In my opinion, a slump usually means you have lost confidence and doubt in your game. It may have nothing to do with your physical game, therefore more practice will not necessarily fix the problem, and have more to do with the fact that you are not scoring well or scoring under average or whatever and you are mentally allowing this to affect your game. Regardless, a mental slump can affect your physical game, especially if you find yourself tweaking your shot or forcing shots or whatever in hopes of scoring better. A few pieces of advice that have worked for me to overcome mental slumps so that my physical game is not affected:
1) If I am having a bad night, I turn off the score in my head. Seriously, I do not pay attention to my score on the monitor and instead focus solely on my physical shot and delivery. I want to execute the shot the way I know how to execute and do not want to put the pressure that I need to strike, or double or whatever to affect me mentally. I might go through a few bad frames while I work through a problem, but usually I will find confidence in my shot again and will no longer have self doubt by not worrying about the score and concentrating more on the physical delivery and shot instead.
2) If I am having a few bad nights or week or two or whatever, I walk away from bowling for a week or two. When it isn't fun and I walk away from the center ticked off because I didn't score well, or haven't been scoring well, I find it better to just walk away for a week and gain fresh perspective. Usually, by this point, I am so mentally frustrated with the lack of confidence in my game that it isn't fun anymore and I find a shot little break does wonders for me mentally. When I return, I always have lower expectations, therefore no need to worry about the score, and can focus on the physical aspects of my game to regain confidence.
I think the big thing you will notice with my advice is it is important to regain the confidence in your physical game and remove any self-doubt. Whatever works for you is what you should do whether that is more practice, seeking a coach, posting a video or whatever, but make certain you focus on regaining confidence in your physical game and removing any self doubt you have as a result of the slump and you will be fine.