background: the cholinergic system plays an important role in learning and memory. administration of extracts of curcuma longa or its constituent, curcumin, have some roles in cognitive function in animals. the aim of the present study was to investigate the effects of curcumin in preventing spatial performance impairment induced by scopolamine, a cholinergic receptor antagonist, in rats using ...

abstract: introduction & objective: the hippocampal formation is a part of limbic system that plays an important role in memory and learning. the hippocampus is divided into three subfields: ca1, ca2 and ca3. in addition to pyramidal neurons and interneurons, the astrocytes play important roles in hippocampus, probably in memory and learning. in fact, learning needs some instruments for informa...

there are several conflicting evidences showing the effect of morphine on learning and memory processes. in the present study the effect of chronic morphine administration on passive avoidance, active avoidance and spatial learning and memory of morphine dependent male rats using passive avoidance shuttle box and morris water maze tasks were investigated, respectively. male rats received morphi...

Low-frequency (interannual or longer period) climatic variability is of interest, because of its significance for the understanding and prediction of protracted climatic anomalies. Since precipitation is one of the key variables driving various hydrologic processes, it is useful to examine precipitation records to better understand long-term climate dynamics. Here, we use the multi-taper method...

In this paper, we propose an implicit high-order compact (HOC) finite-difference scheme for solving the two-dimensional (2D) unsteady Navier–Stokes (N–S) equations on irregular geometries on orthogonal grids. Our scheme is second order accurate in time and fourth order accurate in space. It is used to solve three pertinent fluid flow problems, namely, the flow decayed by viscosity, the lid-driv...

It is often suggested that the place cells of the hippocampus (and more recently, the grid cells of the entorhinal cortex) furnish a cognitive map. However, this can only be part of the story: (1) the ‘‘hippocampal chart’’ provided by place cells and grid cells differs radically when a rat is placed in different environments and so a higher level organization is needed to link these charts into...

We present a novel Bayesian approach to the problem of value function estimation in continuous state spaces. We define a probabilistic generative model for the value function by imposing a Gaussian prior over value functions and assuming a Gaussian noise model. Due to the Gaussian nature of the random processes involved, the posterior distribution of the value function is also Gaussian and is t...