The empirical investigation of cognitive processes in infants is hampered by the limited development of their body and motor control skills. Novel gaze-contingent paradigms where infants control their environment with their eyes offer a solution to this problem since the control of gaze develops very early. Recently such a paradigm has been used to investigate the learning of anticipatory behaviour of 6/8-months-old infants in an experiment where gazing at a "button" causes the appearance of an interesting image. The experiment shows that infants learn in few trials to "press the button" with their gaze and, remarkably, to anticipate the image appearance in only few trials. The experiment raises two questions: (a) what are the processes supporting such fast learning? (b) why does the anticipatory behaviour emerge? This paper presents a bio-inspired model that puts forward possible answers to these questions. The model consists of: (a) a bottom-up attention component for scene saliency detection; (b) a top-down attention component that uses reinforcement learning (RL) to learn to control gaze based on current foveal stimuli; (c) a dynamic field map that decides where to look based on the bottom-up and top-down information. The results show that the model is indeed capable of learning to perform anticipatory saccades in few trials. The analysis of the system shows that this fast learning is due to the guidance exerted by the bottom-up component on the learning process of the top-down component. Moreover, it shows that the anticipatory behaviour can be explained in terms of the action of the top-down component exploiting the learned spatial relations of stimuli in an anticipatory fashion. Overall, the results indicate that the model has the essential features to theoretically frame, interpret, and design experiments using gaze contingency.
A Bio-Inspired Attention Model of Anticipation in Gaze-Contingency Experiments with Infants
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IEEE International Conference on Development and Learning-EpiRob 2012 (ICDL-EpiRob-2012), San Diego, CA, 7-9 November 2012