Vol. 11, No. 2, 2005 Page 7
Transnationally adopted children who become delinquents are much more likely to exhibit cognitive or neuropsychological deficits than their adopted peers who do not become delinquents, according to a recent Swedish study.
Anna Elmund et al. compared two groups of adopted children. The children, ranging in age from 9 to 21, were originally from other European countries, South America, or Asia. Of the group, 20 were delinquents and 21 were not. In both groups, the majority of subjects were male. The two groups did not differ significantly as to age, sex, or country of origin.
The researchers say the adopted delinquents had significantly lower IQs than the controls and scored more poorly on several other cognitive measures, even when the researchers adjusted for their age when they arrived in their adoptive homes. The mean full-scale IQ of the delinquents was about 85, while the mean for non-delinquents was nearly 100. While both groups had lower- than-average scores for arithmetic skills, the delinquents again did worse than the non-delinquents. Moreover, Elmund et al. say, the delinquents' cognitive profiles were highly irregular, with a higher- than-typical number of subtest scores falling above or below the mean in many cases.
No differences between the two groups were seen on the Wisconsin Card Sorting Test, a measure of abstract thinking and the ability to shift cognitive strategies when required. However, in the Tower of London test, the delinquents needed significantly more time to complete the easiest steps, an indication of impaired planning skills. They were less successful at other steps as well, but this difference did not reach statistical significance.
Parent questionnaires indicated that five of the delinquents, but only one of the non-delinquents, qualified for a diagnosis of attention deficit hyperactivity disorder (ADHD). Also, 30 percent of the delinquents, but only 14 percent of the controls, were left- handed. Left-handedness is typically genetic, but can also indicate subtle brain damage.
"Cognitive and neuropsychological functioning in transnationally adopted juvenile delinquents," Anna Elmund, Lennart Melin, Anne- Liis von Knorring, Lemm Proos, and Torsten Tuvemo, Acta Paediatrica, Vol. 93, No. 11, November 2004, 1507-13. Address: Anna Elmund, Department of Women's and Children's Health, University Hospital, SE-751 85 Uppsala, Sweden, anna.elmund@kbh.uu.se.