The incapacity of attending with a necessary degree of constancy to any one object (Sir Alexander Crichton, 1763–1856)
The first example of a disorder that appears to be similar to ADHD was given by Sir Alexander Crichton in 1798. Crichton was a Scottish physician who was born in Edinburgh in 1763. In 1785, he received his M.D. from the University of Leiden, The Netherlands (Palmer and Finger 2001; Tansey 1984). He then decided “to undertake a European medical tour” (Tansey 1984, p. 243) and practiced in hospitals in Paris, Stuttgart and Vienna (Tansey 1984). In his clinical practice, Crichton observed many cases of insanity and became increasingly interested in mental illness (Palmer and Finger 2001). In 1798, he published “An inquiry into the nature and origin of mental derangement: comprehending a concise system of the physiology and pathology of the human mind and a history of the passions and their effects”. In this work of three books, he demonstrated observations of clinical cases of mental illness (Palmer and Finger 2001). Up until the end of the eighteenth century, when Crichton published his inquiry, it was uncommon to focus on mental issues from a physiological or medical perspective (Palmer and Finger 2001). Crichton mentioned that at the time there were only two other authors who had “written fully on the subject of Mental Diseases” (Crichton 1798, pp. ii–iii, cited by Palmer and Finger 2001).
The second chapter of book II “On Attention and its Diseases” is of special interest to the present subject. Crichton begins this chapter with a definition of attention: “When any object of external sense, or of thought, occupies the mind in such a degree that a person does not receive a clear perception from any other one, he is said to attend to it” (Crichton 1798, reprint p. 200). Crichton emphasizes that the intensity of healthy attention varies within a normal range both between individuals and even within a person at different times (Crichton 1798). A distraction of attention does not necessarily have to be pathological, e.g. mental stimuli, volition, or education can have a great impact on healthy attention (Crichton 1798). Crichton distinguishes two possibilities of abnormal inattention as the oppositional poles of pathologically increased or decreased “sensibility of the nerves” (Crichton 1798):
The morbid alterations to which attention is subject, may all be reduced under the two following heads:
First. The incapacity of attending with a necessary degree of constancy to any one object.
Second. A total suspension of its effects on the brain.
The incapacity of attending with a necessary degree of constancy to any one object, almost always arises from an unnatural or morbid sensibility of the nerves, by which means this faculty is incessantly withdrawn from one impression to another. It may be either born with a person, or it may be the effect of accidental diseases.
When born with a person it becomes evident at a very early period of life, and has a very bad effect, inasmuch as it renders him incapable of attending with constancy to any one object of education. But it seldom is in so great a degree as totally to impede all instruction; and what is very fortunate, it is generally diminished with age. (Crichton, 1798, reprint p. 203)
Citation:(https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3000907/)