Paradoxical influence of hippocampal neurogenesis on working memory.
To explore the function of adult hippocampal neurogenesis, we ablated cell proliferation by using two independent and complementary methods: (i) a focal hippocampal irradiation and (ii) an inducible and reversible genetic elimination of neural progenitor cells. Previous studies using these methods found a weakening of contextual fear conditioning but no change in spatial reference memory, suggesting a supportive role for neurogenesis in some, but not all, hippocampal-dependent memory tasks. In the present study, we examined hippocampal-dependent and -independent working memory using different radial maze tasks. Surprisingly, ablating neurogenesis caused an improvement of hippocampal-dependent working memory when repetitive information was presented in a single day. These findings suggest that adult-born cells in the dentate gyrus have different, and in some cases, opposite roles in distinct types of memory.
Saxe
Michael D
MD
Center for Neurobiology and Behavior and Howard Hughes Medical Institute, Columbia University, 722 West 168th Street, New York, NY 10032, USA.
Malleret
Gaël
G
Vronskaya
Svetlana
S
Mendez
Indira
I
Garcia
A Denise
AD
Sofroniew
Michael V
MV
Kandel
Eric R
ER
Hen
René
R
D000818:Animals; D049109:Cell Proliferation; D006624:Hippocampus / Q000378:metabolism / Q000473:pathology* / Q000502:physiology*; D008297:Male; D018782:Maze Learning; D008568:Memory; D008569:Memory Disorders / Q000473:pathology; D008570:Memory, Short-Term; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009474:Neurons / Q000378:metabolism*; D013234:Stem Cells / Q000166:cytology; D019076:Transgenes