| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
* To whom correspondence should be addressed. E-mail: wuj{at}georgetown.edu.
Neocortical "theta" oscillation (5- 12 Hz) has been observed in animals and human subjects but little is known about how the oscillation is organized in the neocortical intrinsic networks. Here we use voltage-sensitive dye and optical imaging to study a carbachol / bicuculline induced theta (
8Hz) oscillation in rat neocortical slices. The imaging has large signal-to-noise ratio, allowing us to map the phase distribution over the tissue during the oscillation. The oscillation was organized as spontaneous epochs and each epoch was composed of a "first spike", a "regular" period (with relatively stable frequency and amplitude) and an "irregular" period (with variable frequency and amplitude) of oscillations. During each cycle of the regular oscillation one wave of activation propagated horizontally (parallel to the cortical lamina) across the cortical section at a velocity of 50 mm/sec. Vertically the activity was synchronized through all cortical layers. This pattern of one propagating wave associated with one oscillation cycle was seen during all the regular cycles. The oscillation frequency varied noticeably at two neighboring horizontal locations (330 µm apart), suggesting that the oscillation is locally organized and each local oscillator is about equal or less than 300 um wide horizontally. During irregular oscillations the spatiotemporal patterns were complex and sometimes the vertical synchronization decomposed, suggesting a de-coupling among local oscillators. Our data suggested that neocortical theta oscillation is sustained by multiple local oscillators. The coupling regime among the oscillators may determine the spatiotemporal pattern and switching between propagating waves and irregular patterns.
This article has been cited by other articles:
|
|
 |
|
  E. M. Izhikevich and G. M. Edelman Large-scale model of mammalian thalamocortical systems PNAS, March 4, 2008; 105(9): 3593 - 3598. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. J. Trevelyan, T. Baldeweg, W. van Drongelen, R. Yuste, and M. Whittington The Source of Afterdischarge Activity in Neocortical Tonic Clonic Epilepsy J. Neurosci., December 5, 2007; 27(49): 13513 - 13519. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. T. Lippert, K. Takagaki, W. Xu, X. Huang, and J.-Y. Wu Methods for Voltage-Sensitive Dye Imaging of Rat Cortical Activity With High Signal-to-Noise Ratio J Neurophysiol, July 1, 2007; 98(1): 502 - 512. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Bai, X. Huang, Q. Yang, and J.-Y. Wu Spatiotemporal Patterns of an Evoked Network Oscillation in Neocortical Slices: Coupled Local Oscillators J Neurophysiol, November 1, 2006; 96(5): 2528 - 2538. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Bandyopadhyay, B. Sutor, and J. J. Hablitz Endogenous Acetylcholine Enhances Synchronized Interneuron Activity in Rat Neocortex J Neurophysiol, March 1, 2006; 95(3): 1908 - 1916. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Raghavachari, J. E. Lisman, M. Tully, J. R. Madsen, E. B. Bromfield, and M. J. Kahana Theta Oscillations in Human Cortex During a Working-Memory Task: Evidence for Local Generators J Neurophysiol, March 1, 2006; 95(3): 1630 - 1638. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Bolea, J. V. Sanchez-Andres, X. Huang, and J.-y. Wu Initiation and Propagation of Neuronal Coactivation in the Developing Hippocampus J Neurophysiol, January 1, 2006; 95(1): 552 - 561. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
X. Huang, W. C. Troy, Q. Yang, H. Ma, C. R. Laing, S. J. Schiff, and J.-Y. Wu Spiral Waves in Disinhibited Mammalian Neocortex J. Neurosci., November 3, 2004; 24(44): 9897 - 9902. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
