Prefrontal cortex activation supports the emergence of early stone age toolmaking skill

Trends toward encephalization and technological complexity ∼1.8 million years ago may signify cognitive development in the genus Homo. Using functional near-infrared spectroscopy, we measured relative brain activity of 33 human subjects at three different points as they learned to make replicative Oldowan and Acheulian Early Stone Age tools. Here we show that the more complex early Acheulian industry recruits left dorsolateral prefrontal cortex when skills related to this task are first being learned. Individuals with increased activity in this area are the most proficient at the Acheulian task. The Oldowan task, on the other hand, transitions to automatic processing in less than 4 h of training. Individuals with increased sensorimotor activity demonstrate the most skill at this task. We argue that enhanced working memory abilities received positive selection in response to technological needs during the early Pleistocene, setting Homo on the path to becoming human

Cognitive Demands of Lower Paleolithic Toolmaking

Stone tools provide some of the most abundant, continuous, and high resolution evidence of behavioral change over human evolution, but their implications for cognitive evolution have remained unclear. We investigated the neurophysiological demands of stone toolmaking by training modern subjects in known Paleolithic methods (“Oldowan”, “Acheulean”) and collecting structural and functional brain imaging data as they made technical judgments (outcome prediction, strategic appropriateness) about planned actions on partially completed tools. Results show that this task affected neural activity and functional connectivity in dorsal prefrontal cortex, that effect magnitude correlated with the frequency of correct strategic judgments, and that the frequency of correct strategic judgments was predictive of success in Acheulean, but not Oldowan, toolmaking. This corroborates hypothesized cognitive control demands of Acheulean toolmaking, specifically including information monitoring and manipulation functions attributed to the central executive of working memory. More broadly, it develops empirical methods for assessing the differential cognitive demands of Paleolithic technologies, and expands the scope of evolutionary hypotheses that can be tested using the available archaeological record

The Effects of Training on Action Observation: A Neuroarchaeological Investigation using EEG

Like all organisms, humans have evolved from their ancestors. This process of evolution has not only changed the physical appearance of humans but also shaped their cognitive mechanisms and abilities. Over time, humans have developed various cognitive abilities in response to specific events during evolution. For example, living in more densely populated groups may have led humans to develop a cognitive mechanism to monitor the actions of others, thereby increasing their chance of survival. Cognitive neuroscience seeks to answer questions about the cognitive processes that humans possess today as a result of evolution. To better understand how these processes function, interdisciplinary studies are needed. Here, we introduce a relatively new field that combines neuroscience and archeology called neuroarcheology, which can provide insight into human cognition. On the basis of this interdisiclinary perspective, we focus on action observation and report the results of our experiment that utilized EEG to investigate whether toolmaking training caused differential brain activity between groups during an action observation task. Our preliminary findings show subtle differences between the experimental group (trained) and the control group. These results can serve as a valuable reference point for future studies in this area.Like all organisms, humans have evolved from their ancestors. This process of evolution has not only changed the physical appearance of humans but also shaped their cognitive mechanisms and abilities. Over time, humans have developed various cognitive abilities in response to specific events during evolution. For example, living in more densely populated groups may have led humans to develop a cognitive mechanism to monitor the actions of others, thereby increasing their chance of survival. Cognitive neuroscience seeks to answer questions about the cognitive processes that humans possess today as a result of evolution. To better understand how these processes function, interdisciplinary studies are needed. Here, we introduce a relatively new field that combines neuroscience and archeology called neuroarcheology, which can provide insight into human cognition. On the basis of this interdisiclinary perspective, we focus on action observation and report the results of our experiment that utilized EEG to investigate whether toolmaking training caused differential brain activity between groups during an action observation task. Our preliminary findings show subtle differences between the experimental group (trained) and the control group. These results can serve as a valuable reference point for future studies in this area

Neural correlates of perceiving and interpreting engraved prehistoric patterns as human production: Effect of archaeological expertise

It has been suggested that engraved abstract patterns dating from the Middle and Lower Palaeolithic served as means of representation and communication. Identifying the brain regions involved in visual processing of these engravings can provide insights into their function. In this study, brain activity was measured during perception of the earliest known Palaeolithic engraved patterns and compared to natural patterns mimicking human-made engravings. Participants were asked to categorise marks as being intentionally made by humans or due to natural processes (e.g. erosion, root etching). To simulate the putative familiarity of our ancestors with the marks, the responses of expert archaeologists and control participants were compared, allowing characterisation of the effect of previous knowledge on both behaviour and brain activity in perception of the marks. Besides a set of regions common to both groups and involved in visual analysis and decision-making, the experts exhibited greater activity in the inferior part of the lateral occipital cortex, ventral occipitotemporal cortex, and medial thalamic regions. These results are consistent with those reported in visual expertise studies, and confirm the importance of the integrative visual areas in the perception of the earliest abstract engravings. The attribution of a natural rather than human origin to the marks elicited greater activity in the salience network in both groups, reflecting the uncertainty and ambiguity in the perception of, and decision-making for, natural patterns. The activation of the salience network might also be related to the process at work in the attribution of an intention to the marks. The primary visual area was not specifically involved in the visual processing of engravings, which argued against its central role in the emergence of engraving production.publishedVersio

