Making Drawings Speak Through Mathematical Metrics.

Figurative drawing is a skill that takes time to learn, and it evolves during different childhood phases that begin with scribbling and end with representational drawing. Between these phases, it is difficult to assess when and how children demonstrate intentions and representativeness in their drawings. The marks produced are increasingly goal-oriented and efficient as the child's skills progress from scribbles to figurative drawings. Pre-figurative activities provide an opportunity to focus on drawing processes. We applied fourteen metrics to two different datasets (N = 65 and N = 344) to better understand the intentional and representational processes behind drawing, and combined these metrics using principal component analysis (PCA) in different biologically significant dimensions. Three dimensions were identified: efficiency based on spatial metrics, diversity with color metrics, and temporal sequentiality. The metrics at play in each dimension are similar for both datasets, and PCA explains 77% of the variance in both datasets. Gender had no effect, but age influenced all three dimensions differently. These analyses for instance differentiate scribbles by children from those drawn by adults. The three dimensions highlighted by this study provide a better understanding of the emergence of intentions and representativeness in drawings. We discussed the perspectives of such findings in comparative psychology and evolutionary anthropology.

Draw yourself: How culture influences drawings by children between the ages of two and fifteen.

The place children live strongly influence how they develop their behavior, this is also true for pictorial expression. This study is based on 958 self-portraits drawn by children aged 2-15 years old from 35 countries across 5 continents. A total of 13 variables were extracted of each drawing allowing us to investigate the differences of individuals and environment representations in these drawings. We used a principal component analysis to understand how drawing characteristics can be combined in pictorial concepts. We analyzed the effect of age, gender, socioeconomic, and cultural factors in terms of complexity and inclusion of social (human figures) and physical (element from Nature and man-made elements) environments, their frequencies, size, and proportions of these elements on each drawing. Our results confirm the existence of cultural variations and the influence of age on self-portrait patterns. We also observed an influence of physical and socio-cultural contexts through the level of urbanization and the degree of individualism of the countries, which have affected the complexity, content and representation of human figures in the drawings studied.

New indices to characterize drawing behavior in humans (Homo sapiens) and chimpanzees (Pan troglodytes).

Techniques used in cave art suggest that drawing skills emerged long before the oldest known representative human productions (44,000 years BC). This study seeks to improve our knowledge of the evolutionary origins and the ontogenetic development of drawing behavior by studying drawings of humans (N = 178, 3- to 10-year-old children and adults) and chimpanzees (N = 5). Drawings were characterized with an innovative index based on spatial measures which provides the degree of efficiency for the lines that are drawn. Results showed that this index was lowest in chimpanzees, increased and reached its maximum between 5-year-old and 10-year-old children and decreased in adults, whose drawing efficiency was reduced by the addition of details. Drawings of chimpanzees are not random suggesting that their movements are constrained by cognitive or locomotor aspect and we cannot conclude to the absence of representativeness. We also used indices based on colors and time and asked children about what they drew. These indices can be considered relevant tools to improve our understanding of drawing development and evolution in hominids.

Drawing in nonhuman primates: What we know and what remains to be investigated.

For over a century now, a number of researchers have explored the evolutionary emergence of mark-making and drawing behaviors through studies in monkeys and apes, and particularly in chimpanzees. Their observations and results remain relevant to this day and underline the interest of this question and the questions that remain to be answered. The present review begins by retracing the historical timeline of this specific and challenging topic from the earliest anecdotal evidence to the first systematic studies in the 1930s. We then describe how the research became more empirical through the use of stimulus figures, the examination of color choices, or even exploring outline-making processes. We discuss the use of touch screens in the 1990s, which enriched our knowledge by providing an opportunity for data collection and innovative analysis. Finally, we underline several key points that are of importance for future investigations into the mark-making process in nonhuman primates. (PsycInfo Database Record (c) 2021 APA, all rights reserved).