Encyclopedia of Autism Spectrum Disorders

2013 Edition
| Editors: Fred R. Volkmar

Processing Speed Index

  • Timothy Soto
Reference work entry
DOI: https://doi.org/10.1007/978-1-4419-1698-3_246



Processing speed refers to the speed of cognitive processes and response output. The Processing Speed Index (PSI) is one of four indices that make up the full scale intelligence quotient (FSIQ) derived from The Wechsler Adult Intelligence Scale-4th edition (WAIS-IV) and The Wechsler Intelligence Scale for Children-4th edition (WISC-IV), primary standardized clinical instruments used to measure intelligence. The tasks included in the scales that comprise the PSI, (Coding, Symbol Search), are timed and require attending to visual material, visual perception and organization, visual scanning, and hand-eye coordination. Performance on the Coding subtest also requires paired associative learning. Anxiety and fine motor problems may interfere with performance on the PSI. Coding, in particular, which requires copying simple shapes, may be affected by motor output problems. This tends to be an area of relative weakness for children with ASD...

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References and Readings

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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Clinical PsychologyUniversity of Massachusetts BostonBostonUSA