immediately deep to immediately superficial to layer of hippocampus hippocampus pyramidal layer hippocampus stratum radiatum FMA:83894 UBERON:0005372 stratum radiatum radiate layer of hippocampus MA:0000959 EMAPA:35413 The layer located immediately above the pyramidal cell layer in CA2 and CA1 and superficial to the stratum lucidum in CA3. Suprapyramidal region in which CA3 to CA3 associational connections and CA3 to CA1 Schaffer collateral connections are located. BAMS:Rad stratum radiatum of the hippocampus BIRNLEX:1298 hippocampus stratum lucidum