Serotonin and the Link to Mood Disorders

Serotonin is a monoamine neurotransmitter that assists in the regulation of mood, sleep, muscle contractions, appetite, etc. Below is a diagram of brain that shows the different serotonin pathways.
In the past couple of years, studies have shown there to be a link between serotonin deficiency and depression.
The following excerpt is taken from the article, Serotonin: From Bliss to Despair by Joseph M. Carver, Ph.D.

"Perhaps the best way to think of Serotonin is again with an automobile example. Most automobiles in the United States are made to cruise at 70 miles per hour, perfect for interstate highways and that summer vacation. If we place that same automobile on a racetrack and drive day-after-day at 130 mph, two things would happen. Parts would fail and we would run the engine so hot as to evaporate or burnout the oil. Serotonin is the brain’s “oil”.

Like a normal automobile on a race track, when we find ourselves living in a high stress situation for a prolonged period of time, we use more Serotonin than is normally replaced. Imagine a list of your pressures, responsibilities, difficulties and environmental issues (difficult job, bad marriage, poor housing, rough neighborhood, etc.). Prolonged exposure to such a high level of stress gradually lowers our Serotonin level. As we continue to “hang on” we develop symptoms of a severe stress-produced depression.

An automobile can be one, two or three quarts low in oil. Using the automobile as an example, imagine that brain Serotonin can have similar stages, being low (one quart low), moderately low (two quarts low), and severely low (three quarts low). The less Serotonin available in the brain, the more severe our depression and related symptoms.

When Serotonin is low, we experience problems with concentration and attention. We become scatterbrained and poorly organized. Routine responsibilities now seem overwhelming. It takes longer to do things because of poor planning. We lose our car keys and put odd things in the refrigerator. We call people and forget why we called or go to the grocery and forget what we needed. We tell people the same thing two or three times.

As stress continues and our Serotonin level continues to drop, we become more depressed. At this point, moderately low or “two quarts” low, major changes occur in those bodily functions regulated by Serotonin. When Serotonin is moderately low, we have the following symptoms and behaviors:

· Chronic fatigue. Despite sleeping extra hours and naps, we remain tired. There is a sense of being “worn out”

· Sleep disturbance, typically we can’t go to sleep at night as our mind/thought is racing. Patients describe this as “My mind won’t shut up!” Early-morning awakening is also common, typically at 4:00 am, at which point returning to sleep is difficult, again due to the racing thoughts.

· Appetite disturbance is present, usually in two types. We experience a loss of appetite and subsequent weight loss or a craving for sweets and carbohydrates when the brain is trying to make more Serotonin.

· Total loss of sexual interest is present. In fact, there is loss of interest in everything, including those activities and interests that have been enjoyed in the past.

· Social withdrawal is common – not answering the phone, rarely leaving the house/apartment, we stop calling friends and family, and we withdraw from social events.

· Emotional sadness and frequent crying spells are common.

· Self-esteem and self-confidence are low.

· Body sensations, due to Serotonin’s role as a body regulator, include hot flushes and temperature changes, headaches, and stomach distress.

· Loss of personality – a sense that our sense of humor has left and our personality has changed.

· We begin to take everything very personally. Comments, glances, and situations are viewed personally and negatively. If someone speaks to you, it irritates you. If they don’t speak, you become angry and feel ignored.

· Your family will have the sense that you have “faded away”. You talk less, smile less, and sit for hours without noticing anyone.

· Your behavior becomes odd. Family members may find you sitting in the dark in the kitchen at 4:00 am.

Individuals can live many years moderately depressed. They develop compensations for the sleep and other symptoms, using sleeping medication or alcohol to get some sleep. While chronically unhappy and pessimistic, they explain their situation with “It’s just my life!” They may not fully recognize the depressive component."

The Female Brain

Louann Brizendine, M.D. is a neuroscientist with degrees from Berkley and Yale. She completed her training at Harvard Medical School and has taught there, as well as at UC San Francisco. She founded the Women’s Mood and Hormone Clinic in 1994, is an active clinician and a research scientist. Her book “The Female Brain” has been translated into 26 languages and was a New York Times bestseller.

Dr. Brizendine’s book brings the public an insight into her research about how the female brain differs from its male counterpart. It is a fascinating journey, explaining the female brain from conception until death.

Below are some items learned from reading “The Female Brain.”

· The brain of a fetus is female until 8 weeks into gestation, when large levels of testosterone are released into the brain and bloodstream.

