Other biological researchers are beginning to suspect that unipolar depression is tied more closely to what happens between neurons …. They believe that abnormal activity by key neurotransmitters or hormones ultimately leads to deficiencies of important proteins and other chemicals within neurons – deficiencies that impair the health of the neurons and lead, in turn, to depression (p. 193).

Murray and Pizzorno (1998) take note of a link between female sex hormones and depression:

It is interesting to note that the majority of the over twelve million patients who take Prozac are women between the ages of twenty-five and fifty – the same population that has a high frequency of PMS (p. 737).

Murray and Pizzorno (1998) expand on these ideas by discussing the effects of abnormal estrogen levels on neurotransmitters.  They suggest that estrogen excess impairs synthesis of neurotransmitters, including serotonin (732).  Increased levels of estrogen can prevent the amino acid tryptophan from reaching the brain in the form of 5-HTP.

Conclusion

            These are but a few of the theories for low serotonin levels seen in many patients suffering from depression.  Each theory seems that it can build upon another – although the discussed gene (one of potentially several that plays a role in serotonin levels) does not appear to be inherently related to either the amino acid or hormonal theories, it is likely that genes influence enzyme and hormonal activity, which in turn, affects serotonin production.  Furthermore, the amino acid theory is enhanced by the hormonal theory – if the proper amino acids are not properly converted and able to reach the brain, hormones might be a potential cause. 

One thing is for certain – the search for causes will be an extensive one.  At each new level of understanding, we have to ask, “What is causing the malfunction?”  For the theories given, we could arguably state, “low serotonin levels in case A are caused by a lack of tryptophan from reaching the brain, which is caused by increased cortisol secretion … which is caused by these genetic factors.”  It seems that with theories for low serotonin, each answer brings about a new round of questions – this is the beauty and frustration that is science.

References

Comer, R. J. (2008). Fundamentals of Abnormal Psychology. New York, NY: Worth Publishers.

   Murray, M. T., N.D., & Pizzorno, J. E., N.D. (1998). Depression. In Encyclopedia of Natural Medicine (Vol. 2, Rev., pp. 380-393, 686-687, 732-737). Roseville, CA: Prima Publishing.

   SLC6A4 Solute Carrier Family 6. (2010). Retrieved April 04, 2010 from National Center for Biotechnology Information: http://www.ncbi.nlm.nih.gov/​gene/​6532?ordinalpos=1&itool=entrezsystem2.pentrez.gene.gene_resultspanel.gene_rvdocsum.

   Pruthi, S., M.D. (2008). Premenstrual Syndrome (PMS). Retrieved April 05, 2010 from Mayo Clinic Online: http://www.mayoclinic.com/​health/​pmdd/​an01372.

The mind-body disconnect - part two.

An alternative route of speculation, and a far less sensitive one, is to further examine the mind-body disconnect in women.  The fact that women are not consciously in sync with their physical arousal may leave room to question this weakness in relation to depression, eating disorders, and other diet/exercise related issues.

A quick lesson in emotion:  emotion is a part of our autonomic nervous system, part of our peripheral nervous system, which is wired through our limbic system.  You know how a hug can make you feel really happy?  That's the peripheral nervous system at work.  That's the mind-body connection.  When you get sick and maybe experience irritability, again, that's the mind-body connection.  Simply put, when our bodies feel bad, our minds feel bad, and vice versa.  So what happens when that link is fuzzy?

I'm going to use the example of diet soda, and also use an anecdote to make a point (I can hear my Psych professors weeping now).  Diet soda, in essence, is one of the worst things you can put in your body.  More specifically, the aspartame found in diet soda is one of the worst things you can put in your body.  Essentially, there are elements of aspartame that your body cannot properly break down and dispose of.  One specifically to focus on is methyl alcohol.  When put into your body, methyl alcohol becomes formaldehyde and rests as a toxin within your body.  Toxin, or poison, obviously is not a good thing to have inside your body and is apt to make it feel bad.  Victims of aspartame poisoning report a wide range of symptoms, some of which have been diagnosed as MS, brain tumors, etc.  Several people who have gone through detoxification have seen a reduction in symptoms, sometimes even in tumor size.  For more information, seek out a documentary called "Sweet Misery."  There is information within the documentary for further resources if you are interested.

So, back to the point.  In all essence, aspartame is pretty bad stuff and is bound to make your body feel bad. As we know, when your body feels bad, so does your brain.  Cue my anecdote.  I watch my sister suck down bottles of diet soda a day (and this doesn't include other diet foods she's eating, which may contain dangerous chemicals as well).  At the same time, I hear her talking about her continuing struggle with depression and a need to increase or change her medication.  I cannot help but wonder if my sister is a victim of mind-body disconnect.  I can't imagine that her body is fairing well after years of drinking diet soda, and yet she is focused solely on what is going on with her mind.  I try to encourage her to really pay attention to how she feels after she eats or drinks anything, but judging from her medicine cabinet, headaches and the like are annoying yet trivial aspects of life that she is not willing to invest much time in - aside from picking up an extra large bottle of ibuprofen whenever she goes to Costco.

