Due to their characteristics, Alzheimer's dementia (AD) and fronto-temporal dementia (FTD) coincide, from a psychosocial perspective, in the direct and significant impact on the members of the social environment of those who experience them. Objective: to identify and describe the role of social support networks from the information available in the literature, emphasizing the caregiver and considering in them the processes of social cognition, only from conceptual analysis and empirical evidence available from previous research on these two types of dementia. Method: documentary and systematic review of investigations from specialized databases. Results: there were differences in the level of impact that both types of dementia have on the social support network, including the caregiver, depending on the type of dementia and on the availability of resources by the network. Likewise, it was observed that there is a documentary gap in the analysis about the participation of social cognition in the relationship between the members of the network and those suffering from any of these dementias. From this study, arise questions that suggest further description of these types of dementia should be made.