Digital Museum of Retinal Ganglion Cells with Dense Anatomy and Physiology.

When 3D electron microscopy and calcium imaging are used to investigate the structure and function of neural circuits, the resulting datasets pose new challenges of visualization and interpretation. Here, we present a new kind of digital resource that encompasses almost 400 ganglion cells from a single patch of mouse retina. An online "museum" provides a 3D interactive view of each cell's anatomy, as well as graphs of its visual responses. The resource reveals two aspects of the retina's inner plexiform layer: an arbor segregation principle governing structure along the light axis and a density conservation principle governing structure in the tangential plane. Structure is related to visual function; ganglion cells with arbors near the layer of ganglion cell somas are more sustained in their visual responses on average. Our methods are potentially applicable to dense maps of neuronal anatomy and physiology in other parts of the nervous system.

Synapses from the Motor Cortex and a High-Order Thalamic Nucleus are Spatially Clustered in Proximity to Each Other in the Distal Tuft Dendrites of Mouse Somatosensory Cortex.

The posterior medial nucleus of the thalamus (POm) and vibrissal primary motor cortex (vM1) convey essential information to the barrel cortex (S1BF) regarding whisker position and movement. Therefore, understanding the relative spatial relationship of these two inputs is a critical prerequisite for acquiring insights into how S1BF synthesizes information to interpret the location of an object. Using array tomography, we identified the locations of synapses from vM1 and POm on distal tuft dendrites of L5 pyramidal neurons where the two inputs are combined. Synapses from vM1 and POm did not show a significant branchlet preference and impinged on the same set of dendritic branchlets. Within dendritic branches, on the other hand, the two inputs formed robust spatial clusters of their own type. Furthermore, we also observed POm clusters in proximity to vM1 clusters. This work constitutes the first detailed description of the relative distribution of synapses from POm and vM1, which is crucial to elucidate the synaptic integration of whisker-based sensory information.

Space-time wiring specificity supports direction selectivity in the retina.

How does the mammalian retina detect motion? This classic problem in visual neuroscience has remained unsolved for 50 years. In search of clues, here we reconstruct Off-type starburst amacrine cells (SACs) and bipolar cells (BCs) in serial electron microscopic images with help from EyeWire, an online community of 'citizen neuroscientists'. On the basis of quantitative analyses of contact area and branch depth in the retina, we find evidence that one BC type prefers to wire with a SAC dendrite near the SAC soma, whereas another BC type prefers to wire far from the soma. The near type is known to lag the far type in time of visual response. A mathematical model shows how such 'space-time wiring specificity' could endow SAC dendrites with receptive fields that are oriented in space-time and therefore respond selectively to stimuli that move in the outward direction from the soma.

The effects of symmetric center of pressure displacement training with feedback on the gait of stroke patients.

[Purpose] This study investigated the effects of COP displacement training using visual feedback had on the gait of patients with hemiplegia due to stroke. [Subjects and Methods] This study was conducted with 20 patients with hemiplegia due to stroke. The training consisted of five training sets repeated 10 times and the activity was conducted for 15 minutes each session, three times per week for six weeks immediately after completion of central nervous system developmental treatment. [Results] A comparison of the results of before and after the experiment found that the COP displacement training group showed significant improvements in step length, stride length, gait velocity, and the functional reach test, while the control group showed significant improvement only in the functional reach test. In the intergroup comparison, the COP displacement training group showed significant improvements in paretic side step length, paretic side stride length, gait velocity, and the functional reach test compared to the control group. [Conclusion] In conclusion, according to the results of this study, visual feedback training for COP displacement is more effective at enhancing the gait and balance of hemiplegic patients due to stroke than only performing feedback training for even weight distribution.

The relationship between smartphone use and subjective musculoskeletal symptoms and university students.

