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Background and Purpose: The effect of physical activity and living in enriched environment on some cognitive mechanisms in Alzheimer's disease (AD) is not yet well understood. Therefore, this study aimed to investigate the effect of aerobic training along with enriched environment on spatial memory and brainderived neurotrophic factor in the Hippocampal tissue of elderly female Wistar rats with Alzheimer's disease. Materials and Methods: In this experimental study, 30 elderly female Wistar rats with twenty-one-monthold and average weight of 260±20 grams were used and divided into 6 groups: control-healthy, Alzheimer's, sham group, Alzheimer's + aerobic exercise (treadmill), Alzheimer's + enriched environment, Alzheimer's + enriched environment + aerobic exercise (treadmill). Rats in the training groups performed two 15-min sessions with 5-minute passive rest at a speed of 10 m/min in the first and second weeks. In the third week, they performed three sessions at a speed of 15 m/min with a 5-min break, and in the fourth week, four sessions per day at a speed of 15 m/min with a 5-min break. In the enriched environment group, the animals were kept in a plexiglass material larger than the standard cage (60 x 50 x 70 cm³). In these cages, devices such as ladders, hollow pipes, wooden blocks and plastic toys were placed. In Alzheimer's groups, rats were anesthetized by intraperitoneal injection of ketamine (80 mg/kg) and xylazine (20 mg/kg). Then, Alzheimer's Aβ was induced by intracerebroventricular injections (10μg/rat). Spatial memory was measured by Morris water maze, barin derived neurotrophic factor (BDNF) and Trk-B by western blot. In a pilot study in order to evaluate the spatial memory of rats, one week after beta-amyloid injection, all rats were divided into Alzheimer's and control groups. Rats were trained in the maze for four days and the mean percentage permanence in the platform area was recorded. The results of the independent t-test showed that there is a significant difference between the control group and Alzheimer's group (P=0.0152). Therefore, One-way analysis of variance with Tukey's post-hoc test (P<0.05) were used to analyze the data. Results: BDNF increased in all groups significantly (P<0.001), and comparisons between groups were significant except for control vs sham (P=0.27) and Alzheimer's vs Aerobic Alzheimer's (P=0.20) groups. Trk-B increased in all groups and between-group comparisons were significant except for control vs sham (P=0.22), aerobic Alzheimer's vs Alzheimer's enriched environment (P=0.32). However, for spatial memory only between-group comparisons for Alzheimer's vs control (P=0.02), and Alzheimer's vs Alzheimer's + enriched environment + aerobic training (P<0.001) groups were significant. Conclusion: Based on the findings, it can be concluded that aerobic exercise and living in enriched environment can be effective on the spatial memory of elderly Alzheimer's rats through the increase of neurotrophic factors [ABSTRACT FROM AUTHOR]

Postural control is influenced by cognition. In most studies, variability of motor output has been considered regardless of variability in patterns of joint coordination. Uncontrolled manifold framework has been applied to decompose the joint's variance in two components. The first component leaves position of the center of mass in anterior-posterior direction (CoMAP) unchanged (VUCM) while the second component is in charge of variations of CoM (VORT). In this study, 30 healthy young volunteers were recruited. The experimental protocol consisted of three random conditions: quiet standing on a narrow wooden block without a cognitive task (NB), quiet standing on a narrow wooden block with an easy cognitive task (NBE), and quiet standing on a narrow wooden block with a difficult cognitive task (NBD). Results showed that CoMAP sway in NB condition was higher than both NBE and NBD conditions (p =.001). VORT in NB condition was higher than NBE and NBD conditions (p =.003). VORT in NB condition was higher than NBE and NBD conditions (p =.003). VUCM was unchanged in all conditions (p = 1.00) and synergy index in NB condition was smaller than NBE and NBD conditions (p =.006). These results showed that postural synergies increased under dual-task conditions. [ABSTRACT FROM AUTHOR]

