The Results of Repeated Mental Reëxamination of 639 Feeble-minded over a period of Ten Years.

Abstract

F. " Binet and Simon's system for measuring the intelligence of children" Journ. Psycho-Asthenics, 1911. 8 See Kuhlmann, F. " A revision of the Binet-Simon system for measuring the intelligence of children." Journ. Psycho-Asthenics, Monograph Supplements, Sept., 1912.* See Kuhlmann, F. " Some results of examining a thousand public school children with a revision of the Binet-Simon tests." Journ.

Our changing concept of intelligence.

“…For example, losses by individuals residing in institutions for the feeble-minded have consistently been found. The loss over one year is so small as to be negligible, usually reported as about one and one-half to two points (3,5,6).…”

Mental development of children.

“…Several studies deal primarily with feebleminded children. Kuhlmann (69) reported results on 639 cases, mostly feebleminded, examined two to five times, each of which showed a decrease in I. Q. with age with a greater decrease for the higher grades than for the lower. Doll, (32) presenting data based on at least five retests of feebleminded subjects, concludes that the feebleminded subjects reach their limit of mental growth before fifteen years of life age.…”

"Environment and the IQ"

“…Among the more recent studies are those by Chipman (11), Arthur (1), Prouty (59), Hilden (25), Davenport and Minogue (15), and Woodall (94), though in the last-named the yearly decrease for a group of 497 subjects was only 0.45 IQ point. Kuhlmann (39), whose study in 1921 deserves mention because of its comprehensiveness, reported an average yearly decrease of 2.19 points for borderline cases, 1.21 for morons, 1.04 for imbeciles, and .37 for idiots. Hilden (25) found a decrease after one year of 1.8 points, and after six years of 7.8 points.…”