[Purpose] The purpose of this study was to investigate the use of smartphones by university students in selected areas, their musculoskeletal symptoms, and the associated hazard ratio. [Subjects and Methods] This involved the completion of a self-administered questionnaire by dental hygiene students in Seoul, Gyeonggido, and Gyeongsangbukdo. The 292 completed copies of the questionnaire were then analyzed. [Results] The most painful body regions after the use of smartphones were found to be the shoulders and neck. In the musculoskeletal system, back pain was found to have a positive correlation with the size of the smartphone's liquid crystal display (LCD) screen, and pain in legs and feet were found to have a negative correlation with the length of time that the smartphone was used. As a result, it was revealed that the use of a smartphone was correlated with musculoskeletal symptoms. [Conclusion] Therefore, in today's environment, where the use of smartphones is on the rise, it is necessary to improve the ways that they are used and to develop a preventive program to alleviate the symptoms of musculoskeletal damage.

The effects of respiratory muscle strengthening exercise using a sling on the amount of respiration.

[Purpose] The purpose of this study was to present aerobic exercise that can be performed together with respiratory muscle strength training and examine whether the vital capacity of individuals can be enhanced when respiratory muscle strength training is conducted together with aerobic exercise. [Subjects and Methods] The subjects were 10 male students and 8 female students. The sling exercise method was used to conduct three types of training to strengthen the muscles around the shoulder joints. A maximal respiratory quotient measurement device was used to measure the vital capacity of the subjects five times. [Results] There was a significant difference in each respiratory training time point compared with before the performance of respiratory training. [Conclusion] This study presented respiratory muscle strength training using a sling as a training method for respiratory training.

Effects of high-frequency current therapy on abdominal obesity in young women: a randomized controlled trial.

[Purpose] The aim of this study was to determine the effects of high-frequency current therapy on the abdominal obesity levels of young women. [Subjects] Twenty-two women with abdominal obesity were randomly allocated to either an experimental group (n 1 = 10) or a control group (n 2 = 12). [Methods] The experimental group subjects received high-frequency current therapy for the abdominal region 3 times per week for 6 weeks (a total of 18 sessions). Outcome measures were waist circumference, body mass index, and body composition data (abdominal obesity rate, subcutaneous fat mass, and body fat percentage). [Results] Significant main effects of time in the waist circumference, abdominal obesity rate, subcutaneous fat mass, and body fat percentage were found. Significant time-by-group interactions were found for waist circumference, abdominal obesity rate, subcutaneous fat mass, and body fat percentage. [Conclusion] The use of the high-frequency current therapy may be beneficial for reducing the levels of abdominal obesity in young women.

Effects of fast and slow squat exercises on the muscle activity of the paretic lower extremity in patients with chronic stroke.

[Purpose] The purpose of this study was to investigate the effects of the speed of squat exercises on paretic lower extremity muscle activity in patients with hemiplegia following a stroke. [Subjects and Methods] Ten stroke patients performed fast and slow squat exercises for 2 seconds and 8 seconds, respectively. The muscle activities of the paretic and non-paretic sides of the rectus femoris muscle, the biceps femoris muscle, and the tibialis anterior muscle were assessed and compared using surface electromyography. [Results] The paretic side of the rectus femoris muscle showed statistically significant differences in the fast squat exercise group, which demonstrated the highest muscle activity during the rapid return to the upright position. [Conclusion] The rectus femoris muscle showed the highest muscle activity during the return to the upright position during the fast squat exercise, which indicates that the rectus femoris muscle is highly active during the fast squat exercise.

A study of abdominal ultrasound therapy combined with complex exercise for effective obesity management among shift work employees.

[Purpose] This study aimed to examine the effects of abdominal ultrasound accompanied by complex exercise in shift work employees working in industry. [Subjects and Methods] Thirty shift work employees were randomly assigned to either a complex exercise group (control group) or a complex exercise and ultrasound treatment group (experimental group). The control group carried out complex exercise five times per week for 4 weeks, while the experimental group performed complex exercise twice per week and received deep ultrasound three times per week for 4 weeks. [Results] The results showed that there were no significant differences in body composition between the two groups. There were significant changes in weight, lean body mass, body fat mass, and body mass index in the control group; meanwhile, significant changes in weight and body fat mass were observed in the experimental group. There were no significant differences in blood lipids between the two groups. There was a significant decrease in high-density lipoprotein cholesterol (HDL-C) in the control group; furthermore, a significant decrease in total cholesterol was observed in the experimental group, along with significant increases in HDL-C and low-density lipoprotein cholesterol. [Conclusion] According to the results of this study concerning short-term obesity management programs, complex exercise was effective for improving of body composition and weight loss, while complex exercise combined with abdominal ultrasound had a good effect on blood lipids and secondary complication prevention.