Introduction: Mirror neurons have been suggested as a potential neural mechanism of observational learning. This study aims to investigate the effect of self-modeling, skilled model, and learning model on mu rhythm suppression and golf putting acquisition and retention. Methods: The study was conducted on 45 male volunteer students (aged 19.4±0.37 years) in three experimental groups, self-modeling, skilled, and learning models with six sessions of physical and observational training in three periods of pre-test, acquisition, and retention. In the pre-test, after the initial familiarity with the skill, participants performed 10 golf putting actions while scores were recorded. Then, electrical brain waves in C3, C4, and Cz regions were recorded during the observation of 10 golf putting actions by their group-related models. The acquisition period consisted of golf putting training during six sessions, each consisting of six blocks of 10 trials. Before each training block, participants observed golf putting related to their group 10 times in the form of a video. Acquisition and delayed retention tests were also performed by recording scores of 10 golf putting actions, as well as recording electrical brain waves while observing the skill performed by the related model. Results: Mixed analysis of variance (ANOVA) showed that the mu rhythm suppression in the pre-test was more in the self-modeling group compared to the skilled model and learning model groups, but this suppression was not significantly different in all three groups in the acquisition and retention tests. In putting task variables, all three groups that had no significant difference in the pre-test period made considerable progress in learning the desired skill from the pre-test to the acquisition test, and this progress was somewhat stable until the retention test. Also, both in the acquisition and retention periods, the self-modeling group showed better performance than the other two groups; however, no significant difference was observed between these groups. Conclusion: These results suggest that the model-observer similarity is a crucial factor in modeling interventions and can affect the rate of mu rhythm suppression. [ABSTRACT FROM AUTHOR]

The benefits of self-talk on motor performance are well documented. However, there is a gap in the literature on basic research into the mechanisms underlying the performance outcomes of self-talk. The purpose of this study was to determine the neuromuscular mechanisms underlying the effects of instructional and motivational self-talk. Fifteen young females participated in a within-subject counterbalanced design under control, instructional, and motivational self-talk conditions. Surface electromyography (sEMG) was recorded from active (the right biceps and triceps brachii) and passive (the frontalis and left biceps brachii) muscles during reproduction of the elbow flexion angle (90°) in the joint position sense test. The self-talk conditions led to a significantly lower EMG activity of the right biceps muscle, decreased co-contraction ratio of right biceps activity to right triceps activity, and reduced absolute error for the elbow joint position sense compared to the control condition. Also, EMG gradients in the passive muscles were observed in the self-talk conditions but not in the control condition. These findings suggest that attention and motivation are the mechanisms that justify the relationship between self-talk and performance. [ABSTRACT FROM AUTHOR]

Research has shown that large visual illusions and an external focus of attention can improve novice's motor learning. However, the combined effects of these approaches and the underlying mechanisms have yet to be studied. Therefore, the present study examined the effects of a large visual illusion and an external focus on the learning of a dart throwing task in novices and measured the perceptual mechanisms underpinning learning using quiet eye. Forty novice participants were randomly divided into four groups: large visual illusion, external focus of attention, combined large visual illusion and external focus of attention, and control group. The study consisted of a pretest, a practice phase, an immediate retention test, a 24-hr retention test, and a transfer test. Results revealed that all groups increased throwing accuracy and quiet eye duration from pretest to immediate retention. In the immediate retention, 24-hr retention, and transfer test, large visual illusion had greater accuracy and longer quiet eye duration than the control group. In addition, there were no significant differences between the visual illusion and external focus groups for throwing accuracy and quiet eye duration. The findings suggest that combining large visual illusion and external focus can independently improve motor learning but combining these manipulations does not have additive benefits. [ABSTRACT FROM AUTHOR]

Empirical literature addressing the effectiveness of self-talk for expert performers is lacking. We addressed this shortcoming within the existent literature and examined the comparative effects of instructional and motivational self-talk on basketball free throw shooting accuracy and salient movement kinematics. We recruited 20 professional basketball players to participate in a 2 x 2 pre/post-test experiment. Free throw accuracy and movement patterns were recorded, with the latter subsequently used to calculate elbow-wrist coordination variability. Results indicated superior shooting accuracy and reduced movement coordination variability for instructional self-talk compared to baseline conditions, whereas no differences emerged for motivational self-talk. Findings from the study help practitioners to better guide skilled performers how best to use self-talk; an area in urgent need of further research. [ABSTRACT FROM AUTHOR]

Introduction. The aim of the present study was to investigate the effect of unstable resistance training with blood flow restriction (URT with BFR) on short-term memory, strength and dynamic balance in older adults. Material and Methods. A total of 27 male older adults (age= 62 ± 1.5 years) were randomly divided into two experimental groups: URT with BFR, URT without BFR, and a control group. The training program for the experimental groups consisted of bodyweight Scott exercise (three sessions a week for four weeks). The first two weeks included three sets, each set consisted of 15 repetitions at 60-second intervals. The second two weeks included four sets, with each set consisting of 15 repetitions and the use of weight constituting 5% of each person's body weight (mean = 3.5 ± 1.5kg). To restrict blood flow, an 8-cm wide elastic band was used at 72 ± 9 mm Hg arterial pressure. All subjects performed Wechsler memory, 30-sec chair stand test, and timed up and go test (TUG) before and after the intervention. Data analysis was carried out using analysis of covariance (ANCOVA) and Bonferroni post hoc test. Results. The results showed that URT with BFR was significantly superior to other groups in the variables of strength (p = 0.001), dynamic balance (p = 0.0001) and short-term memory (p = 0.04). Conclusions. These findings suggest that URT with BFR can be a useful training method for older adults. [ABSTRACT FROM AUTHOR]

