The Anxiety Disorders Association of America reports that as of 2011 over 40 million adults aged 18 and older experience anxiety, which makes anxiety disorders among the most prevalent mental illnesses in America. The symptoms of anxiety vary, but may include restlessness, upset stomach, fatigue, irritability, increased heart rate and muscle tension. While the exact cause of anxiety is under debate in the medical community, the University of Maryland Medical Center suggests anxiety may be caused by irregular neurotransmitter balance, which may include dopamine.
Role of Dopamine
Dopamine is defined as a chemical neurotransmitter located within the substantia nigra portion of the brain. This chemical is responsible for determining how the brain reacts to an emotional response, pleasure, pain and bodily control. The University of Texas Addiction Science Research and Education Center reports dopamine levels within the brain play a vital role in a person's physical and mental well-being. Dopamine deficiencies are linked to anger, depression, mood swings, hyperactivity, high blood pressure and difficulty achieving orgasm, according to Caring Medical and Rehabilitation Services.
Dopamine and Anxiety
The Dana Foundation reports dopamine levels within the amygdala portion of the brain may directly affect anxiety within a person. This portion of the brain is responsible for processing emotions based on environmental stimuli. The report "Dopamine Linked to 'Anxious' Amygdalas" suggests high dopamine levels found within this almond-shaped portion of the brain result in reduced "trait anxiety" while low dopamine levels increased a person's disposition to anxiety. The report continues to suggest as the brain ages, dopamine levels within the amygdala dissipate, which raises the possibility that aging alone may increase the anxiety levels within the brain.
Drugs and Dopamine Levels
Dopamine levels within the brain are directly affected by certain medications. While medications designed to treat Parkinson's disease stimulate dopamine receptors, medications to treat schizophrenia typically slow down the production of dopamine. Illegal drugs also affect dopamine receptors and distribution. The University of Texas Addiction Science Research and Education Center states that drugs such as cocaine or methylphenidate may increase dopamine production, but in turn inhibit dopamine reuptake, thus over time, dopamine receptor desensitization and sensitization may occur. Due to the irregularities within the brain caused by prescription or illegal drugs, dopamine levels may be disrupted and increase the level of anxiety within the brain.
Increasing Dopamine
Dopamine levels within the brain may be increased through medications and dietary sources. Prescription medications such as methylphenidate and bupropion have shown to increase dopamine production. For example, Brookhaven National Laboratory states in the report "New Brookhaven Lab Study Shows How Ritalin Works," subjects showcased a significant increase in dopamine levels within 60 minutes after ingesting the drug. Foods such as pumpkin seeds, almonds, avocados, lima beans and antioxidant-rich fruits and vegetables may help increase dopamine production, according to the journal "Integrative Psychiatry."
References
- The Dana Foundation; Dopamine Linked to Anxious Amygdalas; Jim Schnabel; December 2008
- University of Texas Addiction Science Research and Education Center: Dopamine -- A Sample Neurotransmitter
- University of Maryland Medication Center; Anxiety; Steven D Ehrlich, NMD; December 2009
- Anxiety Disorders Association of America: Facts and Statistics
- Caring Medical & Rehabilitation Services: Dopamine
- Brookhaven National Laboratory; New Brookhaven Lab Study Shows How Ritalin Works; January 2001
