Abstract

The book “The Pervasiveness of Ensemble Perception” is part of the Cambridge Elements series on perception. It effectively fulfills the objectives of Cambridge Elements by merging the advantageous aspects of journals and books, resulting in a scholarly discussion on a focused topic and a reliable reference source. With its comprehensive content, it can be regarded as an extended, original, peer-reviewed paper. Simultaneously, it serves as a convenient reference book for ensemble researchers, providing valuable insights whenever needed. This publication is particularly suitable for specialized graduate courses in vision science and caters to researchers of all levels who are interested in ensemble perception and its practical applications.
To begin with, it is important to explore the concept of ensemble perception. The book defines ensemble perception as the rapid process of perceiving and representing statistical summaries of sets of similar items. Numerous examples of such similar items can be found in our surroundings, such as buildings in a city, a cluster of cars, a gathering of people, evergreen trees in a forest, or the autumn leaves of a gingko tree. Corbett and colleagues propose that our visual perception initially involves extracting statistical summaries and subsequently recognizing individual objects when required. For instance, when encountering a group of people, we first observe the overall mood of the group before attending to the facial expressions of each individual. Due to the inherent limitations of our visual system, we do not focus on every individual facial expression unless it becomes necessary. Instead, we initially perceive and form an impression of the overall mood of the crowd.
This book is “not just average review (p. 3).” Its clever subtitle aptly captures the key message of the book: ensemble processing is an integral aspect of visual information processing at all stages. Furthermore, it surpasses the realm of an average review by offering extensive and comprehensive coverage of topics related to ensemble perception. Despite the breadth of coverage, the topics are skillfully organized, showcasing the authors’ meticulous efforts. I applaud their dedication and express my gratitude for extensive coverage and the organization. Consequently, I firmly believe that this book will serve as an excellent foundation for future research, as is the authors’ intention.
Corbett et al. commence their exploration by providing a concise history of ensemble perception research. This historical background is particularly valuable as it offers insights into the origins of ensemble perception, predating its modern inception marked by Ariely's work in 2001 (Ariely, 2001). Subsequently, in chapter 2, the authors conduct a comprehensive review of prior findings in ensemble perception. They meticulously analyze studies encompassing various stimuli, processing stages, statistical descriptors, and modalities. Additionally, they elucidate how ensemble perception operates across spatial and temporal dimensions. In chapter 3, they delve into current issues within ensemble perception research. These include canonical computation, sampling issues, the nature of representations, contributions from constituents to statistical summaries, and the automaticity of ensemble perception. The authors provide a balanced and detailed overview of the field, while also proposing areas that warrant further investigation. Notably, they endeavor to explain the findings and issues within the framework of reverse hierarchy theory (Hochstein & Ahissar, 2002) and the population response model (Utochkin et al., 2023). Given that all three authors are esteemed experts in ensemble perception at different stages of their careers, it comes as no surprise that their review of topics and issues is comprehensive, thorough, and well-balanced. Chapter 4 focuses on the neural mechanisms underlying ensemble perception. As research in this area is still in its nascent stages, it is understandable that the chapter is comparably short.
Finally, in chapter 5, Corbett et al. present a compelling argument for ensemble perception as a foundational process for various crucial visual functions. These functions include rapid gist extraction, noise cancellation, hierarchical encoding, categorization, outlier detection, perceptual learning, maintaining stability, and smart perception. Furthermore, the authors highlight the potential applications of ensemble coding, such as data visualization, decision-making, and the detection of rare targets like tumors or weapons. Noise cancellation through averaging, for example, can be employed to enhance the precision of decision-making processes. By averaging across multiple independent judgments, the accuracy of grading can be significantly improved (Kahneman et al., 2021). This final chapter adeptly presents the implications and practical applications of ensemble perception.
Ensemble coding appears to function as a canonical computation across all stages of visual processing. The breadth and organization of topics addressed in this book are truly remarkable, while the synthesis of reverse hierarchy theory and population response model presents a compelling narrative. I highly recommend this book to individuals with an interest in this subject, irrespective of their level of expertise. This book offers fundamental concepts and theories in ensemble perception, making it suitable for novice researchers. Moreover, it explores the latest trends and serves as a valuable resource for experts, offering them starting points for further exploration.
It is worth mentioning that the price of the book may be somewhat high given its page count. However, considering its value as reference material, opting for the eBook version might be more advantageous. The eBook format enables easy searching for specific information, thereby enhancing its value as a reliable reference source.