Effects of visibility and types of the ground surface on the muscle activities of the vastus medialis oblique and vastus lateralis.

[Purpose] The purpose of this study was to compare the effects of visibility and types of ground surface (stable and unstable) during the performance of squats on the muscle activities of the vastus medialis oblique (VMO) and vastus lateralis (VL). [Subjects and Methods] The subjects were 25 healthy adults in their 20s. They performed squats under four conditions: stable ground surface (SGS) with vision-allowed; unstable ground surface (UGS) with vision-allowed; SGS with vision-blocked; and UGS with vision-blocked. The different conditions were performed on different days. Surface electromyogram (EMG) values were recorded. [Results] The most significant difference in the activity of the VMO and VL was observed when the subjects performed squats on the UGS, with their vision blocked. [Conclusion] For the selective activation of the VMO, performing squats on an UGS was effective, and it was more effective when subjects' vision was blocked.

The effects of stair gait exercise on static balance ability of stroke patients.

[Purpose] This study examined the effects of stair gait exercise on the static balance ability of chronic stroke patients. [Subjects and Methods] The thirty stroke patients who participated in this experiment were randomly assigned to an experimental (n=15) or control (n=15) group. The experimental group performed stair gait exercise for 30 minutes, while the control group performed flat surface gait exercise for 30 minutes. The programs lasted four weeks, with both groups performing the exercises three times per week for 30 minutes each time. The stability balance ability of subjects was measured and compared before and after the interventions. [Results] The results of the experimental group showed a significantly different values, but those of the control group did not. Between-group comparison of changes in the anterior/posterior length in the limit of stability revealed significant increases in the experimental group but no significant increase in the control group. Only the surface area ellipse of Romberg, the length of Romberg, and length/area of Romberg showed significant differences between the two groups after the interventions. [Conclusion] The static balance ability improved in the group that performed the stair gait exercise. This study provides important data for identifying the recovery of balance ability through rehabilitation exercises in patients with nervous system diseases.

Effects of Low-frequency Current Sacral Dermatome Stimulation on Idiopathic Slow Transit Constipation.

[Purpose] This study aimed to determine whether low-frequency current therapy can be used to reduce the symptoms of idiopathic slow transit constipation (ISTC). [Subjects] Fifteen patients (ten male and five female) with idiopathic slow transit constipation were enrolled in the present study. [Results] Bowel movements per day, bowel movements per week, and constipation assessment scale scores significantly improved after low-frequency current simulation of S2-S3. [Conclusion] Our results show that stimulation with low-frequency current of the sacral dermatomes may offer therapeutic benefits for a subject of patients with ISTC.

Comparative connectomics of dauer reveals developmental plasticity.

A fundamental question in neurodevelopmental biology is how flexibly the nervous system changes during development. To address this, we reconstructed the chemical connectome of dauer, an alternative developmental stage of nematodes with distinct behavioral characteristics, by volumetric reconstruction and automated synapse detection using deep learning. With the basic architecture of the nervous system preserved, structural changes in neurons, large or small, were closely associated with connectivity changes, which in turn evoked dauer-specific behaviors such as nictation. Graph theoretical analyses revealed significant dauer-specific rewiring of sensory neuron connectivity and increased clustering within motor neurons in the dauer connectome. We suggest that the nervous system in the nematode has evolved to respond to harsh environments by developing a quantitatively and qualitatively differentiated connectome.

Comparison of Two-point Discrimination Perception in Stroke Patients with and without Diabetes Mellitus.

[Purpose] The aim of this study was to compare two-point discrimination (TPD) perception in stroke patients with diabetes mellitus (DM) and without diabetes mellitus (non-DM). [Subjects] The subjects were 53 poststroke hemiparetic patients (21 stroke patients with DM; 32 stroke patients without DM). [Methods] TPD was measured on the tips of the first through fifth fingers on both the affected and unaffected sides. [Result] Comparison of TPD between fingers on the unaffected side and affected side fingers showed significantly poorer responses in all five fingers on the affected side. TPD was also significantly poorer in the DM group compared with the non-DM group in all five fingers on the affected side, but no differences were observed for the unaffected side. [Conclusion] These findings suggest that TPD was significantly poorer in the fingers on the affected side vs. the unaffected side in poststroke hemiparetic patients. DM caused a significantly poorer TPD in the fingers on the affected side in poststroke patients but had no significant effect on the fingers on the unaffected side.

