TY - JOUR
T1 - Diversity of sharp-wave-ripple LFP signatures reveals differentiated brain-wide dynamical events
AU - Ramirez-Villegas, J F
AU - Logothetis, N K
AU - Besserve, M
N1 - Ramirez-Villegas, Juan F Logothetis, Nikos K Besserve, Michel eng 2015/11/06 06:00 Proc Natl Acad Sci U S A. 2015 Nov 17;112(46):E6379-87. doi: 10.1073/pnas.1518257112. Epub 2015 Nov 4.
PY - 2015
Y1 - 2015
N2 - Sharp-wave-ripple (SPW-R) complexes are believed to mediate memory reactivation, transfer, and consolidation. However, their underlying neuronal dynamics at multiple scales remains poorly understood. Using concurrent hippocampal local field potential (LFP) recordings and functional MRI (fMRI), we study local changes in neuronal activity during SPW-R episodes and their brain-wide correlates. Analysis of the temporal alignment between SPW and ripple components reveals well-differentiated SPW-R subtypes in the CA1 LFP. SPW-R-triggered fMRI maps show that ripples aligned to the positive peak of their SPWs have enhanced neocortical metabolic up-regulation. In contrast, ripples occurring at the trough of their SPWs relate to weaker neocortical up-regulation and absent subcortical down-regulation, indicating differentiated involvement of neuromodulatory pathways in the ripple phenomenon mediated by long-range interactions. To our knowledge, this study provides the first evidence for the existence of SPW-R subtypes with differentiated CA1 activity and metabolic correlates in related brain areas, possibly serving different memory functions.
AB - Sharp-wave-ripple (SPW-R) complexes are believed to mediate memory reactivation, transfer, and consolidation. However, their underlying neuronal dynamics at multiple scales remains poorly understood. Using concurrent hippocampal local field potential (LFP) recordings and functional MRI (fMRI), we study local changes in neuronal activity during SPW-R episodes and their brain-wide correlates. Analysis of the temporal alignment between SPW and ripple components reveals well-differentiated SPW-R subtypes in the CA1 LFP. SPW-R-triggered fMRI maps show that ripples aligned to the positive peak of their SPWs have enhanced neocortical metabolic up-regulation. In contrast, ripples occurring at the trough of their SPWs relate to weaker neocortical up-regulation and absent subcortical down-regulation, indicating differentiated involvement of neuromodulatory pathways in the ripple phenomenon mediated by long-range interactions. To our knowledge, this study provides the first evidence for the existence of SPW-R subtypes with differentiated CA1 activity and metabolic correlates in related brain areas, possibly serving different memory functions.
U2 - 10.1073/pnas.1518257112
DO - 10.1073/pnas.1518257112
M3 - Article
SN - 1091-6490
VL - 112
SP - E6379-87
JO - Proc Natl Acad Sci U S A
JF - Proc Natl Acad Sci U S A
IS - 46
ER -