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Introduction: Mental disorders often manifest broad cognitive deficits that detrimentally affect daily functioning. Stress indicated by heart rate variability (HRV) has been linked to these cognitive functions. Objectives: We aimed to develop a new method to assess cognitive performance and simultaneous measurement of psychophysiological signals related to stress and relaxation levels. Methods: 20 adult patients with mental disorders in a rehabilitation program were recruited along with 21 healthy volunteers. A test protocol was carried out with a purpose-developed computerized psychophysiological device. The protocol consisted of a relaxation period; digitized questionnaires on pathological distress (GHQ) and sense of coherence (SOC); gamified cognitive tasks to assess working memory, attention, and decision-making; and a final relaxation period. Acute stress was assessed by heart rate variability measured by a wireless ECG sensor. The inter-beat interval's root mean square of successive differences (RMSSD) was calculated as an inverse stress measure. Relaxation levels were assessed by the relative power of the alpha frequency band measured by a commercial 4-channel EEG headband. Stress and relaxation levels were compared to the first relaxation period as a baseline. Results: Patients scored worse than the reference group both regarding distress (d=7, p=0.004) and sense of coherence (d=-8, p=0.047). The cognitive performance of patients was significantly lower (p<0.001) than the reference group for all tasks. RMSSD at baseline tended to be lower for patients (d=-12.69, p=0.098), reflecting a higher level of physiological stress; 61% of patients started at an elevated stress level compared to 25% of the reference group. In addition, relative alpha levels at baseline were also lower (d=-5.8%, p=0.007) for patients. Compared to baseline, RMSSD decreased on average to 94% during cognitive assessments in patients and decreased to 91% by the end of the final relaxation. RMSSD decreased to 76% in the reference group and reached a final value of 78% of the baseline. Alpha levels slightly increased among patients during the tasks (103.4%) and then returned close to baseline (99.1%). For the reference group, alpha decreased during the tasks (95.5%) and then slightly increased (97.3%). Conclusions: Patients displayed heightened distress, reduced sense of coherence, and inferior cognitive scores compared to controls. While starting with higher stress, patients exhibited less elevation in stress during tasks, coupled with alterations in alpha levels, suggesting diminished engagement or focus. Our innovative method could aid in the diagnostics of cognitive performance in mental patients after further measurements for validation. Disclosure of Interest: None Declared [ABSTRACT FROM AUTHOR]

Vision plays a fundamental role in the control of human locomotion, including walking gait. Given that side-dominance is associated with differences in motor control, the present study aimed to determine if patches obscuring half of the visual field affect left- and right-side dominant individuals' gait kinematics and accompanying leg muscle activation differently. Healthy right- (n = 15, age = 28.2 ± 5.5 years) and left-side (n = 9, age = 27.9 ± 5.8 years) dominant participants performed 10 min of walking trials on a treadmill at a self-selected speed with 5 min of rest between three randomized trials, i.e., wearing clear glasses or glasses with left-or right half-field eye patching. In addition to a set of spatiotemporal and kinematic gait parameters, the average activity during the separated gait cycle phases, and the start and end of muscle activation in % of the gait cycle were calculated from five muscles in three muscle groups. Our results indicate that gait kinematics of left- and right-side dominant participants were similar both in their dominant and non-dominant legs, regardless of half-field eye patching condition. On the other hand, inter-group differences were found in selected kinematic variables. For instance, in addition to larger but less variable step width, our results suggest larger ankle and knee ROM in right- vs. left-sided participants. Furthermore, medial gastrocnemius and biceps femoris muscle activation showed selected differences at certain phases of the gait cycle between participants' dominant and non-dominant legs. However, it was also unaffected by the half-field eye patching condition. Moreover, the endpoint of medial gastrocnemius activation was affected by side-dominance, i.e., its activation ended earlier in the non-dominant leg of right- as compared to left-side dominant participants. Our results suggest no major differences in walking gait kinematics and accompanying muscle activation between half-field eye patching conditions in healthy adults; nevertheless, side-dominance may affect biomechanical and neuromuscular control strategies during walking gait., Competing Interests: Declarations. Competing interests: The authors declare no competing interests. Conflict of interest: All authors declare that they do not have any conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results. Word count: 5689 words., (© 2025. The Author(s).)