· According to Brizendine’s interpretation of clinical studies, female infants seem to be more primed for communication, typically gazing more at their caregiver’s facial expressions and paying more attention to their utterances.

· The female brain appears to have more connections between left and right hemispheres, and a greater number of cells devoted to perceiving and processing language.

· Post-pregnancy, the female brain shrinks by 8 percent, returning to its original size within a year.

Clearly, Dr. Brizendine is eminently qualified and incredibly knowledgeable about her field. It is difficult to write a book targeted towards a general audience, because levels of understanding among the public can vary widely. This is perhaps one reason why some of the material was deemed “controversial” by the media. The book contains a lot of basic scientific information about hormones, presented clearly with engaging case-study examples.

Dr. Brizendine has also just published “The Male Brain,” which looks to be a fascinating read!

Neurological Disorders

One major part of neuroscience is neurology, a medical discipline that deals with disorders of the nervous system. This is a very broad field that deals with over six hundred different diseases. Rather than boring you, though, with a list of all six hundred of these, a better idea would seem to be a more simple explanation of some of the more major and common neurological disorders:

• Multiple sclerosis occurs when damage to neurons' myelin sheaths causes interference with the messages the neurons are supposed to be passing along. When this happens, the most common symptoms are visual disturbances, physical weakness, trouble with coordination and balance, problems with thinking and memory and feelings such as numbness and prickling. At present the cause of this neuron damage is unknown and there is no cure, although there is treatment available to help with the symptoms.
• Alzheimer's disease is a common form of dementia among older people. There is currently no cure and treatments for this disease are relatively limited and ineffective. This means that people with Alzheimer's invariably develop progressively worse memories that eventually cause them to forget family members and even leave them incapable of performing normal daily activities such as combing their hair or brushing their teeth. People in the later stages of the disease can become anxious or aggressive and will eventually require total care.
• Parkinson's disease occurs when the neurons responsible for producing dopamine fail to do this. This lack of dopamine leads to trembling and stiffness throughout the body, slow movement and poor balance and coordination. This disease can even indirectly lead to further problems as the symptoms themselves can cause depression and trouble sleeping, chewing, swallowing and speaking. Fortunately, although there is no cure, treatments are often very effective at taking care of the symptoms.
• Epilepsy takes place when clusters of neurons send out the wrong signals, leading to recurring seizures. Epilepsy can be caused by illnesses, brain injuries and abnormal brain development. No cure has been found for this disease, but treatments have proven effective at controlling the seizures.
• Brain tumors can be either malignant or benign, meaning they can occur with or without cancer cells. Unfortunately, no one is quite sure what causes either form of tumor. What is certain though is the fact both kinds of brain tumors most often result in headaches, nausea, vomiting, changes in the victims' abilities to talk, hear or see, problems with balance, walking, thinking or memory, muscle jerking or twitching and numbness or a tingling feeling in the limbs.
• Strokes result from a stop in blood flow to the brain, which is most often caused by a blood clot or break in a blood vessel. Symptoms of a stroke appear suddenly, and they can do very serious damage to a person unless help is received immediately. Strokes can be recognized by weakness or numbness in one side of the face or limbs, confusion, trouble speaking, understanding speech, seeing or walking, problems with balance or coordination, dizziness and severe headaches. There is also a more minor form of a stroke, known as transient ischemic attack, that is caused by a brief interruption in the flow of blood to the brain.
• In spinal cord injuries, there are two possible outcomes which are entirely dependent on the severity of the damage caused to the spinal cord. If the damage wasn't very sever, then there will only be sensations or movement problems below the site of the original injury, but more severe damage prevents the spine from relaying information below the point of this injury, resulting in paralyzation below the injury. However, swift treatment can reduce the long-term effects of spinal cord injuries.
• Concussions are the most minor form of brain injury. They are short losses of normal brain functions and can cause head or neck pain, nausea, ringing in the ears, dizziness, exhaustion, feeling dazed and a feeling that victims aren't themselves. In most cases, these conditions are light enough to not require medical attention.
• Brain aneurysms result from abnormal bulges in the walls of arteries in the brain. Symptoms often don't develop until the bulge becomes very large, leaks blood or ruptures. Regardless of the cause, brain aneurysms can cause droopy eyelids, double vision or other vision changes, pain above or behind the eyes, dilated pupils and numbness or weakness on one side of the body, but a ruptured artery can also lead to sudden, severe headaches, nausea, vomiting, stiffness in the neck, loss of consciousness and signs of a stroke. Because of this variation in symptoms, treatments also depend on the size and location of the bulge and whether it has become infected or ruptured.

