Abstract
The entorhinal cortex is the primary interface between the hippocampal formation and neocortical sources of sensory information. Although much is known about the cells of origin, termination patterns, and topography of the entorhinal projections to other fields of the adult hippocampal formation, very little is known about the development of these pathways, particularly in the human or nonhuman primate. We have carried out experiments in which the anterograde tracers 3H-amino acids, biotinylated dextran amine, and Phaseolus vulgaris leucoagglutinin were injected into the entorhinal cortex in 2-week-old rhesus monkeys (Macaca mulatta). We found that the three fiber bundles originating from the entorhinal cortex (the perforant path, the alvear pathway, and the commissural connection) are all established by 2 weeks of age. Fundamental features of the laminar and topographic distribution of these pathways are also similar to those in adults. There is evidence, however, that some of these projections may be more extensive in the neonate than in the mature brain. The homotopic commissural projections from the entorhinal cortex, for example, originate from a larger region within the entorhinal cortex and terminate much more densely in layer I of the contralateral entorhinal cortex than in the adult. These findings indicate that the overall topographical organization of the main cortical afferent pathways to the dentate gyrus and hippocampus are established by birth. These findings add to the growing body of literature on the development of the primate hippocampal formation and will facilitate further investigations on the development of episodic memory.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1485-1505 |
| Number of pages | 21 |
| Journal | Journal of Comparative Neurology |
| Volume | 522 |
| Issue number | 7 |
| DOIs | |
| State | Published - May 1 2014 |
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Keywords
- Development
- Medial temporal lobe
- Perforant path
- Primate
- Topographical and laminar organization
ASJC Scopus subject areas
- Neuroscience(all)
- Medicine(all)
Cite this
An analysis of entorhinal cortex projections to the dentate gyrus, hippocampus, and subiculum of the neonatal macaque monkey. / Amaral, David G; Kondo, Hideki; Lavenex, Pierre.
In: Journal of Comparative Neurology, Vol. 522, No. 7, 01.05.2014, p. 1485-1505.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - An analysis of entorhinal cortex projections to the dentate gyrus, hippocampus, and subiculum of the neonatal macaque monkey
AU - Amaral, David G
AU - Kondo, Hideki
AU - Lavenex, Pierre
PY - 2014/5/1
Y1 - 2014/5/1
N2 - The entorhinal cortex is the primary interface between the hippocampal formation and neocortical sources of sensory information. Although much is known about the cells of origin, termination patterns, and topography of the entorhinal projections to other fields of the adult hippocampal formation, very little is known about the development of these pathways, particularly in the human or nonhuman primate. We have carried out experiments in which the anterograde tracers 3H-amino acids, biotinylated dextran amine, and Phaseolus vulgaris leucoagglutinin were injected into the entorhinal cortex in 2-week-old rhesus monkeys (Macaca mulatta). We found that the three fiber bundles originating from the entorhinal cortex (the perforant path, the alvear pathway, and the commissural connection) are all established by 2 weeks of age. Fundamental features of the laminar and topographic distribution of these pathways are also similar to those in adults. There is evidence, however, that some of these projections may be more extensive in the neonate than in the mature brain. The homotopic commissural projections from the entorhinal cortex, for example, originate from a larger region within the entorhinal cortex and terminate much more densely in layer I of the contralateral entorhinal cortex than in the adult. These findings indicate that the overall topographical organization of the main cortical afferent pathways to the dentate gyrus and hippocampus are established by birth. These findings add to the growing body of literature on the development of the primate hippocampal formation and will facilitate further investigations on the development of episodic memory.
AB - The entorhinal cortex is the primary interface between the hippocampal formation and neocortical sources of sensory information. Although much is known about the cells of origin, termination patterns, and topography of the entorhinal projections to other fields of the adult hippocampal formation, very little is known about the development of these pathways, particularly in the human or nonhuman primate. We have carried out experiments in which the anterograde tracers 3H-amino acids, biotinylated dextran amine, and Phaseolus vulgaris leucoagglutinin were injected into the entorhinal cortex in 2-week-old rhesus monkeys (Macaca mulatta). We found that the three fiber bundles originating from the entorhinal cortex (the perforant path, the alvear pathway, and the commissural connection) are all established by 2 weeks of age. Fundamental features of the laminar and topographic distribution of these pathways are also similar to those in adults. There is evidence, however, that some of these projections may be more extensive in the neonate than in the mature brain. The homotopic commissural projections from the entorhinal cortex, for example, originate from a larger region within the entorhinal cortex and terminate much more densely in layer I of the contralateral entorhinal cortex than in the adult. These findings indicate that the overall topographical organization of the main cortical afferent pathways to the dentate gyrus and hippocampus are established by birth. These findings add to the growing body of literature on the development of the primate hippocampal formation and will facilitate further investigations on the development of episodic memory.
KW - Development
KW - Medial temporal lobe
KW - Perforant path
KW - Primate
KW - Topographical and laminar organization
UR - http://www.scopus.com/inward/record.url?scp=84896273094&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84896273094&partnerID=8YFLogxK
U2 - 10.1002/cne.23469
DO - 10.1002/cne.23469
M3 - Article
VL - 522
SP - 1485
EP - 1505
JO - Journal of Comparative Neurology
JF - Journal of Comparative Neurology
SN - 0021-9967
IS - 7
ER -