For a time I supported adults with severe learning disabilities. Some staff swore they acted out more around the time of the full moon but I never observed a connection myself. I have had times when I've been more emotionally roused at the full moon but also times when I haven't been. While emotions can affect my speech, I don't think the full moon does. I wonder, though, if any female stutterers here have observed a correlation between their menstrual cycle and speech.