Developmental changes in head‐circumference and mental‐performance growth rates: A test of epstein's phrenoblysis hypothesis

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presented discrepant findings regarding the presence of stages in brain and cognitive maturation, as described in Piagetian theory. This article questions whether their variables (e.g., skull circumference and global mental test scores) are appropriate indices from which to make such conclusions. Evidence from direct brain measurements (e.g., the quantitative electroencephalogram [QEEG]) and other neurobiological indices provides stronger support for the conclusion that regional brain maturation exhibits growth spurts and plateaus. The specific neuropsychological functions represented by regional QEEG maturation data give a composite picture of brain growth that is consistent with Piagetian theory.

mentioning

confidence: 99%

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confidence: 99%

Stages of brain and cognitive maturation.

Hudspeth¹,

Pribram²

1990

188

“…Mental-Educational Growth Periodicity I am still not persuaded that group or individual developmental profiles of growth rates of mental age or IQ as assessed by commonly used standardized instruments clearly follow the hypothesized periodicity (McCall et al, 1983). Group IQ growth rate patterns do not (McCall, 1988a), and whereas individual IQ and mental age profiles show inflections at 5-6, 10-12, and perhaps at 14-15 years of age {McCall et al, 1973;McCall et al, 1983), not all of these points are at hypothesized peak periods and some children display increases and some display decreases at these ages. Epstein (1990) criticized my (McCall, 1988a) review of this literature on several methodological grounds.…”

Section: Brain Growth Periodicitymentioning

confidence: 99%

“…880-883) showing periodicity in the developmental patterns of quantified electroencephalograms (QEEG) for four areas of the brain validate the phrenoblysis hypothesis of Epstein (Epstein, 1974a(Epstein, , 1974b and thereby render irrelevant the disagreements between Epstein (1990, this issue, pp. 875-879) and me (McCall, 1988a;McCall, Meyers, Hartman, & Roche, 1983). Actually, however, I believe those data make it more, rather than less, necessary to consider some of the issues in this debate before curricula are changed and educational decisions are made for children on the basis of this concept.Briefly, Epstein (1974aEpstein ( , 1974b proposed that the brain grows in spurts (with peaks occurring between 3 and 10 months and between 2 and 4 years, 6 and 8 years, 10 and 12-13 years, and 14 and 16-17 years of age), that mental performance also grows in spurts that peak at the same ages, and that the spurts in brain growth are functionally related to the spurts in mental growth.…”

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confidence: 99%

The neuroscience of education: More research is needed before application.

McCall¹

1990

Self Cite

In reply to Epstein (1990, this issue), McCall maintains that although the recent quantitative EEG data reviewed by Hudspeth and Pribram (1990, this issue) show growth spurts conforming to Epstein's phrenoblysis theory, more research, especially longitudinal and individual difference studies, is needed before application of the theory to educational practice is warranted. Furthermore, gross indices of brain growth (e.g., head circumference) and general mental performance (e.g., mental age or IQ) do not consistently follow the theory, and research should focus on more specific measures. Finally, few data exist demonstrating that brain growth periodization relates to practical mental and educational skills and performance in the same individual children. Such research is needed before alterations in educational curricula are considered and researched.There is nothing like a good set of data to dissolve academic arguments, and it appears that the data reviewed by Hudspeth and Pribram (1990, this issue, pp. 880-883) showing periodicity in the developmental patterns of quantified electroencephalograms (QEEG) for four areas of the brain validate the phrenoblysis hypothesis of Epstein (Epstein, 1974a(Epstein, , 1974b and thereby render irrelevant the disagreements between Epstein (1990, this issue, pp. 875-879) and me (McCall, 1988a;McCall, Meyers, Hartman, & Roche, 1983). Actually, however, I believe those data make it more, rather than less, necessary to consider some of the issues in this debate before curricula are changed and educational decisions are made for children on the basis of this concept.Briefly, Epstein (1974aEpstein ( , 1974b proposed that the brain grows in spurts (with peaks occurring between 3 and 10 months and between 2 and 4 years, 6 and 8 years, 10 and 12-13 years, and 14 and 16-17 years of age), that mental performance also grows in spurts that peak at the same ages, and that the spurts in brain growth are functionally related to the spurts in mental growth. He proposed that children are more likely to learn new material during the spurts than during the plateaus of growth and that perhaps new educational material and interventions (e.g., Head Start) should be introduced during the high-growth periods.In one of the few direct, comprehensive tests of this theory, McCall et al. (1983) analyzed a longitudinal sample assessed between 2.5 and 17 years of age and found minimum support for the hypothesized peaks in either head circumference or general mental performance growth rates and no evidence for their relationship in the entire sample or within individuals. I (McCall, 1988a) then reviewed and reanalyzed the mental performance growth data from the several studies that Epstein (1974b) had cited in support of his theory and found minimum evidence for the hypothesis, certainly not adequate to encourage application of the concept to educational settings.

“…The individual studies are followed by the presentation of two summary analyses determined across selected studies and analogous to summary composites presented by Epstein. Last, I review a more recent study (McCall et al, 1983) that was not available to Epstein in the 1970s but that is the most direct and appropriate test of the theory.…”

Section: General Principles and Proceduresmentioning

confidence: 99%

Growth periodization in mental test performance.

McCall¹

1988

Self Cite

Epstein proposed that the brain and mental ability grow in spurts, specifically at 3-10 months and 2-4, 6-8,10-12 or 13, and 14-16 or 17 years of age, and that new concepts and skills should be taught primarily during the spurts, not during the plateaus. The mental test data cited by Epstein to support his theory are reanalyzed in this article. Only two studies provided any statistically significant relation with the theory. Tn one, the age changes were partly confounded with differences in test forms. In the other study, the pattern of means ran counter to theoretical predictions. A summary of the age distribution of increments and decrements in mental growth rates across studies did not reveal consistent or substantial age changes, and the age period that most consistently contained accelerated growth across studies had been hypothesized to be a period of slow, not rapid, growth.