European Journal of Pediatrics

, Volume 154, Issue 9, pp 739–746 | Cite as

Information processing in patients with early and continuously-treated phenylketonuria

  • B. A. Stemerdink
  • J. J. van der Meere
  • M. W. van der Molen
  • A. F. Kalverboer
  • M. M. T. Hendrikx
  • J. Huisman
  • L. W. A. van der Schot
  • F. M. E. Slijper
  • F. J. van Spronsen
  • P. H. Verkerk
Original Paper Metabolic Diseases


A total of 33 patients with early and continuously-treated phenylketonuria (PKU) between 7 and 16 years of age and 33 matched controls participated in a study examining perceptual, central, and response-related mechanisms of information processing. The specific mechanisms studied were: perceptual filtering, memory search, response selection, response execution, and motor presetting. In addition, groups were compared on mean intelligence level and task oriented behaviour. The performance of the PKU patients practically matched that of the controls on all three tasks, suggesting that PKU patients who are continuously maintained on a well-controlled phenylalanine-restricted diet are not impaired in the elementary mechanisms of information processing. Furthermore, groups did not differ in mean IQ or task-oriented behaviour.

Key words

Phenylketonuria Information processing Dietary treatment 







intelligence quotient


inter-stimulus interval


Revised Wechsler Intelligence Scale for Children


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Copyright information

© Springer-Verlag 1995

Authors and Affiliations

  • B. A. Stemerdink
    • 1
  • J. J. van der Meere
    • 1
  • M. W. van der Molen
    • 2
  • A. F. Kalverboer
    • 1
  • M. M. T. Hendrikx
    • 3
  • J. Huisman
    • 4
  • L. W. A. van der Schot
    • 5
  • F. M. E. Slijper
    • 6
  • F. J. van Spronsen
    • 7
  • P. H. Verkerk
    • 8
  1. 1.Department of Developmental and Experimental Clinical PsychologyState University GroningenGroningenThe Netherlands
  2. 2.Department of PsychologyUniversity of AmsterdamAmsterdamThe Netherlands
  3. 3.Department of Child PsychiatryUniversity Hospital AMCAmsterdamThe Netherlands
  4. 4.Department of Medical PsychologyFree University HospitalAmsterdamThe Netherlands
  5. 5.Department of Child PsychologyUniversity Hospital St. RadboudNijmegenThe Netherlands
  6. 6.Department of Child and Adolescent PsychiatrySophia Childrens HospitalRotterdamThe Netherlands
  7. 7.Beatrix Child ClinicUniversity Hospital of GroningenThe Netherlands
  8. 8.TNO Institute of Preventive Health CareLeidenThe Netherlands

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