Make Your Child Smarter

Discrepancy in IQ scores

Q: My daughter has had an IQ test at 5 and came out in the 96th percentile she then had an IQ TEST at 8.5 yrs and her IQ had fallen to the 84 percentile. She has been diagnosed with dyslexia and auditory processing disorder. Is it possible to have such a huge variance in the IQ TEST results?

She was tested with WPPSI-R and WISC -IV I am concerned she has add as her processing speed is very low at 53 percentile. She was sick when the test was administered - she was recovering from pneumonia. She is performing really poorly at school and it not even at an average level. She has suffered from chronic tonsillitis and anemia for a good 12 months too. Are you able to shed any light on this!!

A: At a glance, it does appear to be a rather significant drop but as one notes the circumstances, for instance, 3.5 year gap, her learning difficulties which may be more pronounced, and her condition when the test was administered indeed justify the results.

Processing speed generally refers to the varying speed with which individuals are able to perform cognitive activities such as the recognition of simple stimuli. Higher speed in cognitive processing usually allows more information to be acquired in a shorter time span enabling the individual to absorb and master materials of higher levels. Above average individuals usually have high processing speed, thus enabling them to reach developmental milestones ahead of their age mates. In layman's terms, the brain is working faster which is viewed as superior intelligence, hence the difference in human intelligence.

Having said that, there is more to intelligence than speed of processing, which is the reason most IQ test use a combination of factors to assess intellectual skills. According to the WISC, processing speed measures children's abilities to focus attention and quickly scan, discriminate between, and sequentially order visual information. It requires persistence and planning ability, but is sensitive to motivation, difficulty working under a time pressure, and motor coordination too. Cultural factors seem to have little impact on it. It is related to reading performance and development too. It is related to Working Memory in that increased processing speed can decrease the load placed on working memory, while decreased processing speed can impair the effectiveness of working memory.

Due to your daughter's medical condition, these may have been interfered with. Perhaps you need to see a pediatrician to help with her medical issues and that may be the underlying concern that needs immediate attention. You did mention ADD. Apparently, lower processing speed scores could indicate such concerns. There are children with ADHD who have IQ scores in the gifted range, yet rather low processing speed. This is definitely a concern and I'm afraid I can only advise you to seek medical opinion, and once diagnosed with any medical related problem; perhaps an intervention strategy can be planned to help her in school. I believe she needs an individualized program in school. Hope the above helped shed some light on your concerns. Best wishes.

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