We present a systematic and qualitative review of academic literature on early conceptual development (0–24 months of age), with an emphasis on methodological aspects. The final sample of our review included 281 studies reported in 115 articles. The main aims of the article were four: first, to organise studies into sets according to methodological similarities and differences; second, to elaborate on the methodological procedures that characterise each set; third, to circumscribe the empirical indicators that different sets of studies consider as proof of the existence of concepts in early childhood; last, to identify methodological limitations and to propose possible ways to overcome them. We grouped the studies into five sets: preference and habituation experiments, category extension tasks, object sorting tasks, sequential touching tasks and object examination tasks. In the “Results” section, we review the core features of each set of studies. In the “Discussion” and “Conclusions” sections, we describe, for one thing, the most relevant methodological shortcomings. We end by arguing that a situated, semiotic and pragmatic perspective that emphasises the importance of ecological validity could open up new avenues of research to better understand the development of concepts in early childhood.

中文翻译：

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幼儿期分类和概念思维的发展：方法和局限性。


我们对早期概念发展（0-24 个月大）的学术文献进行了系统和定性的回顾，重点是方法论方面。我们审查的最终样本包括 115 篇文章中报告的 281 项研究。文章的主要目的有四个：第一，根据方法论的异同将研究组织成组；其次，详细阐述每组特征的方法程序；第三，限制不同研究认为证明幼儿期概念存在的经验指标；最后，确定方法上的局限性并提出克服这些局限性的可能方法。我们将研究分为五组：偏好和习惯实验、类别扩展任务、物体分类任务、顺序触摸任务和物体检查任务。在“结果”部分，我们回顾了每组研究的核心特征。在“讨论”和“结论”部分中，我们一方面描述了最相关的方法论缺陷。最后我们认为，强调生态有效性重要性的情境、符号学和实用主义视角可以开辟新的研究途径，以更好地理解幼儿期概念的发展。