Development of a retrieval-induced forgetting paradigm in rodents to model adaptive forgetting in the mammalian brain

GALLO FRANCISCO; MORICI FACUNDO; MIRANDA MAGDALENA; BEKINSCHTEIN, PEDRO; NOELIA WEISSTAUB

huerta grande

Congreso; XXVIII Congreso Anual de la Sociedad Argentina de Investigaciones en neurocienicas; 2014

Sociedad Argentina de Investigaciones en Neurociencias

Over a century of research has presumed that forgetting reflects passive mechanisms such as decay and interference. In the last two decades, however, a growing human literature on retrieval-induced forgetting (RIF) has pointed to inhibitory control processes that resolve retrieval competition as a cause of adaptive forgetting. However, the lack of animal-based models for RIF has precluded the understanding of the neurobiological mechanisms. Using spontaneous recognition memory in rats, we have successfully developed a rodent paradigm for RIF. We were able to show that forgetting of an item associated with a particular context happens under conditions that cause competition between memory traces for two items that share a particular retrieval cue. Forgetting is long lasting and independent of the selected retrieval cue and it is controlled by the medial Prefrontal Cortex (mPFC) in rats, homologue to the Dorsolateral Prefrontal region in humans. Our results provide evidence that adaptive forgetting occurs in non-human animals and that homologue regions are required for it. These results suggest that this type of forgetting is achieved by top down inhibition exerted by mPFC over the brain structures that store the memory traces