This post I'll be looking at a paper entitled "Training the Motor Cortex by Observing the Actions of Others During Immobilization" by Fadiga, et al. published in Cerebral Cortex in July, 2013. If you can get access to the article, I highly recommend it- it is a fairly short, but interesting read. If not, I'll do my best to make this post understandable without reading the paper.
The background science:
Our brains are "plastic" which means that they are always making (and breaking!) connections between neurons. Repetitive action strengthens these connections, whereas disuse weakens them. Think about sledding: every time you go down a hill and take the same path as before, it becomes more entrenched. This is the same (although grossly simplified way) your brain works. The stronger the neural path, the easier and more automatic the action becomes. This means that you want the neural path for something like a heel turn to be pretty well entrenched, because you have a lot of other things to think about (smile!) when you are competing. One way (probably the best way) to do this, is through lots of (perfect) practice. However, there are some times when we can't always practice. I was on DanceForums earlier this year when one of the members brought up the question about what to do when you are injured. Fadiga, et al. suggest that action observation might be a good thing to try. (Side note- if you haven't been to DanceForums.com and you are a ballroom dancer, you need to go there immediately after reading this post. It is an amazing resource).
The authors wanted to compare two forms of mental practice and their effectiveness at preventing the shriveling/ building up these neural paths. The first method is motor imagery (MI). Motor imagery basically means thinking about yourself doing the task, and about all the associated feelings. The second is action observation (AO) which involves watching a first person perspective video of the given task (in the paper, they used reaching for an object).
First, the subjects underwent transcranial magnetic stimulation (TMS- a big magnet used to look at neural activity) to look at the activity in the brain area involved in arm reaching. The researchers then immobilized the subjects' arms for 10 hours. After the 10 hours were up, the subjects were assigned to one of three groups- a group that just watched nature documentaries (control group), action observation group where they watched a first person video of an arm reaching for an object, and a motor imagery where the subjects imagined themselves reaching for an object. The researchers then did another TMS to measure how much the neural paths for arm reaching had been depressed through immobilization.
The investigators found that the action observation group had the least amount of cortical activity depression, followed by motor imagery and then the nature-video control.This means that action observation was the most effective way to keep the skill of arm reaching up while the arm was immobilized.
So what does this all mean, anyways?
Action observation may have potential as a supplementary training method for ballroom dancers. It has shown potential to help prevent loss of skills when practice isn't an option. It is certainly worth a try (it can't hurt, in any case!) However, it is important to note the conditions in which this experiment was conducted. They used a very simple task (reaching for an objects). In case you haven't noticed, most actions in ballroom are much more complex than reaching for an object! Secondly, the researchers used first person videos for the action observation videos. These would be extremely disorienting to watch, in my opinion (especially when the follow is all projected up and left and looking at the ceiling the whole time!) Perhaps someone can try this with one of those little cameras you attach to your head? If you do- send me the result- I'm very curious :) This first person perspective may also provide limited information on the aspect the observer is interested in. My visual perspective as a follow doesn't often include what my feet are doing during a heel turn. Maybe if it was a video of a single step (for example, a heel turn) shot from a first person perspective including the necessary information (e.g. I would wear a camera on my head and look at my feet while performing a heel turn). In any case, this paper certainly provides an interesting starting point for future research to investigate. Maybe someone will even do a study about action observations in dancers...if only I was doing a thesis... (actually, I'm still really glad I'm not doing a thesis....)
Go watch some videos! In all perspectives, but especially first person (if you can find them). They may help, or not, but they certainly won't hurt. Off to youtube for me it is...