The Flynn effect in neuropsychological assessment.

The Flynn effect refers to the rise in IQ throughout the 20th century. This study examined whether the Flynn effect has also elevated performance on neuropsychological tests. A search of published norms revealed five tests with appropriate normative data available for comparison. These tests were the Trail-Making Test (TMT), Symbol Digit Modalities Test (SDMT), Boston Naming Test, Finger Tapping, and Grooved Pegboard. Results indicated a strong Flynn effect for Parts A and B of the TMT and a probable Flynn effect for the oral SDMT. No Flynn effect was evident for the other tests. Implications for clinical assessment are discussed.

Age-related IQ decline is reduced markedly after adjustment for the Flynn effect.

Twenty-year-olds outperform 70-year-olds by as much as 2.3 standard deviations (35 IQ points) on subtests of the Wechsler Adult Intelligence Scale (WAIS). We show that most of the difference can be attributed to an intergenerational rise in IQ known as the Flynn effect. Normative data from different versions of the WAIS enabled us to estimate the degree to which the Flynn effect, rather than age-related decline, contributes to differences between 20- and 70-year-olds. The Flynn effect accounted for 38-67% of the apparent age-related decline on 6 of the 11 subtests. On the other 5 subtests, all of which are categorized as verbal, the Flynn effect was larger than the age-group difference. For these verbal subtests, the Flynn effect masked a modest increase in ability as individuals grow older. Overall, the Flynn effect accounted for at least 85% of the disparity between 20- and 70-year-olds.

Cognitive effects of pegylated interferon in individuals with primary brain tumors.

Cognitive changes associated with interferon treatment include impaired verbal memory, attention, processing speed, and executive functioning. Pegylated interferon is a relatively new, long-lasting form of interferon alpha, but data regarding its cognitive effects in brain tumor patients are limited. Participants in this study were 35 primary brain tumor patients who received pegylated interferon at tumor recurrence. A neuropsychological battery assessed verbal memory, executive functioning, attention, information processing speed, and language functioning. Individual growth curve analyses were used to estimate cognitive change throughout treatment with interferon. Results revealed performance declined on a task of psychomotor speed and upper extremity dexterity. Although decline in a few tests was found, its degree may have been reduced because individuals were tested after tumor recurrence where a substantial amount of cognitive change had already potentially occurred due to surgery, radiation therapy, and chemotherapy. Thus, participants may not have been starting at their baseline cognitive status and the potential neurotoxic effects of interferon may have been obscured by prior treatments. An alternative explanation, however, is that treatment with pegylated interferon did not produce further impairment and patients experienced stability in their cognitive functioning.