Understanding object categorisation through development: the influence of movement and other developmental heuristics on adult cognition

Abstract

Developmental psychologists and cognitive neuroscientists have asked the same fundamental questions about how perceptual information is transformed into a complex, conceptual understanding of the world. Yet, we know very little about their intersection. Is neural object processing in children similar to adults? How do childhood heuristics influence adult cognition? Using methods, theories, and findings from both fields, this thesis investigates how development of categorical processing is reflected in the brain and behaviour of adults and children. Chapters 2, 3, and 4 investigated how our adult conceptual system reflects developmental processes. Adults classified words and images according to aliveness, rated their movement characteristics and their similarity. Electroencephalography was recorded during aliveness and movement judgements. Items violating associations between movement and aliveness, plants, and moving natural things, were harder to classify. Capacity for movement was represented in patterns of brain activity, with an initial identification of movement speed, followed by more abstract characteristics like how independent the motion is. These findings suggest movement provides important clues to object identity. Chapters 5 and 6 investigated how developmental processes are reflected in the brain. In Chapter 5, we recorded EEG while adults classified animals, plants, and minerals that were camouflaged. Visual features that were informative for predicting object category were correlated with brain activity, and used to judge similarity. In Chapter 6, we directly compared neural and behavioural categorisation in adults and 4-year-old children, using EEG and an odd-one-out similarity task. Behavioural similarity judgements were similar across age groups. Together, the findings suggest that similarity to humans, based on capacity for agentive movement, influences judgements of aliveness and neural representations of objects in both adults and children.