(taken from Wikipedia page on Hyperfocus - Jul 2009)
Hyperfocus is an intense form of mental concentration or visualization that focuses consciousness on a narrow subject, separate from objective reality and onto subjective mental planes, daydreams, concepts, fiction, the imagination, and other objects of the mind.
A positive aspect of hyperfocus might be the ability to use detachment from ordinary mentality to create new approaches to familiar situations. It may also improve learning speed and comprehension.
On the other hand, it sometimes presents a challenge to common teaching and parenting techniques. Schools and parents generally expect obedience from children and reward them for it, but hyperfocused children do not always cooperate under these circumstances. This can be overcome with investments of time and effort by the teacher or parent, but it is not always possible to spend a lot of time focusing on one child in a typical classroom situation.
Some people say that hyperfocus is an important element of meditation. In common parlance, hyperfocus is sometimes referred to as "zoning out."
Hyperfocus is not recognised by the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) and no article using the term appears in PubMed. Psychiatry describes only the distraction aspect of hyperfocus, referring to ADHD as 'inattentiveness and impulsiveness'.
However, not all aspects of hyperfocus are negative, and while not adressing it specifically, professional psychiatry does not completely discount the existence of hyperfocus.
Many adults with ADHD attribute accomplishments in their lives to this mental ability. Besides hyperfocus, various special abilities have been suggested to occur in ADHD, including vigilance, response-readiness, enthusiasm, and flexibility. But current ADHD research does not recognize these characteristics. Greater creativity has also been suggested, but formal measures of this are no higher in children with ADHD than in control groups.
Nevertheless, psychiatric research suggests that there are several reasons for the persistence of the notion that people with ADHD have the ability to hyperfocus, such as the well-recognised comorbidity of ADHD with autism spectrum disorders, of which excessive focus is a part. Special abilities do occur in some ADHD people, so it is easy to generalize from this minority to the whole ADHD group. ADHD is sometimes regarded as a disorder that is remarkably common (affecting 4-8% of school age children), but primarily genetically determined.
As ADHD in adults is a relatively new area of learning in comparison with the condition in children, many clinicians feel that hyperfocus is an aspect of adult ADHD which is not well understood and merits more thorough research.