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Background & Objective: One of the most important principles in education is adopting a teaching method in concordance with objectives, contents and learners. Teaching and learning clinical skills is a challenging aspect of education in field of medicine and allied health profession. Some of the new researchers have shown that video-based instruction has many advantages in comparative to others. But in the domain of the psychomotor learning there is not enough evidence to show that video-based instruction is an effective teaching method. The current study has compared students learning in video-based and demonstration methods. Materials & Methods: An experimental study was conducted on 40 first year nursing and midwifery students. The students were randomly assigned to case (N=20) and control (N=20) groups based on the their course. The data were collected from a pre-test, a post-test and a questionnaire for demographic information. Pre-test was given 24 hours prior to the presentation sessions. Then each group has received one skill with video-based and another skill with demonstration. Skills included the dressing changing and surgical hand washing. After 24 hours post-test was taken with previous criteria. The differences between the pre-test and post-test scores were considered as they are at learning level. Results: The overall learning in the demonstration method was higher than the video-based method (P<0.05). However the scores of students in 2 methods was at acceptable level. The scores of students in the cognitive domain of hand washing by the demonstration were 16.20±1.5 and by the video-based method were 15.25±1. The scores of students in the psychomotor domain of hand washing by the demonstration was 16.85±1.4 and by the video-based method was 15.94±1.4 (P<0.05). The scores of students in the cognitive domain of dressing change by the demonstration was 25.60±1.8 and by the video-based method was 15.50±1. The scores of students in the psychomotor domain of dressing change by the demonstration was 16.78±1.3 and with the video-based was 16.12±1 (P<0.05). Conclusion: The results indicated that demonstration method is more effective in the students learning. However, both video-based and demonstration have led to the high level of cognitive and psychomotor learning. It could be concluded that video-based instruction can be an effective method for replacing the demonstration, especially when there is not access to demonstration, in addition according to the findings, video-based education is a effective methods for transporting knowledge, information and other topics in the cognitive domain. Therefore, considering the cost-effectiveness of video-based instruction and its ease of use, this method can facilitate education in where lack of experienced instructors and equipment is most pronounced.

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Background & Objective: In addition to pyramidal neurons and interneurons, the hippocampus contains Astrocytes that play important roles in regulating ion flux currents, energy production, neurotransmitter release and memory. Learning needs some instrument for information storage and information maintenances mechanisms resemble to memory. The aim of this study was determination of spatial memory effect on the number of astrocytes in rat’s hippocampus. Materials & Methods: In this experimental study, with usage of Morris Water Maze and Reference memory technique, we used 10 male albino wistar rats. 5 rats were in control group and 5 rats in Reference memory group. After histological preparation, the slides were stained with PTAH staining for showing the Astrocytes. Results: The findings of this study showed significant difference in astrocytes number in CA1, CA2 and CA3 area of hippocampus between control and reference memory group. The mean and SD of astrocytes in CA1, CA2 and CA3 of reference memory group were 118.57±25.29, 58.91±23.59 and 116.6±31.14, that they are more than control group with 49±17.29 in CA1, 48.8±25.21 in CA2 and 41.95±11.22 in CA3. Conclusion: We concluded that the number of astrocytes increased due to spatial learning (e.g. reference memory method).

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Background and Objective: Dentate gyrus is a part of hippocampal formation that plays an important role in memory and learning. Astrocytes are one of the important glial cells in nervous tissue that play a more active role in neuronal activity, including regulating ion flux currents, energy production, neurotransmitter release, and synaptogenesis. The aim of this study was to determine the spatial memory effect on the number of astrocytes in Rat’s dentate gyrus. Materials and Methods: This experimental study, was done on 18 male Wistar Rats with using Morris water maze and Reference and Working memory methods. After spatial learning the Rat's brains was carried out and histological preparation was carried out, the slices were with PTAH method. The data analyzed, using T-test and One-way ANOVA. Results: The results showed significant difference in astrocytes number in dentate gyrus area between Reference memory (300.57±5.98) and control (73.73±22.61) groups (P<0.05). The difference between working memory (375.77±4.11) and control groups was significant. Comparing two groups there was a significant difference of number of astrocytes cell between the working memory and Reference memory group (P<0.05). Conclusion: This study showed that spatial learning such as Reference memory and Working memory increase the number of astrocytes in dentate gyrus and this increase can be due to duration of learning.

