Adaptive behavior depends on an animal’s ability to ignore uninformative stimuli, such as repeated presentations of the same stimulus, and, instead, detect informative, novel stimuli in its environment. The primate prefrontal cortex (PFC) is known to play a central role in this ability. However, the neural mechanisms underlying the ability to differentiate between repeated and novel stimuli are not clear. We hypothesized that the coupling between different frequency bands of the local field potential (LFP) underlies the PFC’s role in differentiating between repeated and novel stimuli. Specifically, we hypothesized that whereas the presentation of a novel-stimulus induces strong cross-frequency coupling, repeated presentations of the same stimulus attenuates this coupling. To test this hypothesis, we recorded LFPs from the ventrolateral PFC (vPFC) of rhesus monkeys while they listened to a novel vocalization and repeated presentations of the same vocalization. We found that the cross-frequency coupling between the gamma-band amplitude and theta-band phase of the LFP was modulated by repeated presentations of a stimulus. During the first (novel) presentation of a stimulus, gamma-band activity was modulated by the theta-band phase. However, with repeated presentations of the same stimulus, this cross-frequency coupling was attenuated. These results suggest that cross-frequency coupling may play a role in the neural computations that underlie the differentiation between novel and repeated stimuli in the vPFC.
Keywords: vocalization, rhesus monkey, neural oscillation, theta band, gamma band
Citation: Tsunada J, Baker AE, Christison-Lagay KL, Davis SJ and Cohen YE (2011) Modulation of cross-frequency coupling by novel and repeated stimuli in the primate ventrolateral prefrontal cortex. Front. Psychology 2:217. doi: 10.3389/fpsyg.2011.00217
Received: 11 June 2011;
Accepted: 18 August 2011;
Published online: 07 September 2011.
Edited by:Pascal Belin, University of Glasgow, UK
Reviewed by:Kristina Simonyan, Mount Sinai School of Medicine, USA
Copyright: © 2011 Tsunada, Baker, Christison-Lagay, Davis and Cohen. This is an open-access article subject to a non-exclusive license between the authors and Frontiers Media SA, which permits use, distribution and reproduction in other forums, provided the original authors and source are credited and other Frontiers conditions are complied with.
*Correspondence: Joji Tsunada, Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania School of Medicine, 3400 Spruce – 5 Ravdin, Philadelphia, PA 19104, USA. e-mail: email@example.com