Search Results And Quality Rating
Searching identified 361 publications across the 6 different areas of research, among which seventeen studies fulfilled inclusion criteria . Included studies, their characteristics and results are shown in Table . As no systematic review or meta-analysis had been performed within the last 10 years on serotonin depletion, we also identified the 10 latest studies for illustration of more recent research findings .
Quality ratings are summarised in Table and reported in detail in Tables . The majority of systematic reviews and meta-analyses satisfied less than 50% of criteria. Only 31% adequately assessed risk of bias in individual studies , and only 50% adequately accounted for risk of bias when interpreting the results of the review. One collaborative meta-analysis of genetic studies was considered to be of high quality due to the inclusion of several measures to ensure consistency and reliability . The large genetic analysis of the effect of SERT polymorphisms on depression, satisfied 88% of the STREGA quality criteria .
What Is A Chemical Imbalance In The Brain
Neurotransmitters are natural chemicals that help ease the communication between your nerve cells. Examples include norepinephrine and serotonin.
Some people claim that mental health conditions, such as depression and anxiety, result from a chemical imbalance in the brain. The hypothesis is sometimes called the chemical imbalance hypothesis or chemical imbalance theory.
However, its important to know that the chemical imbalance theory requires revision. Communication between neurons in the brain in the processes underlying depression.
However, much research states that an imbalance of neurotransmitters does not cause depression.
Structures within the brain, including the frontal lobe and hippocampus, regulate your mood and emotions.
Studies have observed
Is Depression Caused By A Chemical Imbalance Debunked
The human brain is a highly complex organ that contains about 86 billion nerve cells. These can make a possible 1,000 trillion unique connections, and the cells themselves can send pulses of electrical information at speeds of up to 400 kilometres per hour4. Its truly an amazing organ that has rocketed us to the very top of the food chain.
But scientists still have a lot to learn about it, particularly its role in depression and other mental health issues.
Is depression caused by a chemical balance? Noits not as simple as that. Depression is thought to be caused by a combination of possible factors, one of which may be a chemical imbalance. Neurotransmitters like serotonin, dopamine, and norepinephrine can play a role in depression, but it isnt as simple as a certain chemical being too high or low. Scientists dont even understand what a balanced amount of chemicals looks like.
If a chemical imbalance was solely to blame for depression, SSRIs should be 100% effective. But theyre not. They absolutely can work wonders for some people5, but again, scientists arent really sure why they dont work for everyone. In addition to this, medications that are not SSRIs have also shown to help with depression symptoms, again suggesting that fixing a chemical imbalance does not cure depression by itself.
What causes depression?
A variety of factors are thought to contribute to depression, including:
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Is Depression Even A Single Disease
While Moncrieffs review is focused on disproving the idea of a particular cause of depression, perhaps the focus of debate should instead be on the idea that depression is a single disease. Today, it is largely accepted that depression is a heterogeneous disorder with potentially multiple underlying causes, says Prof. Gitte Moos Knudsen of the Copenhagen University Hospital, Denmark. As we have reframed cancer as not one but many diseases, perhaps mental health disorders like depression should be rethought of as resulting from many different environmental and biological factors. Abandoning the sole serotoninergic focus of the chemical imbalance model is a necessary part of that shift in thinking, but more work will have to be done to reframe the publics perception of the complex biology of depression.
Depression The Chemical Imbalance Myth And What Causes Depression
Depression affects a relatively large portion of Americans. It is normal to feel depressed on occasion, but severe negative moods and lack of interest in what was once considered a pleasurable activity, for a prolonged length of time , may reflect major depressive disorder. Approximately 16% of Americans will experience major depressive order at some point in their lives . Major depressive disorder varies in severity and can persist anywhere from months to years. For some people it becomes debilitating and can contribute to other health problems. Depression is the leading risk factor for suicide, and is among the top three causes of death for people between ages 15 and 35 . Depression may not only alter the life of those who experience it, but also the lives of those close to the sufferer. If you have ever been close with someone suffering major depression you have probably witnessed the life disruption it entails.
Most antidepressants promote the growth of new cells and new brain connections it may be that the primary mechanisms underpinning successful drug treatment involve these factors. Jarrett suggests that the most important action of antidepressants might be to increase the growth of new brain cells.
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Treatment For Chemical Imbalances
There is no one-size-fits-all answer for the treatment of chemical imbalances. However, many people find relief with medications and/or therapy.Therapy may involve different treatments such as cognitive behavioral therapy , dialectical behavior therapy , or family-focused therapy. Medications used to treat chemical imbalances include antidepressants, antipsychotics, and mood stabilizers.
Its important to note that not everyone who has a mental health condition needs medication. Some people only require therapy, while others may need a combination of medication and therapy. And still others may only need medication.
Recovery and treatment options will often need professional and emotional support. If you face a dual diagnosis in which addiction comes with other illnesses, you may face even bigger obstacles. However, you can rest assured that rehab centers have plans and programs to help you. Addiction treatment therapies that can help include:
- Cognitive-behavioral therapy
How Did The Chemical Imbalance Theory Start
The first two antidepressant medications, both discovered in the 1950s, were observed to have positive effects on mood as side-effects of their hoped-for functions. Iproniazid was developed as a treatment for tubercolosis, and imipramine as an antihistamine.
