Several studies in rats have shown activation of cortical regions and concurrent deactivation of the hippocampus during the retrieval of spatial memory, as the consolidation process progresses. To determine whether during this post-learning period of memory reorganization, spatial memories are transformed from a specific to a more generic representation, in Experiment 1 we compare remote spatia...

Recent studies have shown that the anterior (ATN) and lateral thalamic nuclei (including the intralaminar nuclei; ILN/LT) play different roles in memory processes. These nuclei have prominent direct and indirect connections with the hippocampal system and/or the prefrontal cortex and may thus participate in the time-dependent reorganization of memory traces during systems-level consolidation. W...

Acute stress impairs memory retrieval and facilitates the induction of long-term depression (LTD) in the hippocampal CA1 region of the adult rodent brain. However, whether such alterations in synaptic plasticity cause the behavioral effects of stress is not known. Here, we report that two selective inhibitors of the induction or expression of stress-enabled, N-methyl-D-aspartate receptor-depend...

There is little consensus regarding the specific processes responsible for encoding, maintenance, and retrieval of information in visuo-spatial working memory (VSWM). One influential theory is that VSWM may involve activation of the eye-movement (oculomotor) system. In this study we experimentally prevented healthy participants from planning or executing saccadic eye-movements during the encodi...

introduction: kisspeptin-13 (kp-13) is a novel endogenous factor, increases synaptic transmission and is involved in several behavioral functions such as anxiety, locomotion, epilepsy and avoidance learning. however, the role of this peptide on cognition has not been well clarified yet. here we studied the effect of kisspeptin-13 pretreatment on spatial learning and also interaction with cholin...

Whether or not the hippocampus participates in semantic memory retrieval has been the focus of much debate in the literature. However, few neuroimaging studies have directly compared hippocampal activation during semantic and episodic retrieval tasks that are well matched in all respects other than the source of the retrieved information. In Experiment 1, we compared hippocampal fMRI activation...

Episodic memory provides information about the "when" of events as well as "what" and "where" they happened. Using functional imaging, we investigated the domain specificity of retrieval-related processes following encoding of complex, naturalistic events. Subjects watched a 42-min TV episode, and 24h later, made discriminative choices of scenes from the clip during fMRI. Subjects were presente...