 The episode features mash @-@ up covers of " It 's My Life " by Bon Jovi and " Confessions Part II " by Usher , and " Halo " by Beyoncé Knowles and " Walking on Sunshine " by Katrina and the Waves . Both tracks were released as singles , available for digital download . " It 's My Life / Confessions Part II " charted at number 7 in Ireland , 14 in the UK , 22 in Australia , 25 in Canada and 30 in America , while " Halo / Walking on Sunshine " charted at number 4 in Ireland , 9 in the UK , 10 in Australia , 28 in Canada and 40 in America . Michele has revealed that she practiced talking " <unk> " for several days in order to convey the effects of pseudoephedrine on Rachel . In order to portray the character in her altered state , she questioned : " How manic is the right amount of manic ? What would Rachel be like on <unk> ? What would she sound like ? " She deemed performing the mash @-@ up piece in that state " so much fun " . 
