Perirhinal and Postrhinal Contributions to Remote Memory for Context

• DOI: 10.1523/jneurosci.3781-04.2004
• Publication Date: 2004-12-08T21:54:14Z
• Authors: Rebecca D. Burwell; David J. Bucci; Matthew R. Sanborn; Michael J. Jutras
• Keywords: Perirhinal cortex; Entorhinal cortex

The perirhinal (PER) and postrhinal (POR) cortices, two components of the medial temporal lobe memory system, are reciprocally connected with hippocampus both directly via entorhinal cortex. Damage to PER or POR before shortly after training on a contextual fear conditioning task causes deficits in subsequent expression fear, implicating these regions acquisition memory. Here, we examined contribution processing remotely learned information. Male Long-Evans rats were trained an unsignaled paradigm. After training, received bilateral neurotoxic lesions sham control surgeries at three different training-to-lesion intervals: 1, 28, 100 d training. Two weeks surgery, lesioned returned context assess as measured by freezing. Rats damage froze significantly less than but not from each other. severity deficit did differ across intervals for any group. This pattern differs that posttraining hippocampal lesions, which longer produce more fear-conditioned freezing shorter intervals. In absence such retrograde gradient present study, our interpretation is have ongoing role storage retrieval representations context. Alternatively, may be involved extended consolidation process becomes apparent beyond learning.