Formation and reverberation of sequential neural activity patterns evoked by sensory stimulation are enhanced during cortical desynchronization.
Memory formation is hypothesized to involve the generation of event-specific neural activity patterns during learning and the subsequent spontaneous reactivation of these patterns. Here, we present evidence that these processes can also be observed in urethane-anesthetized rats and are enhanced by desynchronized brain state evoked by tail pinch, subcortical carbachol infusion, or systemic amphetamine administration. During desynchronization, we found that repeated tactile or auditory stimulation evoked unique sequential patterns of neural firing in somatosensory and auditory cortex and that these patterns then reoccurred during subsequent spontaneous activity, similar to what we have observed in awake animals. Furthermore, the formation of these patterns was blocked by an NMDA receptor antagonist, suggesting that the phenomenon depends on synaptic plasticity. These results suggest that anesthetized animals with a desynchronized brain state could serve as a convenient model for studying stimulus-induced plasticity to improve our understanding of memory formation and replay in the brain.
Department of Neuroscience, Canadian Centre for Behavioural Neuroscience, University of Lethbridge, 4401 University Drive, Lethbridge, AB T1K 3M4, Canada.
Edgar J
EJ
Bermudez Contreras
Andrea Gomez Palacio
AG
Schjetnan
Arif
A
Muhammad
Peter
P
Bartho
Bruce L
BL
McNaughton
Bryan
B
Kolb
Aaron J
AJ
Gruber
Artur
A
Luczak
D000161:Acoustic Stimulation; D000200:Action Potentials / Q000187:drug effects / Q000502:physiology*; D000596:Amino Acids / Q000378:metabolism; D000777:Anesthetics / Q000494:pharmacology; D000818:Animals; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000166:cytology* / Q000502:physiology*; D003344:Cortical Synchronization / Q000502:physiology*; D004569:Electroencephalography; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D020318:Rats, Long-Evans; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology; D013223:Statistics as Topic; D014110:Touch; D014520:Urethane / Q000494:pharmacology
D000596:Amino Acids; D000777:Anesthetics; C098463:dolaisoleucine; D014520:Urethane