The dentate gyrus (DG), a hippocampal subregion, continuously produces new neurons in the adult mammalian brain that become functionally integrated into existing neural circuits. To what extent this form of plasticity contributes to memory functions remains to be elucidated. Using mapping of activity-dependent gene expression, we visualized in mice injected with the birthdating marker 5-bromo-2...

Anterior/posterior long axis specialization is thought to underlie the organization of the hippocampus. However it remains unclear whether antagonistic mechanisms differentially modulate processing of spatial information within the hippocampus. We used fMRI and a virtual reality 3D paradigm to study encoding and retrieval of spatial memory during active visuospatial navigation, requiring positi...

The rapid advances in information retrieval, especially with visualisation-oriented user interface design, highlight the need for an understanding of the interplay between cognitive abilities of users and the design of visual user interfaces. In this study, we focus on two aspects of memory abilities of users in attempts to reveal their roles in facilitating information-seeking tasks. In partic...

To determine whether memory is processed in a localized or distributed manner by the hippocampus, we inactivated small regions of the structure in pretrained rats before a retention test. Ibotenic acid-induced lesions removing 40% of the hippocampal tissue disrupted retrieval of spatial memory in a water maze but failed to affect new learning or retrieval of a task that was acquired postoperati...

Functional neuroimaging studies of episodic memory retrieval generally measure brain activity while participants remember items encountered in the laboratory ("controlled laboratory condition") or events from their own life ("open autobiographical condition"). Differences in activation between these conditions may reflect differences in retrieval processes, memory remoteness, emotional content,...

Previous evidence has suggested a functional-anatomic dissociation between conscious and nonconscious processing during retrieval where early visual regions BA17/18 are associated with nonconscious processing and late visual regions BA19/37 are associated with conscious processing. However, evidence for this dissociation has only been observed using a limited number of experimental paradigms. I...

Attentional orienting and memory are intrinsically bound, but their interaction has rarely been investigated. Here we introduce an experimental paradigm using naturalistic scenes to investigate how long-term memory can guide spatial attention and thereby enhance identification of events in the perceptual domain. In the task, stable memories of objects embedded within complex scenes guide spatia...

Introduction: Lead (Pb) is a neurotoxin that its different effects on the central nervous system are well-known. Previous studies have reported the potent effects of vitamin C on memory.The present study was undertaken to evaluate the protective effects of vitamin C against leadinduced amnesia. Methods: Male Wistar rats were divided into 4 groups: the control (saline), negative contr...

Networks of interconnected neocortical representations of prior knowledge, "schemas," facilitate memory for congruent information. This facilitation is thought to be mediated by augmented encoding and accelerated consolidation. However, it is less clear how schema affects retrieval. Rodent and human studies to date suggest that schema-related memories are differently retrieved. However, these s...

Introduction: Protein kinase M zeta (PKMζ) is assumed to be actively involved in retainig long-term potentiation. The goal of this study was to investigate the role of PKMζ in basolateral amygdala (BLA) upon acquisition, consolidation, retention and retrieval of memory using a specific inhibitor of PKMζ. Methods: Sixty male wistar rats underwent stereotaxic surgery and were cannu...