If your brain is in a musically induced coma from all those high-carb holiday tunes, the Pacifica String Quartet has the aural antidote. Its concert on Sunday, Jan. 12, at 3 p.m., St. Francis Auditorium, features nourishing works by Beethoven, Shostakovich, and Shulamit Ran. An open rehearsal takes place at 10 a.m., no charge.