Towards Emerging Multimodal Cognitive Representations from Neural Self-Organization

The integration of multisensory information plays a crucial role in autonomous robotics. In this work, we investigate how robust multimodal representations can naturally develop in a self-organized manner from co-occurring multisensory inputs. We propose a hierarchical learning architecture with growing self-organizing neural networks for learning human actions from audiovisual inputs. Associative links between unimodal representations are incrementally learned by a semi-supervised algorithm with bidirectional connectivity that takes into account inherent spatiotemporal dynamics of the input. Experiments on a dataset of 10 full-body actions show that our architecture is able to learn action-word mappings without the need of segmenting training samples for ground-truth labelling. Instead, multimodal representations of actions are obtained using the co-activation of action features from video sequences and labels from automatic speech recognition. Promising experimental results encourage the extension of our architecture in several directions. Keywords—Human action recognition, multimodal integration, self-organizing networks.