Are jigsaw puzzle skills 'spared' in persons with Prader-Willi syndrome?

BACKGROUND This three-part study examines previous clinical impressions that people with Prader-Willi syndrome have unusual jigsaw puzzle and word search skills. RESULTS Children with Prader-Willi syndrome showed relative strengths on standardized visual-spatial tasks (Object Assembly, Triangles, VMI) in that their scores were significantly higher than age- and IQ-matched peers with mixed mental retardation, but below those of age-matched normal children with average IQs. In striking contrast, children with Prader-Willi syndrome scored on par with normal peers on word searches, and they far outperformed them on the jigsaw puzzles, placing more than twice as many pieces as the typically-developing group. Within Prader-Willi syndrome, puzzle proficiency was not predicted by age, IQ, gender, degree of obesity, or obsessive-compulsive symptoms, but by genetic subtypes of this disorder. CONCLUSIONS Findings are discussed in relation to splinter skills in autism, and to cases with autism and chromosome 15 anomalies that include the Prader-Willi region.