All of the above information was taken from Medline Plus and MedicineNet.com.

As your looking at this blog, I'm sure your wondering about career options and training in this field of psychology. One option is becoming a Neuroscientist. A Neuroscientist studies the nervous system, including the neural basis of behavior, neuron, actions at the synapse, neurotransmitters and other various components of the nervous system and behavior. There are many specializations a Neuroscientist can go into. The examples are listed below.

1)A Neuropathologist (M.D. or Ph. D.)studies diseases of the nervous system.
2)Neuropharmacologists study the effects of medicines on the nervous system or behavior.
3)Neurophysiologists study the physiology of the nervous system.
4)A Neuropsychologist study the relationship between brain and behavior.
5)A specialized nurse in Neuroscience cares for patients with neurological disorders.
6)Developmental neuroscientists study brain growth and change.
7)Behavioral and cognitive neuroscientists study functions such as perception, learning, and memory in animals.
8)Clinical neuroscientists research current knowledge of neuroscience to prevent or treat neurological disorders. These specialists include psychiatrists and neurologists.
9)An electro-neuro-diagnostic technician records electrical activity from the brain and spinal cord.

COGNITIVE NEUROSCIENCE!!

Today, I took part in a study for Dr. Gianna Grossi, a member of faculty here at New Paltz University. I am not at liberty to discuss details of the experiment (protocol, so that other participants don't find out, which could affect the process of data collection.) I can, however write a little about the field of psychology that Dr. Grossi is working in.

COGNITIVE NEUROSCIENCE:

Cognitive Neuroscience --Then and Now

Cognitive Neuroscience is the study of how the brain "thinks". Far from being a new field, this field of investigation has existed since the early 19th Century. The above left image, of a "phrenology" head illustrates the early "scientific" attempts to formulate ideas and theories about thought and behaviour. Initially, it was believed that the topology of the skull (its lumps and bumps) had to do with cognition. Luckily, a number of 19th Century physicians and scientists challenged the views of phrenology, carrying out experiments on animal and human brains. In doing so, especially from dissecting the brains of individuals who had suffered epilepsy (and also by deliberately causing lesions in the brains of living animals) much began to be discovered about how the human brain is structured, and which areas are involved in different behaviours.

As technology and academic integrity in science progressed, so did this fascinating field. One of the areas of cognitive neuroscience involves researching the areas of the brain responsible for communication. (This is one of Dr. Grossi's areas of research).

Our ability as human beings to use language to convey concrete and abstract concepts to one another is what sets us apart from every other animal on this planet. The human brain contains unique structures that are specialized for this complicated task.


In 1861, a physician named Paul Broca recorded the case of a man who had suffered a stroke and could no longer produce meaningful speech. It was discovered that the man had suffered severe damage to a section of his left temporal lobe, which is now known as "Broca's Area" --the area involved in producing speech. My father had a stroke, and as a result suffered severe Broca's Aphasia. He was unable to speak, although he retained much of his ability to comprehend written and spoken language. After diagnosis by a neurologist who conducts MRI brain imaging to locate the areas of damage, Broca's Aphasia is treated by Speech and Language Pathologists, who work with stroke survivors to help their damaged brains "re-learn" to speak, and also work to help these individuals master alternative methods of communication such as sign language, which is processed in a different part of the cortex.

Similarly, a physician named Wernicke encountered a stroke survivor who could produce language, yet it was entirely meaningless strings of words. The patient had lost receptive language skills. Damage to different area of the brain, now known as Wernicke's Area (located farther back in the temporal lobe) resulted in very different profound language impairment. Wernicke's Aphasia patients present a challenge to Speech and Language Pathologists because they are unable to comprehend instructions.

In 1870, German physicians ran an electrical current through the cortex of dogs causing them to produce characteristic movements based on where the current was applied. Since different areas produced different movements, the physicians concluded that behavior was rooted at the cellular level. Further to this, German neuroanatomist Korbinian Brodmann stained the brain tissues, finding that there were different types of cells in the brain, and that different areas of tissue controlled different functions. He concluded in 1909 that there were 52 distinct areas, now named "Brodmann Areas." The illustrations below show the differentiated functions of these areas.



Clearly then, cognitive neuroscience is one of the most exciting fields of neuroscience research. Apart from encompassing linguistics, it also addresses areas such as learning, memory and consciousness. As we embark upon our journey into the 21st Century, advances in Cognitive Neuroscience will help us on our quest to understand the very elements that make us human.

--Jenn Gilligan