It's no secret that depression affects women disproportionately, and I wonder if that has anything to do with possible disconnection.  Women live in a society where thin is in for them, and I have to wonder how many women shop specifically for a diet fad, and how many of them are suffering the consequences.  Any processed food is bound to have a negative impact on the body - we humans are neither processed nor genetically modified, so I am curious as to why we are expected to eat these things.  

Furthermore, we live in a society where we are becoming less and less active with each generation.  We are eager to say we are tired because we are depressed or depressed because we're tired.  We're also quick to blame the world - work weeks that are too long, a failing economy.  Our reasoning is more of a cycle of illogic.  If we're tired and depressed, it's likely that we've spent too many nights loafing on the couch.  If we're stressed about work or the world, we might seek solace in television and comfort food, even though we should be choosing a treadmill.  I imagine that if we took a look at the numbers, we'd find men sweating out their stress more than women.  More than that, I know we'd find more women with unhealthy relationships with food - whether it be eating too much or too little or throwing it up.  I'd argue that there's more than a casual arrow between depression and eating disorders.  I think it would be possible to hypothesize that at the very least, the eating disorder acts as a catalyst for the depression, especially as the body starts to really break down.

I'll end here - tonight has been productive for my my mind, but again, it is all in speculation.  As always, this journal comes with a disclaimer.  That is, I'm not a professional, I'm a student.  This is a place for me to share concepts I find interesting and sort through some of my own ideas on topics.  If I make any exceptional points in class or on a paper, I'll be sure to share.  Still, I'm not a doctor or licensed professional.  I cannot counsel you, recommend you change your medication, or give you the green light to start a diet and exercise routine.  Your doctor can talk about these things with you.  All I can do is provide food for thought, and maybe offer you some topics to bring up to your doctor or therapist.


If I have it in me, I'll try to expand on that article some more later.  There were so many elements of it, and so many things to say about each one.  I have a lot to say about Diamond's research.  Although lacking in external validity (she didn't include heterosexual women in her studies), her topic is fascinating and one I'd like to explore.  Rape fantasies and desire vs. power and narcissism, and how that might relate to the loss of sexual desire a woman may feel in long term relationships.  Not to mention buffering her statements from claims of misogynistic undertones in her theories.  Really, read the article again and think.  It's not as sexist as it sounds.

Female sexuality: the mind body disconnect - pt. 1

Article:  http://www.nytimes.com/2009/01/25/magazine/25desire-t.html

Note:  This entry is a response to theories posted in the article.  Nothing written here has been scientifically validated.  The purpose here is to open the stream of consciousness and perhaps raise possible hypotheses that can be tested, or at least encourage a look into correlational studies.

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This article discusses several research projects done by sexologists in an attempt to answer what Freud could not.  What do women want?

Chivers' research seems to suggest that there is a mind-body disconnect with women, at least in the realm of their sexuality.  She is not the only scientist seeing this phenomenon.  Women are capable of physical (objective) sexual responses without conscious awareness of desire or arousal.  Evolutionary theory would see this as adaptive.  Women have faced sexual violence throughout history, particularly rape.  It is suggested that women evolved to have physical arousal without conscious awareness of want as a defense to these unwanted advances - a physical response provides her body protection from tearing and infection.

Moreover, it may be possible to hypothesize that the mind-body disconnect in women serve an adaptive purpose for the psyche as well.  Physical assault, while horrifically traumatizing, may produce more serious psychological damage is woman had the same strong mind-body (objective-subjective) connection that their male counterparts do.  That is, women may hold the capacity to defend their psyche by disconnecting their subjective experience from what their body is going through (the objective experience).  This may produce inability to recall certain details, entire parts, or perhaps even the majority of the assault itself.  When a womans conscious is separated from what is happening to her body, she may later in subsequent therapy be able to separate herself from the experience; her body has been victimized, but she does not have to be a victim.

I discussed this topic with a friend of mine who has her MA in Psychology.  She had suggested that there may be additional consequences of this mind body disconnect.  She expressed interest in seeing if there are any possible links between this disconnect and certain mental disorders, specifically Disassociative Identity Disorder, or DID (formerly multiple personality disorder).  DID more prevalent in women than men, and the number of patients meeting the criteria is swiftly rising.  Although controversial for a number of reasons, it may not be all that unreasonable to speculate that DID can arise as an individual response to sexual trauma.  The characteristics of DID, in a way, offer another degree of separation from the experience.  For those who are unable to resolve psychological issues related to sexual trauma or for those who feel subjectively victimized, an "alter ego" so to speak may offer their conscious a break from a world where they feel like a victim.

