Sluggish cognitive tempo

Sluggish cognitive tempo (SCT) is a cluster of symptoms that may comprise a novel attention disorder which is distinct from ADHD. It is characterized by dreaminess, mental fogginess, hypoactivity, sluggishness and a slow working speed.

Although SCT has been a subject of controversy for decades, definitions for this proposed disorder are still being developed. Some psychologists and psychiatrists think it should be its own psychiatric disorder. Others dismiss it altogether or believe it is a separate symptom domain within ADHD (like Hyperactivity, Impusivity or Inattention). A few researchers think it may even be useful as a transdiagnostic concept that is shared among different mental disorders, similar to emotional dysregulation.

Originally, it was thought that only a subset of the inattentive type of ADHD manifested SCT and that it was apparently incompatible with hyperactivity. But new research showed that SCT is also frequently seen in the combined type, in some with the hyperactive-impulsive type and in individuals who would not receive an ADHD diagnosis. Efforts are underway to encourage the use of the term Concentration Deficit Disorder (CDD) for SCT.

ADHD is the only disorder of attention currently defined by the DSM-5 or ICD-10. Formal diagnosis is made by a qualified professional, and includes demonstrating six or more symptoms of inattention, hyperactivity and impulsivity, or both. This results in three types of ADHD:

The symptoms must also be inappropriate and must interfere with social, school, or work functioning, in addition to meeting multiple other diagnostic requirements. The symptoms used in the diagnosis are shown below.

SCT is proposed to be a similar disorder to the predominantly inattentive presentation (ADHD-I), but, as discussed later, importantly distinct from it. One problem is that some individuals who actually have SCT are now mistakenly diagnosed with the inattentive presentation. The list of symptoms that follows is from leading researchers of SCT, however, no universally accepted set of symptoms has been developed since this symptom cluster has not yet been recognized as an independent disorder.

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