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Background and Objective: In recent years many studies have reported that aspirin could have beneficial effect on learning and memory in different diseases of central nervous system. The objective of present study was to explore the effect of aspirin on learning and memory of Rats in pentylenetetrazole kindling model. Materials and Methods: In this experimental study Rats were divided randomly into six groups (n=8). Animals in three groups received aspirin (15 and 30 mg/kg, orally) and saline, one week before and during induction of kindling, respectivley. Kindling was induced in these groups by administration of pentylenetetrazole (PTZ: 40 mg/kg, ip). Two groups of animals received only aspirin 25 and 30 mg/kg orally. Other group received only saline throughout the study and served as health control group. After induction of kindling the learning and memory of Rats was tested in shuttle box. Study was divided to three stages of adaptation, acquisition and retention test. Initial Latency (IL) time before electrical shock and Step through latency (STL) time, 20 min or 24h after acquisition was evaluated as learning and memory index. Locomotor activity was also evaluated in open filed test. Results: PTZ kindling significantly decreased Initial Latency and Step through latency time, 20 min or also 24h after acquisition, and aspirin significantly increased these times in kindled animals (p<0.05). Aspirin also had no significant effect on locomotor activity of animals. Conclusion: This study showed that the administration of aspirin to kindled Rats improved learning and memory impairments induced by pentylenetetrazole kindling.

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Background and Objective: Post-traumatic stress disorder (PTSD) impairs spatial learning and memory. Desmopressin acetate ameliorates the cognitive deficits induced by electroconvulsive shock. This study was designed to evaluate the protective effects of Desmopressin acetate on retention of spatial memory deficits induced by post-traumatic stress disorder in rats. Materials and Methods: In this experimental study twenty one male Wistar rats were used. Animals were trained for 5 consecutive days in Morris water maze and then were randomly assigned in three groups (Vehicle + Sham, Saline + PTSD and Desmopressin acetate + PTSD) and tested in a probe 60 sec in 24h after the last acquisition trial. The groups of PTSD+Desmopressin acetate rats and vehicle+sham, saline+PTSD were injected Desmopressin acetate (10 micro gr/kg body weight) and saline (IP), respectively. Injections performed ten minute prior to PTSD and spatial memory was tested ten minutes later. Data were analyzed using SPSS-16, One-Way ANOVA and Tukey tests. Results: The platform location latency of the Desmopressin acetate+PTSD group was significantly shorter (4.24 sec) than the control group (P<0.05) and also, had significantly smaller average proximity values (33.87 cm) compared to the saline+PTSD group (P<0.05). Desmopressin acetate + PTSD spent significantly more time (21.65%) in the target zone (P<0.05). Conclusion: This study indicated that Desmopressin acetate blocks the ability of PTSD to impair spatial memory retention.

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Background and Objective: Recent studies have shown that diabetes induced cognitive dysfunction and impairs learning and memory. Palmatine is an isoquinoline alkaloid, and has multiple pharmacological effects, including anti-diabetic and antioxidant activity. This study was conducted, to evaluate the effect of Palmatine on learning and spatial memory impairment in STZ-induced diabetic rats. Materials and Methods: This experimental study was conducted on the male Wistar rats (n=32) with approximate weight of 240±40 grams. The rats were randomly allocated and were divided into 4 groups (n=8): Control, Palmatine-treated non-diabetic, diabetic and Palmatine-treated diabetic groups. Diabetes was induced by STZ administration at the dose of 55 mg/kg through intraperitoneal route. Palmatine hydrochloride was administered subcutaneous at doses of 10 mg/kg/day 1 week after STZ injection for a period of 6 weeks. Blood samples were taken from the tail vein 1, 3, 5, 7 weeks after STZ injection to measure blood glucose levels. Behavioral tests including spatial recognition and objective recognition were performed at the end of study. Data were analyzed by using Prism-5, one way ANOVA and Tukey tests. Results: In spatial recognition test, the number of entrance in new arm of the Ymaze, in the Palmatine-treated groups significantly increased in compare to diabetic group in both sixth and seventh weeks (P<0.05). Number of rearing in new arm significantly increased in sixth and seventh weeks, compare to the diabetic group (P<0.05). The number of recognition novel objects in the Palmatine-treated diabetic group significantly increased in compare to diabetic group (P<0.05). Conclusion: Palmatine hydrochloride administration for 6 weeks improves cognitive dysfunction in streptozotocin-induced diabetic rats.

