Are you having difficulty concentrating? If you can maintain focus until the end of this blog post, you may learn how your catecholamines are involved in concentration—or lack thereof.
Attention and the Catecholamines, Norepinephrine and Dopamine
Norepinephrine and Dopamine are part of the catecholamine family of neurotransmitters which are derived from the amino acids phenylalanine and/or tyrosine.
The catecholamines are important in regulating functions of the prefrontal cortex of the brain (1).
Norepinephrine (or Noradrenaline) is involved in brain functions such as:
- Mood regulation
- Drive and ambition
- Learning and memory
Dopamine in the brain:
- Enhances memory
- Promotes focus
- Provides salience, or preferential attention to external stimuli that promise reward
Norepinephrine and Dopamine pathways in the Central Nervous System interact with each other, so they must both be in balance to synergistically perform normal prefrontal cortex functions. Too much or too little of either neurotransmitter can impair our ability to focus (1).
ADHD and The Inability to Focus
An extreme inability to focus can be seen in people with ADHD.
Attention Deficit/Hyperactivity Disorder (ADHD) is classified as a neurobehavioral disorder. It is found primarily in children and adolescents. Though it is a complex disorder, the primary symptoms are inattention, impulsiveness and hyperactivity (2).
According to the CDC, about 11% of children 4-17 years old in the United States (that’s 6.4 million!) have been diagnosed with ADHD (3). ADHD is considered to be a public health concern because of its close association with substance abuse and delinquency (4).
ADHD and Norepinephrine and Dopamine
Norepinephrine and Dopamine are both involved in the pathophysiology of ADHD. In fact, the primary drugs used to treat ADHD (MPH and D-AMPH) function as Dopamine and Norepinephrine reuptake inhibitors (2).
Studies of ADHD have shown the disorder to have a very large genetic component (4). If one of your parents had ADHD, you would be much more likely to also have it yourself.
Some of the genes involved in ADHD control the abundance and transmission of catecholamines.
Researchers have found the genes coding for the Norepinephrine transporter, D4 Dopamine receptor, and the Dopamine transporter to be associated with ADHD symptoms (4,5,6). Inattention and impulsivity were associated with polymorphisms in these genes in both ADHD and non-symptomatic people (4).
These findings demonstrate how Dopamine and Norepinephrine are involved in attention and concentration processes in healthy brains, and how understanding their dysfunction could explain some of the symptoms of this complex disorder.
Again, balance between these two catecholamines is essential for normal cognitive function! That is why testing levels of neurotransmitters is so important for supporting those with ADHD, ADD, or anyone who needs help staying focused.
- Bo Xing, Yan-Chun Li, Wen-Jun Gao. (2016). Norepinephrine versus dopamine and their interaction in modulating synaptic function in the prefrontal cortex. Brain Research, 1641, 217-233.
- Del Campo N, Chamberlain SR, Sahakian BJ, et. al. (2011). Biological Psychiatry. The Roles of Dopamine and Noradrenaline in the Pathophysiology and Treatment of Attention-Deficit/Hyperactivity Disorder. 69,145–157.
- The Centers for Disease Control and Prevention. (2016). Attention-Deficit/Hyperactivity Disorder. Retrieved from http://www.cdc.gov/ncbddd/adhd/data.html
- Gizer IR & Waldman ID. (2012). Double Dissociation Between Lab Measures of Inattention and Impulsivity and the Dopamine Transporter Gene (DAT1) and Dopamine D4 Receptor Gene (DRD4). Journal of Abnormal Psychology, 121(4), 1011-1023.
- Faraone Stephen V, Biederman J, Weiffenbach B, et. al. (1999). Dopamine D4 gene 7-repeat allele and attention deficit hyperactivity disorder. The American Journal of Psychiatry, 156(5), 768-770.
- Sengupta SM, Grizenko N, Thakur GA, et. al. (2012) Differential association between the norepinephrine transporter gene and ADHD: role of sex and subtype. Journal of Psychiatry and Neuroscience, 37(2),129-37.