Download CNS member No: S423400046A Precise spatiotemporal patterns of

CNS member No: S423400046A
Precise spatiotemporal patterns of neuronal network
activation during persistent reverberatory activity
Lei QI‡, Peng-Cheng ZHOU‡, Pak-Ming LAU, Guo-Qiang BI
*
Hefei National Laboratory for Physical Sciences at the Microscale, and School of
Life Science, University of Science and Technology of China, Hefei 230027, China
‡ These authors contributed equally to this work.
* Corresponding author
Email: [email protected]
Abstract: In Hebb’s theory of the cell assembly, short-term memory traces can be
stored in closed loop neuronal circuits in form of persistent reverberatory activity.
In previous studies, we have observed persistent network reverberation in cultured
hippocampal neurons (Lau and Bi, PNAS, 2005). Here, we investigated the
spatiotemporal dynamics of such collective activity of neurons grown on
multi-electrode arrays (MEAs). In this preparation, a reverberation episode
consisted of many distinct population bursts defined as reverberation event, each
involved the spiking activity of many neurons within a time span of tens of
milliseconds. Here, we developed a robust method to define the similarity between
two events and use it to find conserved patterns among all events. We found that
there existed conserved spatiotemporal patterns with high temporal precision in
cultured neuronal networks. Furthermore, multiple patterns could co-exist in the
same network during spontaneous reverberation and could occur intermittently within
the same reverberation episode. In smaller networks, reverberation could only be
evoked by stimulating an input channel, and sometimes only one conserved pattern
was identified. These results suggested that precise spatiotemporal dynamics in
neural circuits might allow for more efficient information coding in the brain.
Keywords: Neural network, Cell assembly, multielectrode array, reverberation