5-HT2a receptor in prefrontal cortex participates in the resolution of retroactive interference between object memories during consolidation

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

toronto

Congreso; 2019; 2019

Canadian Society for neuroscience

Historically, memory consolidation was associated withthe activity of the medial temporal lobe. However, recently, it was shown thatthe Prefrontal cortex (PFC) also plays a role, particularly when interferinginformation is presented. The serotoninergic modulation of PFC has been linkedwith attentional and executive processes. Though, little is known about therole of this system during the consolidation of interfering memory traces. Theobject-in-context memory task (OIC) is a recognition protocol in which twoobject-context associations are generated. Then, depending on the strength ofthe memory traces, interference between both memories could occurred. Since PFCserotonin type 2a receptor (5-HT2AR) activity has been shown to help preventmemory interference during retrieval, we wanted to evaluate if it participatesin the control of memory interference during consolidation.   We selectively modulated PFC 5-HT2AR activityafter OIC-memory acquisition in rats. We observed that activation of 5-HT2ARwas required for the resolution of the OIC task only after a weak training thatcould not be retrieved 24 hs later. Moreover, the PFC 5-HT2AR activity seemedto be required only when two memory consolidation processes were triggeredwithin a specific time window.However, blockade of 5-HT2AR did not affectOIC-memory consolidation when animals generated a long-lasting memory.  In summary, our results suggest that the PFC5-HT2AR activity prevent memory interference  in a time and strength dependent way.