Name
Title | ||
|---|---|---|
Comparison of glomerular activity patterns by fMRI and wide-field calcium imaging: Implications for principles underlying odor mapping. |
Abstract | ||
|---|---|---|
Functional imaging signals arise from distinct metabolic and hemodynamic events at the neuropil, but how these processes are influenced by pre- and post-synaptic activities need to be understood for quantitative interpretation of stimulus-evoked mapping data. The olfactory bulb (OB) glomeruli, spherical neuropil regions with well-defined neuronal circuitry, can provide insights into this issue. Optical calcium-sensitive fluorescent dye imaging (OICa2+) reflects dynamics of pre-synaptic input to glomeruli, whereas high-resolution functional magnetic resonance imaging (fMRI) using deoxyhemoglobin contrast reveals neuropil function within the glomerular layer where both pre- and post-synaptic activities contribute. We imaged odor-specific activity patterns of the dorsal OB in the same anesthetized rats with fMRI and OICa2+ and then co-registered the respective maps to compare patterns in the same space. Maps by each modality were very reproducible as trial-to-trial patterns for a given odor, overlapping by ~80%. Maps evoked by ethyl butyrate and methyl valerate for a given modality overlapped by ~80%, suggesting activation of similar dorsal glomerular networks by these odors. Comparison of maps generated by both methods for a given odor showed ~70% overlap, indicating similar odor-specific maps by each method. These results suggest that odor-specific glomerular patterns by high-resolution fMRI primarily tracks pre-synaptic input to the OB. Thus combining OICa2+ and fMRI lays the framework for studies of OB processing over a range of spatiotemporal scales, where OICa2+ can feature the fast dynamics of dorsal glomerular clusters and fMRI can map the entire glomerular sheet in the OB. |
Year | DOI | Venue |
|---|---|---|
2016 | 10.1016/j.neuroimage.2015.11.048 | NeuroImage |
Keywords | Field | DocType |
BOLD signal,Intrinsic signal,Functional hyperemia,Glutamate,Energetics,Olfaction | Brain mapping,Olfactory bulb,Olfaction,Neuroscience,Functional magnetic resonance imaging,Computer science,Odor,Functional imaging,Calcium imaging,Neuropil | Journal |
Volume | ISSN | Citations |
126 | 1053-8119 | 2 |
PageRank | References | Authors |
0.38 | 6 | 7 |
Name | Order | Citations | PageRank |
|---|---|---|---|
| Basavaraju G. Sanganahalli | 1 | 13 | 3.66 |
| Michelle R Rebello | 2 | 2 | 0.38 |
| Peter Herman | 3 | 3 | 1.07 |
| Xenophon Papademetris | 4 | 88 | 6.28 |
| Gordon M Shepherd | 5 | 2 | 0.38 |
| Justus V Verhagen | 6 | 2 | 0.38 |
| Fahmeed Hyder | 7 | 23 | 3.56 |