I want it to be clear that I do not think that I have the all the answers about learning styles theory and pedagogy. I wrote about this earlier in the year here. Learning styles theory is an extremely complex subject that covers psychology, sociology, neuroscience, epistemology, and pedagogy. Notice all the soft sciences in this list. That said, in my own practice in special education in the k-12 realm, my work as a tutor and tutor trainer, and as an English teacher has benefitted tremendously from these tools. I have seen students who were tested as auditory learners begin to use recorders in the classroom and I have watched their lives turn around, but that is not research. The learning styles theories as they stand cover too much ground and are too broad to determine (at this point in time) solid empirical testing. Many of the theories are too simplistic to cover the complexity of the human mind. The research questions in some cases have to be narrowed. Researchers have to continue to define and test the theory, and explore - there is a lot to be done. There have been numerous attempts - many, to my way of thinking, have been successful. What happens though is that contra learning styles educators simply change the definition of learning styles to dismiss the conclusions of the research or weaken the argument by narrowly define what the theory should predict.
An example of that is a video by Daniel Willingham that has gained some traction on YouTube that declares that learning styles is bunk. It is filled with lots of unsupported phrases like "that is not how the brain works" as if we had a really clear picture of how the brain works (never mind how we learn). The only thing that can be said definitively is that more research needs to be done. Another really big problem with the video is that it ignores any research that has been done and there is a lot of it out there. To say that there has not been any research that supports the idea of learning styles means that Willingham has not done a thorough review of the literature.
4. Comparing Student Learning Styles in an Online Distance Learning Class and an Equivalent On-Campus Class by David P. Diaz and Ryan B. Cartnal, Cuesta Community College
"More than 400 students from four universities in America and Britain completed measures of learning style preference, general knowledge (as a proxy for intelligence), and preference for examination method. Learning style was consistently associated with preferences..."