ABSTRACT Odor stimulation evokes complex spatiotemporal activity in the olfactory bulb, suggesting that both the identity of activated neurons and the timing of their activity convey

information about odors. However, whether and how downstream neurons decipher these temporal patterns remains unknown. We addressed this question by measuring the spiking activity of

downstream neurons while optogenetically stimulating two foci in the olfactory bulb with varying relative timing in mice. We found that the overall spike rates of piriform cortex neurons

(PCNs) were sensitive to the relative timing of activation. Posterior PCNs showed higher sensitivity to relative input times than neurons in the anterior piriform cortex. In contrast,

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Log in * Learn about institutional subscriptions * Read our FAQs * Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS THE CIRCADIAN CLOCK IN THE PIRIFORM CORTEX INTRINSICALLY

TUNES DAILY CHANGES OF ODOR-EVOKED NEURAL ACTIVITY Article Open access 27 March 2023 LONG-RANGE GABAERGIC PROJECTIONS CONTRIBUTE TO CORTICAL FEEDBACK CONTROL OF SENSORY PROCESSING Article

Open access 12 November 2022 FAST UPDATING FEEDBACK FROM PIRIFORM CORTEX TO THE OLFACTORY BULB RELAYS MULTIMODAL IDENTITY AND REWARD CONTINGENCY SIGNALS DURING RULE-REVERSAL Article Open

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optical control of neural activity. _Nat. Neurosci._ 8, 1263–1268 (2005). Article  CAS  PubMed  Google Scholar  Download references ACKNOWLEDGEMENTS We thank C. Dulac (Harvard University)

for sharing resources generously, comments on the manuscript and providing _Tbet-cre; ChR2__loxP/loxP_ mice (generated by A.L.). We thank E. Soucy and T. Sato for technical support and D.F.

Albeanu and A.K. Dhawale for technical advice. We thank Y. Ben-Shaul, C. Poo, N. Eshel and J.Y. Cohen for their comments on the manuscript. This work was supported by Human Frontier Science

Program (R.H.), a Howard Hughes Medical Institute Collaborative Innovation Award, a Smith Family New Investigator Award, the Alfred Sloan Foundation and the Milton Fund (N.U.), and a grant

from the US National Institutes of Health (V.N.M.). AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department of Molecular and Cellular Biology, Center for Brain Science, Harvard University,

Cambridge, Massachusetts, USA Rafi Haddad, Anne Lanjuin, Venkatesh N Murthy & Naoshige Uchida * Allen Institute for Brain Science, Seattle, Washington, USA Linda Madisen & Hongkui

Zeng Authors * Rafi Haddad View author publications You can also search for this author inPubMed Google Scholar * Anne Lanjuin View author publications You can also search for this author

inPubMed Google Scholar * Linda Madisen View author publications You can also search for this author inPubMed Google Scholar * Hongkui Zeng View author publications You can also search for

this author inPubMed Google Scholar * Venkatesh N Murthy View author publications You can also search for this author inPubMed Google Scholar * Naoshige Uchida View author publications You

can also search for this author inPubMed Google Scholar CONTRIBUTIONS R.H. and N.U. conceived the experiment. R.H. performed the experiment. A.L. generated and characterized the _Tbet-cre;

ChR2__loxP/loxP_ mice, and L.M. and H.Z. generated and characterized the _ChR2__loxP/loxP_ mice. V.N.M. provided the _Omp-ChR2_ mice. R.H. and N.U. wrote the paper and A.L., V.N.M. and H.Z.

provided feedback on the manuscript. CORRESPONDING AUTHOR Correspondence to Naoshige Uchida. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing financial interests.

SUPPLEMENTARY INFORMATION SUPPLEMENTARY TEXT AND FIGURES Supplementary Figures 1–10 (PDF 5930 kb) RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Haddad,

R., Lanjuin, A., Madisen, L. _et al._ Olfactory cortical neurons read out a relative time code in the olfactory bulb. _Nat Neurosci_ 16, 949–957 (2013). https://doi.org/10.1038/nn.3407

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