Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.
Active Motif, Inc

Site Tools

  • AAAS
  • Subscribe
  • Feedback

Site Search

Search Advanced

Science 21 March 2008:
Vol. 319. no. 5870, pp. 1640 - 1642
DOI: 10.1126/science.1152882
Prev | Table of Contents | Next

Research Articles

Pattern Separation in the Human Hippocampal CA3 and Dentate Gyrus

Arnold Bakker,1 C. Brock Kirwan,2 Michael Miller,3 Craig E. L. Stark1,4*

Pattern separation, the process of transforming similar representations or memories into highly dissimilar, nonoverlapping representations, is a key component of many functions ascribed to the hippocampus. Computational models have stressed the role of the hippocampus and, in particular, the dentate gyrus and its projections into the CA3 subregion in pattern separation. We used high-resolution (1.5-millimeter isotropic voxels) functional magnetic resonance imaging to measure brain activity during incidental memory encoding. Although activity consistent with a bias toward pattern completion was observed in CA1, the subiculum, and the entorhinal and parahippocampal cortices, activity consistent with a strong bias toward pattern separation was observed in, and limited to, the CA3/dentate gyrus. These results provide compelling evidence of a key role of the human CA3/dentate gyrus in pattern separation.

1 Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, USA.
2 Institute for Neural Computation, University of California at San Diego, San Diego, CA, USA.
3 Center for Imaging Science, Johns Hopkins University, Baltimore, MD, USA.
4 Center for the Neurobiology of Learning and Memory and Department of Neurobiology and Behavior, University of California at Irvine, Irvine, CA, USA.

* To whom correspondence should be addressed. E-mail: cestark{at}uci.edu

Read the Full Text

ADVERTISEMENT
Click Me!

ADVERTISEMENT
Click Me!

To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)