Answer the following question: Information: - The circulatory system, also called the cardiovascular system or the vascular system, is an organ system that permits blood to circulate and transport nutrients (such as amino acids and electrolytes), oxygen, carbon dioxide, hormones, and blood cells to and from the cells in the body to provide nourishment and help in fighting diseases, stabilize temperature and pH, and maintain homeostasis. The study of the blood flow is called hemodynamics. The study of the properties of the blood flow is called hemorheology. - William '' Will '' Cullen Hart ( born June 14 , 1971 ) is an American pop musician and painter . He was a co-founder of The Elephant 6 Recording Company , as well as the rock band The Olivia Tremor Control . Following that band 's breakup , Hart and several other former members regrouped to create Circulatory System . Hart grew up in Ruston , Louisiana , with Bill Doss , Jeff Mangum and Robert Schneider . Doss and Hart ( and , early on , Mangum ) combined their musical efforts in The Olivia Tremor Control . Hart and Doss blended their differing musical inclinations for the band : Hart being known as the sonic experimenter , Doss the proponent of pop. This difference is evidently clear in the music produced by each since the end of the Olivia Tremor Control . Hart 's Circulatory System maintains an interest in experimentation , while Doss ' Sunshine Fix focused on more traditionally structured Beatlesque pop. Will Cullen Hart is also a visual artist . He has created most , if not all of the artwork for the Olivia Tremor Control and Circulatory System ( among other Elephant 6 bands ) , as well as individual pieces . In a 2008 online interview with John Fernandes , it was revealed that Hart has been diagnosed with multiple sclerosis . - Music is an art form and cultural activity whose medium is sound and silence, which exist in time. The common elements of music are pitch (which governs melody and harmony), rhythm (and its associated concepts tempo, meter, and articulation), dynamics (loudness and softness), and the sonic qualities of timbre and texture (which are sometimes termed the "color" of a musical sound). Different styles or types of music may emphasize, de-emphasize or omit some of these elements. Music is performed with a vast range of instruments and vocal techniques ranging from singing to rapping; there are solely instrumental pieces, solely vocal pieces (such as songs without instrumental accompaniment) and pieces that combine singing and instruments. The word derives from Greek ("mousike"; "art of the Muses"). In its most general form, the activities describing music as an art form include the production of works of music (songs, tunes, symphonies, and so on), the criticism of music, the study of the history of music, and the aesthetic examination of music. Ancient Greek and Indian philosophers defined music as tones ordered horizontally as melodies and vertically as harmonies. Common sayings such as "the harmony of the spheres" and "it is music to my ears" point to the notion that music is often ordered and pleasant to listen to. However, 20th-century composer John Cage thought that any sound can be music, saying, for example, "There is no noise, only sound." - The Elephant 6 Recording Company (or simply Elephant 6) is a collective of American musicians who spawned many notable independent bands of the 1990s, including the Apples in Stereo, the Olivia Tremor Control, Neutral Milk Hotel, Beulah, Elf Power, of Montreal, The Minders, and Circulatory System. They are marked by a shared admiration of 1960s pop music. - The Minders is a band closely associated with The Elephant Six Collective. Started by Martyn Leaper in Denver, Colorado in 1996, the band's original members included Leaper on guitars and vocals, Rebecca Cole, on drums, Jeff Almond on guitar, and Marc Willhite on bass. - The Olivia Tremor Control is a psychedelic rock band that was prominent in the mid-to-late 1990s. It was, along with The Apples in Stereo and Neutral Milk Hotel, one of the three original projects of The Elephant 6 Recording Company. The band was founded by the remnants of the group Synthetic Flying Machine (Jeff Mangum, Bill Doss, and Will Cullen Hart) in 1994. The band went on hiatus in early 2000, and later reformed in 2009. - The Apples in Stereo, styled as The Apples in stereo, are an American rock band associated with Elephant Six Collective, a group of bands also including Neutral Milk Hotel and The Olivia Tremor Control. The band is largely a product of lead vocalist/guitarist/producer Robert Schneider, who writes the majority of the band's music and lyrics. Currently, The Apples in Stereo also includes longstanding members John Hill (rhythm guitar) and Eric Allen (bass), as well as more recent members John Dufilho (drums), John Ferguson (keyboards), and Ben Phelan (keyboards/guitar/trumpet). Given the paragraphs above, decide what entity has the relation 'instrument' with 'guitar'.
Answer:
will cullen hart