Development of the spatial representation system in the rat.
In the adult brain, space and orientation are represented by an elaborate hippocampal-parahippocampal circuit consisting of head-direction cells, place cells, and grid cells. We report that a rudimentary map of space is already present when 2 1/2-week-old rat pups explore an open environment outside the nest for the first time. Head-direction cells in the pre- and parasubiculum have adultlike properties from the beginning. Place and grid cells are also present but evolve more gradually. Grid cells show the slowest development. The gradual refinement of the spatial representation is accompanied by an increase in network synchrony among entorhinal stellate cells. The presence of adultlike directional signals at the onset of navigation raises the possibility that such signals are instrumental in setting up networks for place and grid representation.
Langston
Rosamund F
RF
Kavli Institute for Systems Neuroscience and Centre for the Biology of Memory, Medical Technical Research Center, Norwegian University of Science and Technology, Olav Kyrres gate 9, 7489 Trondheim, Norway.
Ainge
James A
JA
Couey
Jonathan J
JJ
Canto
Cathrin B
CB
Bjerknes
Tale L
TL
Witter
Menno P
MP
Moser
Edvard I
EI
Moser
May-Britt
MB
D000200:Action Potentials; D000375:Aging; D000818:Animals; D001931:Brain Mapping; D056547:CA1 Region, Hippocampal / Q000502:physiology*; D004567:Electrodes, Implanted; D018728:Entorhinal Cortex / Q000166:cytology / Q000502:physiology*; D005106:Exploratory Behavior; D005260:Female; D008297:Male; D009415:Nerve Net / Q000502:physiology; D009434:Neural Pathways; D009474:Neurons / Q000502:physiology*; D009949:Orientation; D020534:Parahippocampal Gyrus / Q000166:cytology / Q000502:physiology*; D018408:Patch-Clamp Techniques; D051381:Rats; D020318:Rats, Long-Evans; D013028:Space Perception; D013037:Spatial Behavior