Motor learning is a relatively permanent change in motor performance. Also, one of the factors that can affect movement acquisition and movement patterns is pain and injury. The present study aims to investigate the effect of the induced local and remote pain during dart-throwing skill acquisition by examining motor skill accuracy and coordination variability. Three groups of 30 participants with a mean age of 18–25 were randomly assigned to local and remote pain or control groups. Capsaicin gel was applied to the pain groups for measuring the severity of pain using the Visual Analogue Scale (VAS). The results revealed that pain had no impact on dart-throwing skill acquisition, and there was no significant difference (p = 0.732) among the three groups at three stages of retention test. The results also showed that there was a significant difference among the three groups in terms of variability in shoulder-elbow (p = 0.025) and elbow-wrist joints (p = 0.000) in the deceleration and dart-throwing phases. The Central Nervous System seems to make adjustments when the task is associated with pain during the acquisition phase. Also, the groups with or without pain have notably various strategies, so differently, to perceive motor skills. [ABSTRACT FROM AUTHOR]

Studies on pain are generally conducted for two purposes: first, to study patients with pain who have physical changes due to nerve and muscle lesions, and second, to regain the appropriate kinematic post-pain pattern. The present study aimed to investigate the effect of pain on the coordination variability pattern and throw accuracy. Participants included 30 people with a mean age of 18-25 years who volunteered to participate in the study. Individuals were randomly divided into three groups of local pain, remote pain, and control group. Without pain, participants practiced and acquired skills in 10 blocks of 15 trials. In the retention and transition phase, which were associated with pain, in their respective groups, included 1 hour, 24- hour, and 1- week acquisition; they were re-tested twice in a 15-block trial, which was once with and without pain. The results revealed that pain did not affect the throwing accuracy (p = 0.469). Besides, in the phase of decreasing acceleration in throwing, movement variability pattern in the pain-related groups in the shoulder and elbow joints (p = 0.000), elbow and wrist (p = 0.000), were more than the painless groups. Based on the results, it can be said that the increase in variability in pain-related groups is due to the different strategies and patterns that individuals use to avoid pain. Also, despite the pain, the nervous system attempts to increase the variability find the least painful pattern of movement and reduces this variability over time and using a repetitive pattern. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the effect of landmarks on learning basketball lay-up in beginners. Twenty-seven females (age = 20.30 ± 0.24 years, height = 164.37 ± 0.53 cm) participated in this study. They were assigned to three groups: no landmark group, colored landmark group, and black and white landmark group. All participants performed basketball lay-up for six sessions. The colored group and black and white group trained with the landmarks on the ground while the no landmark group trained without any landmarks based on a trainer instruction. Posttest was performed at the end of the last session of training and also in the retention test following 72 hr. All trials were assessed through 5-point Likert scales, ranging from 1 (very poor) to 5 (very good). The results showed that using landmarks significantly changed the lay-up pattern; however, these changes were not significant for color and lay-up shot accuracy. [ABSTRACT FROM AUTHOR]

The quiet eye is a characteristic of highly skilled perceptual and motor performance that is considered as the final fixation toward a target before movement initiation. The aim of this study was to extend quiet eye–related knowledge by investigating expertise effects on overall quiet eye duration among expert and near-expert basketball players, as well as to determine the relative contribution of early and late visual information in a basketball jump shot by comparing the timing components of quiet eye duration (early and late quite eye). Twenty-seven expert and near-expert male basketball players performed the jump shots. Gaze was recorded with the SensoMotoric Instruments eye tracking glasses and shooting performance accuracy was evaluated by scoring each shot on a scale of 1–8. Six infrared cameras circularly arranged around the participants were used to collect the kinematic information of the players. The performance accuracy, gaze behavior, and kinematic characteristics of the participants during the test were calculated. The experts with longer quiet eye duration had better performance in a basketball jump shot compared to the near-experts. Also the experts had longer early and late quiet eye duration than the near-experts. The results revealed a relationship between quiet eye duration and performance. The combined visual strategy is a more efficient strategy in complex far-aiming tasks such as a basketball jump shot. [ABSTRACT FROM AUTHOR]

