Differential encoding of behavior and spatial context in deep and superficial layers of the neocortex.
Rodent hippocampal activity is correlated with spatial and behavioral context, but how context affects coding in association neocortex is not well understood. The cellular distribution of the neural activity-regulated immediate-early gene Arc was used to monitor the activity history of cells in CA1, and in deep and superficial layers of posterior parietal and gustatory cortices (which encode movement and taste, respectively), during two behavioral epochs in which spatial and behavioral context were independently manipulated while gustatory input was held constant. Under conditions in which the hippocampus strongly differentiated behavioral and spatial contexts, deep parietal and gustatory layers did not discriminate between spatial contexts, whereas superficial layers in both neocortical regions discriminated well. Deep parietal cells discriminated behavioral context, whereas deep gustatory cortex neurons encoded the two conditions identically. Increased context sensitivity of superficial neocortical layers, which receive more hippocampal outflow, may reflect a general principle of neocortical organization for memory retrieval.
Burke
Sara N
SN
Neural Systems, Memory, and Aging Division, Life Sciences North Building, Room 384, University of Arizona, Tucson, AZ 85724, USA.
Chawla
Monica K
MK
Penner
Marsha R
MR
Crowell
Brynne E
BE
Worley
Paul F
PF
Barnes
Carol A
CA
McNaughton
Bruce L
BL
D000818:Animals; D003598:Cytoskeletal Proteins; D017874:Immediate-Early Proteins / Q000096:biosynthesis; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D019579:Neocortex / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000096:biosynthesis; D009474:Neurons / Q000378:metabolism*; D051381:Rats; D011916:Rats, Inbred F344; D013037:Spatial Behavior / Q000502:physiology*; D013649:Taste / Q000502:physiology*
D003598:Cytoskeletal Proteins; D017874:Immediate-Early Proteins; D009419:Nerve Tissue Proteins; C092069:activity regulated cytoskeletal-associated protein