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Background and Objective: Diabetes mellitus cause learning, memory and cognitive skills disorders in the long term. This study was conducted to determine the protective effect of silymarin on the learning and memory deficiency in streptozotocin-diabetic rats. Materials and Methods: This experimental study was conducted on 40 male Wistar rats weighing 240-300 grams. The rats were randomly allocated into 5 groups: control, silymarin -treated control (100 mg/kg), diabetic, and two silymarin -treated diabetic groups (50 and 100 mg/kg). Silymarin was daily administered (i.p. and daily) ten days after streptozotocin injection for 4 weeks. Finally, initial (acquisition index) and step-through latencies (retention and recall index) were measured using passive avoidance test and alternation behavior percentage as an index of spatial memory was determined using Y maze. The level of malondialdehyde in the homogenate hippocampal tissue of the animals brains was measured. Data were analyzed using Sigma Stat-3.5, one-way and two-way ANOVA, Tukey, and Kruskall-Wallis tests. Results: A significant reduction of STL was observed in diabetic (P<0.01) and silymarin-treated (50mg/kg) diabetic (P<0.05) groups and this parameter was significantly higher in diabetic group receiving a high dose of silymarin compared to diabetic group (P<0.05). Meanwhile, alternation percentage in diabetic animals was significantly lower than control group (P<0.05) and this index did not show a significant difference in silymarin-treated diabetic groups in comparison with diabetic group. In diabetic rats, there was a significant increase in the tissue level of malondialdehyde (P<0.05) and silymarin treatment with dosage of (100 mg/kg) significantly reduced the level of MDA (P<0.05). Conclusion: This study showed that although long-term administration of silymarin at a high dose (100 mg/kg) affects the ability to store data in memory and to recall it in diabetic animals in passive avoidance test, it does not improve short-term spatial memory in diabetic animals. The beneficial effects of silymarin may be via attenuation of lipid peroxidation in hippocampus tissue.

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Background and Objective: Diabetes mellitus is common endocrine disease cause learning and memory impairment. This study was done to evaluate the effect of quercetin on learning and memory in STZ-induced diabetic rats was investigated. Methods: In this experimental study, 40 male Wistar rats were randomly allocated into five groups: control, quercetin - treated control, diabetic and quercetin - treated diabetic (10 and 20 mg/kg/bw, intraperitoneally) for 14 days. Induction of diabetes was performed using 60 mg/kg/bw of streptozotosin, interapritonally. Passive avoidance and Y-maze tests were used for the evaluation of learning and memory. Results: In passive avoidance learning, there was no significant difference in initial latency between diabetic and treated - diabetic groups. The mean of step latency in control group (383.57±19.26) significantly reduced to 128.86±10.38 in diabetic group (P<0.05). The mean of step latency in the treated diabetic group significantly increased in compare to the diabetic group (P<0.05). Step latency in quercetin - treated diabetic (10 mg/kg/bw) and (20 mg/kg/bw) groups increased to 316.67±23.76 and 397.50±31.21, respectively. The alternative percentage in diabetic group was significantly lower than control group (P<0.05), but in quercetin -treated diabetic groups it was higher than the diabetic group (P<0.05). Conclusion: Administration of quercetin for 14 days enhances the capability of the memory storage, recall and improves short-term spatial memory in STZ-induced diabetic rats.

