cornus ammonis [CA]-3

Introduction

Pole of the cornu ammonis that interlocks with the dentate gyrus.

Afferents

• other levels of CA3 (along rostral caudal axis)
• mossy fibers from the dentate gyrus (hippocampal mossy fiber pathway)
• entorhinal cortex (perforant pathway)

Efferents

• other levels of CA3 (along rostral caudal axis)
• CA1 (Schaeffer collaterals)
• subcortical (see hippocampal efferents, subcortical)
  • septal nuclei
  • anterior nucleus of thalamus
  • mammillary body
  • claustrum
  • amygdala
  • nucleus accumbens
  • striatum (caudate/putamen)
  • hypothalamus

Comparative biology

• CA3 NMDA receptors required for associative memory recall in mice
• in normal rats a functional gradient occurs in CA3 along the transverse axis, as pattern-separated outputs (proximal CA3) with transition to pattern- completed outputs (distal CA3)
  • normal transition from pattern separation to pattern completion along the CA3 transverse axis is disrupted in aged memory-impaired rats

More general terms

• brain structure

Additional terms

• entorhinal cortex (Brodmann's area 28)
• hippocampal efferents, subcortical
• hippocampal mossy fiber pathway
• Schaeffer collaterals
• septal nucleus

Component of

• cornus ammonis (Ammon's horn)