Introduction: The role of ovarian hormones and nitric oxide (NO) in learning and memory and their interaction has been widely investigated. The present study carried out to evaluate different effect of L-NAME on spatial learning and memory of ovariectomized (OVX) and sham operated rats.

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Introduction: Cholinergic systems are involved in learning and memory. Scopolamine, a muscarinic acetylcholine receptor antagonist, is used as a standard/ reference drug for inducing cognitive deficits in healthy humans and animals. The purpose of this study was to evaluate the effects of scopolamine on avoidance memory and number of neurons in rat’s hippocampus. .

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Introduction:

Previous studies have suggested that the cerebellum is a primary site of motor learning. The cerebellar cortex has a particular glial architecture with large astroglial cells. In addition, more recent works have revealed that astrocytes play a more active role in neuronal activity. The aim of this study was to evaluate the number of astrocytes in the molecular layer of rat's cerebellum after spatial learning. 21 male albino wistar rats were used in this study. Reference and working memory methods of Morris Water Maze (MWM) were used. Following behavioral testing, animals were decapitated under diethyl ether anesthesia. Brains were removed and fixed for 2 weeks for histological assessment. Finally, 7 μm thick coronal slices were cut and stained with PTAH staining for showing the astrocytes.

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Introduction: The role of ovarian hormones and nitric oxide (NO) on oxidative damage in brain tissues as well as learning and memory has been widely investigated.

The present study was carried out to evaluate the effect of the precursor of NO, L-Arginine on learning and brain damage due to oxidative stress in ovariectomized (OVX) rats.

Methods: Thirty -two rats were divided into four groups: 1) Sham, 2) OVX, 3) Sham-L-Arginine (Sham-LA) and 4) OVX-L-Arginine(OVX-LA).  The animals of sham- LA and OVX-LA were treated with 500 mg/kg of L-Arginine. The animals in Sham and OVX groups received 1 ml/kg saline. The animals were tested in Morris water maze and .nally, the brains were removed and MDA and total thiol concentrations were measured.

Results: The escape latency and swimming path in OVX group were signi.cantly higher than in Sham group (p<0.01). The animals in OVX-LA group had signi.cantly lower swimming path length and escape latency compared to OVX group (p<0.01) while, there was no signi.cant difference between Sham- LA and Sham groups. In OVX-LA group, the brain tissues total thiol concentration was signi.cantly higher, and MDA concentration was lower than of OVX group (p<0.001).There was no signi.cant difference between Sham-LA and Sham groups.

Discussion: It seems that the bene.cial properties of L-Arginine on spatial learning of ovariectomized rats are in part due to its protective capacity against oxidative damage.

Introduction: Several studies have conducted on impairments of executive functions in individuals with methamphetamine addiction; however, only a few have investigated the relationship between executive functions and duration of addiction or abstinence. This study was designed to assess the executive functions in methamphetamine-addicted individuals in relation to the duration of addiction or abstinence.
Methods: A total of 161 subjects aged between 20 and 45 years were categorized into three subgroups: currently abusing (n = 41), abstinent (n = 60), and control healthy individuals (n = 60). A battery of standardized executive function tasks, including Stroop test, Wisconsin Card Sorting test, and Tower of London task, were administered. Data were analyzed using Pearson correlation coefficient, analysis of variance, and post hoc Bonferroni test with SPSS16.0.
Results: Methamphetamine-addicted and abstinent subjects performed worse than the controls. Methamphetamine-abstinent subjects performed better than the currently methamphetamine abusers in most executive functions. Duration of addiction and abstinence were correlated with executive dysfunctions.
Conclusion: This study revealed that although executive functions may be improved by protracted abstinence, executive dysfunctions are not completely relieved, and specific attention to planning and implementation of intervention programs are necessary.

Introduction: This paper proposes a reliable and efficient technique to recognize different epilepsy states, including healthy, interictal, and ictal states, using Electroencephalogram (EEG) signals.
Methods: The proposed approach consists of pre-processing, feature extraction by higher order spectra, feature normalization, feature selection by genetic algorithm and ranking method, and classification by support vector machine with Gaussian and polynomial radial basis function kernels. The proposed approach is validated on a public benchmark dataset to compare it with previous studies.
Results: The results indicate that the combined use of above elements can effectively decipher the cognitive process of epilepsy and seizure recognition. There are several bispectrum and bicoherence peaks at every bi-frequency plane, which reveal the location of the quadratic phase coupling. The proposed approach can reach, in almost all of the experiments, up to 100% performance in terms of sensitivity, specificity, and accuracy.
Conclusion: Comparing between the obtained results and previous approaches approves the effectiveness of the proposed approach for seizure and epilepsy recognition.

