"Is there a simple way to name outputs as an existing variable & what the output is"
Nope. There is a complex, slow, and buggy way (that some beginners love, for some reason).
"... it would be useful to first create a variable TrialName = trial1 and then ... do the same thing for trial 2 and so on."
You might think that that would be "useful", but in reality it will just make your code complex, slow, buggy, and hard to debug. It will be a waste of your time, and a total waste of MATLAB.
You would be much better off learning how to use indexing. Indexing is neat, simple, efficient, and easy to debug. Indexing lets you use MATLAB efficiently because it lets you keep your data together as much as possible (which is good rule of thumb).
Read this to know more about why you should avoid magically creating or accessing variable names like that:
If you have any questions that have not already been discussed in the thousand other threads where this topic has been exhaustively discussed, or that are not already covered in the MATLAB documentation (which states "A frequent use of the eval function is to create sets of variables such as A1, A2, ..., An, but this approach does not use the array processing power of MATLAB and is not recommended. The preferred method is to store related data in a single array"), then please ask.
