Cognition, Behavior, and Memory
Author: Santiago D’hers | Email: sdhers@fbmc.fcen.uba.ar
Santiago D’hers 1°, Santiago Ojea Ramos 1°, Juan Santiago Guidobono 3°, Arturo Romano 2°, Mariana Feld 4°
1° Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), UBA-CONICET
2° Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), UBA-CONICET. Departamento de Fisiología, Biología Molecular y Celular Dr. Héctor Maldonado, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires
3° Laboratorio de Ecología de Poblaciones. Instituto de Ecología, Genética y Evolución de Buenos Aires, UBA-CONICET. Departamento de Ecología, Genética y Evolución. Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires
4° Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), UBA-CONICET. mfeld@fbmc.fcen.uba.ar.
Recognition memory in mice depends on the identification and judgment of prior and near events, involving brain regions such as the medial prefrontal cortex (PFC) and the hippocampus. It can be assessed through simple object exploration tasks. This study delves into Temporal Order Recognition Memory (TORM), induced by a two-session protocol. We observed no significant differences in temporal discrimination between sexes at 2 months of age, but reduced object exploration and better long-term (24-hour) discrimination index in males at 3 months of age. Furthermore, we studied the temporal relation between recognised objects by developing a Temporal Novel Object Recognition (TeNOR) protocol. TeNOR revealed mice’s preference for novel objects over recently familiar ones, but not over old familiar ones.
We also studied Extracellular-signal Regulated Kinase 1/2 (ERK1/2) activation, known for its involvement in learning and memory processes, and observed an increase in ERK2 activation kinetics specifically in the PFC one hour after a single training session (TR). Interestingly, a second TR inhibited this increase, resetting the pathway kinetics and leading to a subsequent rise in activation one hour later.
For data analysis we used glm-models, accounting for the nested structure of each mouse and its housing box. These results lay the foundations for pharmacological intervention studies of ERK1/2 pathway in order to further understand its contribution to temporal memory formation.