title: Distinct α- and β-band rhythms over rat somatosensory cortex with similar properties as in humans.
abstract: We demonstrate distinct α- (7-14 Hz) and β-band (15-30 Hz) rhythms in rat somatosensory cortex in vivo using epidural electrocorticography recordings. Moreover, we show in rats that a genuine β-rhythm coexists alongside β-activity that reflects the second harmonic of the arch-shaped somatosensory α-rhythm. This demonstration of a genuine somatosensory β-rhythm depends on a novel quantification of neuronal oscillations that is based on their rhythmic nature: lagged coherence. Using lagged coherence, we provide two lines of evidence that this somatosensory β-rhythm is distinct from the second harmonic of the arch-shaped α-rhythm. The first is based on the rhythms' spatial properties: the α- and β-rhythms are demonstrated to have significantly different topographies. The second is based on the rhythms' temporal properties: the lagged phase-phase coupling between the α- and β-rhythms is demonstrated to be significantly less than would be expected if both reflected a single underlying nonsinusoidal rhythm. Finally, we demonstrate that 1) the lagged coherence spectrum is consistent between signals from rat and human somatosensory cortex; and 2) a tactile stimulus has the same effect on the somatosensory α- and β-rhythms in both rats and humans, namely suppressing them. Thus we not only provide evidence for the existence of genuine α- and β-rhythms in rat somatosensory cortex, but also for their homology to the primate sensorimotor α- and β-rhythms.
authors.affiliation: Radboud University, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands; and.
authors.forename: Anne M M
authors.identifier: 0000-0001-9769-6750
authors.initials: AM
authors.lastname: Fransen
authors.affiliation: Radboud University, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands; and.
authors.forename: George
authors.initials: G
authors.lastname: Dimitriadis
authors.affiliation: Radboud University, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands; and Oxford Centre for Human Brain Activity, Department of Psychiatry, University of Oxford, Oxford, United Kingdom.
authors.forename: Freek
authors.initials: F
authors.lastname: van Ede
authors.affiliation: Radboud University, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands; and e.maris@donders.ru.nl.
authors.forename: Eric
authors.identifier: 0000-0001-5166-1800
authors.initials: E
authors.lastname: Maris
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000513:Alpha Rhythm / Q000502:physiology*; D000818:Animals; D001611:Beta Rhythm / Q000502:physiology*; D001931:Brain Mapping; D000069280:Electrocorticography; D004566:Electrodes; D005260:Female; D005583:Fourier Analysis; D006801:Humans; D008297:Male; D010507:Periodicity; D010812:Physical Stimulation; D051381:Rats; D020318:Rats, Long-Evans; D013003:Somatosensory Cortex / Q000502:physiology*; D014110:Touch
keywords: barrel cortex; sensorimotor oscillations; somatosensory cortex; β-rhythm; μ-rhythm