Interference effects in early infant visual memory and categorisation: A connectionist model

Young infants show unexplained asymmetries in the exclusivity of categories formed on the basis of visually presented stimuli. They will also, on some occasions display retroactive interference when shown a succession of visual stimuli whereas on other occasions no interference is found. We describe a connectionist model that shows similar exclusivity asymmetries when categorising the same stimuli presented to the infants. The model predicts asymmetric retroactive interference when learning two categories sequentially. The asymmetry can be explained in terms of an associative learning mechanism, distributed internal representations, and the statistics of the feature distributions in the stimuli. A study of 3to 4-month-olds’ sequential acquisition of Cat and Dog categories also reveals asymmetric retroactive interference, thereby corroborating the model’s prediction. This model exemplifies how unrelated domains can be bridged by shifting the onus of research away from a descriptive competence level to a process level at which the mechanisms that underlie performance on different tasks are described. Finally, the model suggests that catastrophic interference is an integral part of early cognition and should be viewed as a necessary component of any model wishing to account for performance across the whole range of human cognition.