Human-Technology Interaction is a multidisciplinary field that refers to the communication between the human user and different kind of computer systems. The current paper presents some deep-technology approaches that are contributing to technology-computer interaction in the context of dementia, and that have been tested in Galicia or the north of Portugal. Specifically, different user tests are described within the AFAGA or SCMRA facilities, testing virtual reality, convocational agents and personalized multimedia systems. Immersive virtual reality appeared to be a feasible, safe and enjoyable technology for per- sons with dementia. Intelligent conversational agents appear to be able to detect cognitive decline in older people through machine learning algorithms, using both spoken and written exchange. Personalized multimedia systems can be used in promoting personalized care in old adults with dementia through the digitization of stories, integrating personal preferences and significant aspects of the personal history in an electronic support. Through usability studies, we have observed that participation and co-design improve the development of assistive technologies for people with dementia. The studies presented highlight the need for longer interventions, larger samples and more sensitive measures.