<ul><li>By Natalee Embry </li></ul>ADHD and the Brain
In this presentation I hope to attempt to teach that ADHD is a brain based disorder. I will cover the areas of the brain that are affected and the triad of neurotransmitters that are involved in this disorder. Most people are aware of what ADHD looks like on the outside but I believe to truly understand ADHD we should know what is happening on the inside.
ADHD is not caused by: Will Power Inadequate Parenting Lack of Motivation Lack of Intelligence Laziness
Meet a few accomplished people who have ADHD : Ozzy Osbourne
ADHD is now believed to be a Neurological Disorders ( Brain Based) which can be genetic yet the specific cause is still unclear. What we do know is there is a lack of: * Regulation of Attention * Regulation of Motor Activity * Regulation of Impulsivity. Forssberg et al. (2006)
The thought is that there are several areas of the brain that may be affected by ADHD. Some of these areas are: Frontal Lobes/Prefrontal Cortex Limbic System Basal Ganglia Forssberg et al. (2006)
The Frontal Lobe/Prefrontal Cortex helps us to: Focus Concentration Pay Attention to our tasks Make good decisions Plan Ahead Learn and to remember what we have learned. To have proper behavior in situations where it is required. Armstrong (2010)
The prefrontal cortex is one of the last areas of the brain to fully mature. In patients with ADHD it is hypothesized that they mature at a slower rate than their peers without ADHD, sometimes between two and three years slower. However it must be said that children with ADHD do undergo normal patterns of brain development they just lag behind their peers . Armstrong (2010)
The Cerebellum is responsible for producing coordinated muscle movements. It also works to sequence thoughts of motion. Sweeney (2010), Armstrong (2010) Basal Ganglia also helps with movement and motor control. Dopamine, either too much or too little affects how the Basal Ganglia communicates to the rest of the brain. Sweeney (2009), Armstrong (2010)
These areas of the brain are now being analyzed more closely due to improvements in brain scans. We can now see more closely what is happening inside an active brain of someone with ADHD. The scans most often in use for research of ADHD are MRI & fMRI (Magnetic Resonance Imaging, functional Magnetic Resonance Imaging) PET (Positron-Emission Tomography)
MRI allows for a three dimensional look at the brain. With this scan the brain can also be seen in individual layers for a more localized view of a particular area. It shows a precise picture of the physical shape of the brain. Sweeney (2009)
fMRI A newer scan option that uses blood flow to show images of the working brain. Much like the PET yet no radioactive chemicals need to be used. It relies on magnets that surrounds the persons head. Changes in the direction of the magnetic field induce hydrogen atoms in the brain to emit radio signals. These signals increase when the level of blood oxygen goes up, indicating which parts of the brain are most active. Sweeney (2009)
PET scans use radioactive isotopes that are injected into the blood stream and then traced by a computer as it travels through the brain. This type of test allows us to watch a living brain in action as it reveals blood flow, oxygen and glucose metabolize in the brain. Sweeney (2009)
There are chemical differences in the brains of people with ADHD. These chemicals are: Dopamine Norepinephrine New Research is also suggesting: Glutamate Serene et al. (2007)
Dopamine is a neurotransmitter that transmits signals in between nerve cells. Dopamine influences the functions of the brain that include regulating attention, cognition, movement, pleasure the area of the frontal lobes/prefrontal cortex need dopamine to function and mature properly . People with ADHD have disturbances in the dopamine system innervating the basal ganglia and the frontal lobes. The lack of dopamine makes it difficult for someone with ADHD to pay attention to non stimulating activities. Its not that people with ADHD are over stimulated rather they are under stimulated. Forssberg et al.(2006) Armstrong (2010)
Norepinephrine is a neurotransmitter that is responsible for moving nerve impulses between neurons. acting as a neurotransmitter Norepinephrine’s role is for arousal and attentiveness. A lack of norepinephrine causes issue’s with attention and emotional responses. Sweeney (2009) Glutamate is also a neurotransmitter and its role is important to learning and memory. Small quantities of glutamate “excite” cells to increase activity. Too much glutamate however can have damaging effects by killing neurons. Sweeny (2009)
Research is now finding that people with ADHD have higher levels of glutamate in the anterior cingulated cortex, this part of the brain helps regulate rational thought such as anticipating rewards, making decisions, having/feeling empathy as well as regulate emotion. This area of ADHD research is relatively new and more research is needed. Glutamate is crucial to the brain. Serene et al. (2007)
So what does this all mean? It means that ADHD is a brain based disorder. We are still unsure what the specific initial cause is. The relationship between dopamine, nor epinephrine and glutamate are the triad of chemicals that are specifically affected in the brains of ADHD people. We are certain of the areas of the brain that is being affected in people with ADHD and we know what the roles of those parts of the brain are.
Research is being expanded due to newer high tech imaging machines and computer programs that are allowing scientist to see the active human brain in ways they have never seen before opening doors to better research and possibly even a cure, but better treatments for certain. Also, we know that ADHD does not mean that a person cannot be successful and achieve great things. Never forget the child inside you
Armstrong, T. (2010) . Neurodiversity: Discovering the extraordinary gifts of Autism, ADHD, Dyslexia, and other brain differences . Philadelphia: Da Capo Press This books attempts to point out the many advantages to different brain disorders and their role in evolution. A positive approach at discovering the many reasons behind the disorders and how people with them can flourish outside of their brain disorder labels. It steps aside from stereotypes of psychiatric medicine and focuses on getting the most out of a “different mind”. Forssberg, H., Fernell, E., Waters, S., Waters, N., & Tedroff, J. (2006). Altered pattern of brain dopamine synthesis in male adolescents with attention deficit hyperactivity disorder. Behavioral & Brain Functions , 240-10. doi:10.1186/1744-9081-2-40 Retrieved from EBSCO host A research article that was aimed at trying to locate inside the brain what areas were lacking in dopamine function. Using PET scans they compared results between ADHD and control groups. Their findings were conclusive that there were dopamine receptor differences, yet they were only able to focus on small areas for their results. ADHD needs to be broken down into further subtypes and those areas be studied specifically. There is yet no one theory of ADHD that is conclusive. Serene, J., Ashtari, M., Szeszko, P. R., & Kumra, S. (2007). Neuroimaging Studies of Children With Serious Emotional Disturbances: A Selective Review. Canadian Journal of Psychiatry , 52(3), 135-145. Retrieved from EBSCO host . A reasearch article using data from published reports that attempts to briefly describe findings. MRI imagining that shows the potential for children with psychiatric disorders to have underlying neurodevelopmental issues. It supports the need for more brain imaging testing to further the potential diagnosis and treatment for child psychiatric disorders. Sweeney, M. (2009). Brain the complete mind . Washington, D.C. : National Geographic Society College level text book that teaches about the human brain. It uses current issues and discoveries about the development of the human brain. This text covers the brain from in utero through the aging process with everything that happens in between.