Previous studies suggest that visual information is essential for balance and stability of locomotion. We investigated whether visual deprivation is met with active reactions tending to minimize worsening balance and stability during walking in humans. We evaluated effects of vision on kinetic characteristics of walking on a treadmill-ground reaction forces (GRFs) and shifts in the center of mass (COM). Young adults (n = 10) walked on a treadmill at a comfortable speed. We measured three orthogonal components of GRFs and COM shifts during no-vision (NV) and full-vision (FV) conditions. We also computed the dynamic balance index (DN)—the perpendicular distance from the projection of center of mass (pCOM) to the inter-foot line (IFL) normalized to half of the foot length. Locally weighted regression smoothing with alpha-adjusted serial T tests was used to compare GRFs and DN between two conditions during the entire stance phase. Results showed significant differences in GRFs between FV and NV conditions in vertical and ML directions. Variability of peak forces of all three components of GRF increased in NV condition. We also observed significant increase in DN for NV condition in eight out of ten subjects. The pCOM was kept within BOS during walking, in both conditions, suggesting that body stability was actively controlled by adjusting three components of GRFs during NV walking to minimize stability loss and preserve balance. [ABSTRACT FROM AUTHOR]

There were two aims to the present study. First, we sought to investigate how a form of self-controlled practice compared to a well-established strategy of explicitly directing a mover's attention externally when performing the standing long jump. Those two forms of practice were also compared to conditions in which participants were instructed to focus their attention internally or neutrally (i.e., control condition). Second, we investigated if the skill level of the participants was a factor in the comparison of these two forms of training (i.e., directing attention externally and self-controlled practice). In the External condition, volunteers were told to focus on jumping toward a cone that was placed in front of them at a distance of 5-m. In the Internal condition, participants were told to focus on the extension of their knees. In the Self-control condition, volunteers were allowed to choose a distant target to focus their attention on while executing the jump. Participants also completed jumps in a Control condition in which no explicit instructions were provided. Results demonstrated that both skilled and low-skilled participants jumped significantly farther in the External and Self-control conditions compared to jumps completed in the Control and Internal conditions. The findings of this study demonstrate that providing instructions that direct attention externally, or allowing the participant to choose where to direct their attention, resulted in similar enhancements in jumping performance in both low- and high-skilled jumpers. [ABSTRACT FROM AUTHOR]

There were two aims to the present study. First, we sought to investigate how a form of self-controlled practice compared to a well-established strategy of explicitly directing a mover's attention externally when performing the standing long jump. Those two forms of practice were also compared to conditions in which participants were instructed to focus their attention internally or neutrally (i.e., control condition). Second, we investigated if the skill level of the participants was a factor in the comparison of these two forms of training (i.e., directing attention externally and self-controlled practice). In the External condition, volunteers were told to focus on jumping toward a cone that was placed in front of them at a distance of 5-m. In the Internal condition, participants were told to focus on the extension of their knees. In the Self-control condition, volunteers were allowed to choose a distant target to focus their attention on while executing the jump. Participants also completed jumps in a Control condition in which no explicit instructions were provided. Results demonstrated that both skilled and low-skilled participants jumped significantly farther in the External and Self-control conditions compared to jumps completed in the Control and Internal conditions. The findings of this study demonstrate that providing instructions that direct attention externally, or allowing the participant to choose where to direct their attention, resulted in similar enhancements in jumping performance in both low- and high-skilled jumpers. [ABSTRACT FROM AUTHOR]

Implicit skills learning such as riding a bicycle and playing a musical instrument play a central role in daily life. Such skills are learned gradually and are retained throughout life. The learning of motor skill occurs with practice, but skill can also increase between sessions, a process termed "off-line learning". In this research, Participants were tested on an implicit version of the Alternating Serial Reaction Time Task and re-tested 6, 24 or 72 h later. ANOVA revealed significant off-line motor skill improvement participants responding faster at the beginning of Session 2 than at the end of Session 1. The elapsed time between the two sessions influenced the improvement of motor skill improvements as well. Thus, participants' response speed improved more after the 24-, 72hr than after the 6-hr. The subsequent paired-samples t-tests conducted separately for all delay groups revealed that the off-line improvement of motor skill was significant in all groups (p< .05), and in all groups the 6, 24, 72-hr delay led to off-line enhancement (p< .05).This demonstrates that implicitly acquired skills can increase between sessions and the process occurs over hours. These findings are consistent with theoretical accounts of procedural skill learning such as the procedural reinstatement theory as well as with previous studies of retention of other motor skills. [ABSTRACT FROM AUTHOR]