Esquirol and Diagnosis in Mental Retardation
Around the beginning of the nineteenth century,
many physicians had begun to perceive the difference
between mental retardation (then called idiocy)
and mental illness (often referred to as
dementia). J. E. D. Esquirol (1772–1840) was the
first to formalize the difference in writing. His
diagnostic breakthrough was noting that mental retardation
was a lifelong developmental phenomenon
whereas mental illness usually had a more
abrupt onset in adulthood. He thought that mental
retardation was incurable, whereas mental illness
might show improvement (Esquirol, 1845/1838).
Esquirol placed great emphasis upon language
skills in the diagnosis of mental retardation. This may
offer a partial explanation as to why Binet’s later tests
and the modern-day descendents from them are so
heavily loaded on linguistic abilities. After all, the
original use of the Binet scales was, in the main, to
identify children with mental retardation who would
not likely profit from ordinary schooling.
Esquirol also proposed the first classification
system in mental retardation and it should be no
surprise that language skills were the main diagnostic
criteria. He recognized three levels of mental
retardation: (1) those using short phrases,
(2) those using only monosyllables, and (3) those
with cries only, no speech. Apparently, Esquirol did
not recognize what we would now call mild mental
retardation, instead providing criteria for the equivalents
of the modern-day classifications of moderate,
severe, and profound mental retardation.