We know now that ipronizaid is a monoamine oxidase inhibitor it stops the enzyme that breaks down serotonin and similar brain chemicals. But we didnt know this when its antidepressant effects were first observed in 1952.
Imipramine is a tricyclic antidepressant and, among other effects, it blocks the reuptake of serotonin after it has been secreted, also allowing more to stay in the brain.
A simple hypothesis then presented itself: if both classes of antidepressants were shown to increase brain levels of serotonin, then depression must be caused by low levels of serotonin.
Researchers set out to demonstrate this in patients with depression, showing that serotonin and its metabolites and precursors were lower in the blood, in the cerebrospinal fluid, and so on.
But these studies suffered from what we now know plagued many studies of their era, leading to the so-called replication crisis. Studies used small sample sizes, selectively reported their results and, if they failed to demonstrate the hypothesis, were often not reported at all. In short, the findings were unreliable, and since then larger studies and meta-analyses made it clear the hypothesis wasnt supported.
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So Are Antidepressants Effective
The new paper by Moncrieff and colleagues, while not saying anything new, does us all a favour by reiterating the message that has been clear for some time: there is no evidence to support the chemical imbalance theory. Their message has been amplified by the extensive media attention the article has received.
But much of the commentary has extrapolated from the studys finding to suggest it undermines the effectiveness of antidepressants including by the authors themselves.
This shows a misunderstanding of how medical science works. Medicine is pragmatic. It has often established that a treatment works well before it has understood how it works.
Many commonly used medicines were used for decades before we understood their mechanisms of action: from aspirin to morphine to penicillin. Knowing they worked provided the impetus for establishing how they worked and this knowledge generated new treatments.
The evidence for SSRIs being effective for depression is convincing to most reasonable assessors. They are not effective for as many people with depression as we might hope, as I have written before, but they are, overall, more effective than placebo treatments.
Critics suggest the magnitude of the difference between the medications and placebo isnt great enough to warrant their use. That is a matter of opinion. And many people report significant benefits, even as some people report none, or even that they have caused harm.
What Is The Biochemical Basis Of Depression
Steven Gans, MD is board-certified in psychiatry and is an active supervisor, teacher, and mentor at Massachusetts General Hospital.
There are several theories about what causes depression. The condition most likely results from a complex interplay of individual factors, but one of the most widely accepted explanations cites abnormal brain chemistry.
Sometimes, people with depression relate the condition back to a specific factor, such as a traumatic event in their life. However, it’s not uncommon for people who are depressed to be confused about the cause. They may even feel as though they don’t have “a reason” to be depressed.
In these cases, learning about the theories of what causes depression can be helpful. Here’s an overview of what is known about how chemical imbalances in the brain may influence depression.
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Chemical Imbalances And Mental Health
The imbalance of chemicals in the brain is only one of the many factors that may contribute to mental health challenges. Other important factors include family history and genetics, as well as life experiences . Drug and alcohol use, as well as certain medications, also contribute.
Lastly, psychological factors such as situations leading to loneliness and isolation can cause mental health problems. There does seem to be a link between chemical imbalances and mental health. However, there is still no concrete explanation of how brain chemicals become imbalanced in the first place.
Some of the mental health conditions linked to chemical imbalance include:
Possible Explanations For Antidepressants Small Effect
First, although brain biology is involved in everything we think and feel, there are no established specific biological causes of depression. Other proposed ways in which antidepressants might target underlying mechanisms are hypotheses, often drawn from animal studies or cells in a dish and none have been consistently demonstrated in humans.
Second, there is another explanation for what antidepressants do. Antidepressants are drugs that change brain chemistry, and like other drugs that do this, they produce changes in our mental states and experiences. These changes can temporarily override our current feelings.
For example, alcohol has sedative and relaxing effects that can reduce anxiety and briefly drown your sorrows, but this is not because alcohol works on the underlying mechanisms of anxiety or depression. Alcohols effects are experienced by everyone and not just people with one of these diagnoses.
Antidepressants do not commonly make people merry like alcohol can. They cause a variety of more or less subtle mental alterations, depending on the chemistry of the drug. One common, dose-dependent alteration, is numbingof emotions.
This effect could also explain why antidepressants perform a little better than placebo in randomised trials. In the short term, the numbing may make people feel less depressed, but in the long term, the benefits are less clear.
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Chemical Imbalances And Depression
You often hear the words chemical imbalances associated with addiction and mental health. Knowing what this term means is a great help in understanding many psychiatric conditions. Chemical imbalances happen when the brain has either too many or too few neurotransmitters. These neurotransmitters are natural chemicals that help the nerve cells to communicate with each other. Examples of these chemicals include dopamine, serotonin, and norepinephrine.
Mental health issues, such as anxiety, depression, and addiction, are affected by an imbalance of brain chemicals. However, there is much more to mental illnesses than only chemical imbalances. However, drugs and alcohol use can be important factors as they affect neurotransmitters, which may lead to addiction and the need for an addiction treatment center. Through treatments, such as , you can begin healing. To learn more about our services, please contact Georgia Addiction Treatment Center today at .
