Obsessive compulsive disorder, or OCD, is an anxiety disorder which, like many anxiety disorders, is marked by low levels of serotonin. Serotonin, a type of neurotransmitter, has a variety of functions that make a deficiency a serious and anxiety producing issue.
However, recent studies have linked obsessive-compulsive disorder to imbalances in brain chemistry. These changes usually involve serotonin, which controls moods and feelings. Then there is always the genetic link.
Glutamatergic neurotransmission is the principal neurotransmitter implicated in the CSTC model of OCD. Hyperactivity in the CSTC loop implies a high level of glutamate in the cortical-striatal pathways as well as a dysregulation of GABAergic transmission, and could represent the pathophysiology of OCD.
Is OCD Caused by a Chemical Imbalance? Changes in the neurochemical serotonin, as well as in the neurochemicals dopamine and glutamate, are likely present in OCD. Indeed, medications like the antidepressants known as selective serotonin reuptake inhibitors (SSRIs) improve symptoms for many people.
Reduced dopamine D1 receptors and dopamine D2 receptors in the striatum have been reported in people with OCD, along with both increased and decreased reports of dopamine transporter (DAT) binding.
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Obsessive compulsive disorder, or OCD, is an anxiety disorder which, like many anxiety disorders, is marked by low levels of serotonin. Serotonin, a type of neurotransmitter, has a variety of functions that make a deficiency a serious and anxiety producing issue.
While brain structure may play a role in developing OCD, chemical imbalances in the brain have not been found to be a contributing cause of OCD.
Preclinical, neuroimaging and neurochemical studies have provided evidence demonstrating that the dopaminergic system is involved in inducing or aggravating the symptoms that are indicative of OCD.
Research has also suggested that both estradiol and progesterone increase dopaminergic signaling and worsening OCD symptoms.
Three brain areas – the orbitofrontal cortex (OFC), the anterior cingulate cortex (ACC), and the head of the caudate nucleus – have been consistently implicated in a large number of resting, symptom provocation, and pre/post-treatment studies of adults with OCD.
Causes of OCD
Compulsions are learned behaviours, which become repetitive and habitual when they are associated with relief from anxiety. OCD is due to genetic and hereditary factors. Chemical, structural and functional abnormalities in the brain are the cause.
Magnetic resonance imaging (MRI) scans conducted to compare the volumes of different brain regions in people with and without OCD have found smaller volumes of the orbitofrontal cortex and the anterior cingulate cortex in individuals with OCD.
"We know that OCD is a brain-based disorder, and we are gaining a better understanding of the potential brain mechanisms that underlie symptoms, and that cause patients to struggle to control their compulsive behaviors," says Norman.
Etiology: Biological Models. Many investigators have contributed to the hypothesis that OCD involves dysfunction in a neuronal loop running from the orbital frontal cortex to the cingulate gyrus, striatum (cuadate nucleus and putamen), globus pallidus, thalamus and back to the frontal cortex.
Serotonin Reuptake Inhibitors (SSRIs) work well to help control OCD symptoms. Serotonin-Norepinephrine Reuptake Inhibitors (SNRIs) are another type of antidepressant that can be helpful to people suffering from OCD symptoms. The following antidepressants are FDA approved to treat OCD: Anafranil (clomipramine)
OCD fundamentally changes the brain, showing a significant reduction in grey matter density in some regions. In severe cases, this can permanently change how the brain works for patients with OCD. However, most people can lead normal and happy lives with therapy and medication.
However, one thing that is clear is that comorbidities, stress, anxiety, and major life changes or circumstances can all play a significant role in how much worse OCD might become. As symptoms increase or intensify, people with OCD may also experience the following: Failure at work and/or school.
Primarily obsessional OCD has been called "one of the most distressing and challenging forms of OCD." People with this form of OCD have "distressing and unwanted thoughts pop into [their] head frequently," and the thoughts "typically center on a fear that you may do something totally uncharacteristic of yourself, ...
Research suggests that OCD involves problems in communication between the front part of the brain and deeper structures of the brain. These brain structures use a neurotransmitter (basically, a chemical messenger) called serotonin.
Unfortunately, OCD doesn't just go away. There is no “cure” for the condition. Thoughts are intrusive by nature, and it's not possible to eliminate them entirely. However, people with OCD can learn to acknowledge their obsessions and find relief without acting on their compulsions.
These infections may include: strep, influenza, mycoplasma pneumonia, Lyme disease, herpes virus, mononucleosis and Coxsackie virus. This autoimmune response targeting the basal ganglia can cause brain inflammation and the onset of neuropsychiatric symptoms, including OCD-like behaviors.
Fluoxetine (Prozac) for adults and children 7 years and older. Fluvoxamine for adults and children 8 years and older. Paroxetine (Paxil, Pexeva) for adults only. Sertraline (Zoloft) for adults and children 6 years and older.