Caenorhabditis elegans Connectomes of both Sexes as Image Classifiers.

Connectome, the complete wiring diagram of the nervous system of an organism, is the biological substrate of the mind. While biological neural networks are crucial to the understanding of neural computation mechanisms, recent artificial neural networks (ANNs) have been developed independently from the study of real neural networks. Computational scientists are searching for various ANN architectures to improve machine learning since the architectures are associated with the accuracy of ANNs. A recent study used the hermaphrodite Caenorhabditis elegans (C. elegans) connectome for image classification tasks, where the edge directions were changed to construct a directed acyclic graph (DAG). In this study, we used the whole-animal connectomes of C. elegans hermaphrodite and male to construct a DAG that preserves the chief information flow in the connectomes and trained them for image classification of MNIST and fashion-MNIST datasets. The connectome-inspired neural networks exhibited over 99.5% and 92.6% of accuracy for MNIST and fashion-MNIST datasets, respectively, which increased from the previous study. Together, we conclude that realistic biological neural networks provide the basis of a plausible ANN architecture. This study suggests that biological networks can provide new inspiration to improve artificial intelligences (AIs).

Influence of the Hawthorne effect on spatiotemporal parameters, kinematics, ground reaction force, and the symmetry of the dominant and nondominant lower limbs during gait.

The Hawthorne effect is a change in behavior resulting from awareness of being observed or evaluated. This study aimed to determine whether awareness of being evaluated or presence of an observer influence gait. Twenty-one young women were asked to walk in three conditions. In the first condition (unawareness of evaluation; UE), participants were aware that it was a practice trial, and there was no observer. In the second condition (awareness of evaluation; AE), participants were aware that their gait was being evaluated. The third condition (AE + researcher observation; RO) was similar to the second condition except that an additional researcher observed the participant' gait. The spatiotemporal, kinematic, ground reaction forces, and ratio index (symmetry of both lower limbs) were compared among the three conditions. A higher ratio index indicated a relative increase in the value on left versus right. Gait speed (P = 0.012) and stride length (right and left; P = 0.006 and 0.007, respectively) were significantly increased in the AE + RO than in UE. Range of motion of the right hip and left ankle was significantly greater in AE than in UE (P = 0.039 and 0.012, respectively). The ratio index of ground reaction force during push-off was significantly higher in AE and AE + RO conditions than in UE (P < 0.001 and P = 0.004, respectively). The Hawthorne effect (awareness of being evaluated or presence of an observer) potentially influences gait. Thus, factors that influence gait analysis should be considered when evaluating normal gait.

Comparing the Impact of Upper Body Control and Core Muscle Stabilization Training on Landing Biomechanics in Individuals with Functional Ankle Instability: A Randomized Controlled Trial.

Functional ankle instability (FAI), which is characterized by recurrent ankle sprains and perceived joint instability, arises from various factors contributing to compromised biomechanical control during activities, particularly those involving landing tasks. While current research predominantly addresses lower-extremity and core stabilization interventions for FAI, the contribution of upper body control to landing biomechanics in this population remains insufficiently explored. In this study, 42 participants (19 males, 23 females) with FAI were randomly assigned to either the upper-body control training group (UBCTG) or the core muscle stabilization training group (CMSTG). The groups underwent six-week interventions, with the UBCTG receiving a dynamic core exercise program including upper body control and the CMSTG receiving static core muscle training. Pre- and post-intervention assessments encompassed electromyography of the gastrocnemius, tibialis anterior, and peroneus longus, motion analysis of the lower extremities, and ground reaction force (GRF) readings during a single-leg-jump task. Additionally, dynamic balance was assessed using the Y balance test and self-reported measurements of ankle instability were performed. The results showed similar increases in muscle activation, joint movement, and self-reported ankle instability scores within both groups. However, significant between-group differences were observed in terms of knee flexion angle, dynamic balance, and ankle instability scores, favoring the UBCTG. Although the peak vertical GRF significantly decreased and the time to peak vertical GRF increased in both groups, more changes were noted in the UBCTG. Our results demonstrated that dynamic core exercises with additional upper body control training enhance landing biomechanics, dynamic balance, and stability in individuals with FAI. Consequently, we recommend incorporating shoulder girdle exercises, proprioceptive drills, and balance exercises into dynamic core training.

