Born in 1985 in Manhattan, Polachek spent her early years living in Tokyo, Japan with her family where she was exposed to traditional Japanese music. Around age six, she moved back to the States. Growing up in Greenwich, Connecticut, she rode horses, sang in the school choir, and began playing the keyboard. During high school, she discovered punk, emo, and indie rock, and played in several bands before heading to college.
It was in early 2006, while a student at the University of Colorado in Boulder, that Polachek formed Chairlift with Aaron Pfenning with the aim of providing music for haunted houses. After finding that their work transcended its original purpose, Pfenning and Polachek pulled up stakes and headed east, settling in Brooklyn before adding third member Patrick Wimberly. They quickly made a name for themselves, playing shows with similar up-and-comers like MGMT and Yeasayer while inking a contract with the independent label Kanine. Chairlift's first release on the label, a single titled "Evident Utensil," featured a remix by MGMT and was a precursor to the group's full-length debut. Issued in 2008, Does You Inspire You received an extra promotional boost when "Bruises" appeared in a commercial for a popular tech company. By early 2009, major labels came calling and Chairlift signed to Columbia, which reissued Does You Inspire You that April. Sophomore album Something was recorded by the duo of Polachek and Wimberly following the departure of Pfenning. Arriving in early 2012, it elevated the band's kaleidoscopic pop to a grander scale with assistance from producers Dan Carey and Alan Moulder. The album cracked the Billboard 200 and ended up on many "Best of 2012" lists. One fan of the record turned out to be Beyoncé, who invited the duo to help collaborate on songs for Beyoncé. Making it onto the final 2013 album was "No Angel," which Polachek co-wrote with Beyoncé and James Fauntleroy. Early the next year, Polachek made her solo debut with Arcadia (Terrible Records), releasing it under the moniker Ramona Lisa. She recorded the entire album on her laptop, using only MIDI instrumentation and no external microphones. The EP Dominic followed before the end of 2014, with the three-track Piano Versions arriving in 2015. The following year, she reunited with Wimberly for Chairlift's third album, Moth, which found the duo adopting a slicker, more pop-oriented sound. Featuring instrumental input from Quadron's Robin Hannibal, the record was issued on Columbia in early 2016. Polachek also contributed songwriting to a track from that year's Birds in the Trap Sing McKnight by rapper Travis Scott. In January 2017, she released her first instrumental album, Drawing the Target Around the Arrow, under her initials, CEP. An hour-long set built from sine waves, it arrived via Pannonica Records. Chairlift disbanded later in 2017, performing a set of farewell shows that April, with their final set taking place at Brooklyn Steel. By the end of 2017, Polachek had contributed writing to new releases by Beach Fossils, Charli XCX, Fischerspooner, Solange, and Pentatonix offshoot Superfruit. She appeared as a featured vocalist on 2018 recordings by Blood Orange, the Night Game, and Charli XCX. In 2019, she returned with the electro-pop track "Door," released on Columbia Records and using her own name. Several more songs appeared online, including "Ocean of Tears," Parachute," and "So Hot You're Hurting My Feelings," all of which led up to release of the full-length, Pang. The album found Polachek working with handful of collaborators, including Danny L. Harle, A.G. Cook, Andrew Wyatt, and others. ~ Marcy Donelson & Chris True, Rovi