Michael Shayer

Integration/differentiation of mental processes is major mechanism of development. Developmental theories ascribe intellectual development to it. In psychometric theory, Spearman’s law of diminishing returns postulates that increasing g allows increasing differentiation of cognitive abilities, because increased mental power allows variable investment in domain-specific learning. Empirical evidence has been inconsistent so far, with some studies supporting and others contradicting this mechanism. This state of affairs is due to a developmental phenomenon: Both differentiation and strengthening of relations between specific processes and g may happen but these changes are phase-specific and ability-specific, depending upon the developmental priorities in the formation of g in each phase. We present eight studies covering the age span from 4 to 85 years in support of this phenomenon. Using new powerful modeling methods we showed that differentiation and binding of mental processes in g occurs in cycles. Specific processes intertwine with g at the beginning of cycles when they are integrated into it; when well established, these processes may vary with increasing g, reflecting its higher flexibility. Representational knowledge, inductive inference and awareness of it, and grasp of logical constraints framing inference are the major markers of g, first intertwining with in their respective cycles and differentiating later during the periods of 2–6, 7–11, and 11–20 years, respectively. The implications of these findings for an overarching cognitive developmental/differential theory of human mind are discussed.

This article summarizes a comprehensive theory of intellectual organization and growth. The theory specifies a common core of processes (Abstraction, representational Alignment, and Cognizance, i.e., AACog) underlying inference and meaning making. AACog develops over four reconceptualization cycles (episodic representations, representations, rule-based concepts, and principle-based concepts starting at birth, 2, 6, and 11 years, respectively) with two phases in each (production of new mental units and alignment). This sequence relates with changes in processing efficiency and working memory in overlapping cycles such that relations with efficiency are high in the production phases and relations with WM are high in the alignment phases over all cycles. Reconceptualization is self-propelled because AACog continuously generates new mental content expressed in representations of increasing inclusiveness and resolution. Each cycle culminates into insight about the cycle’s representations and underlying inferential processes that is expressed into executive programs of increasing flexibility. Learning addressed to this insight accelerates the course of reconceptualization. Individual differences in intellectual growth are related to both the state of this core and its interaction with different cognitively primary domains (e.g., categorical, quantitative, spatial cognition, etc.). The relations between this theory and brain research are discussed.

Cet article résume une théorie intégrative de la structure de l’intelligence et de son développement. Cette théorie précise l’existence d’un noyau commun de processus (Abstraction, Ajustement représentatif et prise de conscience Cognitive, c’est-à-dire AACog) qui sous-tend les inférences et la construction du sens. AACog se développe selon quatre cycles de reconceptualisation (représentations épisodiques, représentations, concepts fondés sur des règles, concepts fondés sur des principes) qui débutent respectivement à la naissance puis à 2, 6, et 11 ans et qui comportent chacun deux phases : la création d’unités mentales nouvelles et leur ajustement. Cette séquence est en relation avec l’efficience du traitement cognitif et avec la mémoire de travail selon des cycles imbriqués. Ainsi, à chaque cycle de AACog, les relations avec l’efficience cognitive sont fortes dans la phase de création d’unités tandis que les relations avec la mémoire de travail sont fortes dans la phase d’ajustement. La reconceptualisation est auto-alimentée dans la mesure où AACog engendre continuellement de nouveaux contenus mentaux qui s’expriment dans des représentations d’intégration et de résolution croissantes. Chaque cycle aboutit à mieux concevoir les représentations du même cycle ainsi que les processus inférentiels sous-jacents qui s’expriment dans des programmes exécutifs de flexibilité croissante. Les apprentissages qui portent sur ces prises de conscience accélèrent le rythme de la reconceptualisation. Les différences individuelles dans le développement cognitif sont reliés à la fois aux propriétés du noyau cognitif et à ses interactions avec les différents domaines cognitifs primaires (par ex. catégorisation, quantification, connaissances spatiales, etc.). Les relations entre cette théorie et les recherches sur le cerveau sont discutées.