@article{BreitBrunnerPreckel2020,
  author    = {Breit, Moritz Lion and Brunner, Martin and Preckel, Franzis},
  title     = {General intelligence and specific cognitive abilities in adolescence},
  series = {Developmental psychology},
  volume    = {56},
  journal   = {Developmental psychology},
  number    = {2},
  publisher = {American Psychological Association},
  address   = {Washington},
  issn      = {0012-1649},
  doi       = {10.1037/dev0000876},
  pages     = {364 -- 384},
  year      = {2020},
  abstract  = {Differentiation of intelligence refers to changes in the structure of intelligence that depend on individuals' level of general cognitive ability (ability differentiation hypothesis) or age (developmental differentiation hypothesis). The present article aimed to investigate ability differentiation, developmental differentiation, and their interaction with nonlinear factor analytic models in 2 studies. Study 1 was comprised of a nationally representative sample of 7,127 U.S. students (49.4\% female; M-age = 14.51, SD = 1.42, range = 12.08-17.00) who completed the computerized adaptive version of the Armed Service Vocational Aptitude Battery. Study 2 analyzed the norming sample of the Berlin Intelligence Structure Test with 1,506 German students (44\% female; M-age = 14.54, SD = 1.35, range = 10.00-18.42). Results of Study 1 supported the ability differentiation hypothesis but not the developmental differentiation hypothesis. Rather, the findings pointed to age-dedifferentiation (i.e., higher correlations between different abilities with increasing age). There was evidence for an interaction between age and ability differentiation, with greater ability differentiation found for older adolescents. Study 2 provided little evidence for ability differentiation but largely replicated the findings for age dedifferentiation and the interaction between age and ability differentiation. The present results provide insight into the complex dynamics underlying the development of intelligence structure during adolescence. Implications for the assessment of intelligence are discussed.},
  language  = {en}
}
@article{BreitBrunnerPreckel2021,
  author    = {Breit, Moritz Lion and Brunner, Martin and Preckel, Franzis},
  title     = {Age and ability differentiation in children},
  series = {Developmental psychology},
  volume    = {57},
  journal   = {Developmental psychology},
  number    = {3},
  publisher = {American Psychological Association},
  address   = {Richmond, Va. [u.a.]},
  issn      = {0012-1649},
  doi       = {10.1037/dev0001147},
  pages     = {325 -- 346},
  year      = {2021},
  abstract  = {Differentiation hypotheses concern changes in the structural organization of cognitive abilities that depend on the level of general intelligence (ability differentiation) or age (developmental differentiation). Part 1 of this article presents a review of the literature on ability and developmental differentiation effects in children, revealing the need for studies that examine both effects simultaneously in this age group with appropriate statistical methods. Part 2 presents an empirical study in which nonlinear factor analytic models were applied to the standardization sample (N = 2,619 German elementary schoolchildren; 48\% female; age: M = 8.8 years, SD = 1.2, range 6-12 years) of the THINK 1-4 intelligence test to investigate ability differentiation, developmental differentiation, and their interaction. The sample was nationally representative regarding age, gender, urbanization, and geographic location of residence but not regarding parents' education and migration background (overrepresentation of children with more educated parents, underrepresentation of children with migration background). The results showed no consistent evidence for the presence of differentiation effects or their interaction. Instead, different patterns were observed for figural, numerical, and verbal reasoning. Implications for the construction of intelligence tests, the assessment of intelligence in children, and for theories of cognitive development are discussed.},
  language  = {en}
}