HCI. Not that this narrows it down much considering the HCII 2013 conference proceedings consists of 29 volumes (http://www.hcii2013.org/proceedings). However, if you want to look at cutting edge topics in human behavior and design (and by design I mean everything from software to "Secure, Usable Biometric Authentication Systems" to "E-Inclusion as the Next Challenge for Sustainable Consumption" and a host of other topics, that would be the place to start. For one thing, part of the HCII joint conferences included the 2nd annual "Design, User Experience, and Usability" conference, the proceedings of which are volumes 9 through 12 of the HCII proceedings published by Springer. For another, the actual "Human-Computer Interaction" conference (rather than the joint conferences) gets pride of place in terms of volume ordering, and within the HCI-proper volumes the first one somewhat defines the entire event and the sets the tone for the thousands upon thousands of pages published subsequently; the 2013 first HCI volume was Human-Computer Interaction: Human-Centred Design Approaches, Methods, Tools and Environments. Topics in that volume alone range from models of experience engineering to "culture-aware robots". All volumes are available electronically via SpringerLink as well as in hardcopy.