Letter

Pitch perception is critical for identifying and segregating auditory objects¹, especially in the context of music and speech. The perception of pitch is not unique to humans and has been experimentally demonstrated in several animal species^{2, 3}. Pitch is the subjective attribute of a sound's fundamental frequency (f₀) that is determined by both the temporal regularity and average repetition rate of its acoustic waveform. Spectrally dissimilar sounds can have the same pitch if they share a common f₀. Even when the acoustic energy at f₀ is removed ('missing fundamental') the same pitch is still perceived¹. Despite its importance for hearing, how pitch is represented in the cerebral cortex is unknown. Here we show the existence of neurons in the auditory cortex of marmoset monkeys that respond to both pure tones and missing fundamental harmonic complex sounds with the same f₀, providing a neural correlate for pitch constancy¹. These pitch-selective neurons are located in a restricted low-frequency cortical region near the anterolateral border of the primary auditory cortex, and is consistent with the location of a pitch-selective area identified in recent imaging studies in humans^{4, 5}.

1. Laboratory of Auditory Neurophysiology, Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland 21025, USA

Correspondence to: Daniel Bendor¹Xiaoqin Wang¹ Correspondence and requests for materials should be addressed to D.B. (Email: dbendor@bme.jhu.edu) or X.W. (Email: xwang@bme.jhu.edu).

Received 12 January 2005; Accepted 26 May 2005