Early knapping techniques do not necessitate cultural transmission

Early stone tool production, or knapping, techniques are claimed to be the earliest evidence for cultural transmis-sion in the human lineage. Previous experimental studies have trained human participants to knap in conditions involving opportunities for cultural transmission. Subsequent knapping was then interpreted as evidence for a necessity of the provided cultural transmission opportunities for these techniques. However, a valid necessity claim requires showing that individual learning alone cannot lead to early knapping techniques. Here, we tested human participants (N = 28) in cultural isolation for the individual learning of early knapping techniques by providing them with relevant raw materials and a puzzle task as motivation. Twenty-five participants were technique naïve according to posttest questionnaires, yet they individually learned early knapping techniques, therewith producing and using core and flake tools. Early knapping techniques thus do not necessitate cultural transmission of know-how and could likewise have been individually derived among premodern hominins

Evidence, Inference and Human Evolution: Essays in the Philosophy of Cognitive Archaeology

The promise of cognitive archaeology is considerable: the discipline can potentially outline a chronology of human cognitive evolution, and offer insights into the dynamics involved. However, the field faces two major methodological hurdles. First, it is a historical science; one that requires running inferences from the archaeological record to the cognitive capacities of our hominin ancestors. Second, it requires synthesising work from a disparate range of disciplines, including archaeology, cognitive science, and evolutionary biology. The overall goal of this thesis is to demonstrate how philosophers of biology can help meet these challenges using the philosophical tools of analysis and synthesis. Chapters 1-3 analyse various inferential strategies employed by cognitive archaeologists, and identify problems for those strategies. These problems relate to theoretical diversity, cultural variation, and the explanation of historical phenomena with multiple causal inputs. Chapters 1-3 also propose solutions to these problems. Together, they contribute to the growing literature aimed at developing a reliable inferential framework for cognitive archaeology. Chapters 4-6 synthesise work from archaeology, cognitive science and evolutionary biology in order to produce first-order claims about the evolution of particular cognitive capacities. These capacities include technical cognition, language, and theory of mind. Chapters 4-6 align with a growing trend amongst philosophers of biology for unifying theoretical work across disciplinary boundaries. Producing a robust science of human evolution is a daunting challenge. In this thesis, I aim to highlight the role both cognitive archaeology and philosophy of biology can play in addressing this challenge. I demonstrate that interdisciplinary work is essential to understanding our evolutionary origins

The measurement, evolution, and neural representation of action grammars of human behavior

Human behaviors from toolmaking to language are thought to rely on a uniquely evolved capacity for hierarchical action sequencing. Testing this idea will require objective, generalizable methods for measuring the structural complexity of real-world behavior. Here we present a data-driven approach for extracting action grammars from basic ethograms, exemplified with respect to the evolutionarily relevant behavior of stone toolmaking. We analyzed sequences from the experimental replication of ~ 2.5 Mya Oldowan vs. ~ 0.5 Mya Acheulean tools, finding that, while using the same “alphabet” of elementary actions, Acheulean sequences are quantifiably more complex and Oldowan grammars are a subset of Acheulean grammars. We illustrate the utility of our complexity measures by re-analyzing data from an fMRI study of stone toolmaking to identify brain responses to structural complexity. Beyond specific implications regarding the co-evolution of language and technology, this exercise illustrates the general applicability of our method to investigate naturalistic human behavior and cognition

The Identity Model: a theory to access visual display and hominin cogntition within the Palaeolithic

The question of the development of hominin social communication is a subject that is of continual interest to researchers of human development, behaviour and cognition. Language development has in particular been related to studies in cognitive capacity and the ability for mind reading, often termed a theory of mind (ToM). There has only really been one successful attempt to correlate a cognitive scale of complexity that incorporates a ToM, in the form of intentionality orders, to the archaeological record and hominin phylogeny, and that is the Social Brain Hypothesis (Aiello and Dunbar 1993; Dunbar 1996; 1998a; 2003; 2004). However, a method is still lacking that allows a correlation of the orders of intentionality (and by inference a ToM and language development) to the archaeological signatures that represent the physical expression of hominin behaviour. This paper is primarily concerned with introducing a new theoretical framework – termed the identity model – which suggests a heuristic correlation between a scale of cognitive acuity, hominin behaviour and the archaeology. The aim of this paper is to refresh debates corresponding to hominin behaviour by illustrating a different and innovative approach in relating the Palaeolithic record to cognitive development, and not to make definitive statements

A proof of concept for machine learning-based virtual knapping using neural networks

Prehistoric stone tools are an important source of evidence for the study of human behavioural and cognitive evolution. Archaeologists use insights from the experimental replication of lithics to understand phenomena such as the behaviours and cognitive capacities required to manufacture them. However, such experiments can require large amounts of time and raw materials, and achieving sufficient control of key variables can be difficult. A computer program able to accurately simulate stone tool production would make lithic experimentation faster, more accessible, reproducible, less biased, and may lead to reliable insights into the factors that structure the archaeological record. We present here a proof of concept for a machine learning-based virtual knapping framework capable of quickly and accurately predicting flake removals from 3D cores using a conditional adversarial neural network (CGAN). We programmatically generated a testing dataset of standardised 3D cores with flakes knapped from them. After training, the CGAN accurately predicted the length, volume, width, and shape of these flake removals using the intact core surface information alone. This demonstrates the feasibility of machine learning for investigating lithic production virtually. With a larger training sample and validation against archaeological data, virtual knapping could enable fast, cheap, and highly-reproducible virtual lithic experimentation