Introduction: Acrylamide (ACR) consumption is increasing all over the world. There are some evidence on the literature about its neurotoxic effect on mature animals, but the effects of ACR on postnatal development have been less studied. The purpose of this study was to evaluate the effects of ACR on development of cortical layer, white matter, and number of Purkinje cells of the cerebellum in rat newborns.
Methods: This study was carried out on 20 female Wistar rats (average weight: 180 g, aged: two months). The rats were divided into four groups. Pregnant rats were orally fed with ACR 10 mg/kg and vitamin C 200 mg/kg. In this study, 6 infants of each group (weighting 32-35 g) were randomly selected at day 21 after birth and placed under deep anesthesia and transcardial perfusion. Their cerebellums were fixed and histopathological changes were evaluated with Hematoxylin and Eosin (H&E) staining and cresyl violet method. The volume of cerebellar cortical layers and number of Purkinje cells were investigated by Cavalieri’s principle and physical dissector methods. The obtained data were analyzed by 1-way ANOVA and LSD test using SPSS. P<0.05 considered as statistically significant.
Results: The results showed that newborns of ACR-treated female rats have decreased cerebellar weight (P≤0.05) and lower than average number of Purkinje cells (P≤0.001). ACR also decreased the volume of granular and molecular layer and increased the volume of white matter. While the results showed decreased in white matter volume in vitamin C group (P≤0.001).
Conclusion: ACR induces structural changes in the development of the cerebellar cortical layers in rat newborns, but these changes may be prevented by vitamin C as an antioxidant. 

Introduction: The present study aims to evaluate the Three-Dimensional Diffusion-Weighted reversed fast imaging with steady state free precession (3D DW-PSIF) sequence with respect to imaging of the peripheral nerves; the tibial, medial, and lateral plantar nerves in the lower extremity, ulnar and median nerve in the upper extremity, sciatic nerve, brachial plexus, and lumbosacral plexus, and also to compare its usefulness with the current two-dimensional sequences on a 1.5 T MR scanner.
Methods: A total of 25 healthy subjects underwent MR imaging of peripheral nerves, 5 subjects in each area. In each imaging sequence, including T2W SPAIR and 3D DW-PSIF, images were evaluated for ability to identify the nerves in the related area using a 3-score scale (0-2). Then, by summing up the conspicuity scores, a total certainty score was recorded for each sequence.
Results: With combining the results of all studies, the conspicuity mean (SD) score was 1.57(0.67) on the 3D DW-PSIF images, and 0.74(0.76) on the T2-weighted images (P<0.001). Regarding the lumbosacral plexus, the corresponding certainty mean (SD) scores were 1.80(0.40) and 1.07(0.74) (P<0.001) and with regard to the brachial plexus, they were 1.23(0.83) and 0.75(0.84), (P<0.001). Regarding the ankle/hind foot they were 1.87(0.35) and 0.40(0.50) (P<0.001) and in the wrist/proximal hand, 1.70(0.48) and 0.50(0.52) (P<0.001). Regarding the sciatic nerve, they were 1.80(0.44) and 0.20(0.44) (P=0.003).
Conclusion: 3D DW PSIF provides better manifestation of nerves compared to routine imaging sequences particularly fat saturated T2W images. This novel imaging technique can be used in MR neurography examination protocol for exact localization of the nerve and evaluation of the nerve pathology.

Introduction: Application of biofeedback techniques in rehabilitation has turned into an exciting research area during the recent decade. Providing an appropriate visual or auditory biofeedback signal is the most critical requirement of a biofeedback technique. In this regard, changes in Surface Electromyography (SEMG) signals during wrist movement can be used to generate an indictable visual biofeedback signal for wrist movement rehabilitation via SEMG biofeedback. This paper proposes a novel methodology for selecting the most appropriate features out of wrist muscle SEMG signals. 
Methods: To this end, the surface EMG signals from flexor and extensor muscle groups during wrist joint movements were recorded and analyzed. Some linear and nonlinear features in frequency, time, and time-frequency domains were extracted from the recorded surface EMG signals of the flexor and extensor muscles. Experiments and analyses were performed on ten healthy subjects and four stroke patients with wrist muscle spasticity as the movement disorder subjects. Some heuristic feature selection measures were applied. The main motivation behind choosing applied heuristic feature selection measures was meeting. In the first step, the designed visual biofeedback signal should indicate a healthy wrist motion profile as its successful tracking by the patient guarantees rehabilitation. In addition, the visual biofeedback signal should be a smooth curve thus preventing the patient from discomfort while tracking it on a monitor during the biofeedback therapy. 
Results: In this pilot study, after using the introduced feature selection measures, quantitative and qualitative analyses of the extracted features indicated that Shannon entropy is the most appropriate feature for generating a visual biofeedback signal as a healthy wrist motion profile to improve the ability of stroke patients in controlling wrist joint motion. In addition, it was shown that when the wrist joint moves between a flexed and rest position, the flexor muscle EMG signal should be used for generating a visual biofeedback signal. However when the wrist joint moves between a rest position and an extended position, the extensor muscle EMG signal is appropriate for providing a visual biofeedback signal. It is worth noting that the achieved pilot study results should be confirmed by the future studies with larger samples.
Conclusion: According to the obtained results, it can be concluded that among the analyzed features, the Shannon entropy was the most appropriate feature. It can be employed for generating a visual biofeedback signal for reduction of spasticity in patients with stroke.