Ritalin and the Human Brain

ATTENTION-DEFICIT/HYPERACTIVITY DISORDER SYMPTOMS IN SEARCH OF A CAUSE 

The symptoms of inattention, distractibility, and/or hyperactivity that define attention-deficit/hyperactivity disorder (ADHD) improve when treated with the stimulant drug Ritalin. For long-term success, however, the behaviors associated with these symptoms can also addressed with different techniques, some of which have been described in Chapter 2. 

These two different types of treatments point to two different causes for ADHD. The improvement observed when taking a chemical substance seems to indicate that ADHD has a biological cause. However, improvement by behavioral modification techniques suggests that ADHD may have an environmental cause. 

The prevalent theory among both health professionals and the general public today is that the symptoms of ADHD have a biological cause. The most generally cited causes are birth defects, an infant trauma, and the brain s inability to produce enough of specific neurotransmitters, or brain chemical messengers. 

The widespread use of expressions such as He has a chemical imbalance or Her brain is hard-wired this way when talking about children considered to have ADHD reinforces this belief. Although 

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One to 10% of the children who take Ritalin develop involuntary movements, or tics, such as blinking, playing with their fingers, or shoulder shrugging. These symptoms are usually associated with dyskinesias (abnormal muscle movements that stem from disrupted brain function), and also with Tourette s syndrome (a condition in which the tics are accompanied by uncontrollable vocalization of one or more words or sounds, which are often offensive). Although there was some preliminary evidence that Ritalin caused liver cancer in rats, further research did not substantiate this finding in humans. 

By increasing the activity of the neurotransmitter serotonin, Ritalin affects both higher human activities and basic physiological functions. In fact, increasing serotonin levels affects every brain function described in Table 3.1 on page 47. Some researchers believe that Ritalin produces more extreme mental... 

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