• 
  Daniel Barenboim

  Himself
• 
  Tony Cicoria

  Himself
• 
  Evelyn Glennie

  Herself
• 
  Bobby McFerrin

  Himself
• 
  Oliver Sacks

  Himself
• 
  Richard Hawley

  Himself
• 
  Brian Greene

  Himself
• 
  Daniel Levitin

  Himself (as Dr. Daniel Levitin)

• 
  Richard Hawley

  Himself

• 
  Dewald Aukema

  imagine
• 
  Yo-Yo Ma

  Himself
• 
  Audra McDonald

  Narator
• 
  Jarvis Cocker

  Himself