Cognitive Neural Mechanism And Development Characteristics Of The Groupitizing Strategies In Numerosity Perception

Numerosity perception involves humans’ cognitive ability to extract numerical information from various stimuli,forming a crucial foundation for understanding the world and processing information.Grouping strategies,known as "groupitizing," encompass the organization of objects into sets or categories during numerosity perception processes.This facilitates rapid and effective numerosity estimation,particularly in situations with short presentation times and numerous quantities.Groupitizing combines the advantages of subitizing and counting,influencing individual arithmetic abilities.However,previous studies have often overlooked the influence of perceptual grouping cues,both intrinsic and extrinsic,on groupitizing strategies in numerosity perception.They have also failed to comprehensively explore the cognitive and neural mechanisms underlying groupitizing strategies across multiple dimensions.To deepen our understanding of this cognitive phenomenon,this study adopts the "A theory of magnitude"(ATOM)as its theoretical framework to systematically investigate groupitizing strategies in visual numerosity perception.The ATOM posits a shared neural basis among time,space,and quantity,linked through the concept of motion.This linkage relies on the brain’s shared neural systems involved in encoding temporal,spatial,and numerical information,all of which involve motion,such as objects moving in space,the passage of time,and changes in quantity.By converting different types of motion information into shared neural representations,the brain can establish connections between quantity,time,and space.Therefore,this study integrates the ATOM and comprehensively utilizes behavioral and f MRI techniques to explore the influences of different dimensions of magnitude systems on groupitizing strategies in numerosity perception and investigate their characteristics in individual developmental processes.The research comprises four studies,totaling seven experiments,conducted from the dimensions of space,time,and motion.The study 1 investigates the influence of spatial grouping cues on the cognitive neural mechanisms underlying numerosity perception of groupitizing,utilizing spatial dot array stimuli.This study comprises two experiments: Experiment 1 examines the impact of intrinsic and extrinsic grouping cues on numerosity perception at the behavioral level.Participants engage in a numerosity estimation task with dot arrays.The findings reveal that participants effectively employ grouping strategies for numerosity perception,with extrinsic grouping cues demonstrating a more pronounced grouping effect compared to intrinsic cues.Experiment 2 employs f MRI technology to further elucidate the neural basis of these strategies.It reveals that under grouping conditions,there is heightened activation in brain regions implicated in numerical calculation,such as the left superior parietal sulcus,angular gyrus,and superior frontal gyrus.This activation exhibits left hemisphere lateralization,indicating participants’ inclination towards employing mental arithmetic for numerosity perception under grouping conditions.Furthermore,extrinsic grouping cues elicit more robust activation in the middle frontal gyrus and inferior temporal gyrus,providing neural evidence that extrinsic grouping cues operate as topological invariants,conferring unique advantages in perceptual processing.Study 2 investigates the impact of temporal grouping cues on the cognitive neural mechanisms underlying numerosity perception of groupitizing,utilizing sequentially presented sequence stimuli.This study comprises two experiments: Experiment 3compares the differences in intrinsic and extrinsic grouping cues under two conditions of stimulus onset asynchrony(SOA)at the behavioral level.It finds that participants utilize grouping strategies for numerosity perception in the temporal dimension,with extrinsic grouping cues consistently resulting in higher perceptual accuracy compared to intrinsic cues.Experiment 4 utilizes f MRI technology to explore the neural correlates of these strategies.It reveals that both grouping and no-grouping conditions activate brain regions associated with numerosity perception,with the grouping condition additionally activating calculation-related brain regions such as the bilateral superior frontal gyrus.Furthermore,the no-grouping condition exhibits a right hemisphere lateralization advantage.This study validates,at both behavioral and neural levels,that temporal grouping effects involve mental arithmetic and that the no-grouping condition demonstrates right hemisphere lateralization advantages.These findings suggest that temporal dimension numerosity processing may necessitate the coordinated action of attentional mechanisms.The study 3 grounded in the sensorimotor numerosity system(SNS),utilizes a motion adaptation paradigm to investigate numerosity perception from the perspective of the motion dimension.This study comprises two experiments: Experiment 5 requires participants to adapt to either high-frequency or low-frequency finger tapping tasks before completing a subsequent numerosity estimation task.This aims to explore the relationship between proprioceptive sensorimotor adaptation and the groupitizing.In Experiment 6,participants are instructed to observe and adapt to point arrays displaying either high-speed or low-speed motion.This experiment aims to investigate the relationship between visual motion adaptation and the groupitizing.The findings reveal that adaptation effects are observed in both conditions: high-frequency adaptation(rapid tapping or observing rapid motion points)results in numerosity underestimation,while low-frequency adaptation(slow tapping or observing slow motion points)leads to overestimation.However,both adaptation effects are attenuated under grouping conditions,indicating the presence of grouping effects in the motion dimension and the mutual influence between adaptation effects and grouping effects.Study 4 focuses on elementary school children from grades one to six,aiming to explore the developmental characteristics of numerosity perception on groupitizing(Experiment 7).The results indicate that children’s numerosity perception abilities gradually improve with age.First-grade students do not yet utilize grouping strategies for numerosity perception,while students from second grade onwards begin to exhibit significant grouping advantages.This suggests that the development of numerosity perception grouping strategies in school-age children reaches a critical stage by the second grade.Additionally,among school-age children,extrinsic grouping cues demonstrate stronger grouping effects compared to intrinsic grouping cues.This indicates that regardless of whether they are adults or children,extrinsic grouping cues consistently exhibit a relative advantage,significantly impacting numerosity perception grouping strategies.In summary,this study examines the cognitive neural mechanisms and developmental characteristics of numerosity perception in groupitizing from the perspectives of spatial,temporal,and motion aspects of ATOM,with perceptual grouping as the entry point.The results reveal that grouping effects exist in numerosity perception across spatial,temporal,and motion dimensions,and extrinsic grouping cues significantly influence the groupitizing of numerosity perception.Developmental research indicates that groupitizing gradually improve with age,with a critical period of development occurring around the second grade of primary school.This study provides a foundation for further understanding the essence of numerosity perception on groupitizing and offers a basis for achieving efficient mathematical learning.