I've recently stumbled upon the book "The Semiotic Engineering of Human-Computer Interaction" and I'm going through it now.
It offers a thorough foundation of Human Computer Interaction as a discipline, following an alternate approach which tries to complement usual HCI practice.
Semiotics is "the study of signs and signification", so it views HCI as an ongoing communication process between the software designer and its user - using the particular software artifacts as the form of messages, and describing the whole process with the established vocabulary and insight of the semiotic science. So far it has added some perspective to my other readings on this subject. In particular it gives a sound justification to those techniques often considered less scientific because of their lack of hard data (heuristic evaluation, user personas, scenarios & storytelling...)
This article from Celeste Lyn Paul, HCI Foundations: Theoretical Frameworks talks about other theoretical frameworks.
HCI Foundations: Theoretical Frameworks