A family of Microsoft relational database management systems designed for ease of use.
Unfortunately this is yet another bug that has been around for a while (since Office XP at least) that Microsoft refuses to fix. Even though it alters the user's code, Microsoft doesn't consider it important enough to spend any time to try and correct. I would be very surprised if this bug isn't in Access 2013 - which I have and hate more than 2010.
You can go into Tools -> Options and uncheck the Auto Syntax Check to stop autocorrect from working altogether but then you'd lose all the functionality of it.
I try to remember not to use the parenthesis and check my code after I use a function in a multi-line line of code and watch my code when moving to a new line. Be careful - if you add code without adding another new line, the next line of code will be appended to the end of the last line with the _ .