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

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

The Journal of Neuroscience, July 2, 2008, 28(27):6858-6871; doi:10.1523/JNEUROSCI.5684-07.2008

This Article Full Text Full Text (PDF) 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 ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Google Scholar Articles by Fiete, I. R. Articles by Brookings, T. PubMed PubMed Citation Articles by Fiete, I. R. Articles by Brookings, T.

 Previous Article  |  Next Article 

Behavioral/Systems/Cognitive
What Grid Cells Convey about Rat Location

Ila R. Fiete,^1,3 Yoram Burak,^1,4 and Ted Brookings^2,5

¹Kavli Institute for Theoretical Physics and ²Department of Physics, University of California, Santa Barbara, Santa Barbara, California 93106, ³Broad Fellows Program, Computation and Neural Systems, California Institute of Technology, Pasadena, California 91125, ⁴Swartz Fellows Program, Center for Brain Science, Harvard University, Cambridge, Massachusetts 02138, and ⁵Volen Center, Department of Biology, Brandeis University, Waltham, Massachusetts 02454

Correspondence should be addressed to Ila R. Fiete, Division of Biology, 216-76, California Institute of Technology, Pasadena, CA 91125. Email: ilafiete{at}caltech.edu

We characterize the relationship between the simultaneously recorded quantities of rodent grid cell firing and the position of the rat. The formalization reveals various properties of grid cell activity when considered as a neural code for representing and updating estimates of the rat's location. We show that, although the spatially periodic response of grid cells appears wasteful, the code is fully combinatorial in capacity. The resulting range for unambiguous position representation is vastly greater than the 1–10 m periods of individual lattices, allowing for unique high-resolution position specification over the behavioral foraging ranges of rats, with excess capacity that could be used for error correction. Next, we show that the merits of the grid cell code for position representation extend well beyond capacity and include arithmetic properties that facilitate position updating. We conclude by considering the numerous implications, for downstream readouts and experimental tests, of the properties of the grid cell code.

Key words: navigation; dMEC; entorhinal; hippocampus; spatial perception; information; path integration; theory

---

Received Jan. 4, 2008; revised April 7, 2008; accepted April 28, 2008.

Correspondence should be addressed to Ila R. Fiete, Division of Biology, 216-76, California Institute of Technology, Pasadena, CA 91125. Email: ilafiete{at}caltech.edu

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help