Using Attentive Focus to Discover Action Ontologies from Perception.
Amitabha Mukerjee · 2009
The word “symbol”, as it is used in logic and computational theory, is considerably different from its usage in cognitive linguistics and in everyday life. Formal approaches that define symbols in terms of other symbols ultimately need to be grounded in perceptualmotor terms. Based on cognitive evidence that the earliest action structures may be learned from perception alone, we propose to use attentive focus to identify the agents participating in an action, map the characteristics of their interaction, and ultimately discover actions as clusters in perceptuo-temporal space. We demonstrate its applicability by learning actions from simple 2D image sequences, and then demonstrate the learned predicate by recognizing 3D actions. This mapping, which also identifies the objects involved in the interaction, informs us on the argument structure of the verb, and may help guide syntax. Ontologies in such systems are learned as different granularities in the clustering space; action hierarchies emerge as membership relations between actions. 1