Tool Use and Brain Evolution: How Cognitive Advances Shaped Human Development

New research links early tool use to critical changes in brain activity, paving the way for human biocultural evolution.

Tools as a Catalyst for Evolution

The ability to create and use tools is a hallmark of human evolution. A groundbreaking study by researchers from the University of Tübingen, led by Dr. Alexandros Karakostis, provides fresh insights into how changes in brain function enabled early humans to wield tools with precision. Published in Scientific Reports¹, the study highlights how cognitive advancements and motor planning associated with tool use were instrumental in shaping the trajectory of human biocultural evolution.

A researcher demonstrates which tasks the participants were asked to perform during the experiment—here in the planning phase: on the left, making precise cuts in leather; on the right, cracking nuts using stone tools. Credit: University of Tübingen

Investigating Early Human Tool Use

Dr. Karakostis and his team sought to understand the cognitive developments that allowed early humans to transition from simple tool use, observed in other primates, to the complex and precise use of tools that defines our species.

“Technological innovations were crucial for human evolution,” Karakostis explains. “We are interested in what cognitive developments were necessary for the use of relatively simple stone tools—and where humans and other primates differ in their abilities.”

To explore these questions, the researchers designed an experiment involving human participants replicating two types of tool use:

1. Cracking nuts with stones, a behavior also observed in some primates.

2. Cutting leather using chipped stone tools, an activity unique to humans.

By observing these tasks, the team aimed to map the distinct patterns of brain activity associated with each type of tool use.

The Role of Brain Activity in Tool Use

The study used electroencephalogram (EEG) recordings to monitor participants’ brain activity as they completed the tasks. The findings revealed significant differences in the cognitive processes required for nut-cracking versus cutting tasks.

“Our study provides empirical evidence to support distinct patterns of brain activity during different behaviors and stages of early hominin tool use,” said Simona Affinito, Ph.D. student and first author of the study.

Cutting tasks, which involve precise manipulation of chipped stone tools, required more extensive brain activity compared to the relatively simpler task of nut-cracking.

H2: The Cognitive Leap: Precision Tool Use

The researchers found that cutting tools activated the frontoparietal regions of the brain, particularly during the aiming stage. These regions are essential for planning and executing complex motor actions.

“The involvement of the frontoparietal regions highlights the importance of these brain areas in planning motor actions,” Affinito explained.

Nut-cracking, while requiring cognitive effort, engaged less extensive brain activity. This contrast underscores the higher cognitive demands of precision tool use, a critical step in enabling early humans to manipulate their environment in unprecedented ways.

“These differences implicitly highlight the cognitive performance required for precise tool-using tasks,” Karakostis noted. “They likely enabled early humans to appropriate and shape their environment in a way that was not possible before.”

Tools, Cognition, and Human Evolution

The study illuminates how the use of chipped stone tools marked a turning point in human evolution. While nut-cracking has been observed in primates such as chimpanzees and capuchins, the habitual use of cutting tools is unique to humans and signals a profound leap in cognitive abilities.

The researchers replicated stone tools resembling those found in early archaeological records to ensure their findings were rooted in realistic conditions. The brain activity patterns associated with cutting tasks provide strong empirical evidence of the cognitive demands and motor planning required for this behavior.

Implications for Future Research

The findings lay the groundwork for further exploration of the cognitive prerequisites for technological innovation. Understanding how early humans developed the capacity for precise tool use may shed light on the broader cognitive and cultural shifts that define human evolution.

“The new study creates a basis for further research into the cognitive prerequisites for human technological progress,” Karakostis emphasized.

By linking specific brain regions to the stages of tool use, researchers can delve deeper into how technological advancements and cognitive evolution co-evolved in early human populations.

The Brain-Tool Connection

The evolution of the human brain and the ability to use tools with precision are deeply interconnected. This study demonstrates how advancements in cognitive and motor planning capabilities were pivotal in shaping the biocultural evolution of early humans. As researchers continue to explore the intricate relationship between brain function and technological innovation, they uncover not only the roots of humanity’s unique capabilities but also the profound impact of tools on human development.

1. Affinito, S., Eteson, B., Cáceres, L. T., Moos, E. T., & Karakostis, F. A. (2024). Exploring the cognitive underpinnings of early hominin stone tool use through an experimental EEG approach. Scientific Reports, 14(1). https://doi.org/10.1038/s41598-024-77452-0