  Gaze reflects how humans process visual scenes and is therefore increasingly
used in computer vision systems. Previous works demonstrated the potential of
gaze for object-centric tasks, such as object localization and recognition, but
it remains unclear if gaze can also be beneficial for scene-centric tasks, such
as image captioning. We present a new perspective on gaze-assisted image
captioning by studying the interplay between human gaze and the attention
mechanism of deep neural networks. Using a public large-scale gaze dataset, we
first assess the relationship between state-of-the-art object and scene
recognition models, bottom-up visual saliency, and human gaze. We then propose
a novel split attention model for image captioning. Our model integrates human
gaze information into an attention-based long short-term memory architecture,
and allows the algorithm to allocate attention selectively to both fixated and
non-fixated image regions. Through evaluation on the COCO/SALICON datasets we
show that our method improves image captioning performance and that gaze can
complement machine attention for semantic scene understanding tasks.
