The functional brain networks that underlie Early Stone Age tool manufacture

• Published in: Nature human behaviour Vol. 1; no. 6; p. 0102
• Main Authors: Putt, Shelby S., Wijeakumar, Sobanawartiny, Franciscus, Robert G., Spencer, John P.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group 01.06.2017
• Subjects: Action planning; Brain activity; Cognition; Cortex; Humans; Neuroimaging; Short term memory; Spectrum analysis; Stone Age
• ISSN: 2397-3374; 2397-3374
• DOI: 10.1038/s41562-017-0102

After 800,000 years of making simple Oldowan tools, early humans began manufacturing Acheulian handaxes around 1.75 million years ago. This advance is hypothesized to reflect an evolutionary change in hominin cognition and language abilities. We used a neuroarchaeology approach to investigate this hypothesis, recording brain activity using functional near-infrared spectroscopy as modern human participants learned to make Oldowan and Acheulian stone tools in either a verbal or nonverbal training context. Here we show that Acheulian tool production requires the integration of visual, auditory and sensorimotor information in the middle and superior temporal cortex, the guidance of visual working memory representations in the ventral precentral gyrus, and higher-order action planning via the supplementary motor area, activating a brain network that is also involved in modern piano playing. The right analogue to Broca’s area—which has linked tool manufacture and language in prior work1,2—was only engaged during verbal training. Acheulian toolmaking, therefore, may have more evolutionary ties to playing Mozart than quoting Shakespeare.The advent of Acheulian stone-tool technologies 1.75 million years ago is likely to have coincided with changes in early human cognition. Using functional near-infrared spectroscopy neuroimaging, modern Acheulian toolmakers are shown to use the same brain network as is involved in playing the piano.