A leaky integrate-and-fire computational model based on the connectome of the entire adult Drosophila brain reveals insights into sensorimotor processing.

The forthcoming assembly of the adult Drosophila melanogaster central brain connectome, containing over 125,000 neurons and 50 million synaptic connections, provides a template for examining sensory processing throughout the brain. Here, we create a leaky integrate-and-fire computational model of the entire Drosophila brain, based on neural connectivity and neurotransmitter identity, to study circuit properties of feeding and grooming behaviors. We show that activation of sugar-sensing or water-sensing gustatory neurons in the computational model accurately predicts neurons that respond to tastes and are required for feeding initiation. Computational activation of neurons in the feeding region of the Drosophila brain predicts those that elicit motor neuron firing, a testable hypothesis that we validate by optogenetic activation and behavioral studies. Moreover, computational activation of different classes of gustatory neurons makes accurate predictions of how multiple taste modalities interact, providing circuit-level insight into aversive and appetitive taste processing. Our computational model predicts that the sugar and water pathways form a partially shared appetitive feeding initiation pathway, which our calcium imaging and behavioral experiments confirm. Additionally, we applied this model to mechanosensory circuits and found that computational activation of mechanosensory neurons predicts activation of a small set of neurons comprising the antennal grooming circuit that do not overlap with gustatory circuits, and accurately describes the circuit response upon activation of different mechanosensory subtypes. Our results demonstrate that modeling brain circuits purely from connectivity and predicted neurotransmitter identity generates experimentally testable hypotheses and can accurately describe complete sensorimotor transformations.

The Effect of Augmented Reality-Based Proprioceptive Training Program on Balance, Positioning Sensation and Flexibility in Healthy Young Adults: A Randomized Controlled Trial.

This study investigates whether Augmented Reality (AR)-based interventions can be as effective as physical therapists (PT) regarding balance, positioning sensation, and flexibility. A sample of 39 regular people who voluntarily participated in this study were randomly distributed into two groups. Then AR was applied in the experimental group and PT was applied in the control group. Variables were measured by Tetrax (static balance), Y-balance test (dynamic balance), CSMI (proprioception), and sit and reach test (flexibility). All measurements were analyzed using paired t-test and independent t-test. The exercise program of this study improved the stability index (ST) of the static balance in both groups after the intervention, and there was a significant difference (p < 0.05) at normal eye close (NC) and Pillow with eye close (PC) positions. Moreover, regarding the case of dynamic balance, there were significant differences in AR and PT groups to reach in all directions (p < 0.05). In the case of positioning sensation, there was no significant difference in both groups (p > 0.05), and there was a significant difference in flexibility (p < 0.05). When comparing the two groups, there was no significant difference in all categories (p > 0.05). As a result, AR can be considered an effective form of therapy and can be selected according to individual conditions.

Automated Synapse Detection Method for Cerebellar Connectomics.

The connectomic analyses of large-scale volumetric electron microscope (EM) images enable the discovery of hidden neural connectivity. While the technologies for neuronal reconstruction of EM images are under rapid progress, the technologies for synapse detection are lagging behind. Here, we propose a method that automatically detects the synapses in the 3D EM images, specifically for the mouse cerebellar molecular layer (CML). The method aims to accurately detect the synapses between the reconstructed neuronal fragments whose types can be identified. It extracts the contacts between the reconstructed neuronal fragments and classifies them as synaptic or non-synaptic with the help of type information and two deep learning artificial intelligences (AIs). The method can also assign the pre- and postsynaptic sides of a synapse and determine excitatory and inhibitory synapse types. The accuracy of this method is estimated to be 0.955 in F1-score for a test volume of CML containing 508 synapses. To demonstrate the usability, we measured the size and number of the synapses in the volume and investigated the subcellular connectivity between the CML neuronal fragments. The basic idea of the method to exploit tissue-specific properties can be extended to other brain regions.