Background and Aim: Neurodegenerative diseases such as Alzheimer's disease are the most common cause of memory impairment worldwide. No effective drug treatment has been found to improve the memory deficit and quality of life of these patients. Considering the effects of MPL on improving memory in Alzheimer's disease and hippocampal ischemia, this study investigated the effect of monophosphoryl lipid A (MPL) on the Spatial memory of rats. Methods: This study was conducted on 48 adult male Wistar rats (45-day-old) weighing 250-270 grams, which were randomly divided into two groups of “7 days” and “28 days”. Each group was divided into three subgroups (n = 8) including control, sham, and drug. The Spatial learning and memory were assessed by the Morris water maze. Animals were trained to find the hidden platform in the maze for five days and 4 sessions every day. The drug was injected into the lateral cerebral ventricle at a dose of 1 µg per 5 µL per rat, 20 min after surgery. The time spent and the distance traveled in the target quadrant were assessed on the seventh and twenty-eighth days after the last day of learning. Results: No significant difference was found between the groups in the time spent and distance traveled in the target quadrant during the learning phase. Furthermore, there was no significant difference between groups in memory recall at both 7 days and 28 days after the training period (p > 0.05). Conclusion: In our study, MPL 1 µg/5 µL/rat did not affect the Spatial memory of rats. ‎

Objectives: The hippocampus has been implicated in many learning and memory functions including Spatial memory. Leptin is a peptide hormone secreted by adipose tissue. Some studies have also suggested that leptin affect learning and memory. The present study is scheduled to investigate the effect of intraperitoneal (IP) injection of different doses of leptin on Spatial memory formation. Methods: 60 male rats were divided into 6 groups in our experiments: (1) control, (2) sham, and (3), (4), (5), (6) intraperitoneal injection of 0.05, 0.1, 0.25 and 0.5 mg/kg doses of leptin respectively. All groups were trained in Morris water maze for two days. Learning parameters were compared between groups. Results: Our results showed there were significant differences between sham group and test groups in Spatial learning. Conclusion: Together our findings suggest that intraperitoneally injection of leptin improved Spatial memory in rat. Leptin shows its highest effect with medium doses.

There are two approaches for simulating memory as well as learning in artificial intelligence; the functionalistic approach and the cognitive approach. The necessary condition to put the second approach into account is to provide a model of brain activity that contains a quite good congruence with observational facts such as mistakes and forgotten experiences. Given that human memory has a solid core that includes the components of our identity, our family and our hometown, the major and determinative events of our lives, and the countless repeated and accepted facts of our culture, the more we go to the peripheral spots the data becomes flimsier and more easily exposed to oblivion. It was essential to propose a model in which the topographical differences are quite distinguishable. In our proposed model, we have translated this topographical situation into quantities, which are attributed to the nodes. The result is an edge-weighted graph with mass-based values on the nodes which demonstrates the importance of each atomic proposition, as a truth, for an intelligent being. Furthermore, it dynamically develops and modifies, and in successive phases, it changes the mass of the nodes and weight of the edges depending on gathered inputs from the environment.

This study was an attempt to investigate the relationship between Spatial memory and Symptoms of Neuroticism in men and women visitors of a flower garden. The participants were chosen by an available sampling method among people who visited flower garden, located in Isfahan, Iran in October 2016. Subjects (woman=36, man=24) were asked to specify approximate locations of eight sites in the flower Garden on the incomplete map of flower garden after visiting the garden. Then, the subjects filled a demographic questionnaire and a short form of Eysenck introversion-extraversion questionnaire. The results showed that the means of Spatial memory in men are significantly more than those of women (F= 11. 46, p<0. 05) and also, neuroticism in men is significantly less than that in women (F=7. 22, P<0. 05). Furthermore, positive relationship between age and Spatial memory (r= 0. 41, p<0. 01) and negative relationship between neuroticism and Spatial memory have been discovered (r=-0. 59, p<0. 01). According to the results, it can be concluded that neuroticism avoids paying attention to the environment and it causes memory function slump.

Introduction: Previous study indicated that adrenocortical glucocrticoids are effectiveness on memory storage in emotional state. There are moderate density of glucocorticoid receptors in basolateral amygdale (BLA) that may be involved in learning and memory. The present experiment examined the role of glucocorticoid antagonist receptor into the basolateral amygdale (BLA) on Spatial memory in Morris water Maze task.Materials and Methods: Male Long-Evans strain rats were surgically implanted bilaterally with cannulae aimed at the BLA in the brain and were trained to Morris water Maze task. RU-38486 (3 ng/0.6 ml per side) as a glucocorticoid antagonist were injected bilaterally into BLA pre-training and immediately, 60 and 120 min after training and pri retrieval test. The latency time to the fine plexy glass platform and the length of swimming were used to measure the Spatial memory.Results: Results indicated that infusion of glucocorticoid antagonist pretraining and immediately and 60 min, but not 120 min after training into BLA significantly impaired retention performance. Injection of the drug before retrieval test did not any significant effect on animal performance.Conclusion: The above results show that glucocorticoid receptors plays an important role in acquisition and consolidation of Spatial memory in Morris water Maze task at least 60 min after training.