Concept maps or mind maps visually represent relationships of different concepts. In research, they can help you make connections between ideas. You can use them as you are formulating your research question, as you are reading a complex text, and when you are creating a literature review. See the video and examples below.
Credit: Austin Kleon. A map I drew of John Berger’s Ways of Seeing in 2008. Tumblr post. April 14, 2016. http://tumblr.austinkleon.com/post/142802684061#notes