This is, of course, entirely speculation.  The amount of testing that would have to go into a research project like this far outweighs this authors abilities at this time.  First, correlational studies would have to be performed to even see if there is a link between DID patients and any history of sexual violence.  The problem with this is the controversy that comes from each of these, particularly surrounding the therapist.  There have been several incidences in history where therapists have brought out problems in patients, such as DID or a history of sexual assault when neither existed in the first place.  Doing a correlational study would be a delicate task, and would need to be done by some very careful, intelligent researchers.  Furthermore, if a study like this made it into the experimental phase, some very large ethical issues may arise.  I'd imagine at one point in a study like this, it would be important to measure the objective and subjective sexual responses of rape victims, but doing so much as connecting the patient to a plethysmograph may prove to be detrimental to the patient's psychological well being.  Beyond that, obtaining consent for such a study may prove to be a very difficult manner.

(TBC)

Course hopping. Weather forecasting.

At the very last minute, I changed my course load for the quarter.  I dropped counseling to take Native American Psych Values.  Counseling will happen again.  I told myself that whatever I had to do, I'd take the NAPV course the first chance I got.  It's a selected topics course, meaning its one of several Psych 410 courses.  Funny thing is, my other course, human sexuality, is also a Psy 410 course.  My DARS audit is showing that these indeed will count as separate courses.

This class looks like it will be a challenge to my last quarter of classes.  Much less based in science, more in sociology.  The instuctor is also a heavy believer in concepts that lie outside of science - generations of wisdom passed down, before a world where we are told what we can and cannot take as truth.  I like the contrast.

I'm not sure what my drive is behind this decision.  I think that part of it is that I feel like I better identify with a traditional (native) culture more than the reigning one.  It's easier for me to give thanks to plants and animals and see them as part of a collective conscious than it is to pray to some invisible man in the sky.  It is easier for me to recognize time as cyclical and to make changes based on that recognition - instead of waiting for some event to fall into my lap, I know it is up to me to make something extraordinary out of each day.

With that, I'll leave you with a fabulous story told by my instructor today.

A farmer is gearing up for winter, collecting and stacking hay for his animals.  He wants to know how prepared he should be, so he asks around and is directed to speak to an old native man that lives on top of a hill.  The farmer goes up, and asks the native, "how bad is the winter going to be?"  The native looks around, out the windows, and sighs, "it's going to be a pretty rough winter."

The farmer thanks him and promptly runs back to his farm and begins stacking more hay.  He is not sure he has enough, so he returns again to inquire about the upcoming winter.  "I need to know, how bad will this winter be?"  Again, the native takes a moment to look outside.  "It's going to be pretty terrible."

The farmer returns to his farm and stacks as much hay as he can fit.  Still worried, he decides to go one more time and ask the native about the winter.  "Are you sure this is going to be a rough winter?"  The native again looks outside.  "Oh, yes, the worst one yet."  The farmer is amazed.  "How do you know all this?"  The native simply responds, "Well, I look down there at that farm and count the stacks of hay - the more bales of hay, the worse the weather.  The farmer that lives there has been creating a large stockpile over the past few days, so I think it will be a very difficult winter."

Enlightenment Effect.

In psychology, the enlightment effect refers to the idea that public knowledge about psychological research can change the world in a positive way.  For example, if people were more aware of bystander non intervention (bystander effect), we would expect to see an increase in help being offered in an emergency situation, even when a group is present. 

My goal with this journal is to give readers a general look into psychological theories that I find beneficial and interesting as I work towards my degree. This will also be combined with thoughts and opinions on certain topics.  Please read the disclaimer and note that any and all content here is not to be taken as a replacement for professional help.

There are some ideas that I may form an opinion or hypothesis about, and have to edit later as new information comes along.  This is the nature of education.  It is also the nature of science.  On my first day of class, I was informed that most of what I learn will probably be irrelivant in several years, as better theories are formed through careful experimentation.  The trick is to keep an open mind.

There are also several aspects of the world that fall outside the limits of science.  Whereas we have not yet designed sound studies to prove or disprove the existence of God, a soul, ESP, or any other supernatural phenomenon, we can design correlational studies to see if there is any association between belief in certain supernatual phenomenon and traits.

There are also a lot of experiments that have been done that will need to be improved on throughout the years, as better equipment and research designs become available.  As of right now, I am not properly trained for sound experimental design, thus, many of the topics I will discuss will be backed up by research already done by others.  Any opinions or hypotheses I may form are a long way from being tested by me, but I will do my best to keep a plausible scientific explanation in mind, include research that may serve to both support and refute my opinion, and be prepared to be proven wrong.

DISCLAIMER - Please read first!!!!!

The content in this journal is NOT a replacement for professional psychological or psychiatric help. 

Please talk to a professional before making any changes in your psychiatric treatment. 

The author of this journal is a psychology STUDENT, not a licensed professional.  This journal is serving as a creative outlet as the author journeys through school.  Again, author is NOT a licensed professional and any thoughts or opinions stated in this journal are not meant to be a replacement for professional help. 

ALWAYS speak with your doctor or a licensed professional before altering your mental health routine (ie: diet, exercise, and/or medication, etc), as not doing so could be potentially dangerous to your health.