TY - JOUR
T1 - Neural Population Evidence of Functional Heterogeneity along the CA3 Transverse Axis
T2 - Pattern Completion versus Pattern Separation
AU - Lee, Heekyung
AU - Wang, Cheng
AU - Deshmukh, Sachin S.
AU - Knierim, James J.
N1 - Funding Information:
We thank I. Lee, E.D. Roth, X. Yu, and J.P. Neunuebel for use of their experimental data; J.D. Monaco for assistance with data analysis; K. Bandeen-Roche for advice on statistics; F. Savelli, G. Rao, and D. Yoganarasimha for assistance in data collection; and J.L. Johnson, V. Puliyadi, and A. Smolinsky for technical assistance. This work was supported by NIH grants R01 NS039456 and R01 MH094146, and by a grant from the Johns Hopkins University Brain Sciences Institute.
Publisher Copyright:
© 2015 Elsevier Inc.
PY - 2015/9/2
Y1 - 2015/9/2
N2 - Classical theories of associative memory model CA3 as a homogeneous attractor network because of its strong recurrent circuitry. However, anatomical gradients suggest a functional diversity along the CA3 transverse axis. We examined the neural population coherence along this axis, when the local and global spatial reference frames were put in conflict with each other. Proximal CA3 (near the dentate gyrus), where the recurrent collaterals are the weakest, showed degraded representations, similar to the pattern separation shown by the dentate gyrus. Distal CA3 (near CA2), where the recurrent collaterals are the strongest, maintained coherent representations in the conflict situation, resembling the classic attractor network system. CA2 also maintained coherent representations. This dissociation between proximal and distal CA3 provides strong evidence that the recurrent collateral system underlies the associative network functions of CA3, with a separate role of proximal CA3 in pattern separation.
AB - Classical theories of associative memory model CA3 as a homogeneous attractor network because of its strong recurrent circuitry. However, anatomical gradients suggest a functional diversity along the CA3 transverse axis. We examined the neural population coherence along this axis, when the local and global spatial reference frames were put in conflict with each other. Proximal CA3 (near the dentate gyrus), where the recurrent collaterals are the weakest, showed degraded representations, similar to the pattern separation shown by the dentate gyrus. Distal CA3 (near CA2), where the recurrent collaterals are the strongest, maintained coherent representations in the conflict situation, resembling the classic attractor network system. CA2 also maintained coherent representations. This dissociation between proximal and distal CA3 provides strong evidence that the recurrent collateral system underlies the associative network functions of CA3, with a separate role of proximal CA3 in pattern separation.
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U2 - 10.1016/j.neuron.2015.07.012
DO - 10.1016/j.neuron.2015.07.012
M3 - Article
C2 - 26298276
AN - SCOPUS:84940584025
SN - 0896-6273
VL - 87
SP - 1093
EP - 1105
JO - Neuron
JF - Neuron
IS - 5
ER -