QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

The Journal of Neuroscience, August 19, 2009, 29(33):10191-10202; doi:10.1523/JNEUROSCI.1874-09.2009

This Article Full Text Full Text (PDF) Supplemental Data Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Google Scholar Articles by Fernandez, P. C. Articles by Smith, B. H. PubMed PubMed Citation Articles by Fernandez, P. C. Articles by Smith, B. H.

 Previous Article  |  Next Article 

Behavioral/Systems/Cognitive
Associative Conditioning Tunes Transient Dynamics of Early Olfactory Processing

Patricia C. Fernandez, ^* Fernando F. Locatelli, ^* Nicole Person-Rennell, Gregory Deleo, and Brian H. Smith

Arizona State University, School of Life Sciences, Tempe, Arizona 85287-4501

Correspondence should be addressed to Brian H. Smith at the above address. Email: brianhsmith{at}asu.edu

Odors evoke complex spatiotemporal responses in the insect antennal lobe (AL) and mammalian olfactory bulb. However, the behavioral relevance of spatiotemporal coding remains unclear. In the present work we combined behavioral analyses with calcium imaging of odor induced activity in the honeybee AL to evaluate the relevance of this temporal dimension in the olfactory code. We used a new way for evaluation of odor similarity of binary mixtures in behavioral studies, which involved testing whether a match of odor-sampling time is necessary between training and testing conditions for odor recognition during associative learning. Using graded changes in the similarity of the mixture ratios, we found high correlations between the behavioral generalization across those mixtures and a gradient of activation in AL output. Furthermore, short odor stimuli of 500 ms or less affected how well odors were matched with a memory template, and this time corresponded to a shift from a sampling-time-dependent to a sampling-time-independent memory. Accordingly, 375 ms corresponded to the time required for spatiotemporal AL activity patterns to reach maximal separation according to imaging studies. Finally, we compared spatiotemporal representations of binary mixtures in trained and untrained animals. AL activity was modified by conditioning to improve separation of odor representations. These data suggest that one role of reinforcement is to "tune" the AL such that relevant odors become more discriminable.

---

Received April 13, 2009; revised June 18, 2009; accepted July 8, 2009.

Correspondence should be addressed to Brian H. Smith at the above address. Email: brianhsmith{at}asu.edu

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help