Richard Saul is a behavioral neurologist who has offered second opinions to hard-to-treat patients, many of them children, for more than 30 years. Not once has he confirmed an initial diagnosis of ADHD. Using detailed case histories, Saul argues that conditions that present as ADHD are most likely the result of vision, sleep, or mood disorders, to name the most common. Indeed, a child who roams the class while others are copying from the board, or is too listless to respond to a query, might in fact be myopic, sleep deprived, or consumed with anxiety.
But as Saul rules out ADHD chapter by chapter, instead implicating more than 15 conditions from seizure disorders to fetal alcohol syndrome, he puts forth a new argument. Apparently more prevalent than schizophrenia, but less common than Asperger’s, is a condition not found in the DSM-V but so germane to Saul’s clinical experience that he’s created a term for it: neurochemical distractibility/impulsivity (NDI). NDI is caused by irregular neurotransmitter activity, specifically low levels of whole-blood serotonin or high levels of epinephrine/norepinephrine. The symptoms are classic deficits in attention and executive functioning, as the name suggests, and NDI is treated with stimulants, just like ADHD. Why the semantic fuss? Saul claims that NDI is a causal description whereas ADHD is perilously broad and exclusively symptom-based. One wonders how NDI relates to the literature about neurotransmitters and ADHD, but Saul does not engage on the level of neuroscience beyond staking a claim to the term NDI.