How Prediction Based on Sequence Detection in the Cerebellum Led to the Origins of Stone Tools, Language, and Culture and, Thereby, to the Rise of Homo sapiens

Abstract

This article extends Leiner et al.'s watershed position that cerebellar mechanisms played prominent roles in the evolution of the manipulation and refinement of ideas and language. First it is shown how cerebellar mechanism of sequence-detection may lead to the foundational learning of a predictive working memory in the infant. Second, it is argued how this same cerebellar mechanism may have led to the adaptive selection toward the progressively predictive phonological loop in the evolution of working memory of pre-humans. Within these contexts, cerebellar sequence detection is then applied to an analysis of leading anthropologists Stout and Hecht's cerebral cortex-based explanation of the evolution of culture and language through the repetitious rigors of stone-tool knapping. It is argued that Stout and Hecht's focus on the roles of areas of the brain's cerebral cortex is seriously lacking, because it can be readily shown that cerebellar sequence detection importantly (perhaps predominantly) provides more fundamental explanations for the origins of culture and language. It is shown that the cerebellum does this in the following ways: (1) through prediction-enhancing silent speech in working memory, (2) through prediction in observational learning, and (3) through prediction leading to accuracy in stone-tool knapping. It is concluded, in agreement with Leiner et al. that the more recently proposed mechanism of cerebellar sequence-detection has played a prominent role in the evolution of culture, language, and stone-tool technology, the earmarks of Homo sapiens. It is further concluded that through these same mechanisms the cerebellum continues to play a prominent role in the relentless advancement of culture.

Keywords: acheulean artifacts; cerebellar internal models; cerebellar sequence detection; cerebellum; language evolution; phonological loop; working memory.

Figure 1

Mandler (1992a); Mandler's (1992b, 2008); Mandler (2012)) conceptual primitives—collectively, the infant's unconscious “primitive physics.” That is, the conceptual primitives represent the meaning of images and thereby establish the foundations of cause-and-effect relationships in the infant's visual-spatial working memory, notably the depicted categories of animacy, causality, and agency. It is argued that these conceptual primitives depict optimized predictive/anticipatory cerebellar internal models. It is not suggested that the conceptual primitives are constructed in the brain in this graphic form, but rather in the form of cerebellar microcomplexes as described by Ito (1997, 2008). Figure prepared by Kimberly Weathers-Moe Illustrations (kweathers10@mywhitworth.edu).

Figure 2

Capuchin Stone-Tool Use: A generalized sequence of stone-tool nut-cracking actions (A) driven by an imagined goal in visual-spatial working memory in capuchins. The stone-tool actions of the capuchin serve as a pre-human model for hand axe manufacture and use by early hominins between a million and a half and 150,000 years ago. Following the internal representation (imagined goal) of a prospective goal (I), the orderly series of actions (A) is mediated by cerebro-cerebellar loops. It is argued that the cerebro-cerebellar decomposition and blending of visual and vocal components of skill routines and strategies across the series of “If no—repeat” sub-routines of actions led to syntax (including the force component, i.e., verb forms) in working memory's phonological loop during language evolution. Photo of capuchin engaged in nut-cracking (lower left) obtained through Dr. Dorothy Fragaszy, Professor and Chair, Behavioral and Brain Sciences Program, University of Georgia and printed with permission of Barth W. Wright, EthoCebus Project (http://www.ip.usp.br/site/ethocebus). Figure prepared by Kimberly Weathers-Moe Illustrations (kweathers10@mywhitworth.edu).