Immune System & Inflammation
Inflammation is the bodys response to a perceived threat, such as a cut or infection. When it becomes widespread or chronic, it can wreak havoc in the body and brain. In fact, studies show that chronic, low-grade inflammation is associated with increased risk for depression and other mental illnesses. Possible sources of inflammation include poor diet, stress, changes in the gut microbiome, and certain medical illnesses.
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Debunking The Two Chemical Imbalance Myths Again
Moving toward a bio-psycho-sociocultural model of major depression.
For reader feedback, see Chemical Imbalance? Readers Respond.
Dr Pies is Professor in the psychiatry departments of SUNY Upstate Medical University, Syracuse, NY and Tufts University School of Medicine, Boston. He is Editor in Chief Emeritus of Psychiatric Times .
A little learning is a dangerous thing. – Alexander Pope1
Like the legendary Count Dracula, who could be killed only by driving a stake through his heart, some myths seem almost immortal. For more than 8 years now, I have tried to drive a stake through the heart of two myths regarding the so-called chemical imbalance theory-but with only limited success, as a recent piece in the New Yorker brought home to me.2-5
Ironically, anti-psychiatry groups are quite right in heaping scorn on the chemical imbalance theory of mental illness, but not for the reasons they usually give. . The fact is, there could never have been a scientifically based, chemical imbalance theory of mental illness, because a genuine theory requires an integrated network of well-supported, interlinked hypotheses. And yes, the frequently ignored distinction between a theory and a hypothesis is crucial. It is the key to understanding why claims by antipsychiatry bloggers regarding the chemical imbalance theory nearly always crash and burn.
The theory that never was
Psychiatrists questioned the chemical imbalance theory
The bio-psycho-sociocultural model
Causes Of Depression: Beyond Chemical Imbalances And Genetics
If youve ever struggled with depression, you may have wondered, Why am I sad for no reason? or Why am I sad all the time? Maybe you think that depression is a chemical imbalance in the brain, or that youre destined to live with this condition because youve seen a parent, sibling, or other family member suffer from it.
In reality, depression is a much more complex condition that stems from many different causes.
In this article, well share a new framework for understanding depression as a whole-body condition, as well as some of the recent research around the biological causes of depression. We discuss questions including:
As a psychiatrist using the integrative medicine approach for over 15 years, I have seen many patients who did not improve with talk therapy and antidepressants finally get the answers and treatment that they desperately need through this new framework of depression.
Recommended Reading: What Are Strategies For Coping With Depression
What Is A Chemical Imbalance
A chemical imbalance occurs when the substances that help the body function the way it should become out of balance. Either too much or too little of these substances can cause a chemical imbalance that affects the bodys ability to function normally.
These chemical imbalances are often linked to health conditions. For example, a hormonal imbalance occurs with polycystic ovary syndrome , which in turn puts a person at risk for other conditions such as type 2 diabetes and infertility.
While too much or too little of these substances anywhere in the body is considered a chemical imbalance, the term chemical imbalance is usually associated with chemical imbalances in the brain and their potential effect on mental heath and related conditions.
Brain Chemicals And Depression
Researchers have suggested that for some people, having too little of certain substances in the brain could contribute to depression. Restoring the balance of brain chemicals could help alleviate symptomswhich is where the different classes of antidepressant medications may come in.
Even with the help of medications that balance specific neurotransmitters in the brain, depression is a highly complex condition to treat. What proves to be an effective treatment for one person with depression may not work for someone else. Even something that has worked well for someone in the past may become less effective over time, or even stop working, for reasons researchers are still trying to understand.
Researchers continue to try to understand the mechanisms of depression, including brain chemicals, in hopes of finding explanations for these complexities and developing more effective treatments. Depression is a multi-faceted condition, but having an awareness of brain chemistry can be useful for medical and mental health professionals, researchers, and many people who have depression.
Depression Discussion Guide
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University College London Research Says Depression Is Not A Serotonin Imbalance And Drugs That Target It May Not Be The Answer
In this July 10, 2018, file photo, bottles of medications ride on a belt at a mail-in pharmacy warehouse in Florence, N.J. While many people take antidepressants, a new study raises doubt that chemical imbalance in the brain is responsible for depression.
Millions of Americans take antidepressants, but a new study suggests the theory underpinning their use may be entirely wrong. Research from the University College London raises doubt that chemical imbalance in the brain is responsible for depression.
A major review of previous studies on serotonins role in depression, just published in the journal Molecular Psychiatry, concluded that serotonin level the target of antidepressants is not responsible for depression.
The researchers found no support for the hypothesis that depression is caused by lowered serotonin activity or concentrations.
They found stronger evidence that stressful life events can lead to depression.
The question is, do antidepressants help, and if so, how? If not, could they be doing harm?
Experts are divided and the study has drawn some pushback.
Most antidepressants are selective serotonin reuptake inhibitors, which were originally said to work by correcting abnormally low serotonin levels. There is no other accepted pharmacological mechanism by which antidepressants affect the symptoms of depression, the researchers said in a news release.