Tangential Fibers in Laminae I of cerebral cortex do they exist?

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Graeme E. Smith
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Tangential Fibers in Laminae I of cerebral cortex do they exist?

In Eccles article in 1983 he describes a horizontal (Tangential Fibers) system in Laminae I,  of the Cerebral Cortex, In Marr's artilcle in 1970 his diagram clearly shows horizontal parallel fibers that connect Layer 1 mossy dendrite neurons to the Apical Dendrites of layer 2/3 Pyramidal cells. Is this an accurate depiction?
 

Graeme E. Smith
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Ok, slight correction, Eccles

Ok, slight correction, Eccles noted that in adult brains the mossy dendrite neurons in laminae I were sparse, which if Marr's description was accurate suggests that the population of mossy dendrites reduces over the life of the organism. this eliminates the mossy dendrites as the source of tangential fibers and requires that there be involvement of the 4th layer spiny type neurons to overcome the inhibitive role of the martinotti cells. (I got a look at a photocopy of the original article). If Laminae I is involved in learning, then it could be that the reduction in the population of mossy dendrite cells over the life of the organism might suggest that they become redundant once the 2/3 layer pyramidal neurons learn to react to patterns of inputs from layer 4?