title: Non-invasive primate head restraint using thermoplastic masks.
abstract: BACKGROUND
  The success of many neuroscientific studies depends upon adequate head fixation of awake, behaving animals. Typically, this is achieved by surgically affixing a head-restraint prosthesis to the skull.
  
  
  METHODS
  Here we report the use of thermoplastic masks to non-invasively restrain monkeys' heads. Mesh thermoplastic sheets become pliable when heated and can then be molded to an individual monkey's head. After cooling, the custom mask retains this shape indefinitely for day-to-day use.
  
  
  RESULTS
  We successfully trained rhesus macaques (Macaca mulatta) to perform cognitive tasks while wearing thermoplastic masks. Using these masks, we achieved a level of head stability sufficient for high-resolution eye-tracking and intracranial electrophysiology.
  
  
  CONCLUSIONS
  Compared with traditional head-posts, we find that thermoplastic masks perform at least as well during infrared eye-tracking and single-neuron recordings, allow for clearer magnetic resonance image acquisition, enable freer placement of a transcranial magnetic stimulation coil, and impose lower financial and time costs on the lab.
  
  
  CONCLUSIONS
  We conclude that thermoplastic masks are a viable non-invasive form of primate head restraint that enable a wide range of neuroscientific experiments.
authors.affiliation: Department of Neurobiology and Center for Cognitive Neuroscience, Levine Science Research Center, Box 90999, Duke University, Durham, NC 27708, USA. Electronic address: caroline.drucker@duke.edu.
authors.forename: Caroline B
authors.initials: CB
authors.lastname: Drucker
authors.affiliation: Department of Neurobiology and Center for Cognitive Neuroscience, Levine Science Research Center, Box 90999, Duke University, Durham, NC 27708, USA. Electronic address: monica.carlson@duke.edu.
authors.forename: Monica L
authors.initials: ML
authors.lastname: Carlson
authors.affiliation: Department of Neurobiology and Center for Cognitive Neuroscience, Levine Science Research Center, Box 90999, Duke University, Durham, NC 27708, USA; Japan Society for the Promotion of Science, Kojimachi Business Center Building, 5-3-1 Kojimachi, Chiyoda-ku 102-0083, Tokyo, Japan. Electronic address: kt131@duke.edu.
authors.forename: Koji
authors.initials: K
authors.lastname: Toda
authors.affiliation: Department of Neurobiology and Center for Cognitive Neuroscience, Levine Science Research Center, Box 90999, Duke University, Durham, NC 27708, USA. Electronic address: nicholas.dewind@duke.edu.
authors.forename: Nicholas K
authors.initials: NK
authors.lastname: DeWind
authors.affiliation: Department of Neurobiology and Center for Cognitive Neuroscience, Levine Science Research Center, Box 90999, Duke University, Durham, NC 27708, USA; Department of Evolutionary Anthropology, 104 Biological Sciences Building, Box 90383, Duke University, Durham, NC 27708, USA; Duke Institute for Brain Sciences, Levine Science Research Center, Box 90999, Duke University, Durham, NC 27708, USA. Electronic address: platt@neuro.duke.edu.
authors.forename: Michael L
authors.initials: ML
authors.lastname: Platt
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001921:Brain / Q000166:cytology; D004867:Equipment Design; D005133:Eye Movements / Q000502:physiology*; D005260:Female; D006257:Head / Q000502:physiology*; D008253:Macaca mulatta; D008279:Magnetic Resonance Imaging; D008297:Male; D008397:Masks; D009474:Neurons / Q000502:physiology; D012149:Restraint, Physical; D050781:Transcranial Magnetic Stimulation; D014851:Wakefulness
keywords: Electrophysiology; Eye-tracking; Head restraint; Head-post; Non-human primates; Transcranial magnetic stimulation