title: Auditory ERPs to stimulus deviance in an awake chimpanzee (Pan troglodytes): towards hominid cognitive neurosciences.
abstract: BACKGROUND
  For decades, the chimpanzee, phylogenetically closest to humans, has been analyzed intensively in comparative cognitive studies. Other than the accumulation of behavioral data, the neural basis for cognitive processing in the chimpanzee remains to be clarified. To increase our knowledge on the evolutionary and neural basis of human cognition, comparative neurophysiological studies exploring endogenous neural activities in the awake state are needed. However, to date, such studies have rarely been reported in non-human hominid species, due to the practical difficulties in conducting non-invasive measurements on awake individuals.
  
  
  RESULTS
  We measured auditory event-related potentials (ERPs) of a fully awake chimpanzee, with reference to a well-documented component of human studies, namely mismatch negativity (MMN). In response to infrequent, deviant tones that were delivered in a uniform sound stream, a comparable ERP component could be detected as negative deflections in early latencies.
  
  
  CONCLUSIONS
  The present study reports the MMN-like component in a chimpanzee for the first time. In human studies, various ERP components, including MMN, are well-documented indicators of cognitive and neural processing. The results of the present study validate the use of non-invasive ERP measurements for studies on cognitive and neural processing in chimpanzees, and open the way for future studies comparing endogenous neural activities between humans and chimpanzees. This signifies an essential step in hominid cognitive neurosciences.
authors.affiliation: The University of Tokyo, Tokyo, Japan. aueno@ecs.c.u-tokyo.ac.jp
authors.forename: Ari
authors.initials: A
authors.lastname: Ueno
authors.forename: Satoshi
authors.initials: S
authors.lastname: Hirata
authors.forename: Kohki
authors.initials: K
authors.lastname: Fuwa
authors.forename: Keiko
authors.initials: K
authors.lastname: Sugama
authors.forename: Kiyo
authors.initials: K
authors.lastname: Kusunoki
authors.forename: Goh
authors.initials: G
authors.lastname: Matsuda
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Fukushima
authors.forename: Kazuo
authors.initials: K
authors.lastname: Hiraki
authors.forename: Masaki
authors.initials: M
authors.lastname: Tomonaga
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Hasegawa
mesh_terms: D000818:Animals; D003071:Cognition; D005072:Evoked Potentials, Auditory; D005260:Female; D002679:Pan troglodytes / Q000502:physiology*