Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterised by persistent symptoms of inattention, impulsivity, and hyperactivity. These symptoms must cause significant impairment in social, academic, or occupational functioning. It is prevalent worldwide, with prevalence estimates ranging from 1-5%. Yet how did scientists come to this definition of ADHD? This article will offer a brief glimpse of the history of ADHD, from its early beginnings in the mid-19th century up to today.
One of the earliest reports of ADHD in the literature comes from an anecdotal children’s story by Heinrich Hoffman. Hoffman’s 1884 story is believed to be describing a young boy known as ‘Fidgety Phil’ with ADHD-like symptoms causing a fuss at dinner time.
The 1902 lectures by Sir George Frederic Still are considered by many scientists and researchers to be the scientific starting point of the history of ADHD. Still talked about a defect of moral control in a group of children – who lacked “the control of an action in conformity with the idea of the good of all”. Still also remarked that this particular group of children had no “general impairment of intellect” i.e. they were children of average intelligence with no major deficits. His patients were also reported as having an abnormal incapacity for sustained attention by both parents and teachers. This relates to the current ADHD criteria for ADHD symptoms to be present in more than one setting (for example, at home and at school).
Franz Kramer and Hans Pollnow reported on a hyperkinetic disease in infancy, of which the most characteristic symptom was motor restlessness. Kramer and Pollnow noted that patients had remarkable motor activity which appeared to be very urgent. This can be related to today’s concept of hyperactivity. Patients were also reported to not be able to remain still for prolonged periods of time. This is similar to the American Psychiatric Association’s description of children with ADHD as being “driven by a motor” (2000). Kramer and Pollnow also make references to distractibility, and patients having difficulty completing tasks or concentrating.
In 1937, Charles Bradely reported a positive effect of stimulant medication in children with various behaviour disorders. He discovered that the stimulant Benzedrine was most likely to benefit children with short attention spans, dyscalculia, mood lability, hyperactivity, impulsiveness, and poor memory. As such, this was the first use of stimulant medication as a treatment for ADHD.
Scientists discovered a pattern of hyperactivity being related to reports of brain damage in children. Research in the 1930s and 1940s supported the idea of a causal connection between brain damage and abnormal behaviour. Thus, the idea emerged that minimal brain damage to the brain could cause hyperactive behaviour. Researcher Alfred Strauss considered the symptom of hyperactivity to be a sufficient diagnostic sign of underlying brain damage. Further, Strauss argued that hyperactivity could be able to distinguish between brain-injured and non-brain-injured children.
Criticism began to arise over the necessity of the brain to be damaged in hyperactive children. Laufer and colleagues proposed that there may be a functional disturbance in the brain, rather than damage. Clements (1966) specified the three symptoms of an inability to control attention, impulsivity, and motor function. Thus, the three core symptoms characterizing ADHD of inattention, impulsivity, and hyperactivity were established with the definition of minimal brain dysfunction.
From the 1960s, criticism of minimal brain dysfunction arose. It was criticised for being too general. Minimal brain dysfunction was later replaced with more specific labels such as hyperactivity, learning disability, dyslexia, or language disorder. In the Diagnostic and Statistical Manual of Mental Disorders (DSM) 2nd edition (a manual used to diagnose most mental illnesses), hyperactivity was referred to as being “characterised by over-activity, restlessness, distractibility, and short attention span” (APA, 1968).
In the 1970s, the focus shifted more to the issues of attention, rather than hyperactivity. This shift was aided by an influential paper by Virginia Douglas in 1972. As a result, the publication of DSM-III in 1980 saw the introduction of a new disorder – attention deficit disorder with or without hyperactivity. The DSM-III contained three separate symptom lists for inattention, impulsivity, and hyperactivity. In the DSM-III-R (APA, 1987) attention deficit hyperactivity disorder became a single disorder, with all symptoms combined into a single list. The DSM-IV (APA, 1994) divided ADHD into three subtypes: (i) ADHD – inattentive subtype, (ii) ADHD – hyperactive subtype, and (iii) ADHD – combined subtype. It was also in the 1990s that ADHD was recognised as not being an exclusively childhood disorder which disappeared with age. It was instead recognised that ADHD was a chronic persistent disorder remaining into adulthood in many cases. However, it was only with the release of DSM-V (APA, 2013) that ADHD was officially recognised in adults.
How does our research fit in?
The UCD Neuropsychology Lab is currently conducting a study looking at potential early markers for ADHD. We are particularly interested in sleep, sensory processing, and family functioning and their relation with ADHD. For our study, we are recruiting children under 6 who have a parent or older sibling with a diagnosis of ADHD. If you would like to take part, you can click on the ‘How Do I Take Part?’ tab at the top of the screen!