Sequential structure of neocortical spontaneous activity in vivo

• DOI: 10.1073/pnas.0605643104
• Publication Date: 2006-12-22T01:40:13Z
• Authors: Artur Luczak; Peter Barthó; Stephan L. Marguet; György Buzsáki; Kenneth D. Harris
• Keywords: Neocortex; Nerve net; Sensory stimulation therapy; Local field potential; Biological neural network

Even in the absence of sensory stimulation, neocortex shows complex spontaneous activity patterns, often consisting alternating "DOWN" states generalized neural silence and "UP" massive, persistent network activity. To investigate how this propagates through neuronal assemblies vivo, we simultaneously recorded populations 50-200 cortical neurons layer V anesthetized awake rats. Each neuron displayed a virtually unique spike pattern during UP states, with diversity seen amongst both putative pyramidal cells interneurons, reflecting but stereotypically organized sequential spread activation local networks. Spike timing was most precise first approximately 100 ms after state onset, decayed as progressed. A subset propagated traveling waves, waves passing given point either direction initiated similar sequences, suggesting networks substrate firing patterns. search for repeating motifs indicated that their occurrence structure predictable from neurons' individual latencies to onset. We suggest these stereotyped patterns arise interplay intrinsic cellular conductances circuit properties.