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Background and Objective: Tamoxifen is one of the selective estrogen receptor modulators that exerts estrogen / anti-estrogen effects in various tissues. This study was done to evaluate the effect of chronic administration of tamoxifen on spatial memory and passive avoidance task in adult male Wistar rats.

Methods: In this experimental study, 48 adult male Wistar rats were randomly divided into control, sham and tamoxifen groups. Animals in sham and tamoxifen groups were received tamoxifen solution and tamoxifen (400mg/kg/day) orally for 35 consecutive days. At the end of treatment, spatial learning and memory of animals was assessed using the Morris water maze task and passive avoidance memory was examined using the shuttle box.

Results: The time spent and distance moved to reach the platform, significantly increased in tamoxifen group compared to controls (P<0.05). In addition, the time spent and distance moved in the target quadrant (in the probe test) significantly reduced in tamoxifen group in compared to controls (P<0.05). In passive avoidance task, tamoxifen significantly decreased the time of the entrance to the dark room compared to control animals (P<0.05).

Conclusion: Long-term administration of tamoxifen impairs spatial learning and memory and passive avoidance memory in rats.

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Background and Objective: Ducrosia anethifolia (Dc.) is a medicinal odor plant contains CNS effective compounds which has been used in Iranian traditional medicine. This study was done to determine the effect of Ducrosia anethifolia (Dc.) Boiss essential oil on spatial learning and memory in adult male rats.

Methods: In this experimental study, 35 wistar adult male rats were randomly allocated into the five groups (n=7) including: control, sham (injected vehicle) and Ducrosia anethifolia (Dc.) Boiss essential oil groups 0.125, 0.25 and 0.5ml/kg/bw, intraperitonally during four days. Morris water maze test was used to assess learning and memory.

Results: Ducrosia anethifolia (Dc.) Boiss essential oil (0.5 ml/kg/bw) was significantly increased escape latency in the second and third (P<0.05) as well as forth (P<0.05) days of acquisition test in compare to control group. In addition latency to find the hidden platform was significantly decreased with 0.25 essential oil in all days except first day (P<0.05) and in essential oil- treated rats at 0.125 ml/kg/bw in the second and third days (P<0.05) in compare to the control group.  Time spent and distance travelled in target zone were significantly increased in Ducrosia anethifolia (Dc.) Boiss essential oil -treated rats (0.5ml/kg/bw) in compare to control group (P<0.05).

Conclusion: Intraperental administration of the Ducrosia anethifolia (Dc.) Boiss essential oil at doses of 0.5 and 0.25 ml/kg/bw during four days can improves spatial learning and memory in adult male rats.

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Background and Objective: Memantine (MEM) an uncompetitive N-methyl-D-aspartate receptor antagonist is used for treatment of patients with Alzheimer disease. This study aimed to examine the effect of Memantine on the spatial learning and memory in electrical lesion’s model of nucleus basalis magnocellularis (NBM) in animal model of Alzheimer's disease.
Methods: In this experimental study, 56 adult male Wistar rats were allocated into eight groups: control group; lesion group, which received bilateral electrically lesion (0.5 mA, 3s) in NBM; sham group (the electrode was entered into the NBM with no lesion); Memantine groups (lesion+1 mg/kg/bw of MEM; lesion+3 mg/kg/bw of  MEM; lesion+5 mg/kg/bw of  MEM; lesion+7 mg/kg/bw of MEM) and Vehicle group (lesion+0.2 mL saline). After one week, animals were trained to perform the Y-maze task for five days. Twenty five days after training, a retention test was performed to determine long-term memory.
Results: The bilateral lesion of NBM impaired the spatial learning compared to the control and sham groups (P<0.05). No effect on spatial learning was seen in saline group compared with the lesion group. The treatment with Memantine in  lesion+MEM 3 mg/kg/bw, lesion+MEM 5mg/kg/bw and lesion+MEM 7mg/kg/bw groups significantly improved spatial learning (P<0.05). Moreover, no significant difference of memory was observed between the results in the 5th day of training and the retention test of the 30th day.
Conclusion: Treatment with memantine improves spatial learning defects in electrical leisions model of NBM of Alzheimer's disease in dose dependent manner in animal model.