We used a data-driven approach to study the electrophysiological correlates of the working memory subprocesses revealed by the reference-back paradigm. In the absence of prior research, we focused on how aging affects the four subprocesses: updating, substitution, gate opening, and gate closing. We conducted our experiment with 24 younger adults (M = 20.17±1.47) and 23 older adults (M = 67.35±4.01). Significant reaction time costs were observed for all four subprocesses, but age-related differences were found only in substitution, which was larger in older than younger adults, indicating it as being the most vulnerable subprocess in aging. Using difference waves, we identified event-related potential components that characterize the subprocesses we studied. Regarding updating: three occipital negativities between 80-180 ms, 300-400 ms, and 400-1,000 ms were observed, with only the latter range showing age group differences. Source analysis showed larger activity differences in the right frontal and temporal areas for younger adults. Regarding substitution: a frontal positivity between 250-600 ms emerged in younger adults, while a posterior positivity between 550-750 ms was found in older adults indicating different underlying processes supported by sLORETA results. Regarding gate opening: three parieto-occipital components were identified: a negativity between 150-250 ms, a positivity between 300-500 ms, and a positivity between 500-700 ms, all showing age-related differences. Regarding gate closing: we found an occipital negativity between 150-300 ms and a frontal positivity between 300-600 ms, neither of which changed between the age groups. From our findings, we conclude that the process of protecting information (gate closing) remains stable with age, despite older adults' sensitivity to interference. Conversely, we observed age-related differences in gate opening, which may have led to different strategies being used by the two age groups during substitution (the process by which new information is incorporated into working memory), as reflected in the distinct brain activity patterns observed., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Gaál et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: The prone plank test has been often used to assess the strength and endurance of trunk muscles. We aimed to develop a new measurement protocol to objectively monitor the changes in spinal curves and muscle activity simultaneously., Methods: Eleven adolescent male basketball athletes (13-17 years) performed a one-minute plank test. Spinal curvatures (thoracic kyphosis (TK) and lumbar lordosis (LL)) were determined at each time point by optical tracking of markers placed on the spinous processes of 10 vertebrae. Eleven muscles were measured by surface electromyography to determine muscle fatigue via changes in median frequency., Results: TK significantly increased (p = 0.003) from the first to the last 10 s of the plank test; changes in LL were mixed within the group. Only the rectus abdominis showed consistent and significant fatigue (p < 0.001). The increased spinal curves significantly correlated with the fatigue of biceps femoris (TK: r = -0.75, p = 0.012; LL: r = -0.71, p = 0.019) indicating a compensatory muscle activation and spinal curve changes in response to fatigue., Conclusion: Our protocol may support future researches that aim to objectively evaluate the prone plank test and which posture-related muscles need strengthening for the individual., (© 2023. The Author(s).)

We examined the effects of side-dominance on the laterality of standing stability using ground reaction force, motion capture ( MoCap ), and EMG data in healthy young adults. We recruited participants with strong right ( n = 15) and left ( n = 9) hand and leg dominance (side-dominance). They stood on one or two legs on a pair of synchronized force platforms for 50 s with 60 s rest between three randomized stance trials. In addition to 23 CoP -related variables, we also computed six MoCap variables representing each lower-limb joint motion time series. Moreover, 39 time- and frequency-domain features of EMG data from five muscles in three muscle groups were analyzed. Data from the multitude of biosignals converged and revealed concordant patterns: no differences occurred between left- and right-side dominant participants in kinetic, kinematic, or EMG outcomes during bipedal stance. Regarding single leg stance, larger knee but lower ankle joint kinematic values appeared in left vs right-sided participants during non-dominant stance. Left-vs right-sided participants also had lower medial gastrocnemius EMG activation during non-dominant stance. While right-side dominant participants always produced larger values for kinematic data of ankle joint and medial gastrocnemius EMG activation during non-dominant vs dominant unilateral stance, this pattern was the opposite for left-sided participants, showing larger values when standing on their dominant vs non-dominant leg, i.e., participants had a more stable balance when standing on their right leg. Our results suggest that side-dominance affects biomechanical and neuromuscular control strategies during unilateral standing., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Négyesi, Petró, Salman, Khandoker, Katona, Wang, Almaazmi, Hortobágyi, Váczi, Rácz, Pálya, Grand, Kiss and Nagatomi.)

Dynamic balancing abilities can be assessed with perturbation tests. The present study examined the effectiveness of balancing (damping ratio) and the recovery action (directional ratio) in bipedal and dominant single-leg stance in the young population. Twenty-four healthy young adult participants completed unidirectional lateral perturbations successfully using a Posturomed© platform (Haider Bioswing, Germany). Single-leg stances had similar damping scores ( p  = 0.551) to and lower directional ratio values ( p  = 0.002) than bipedal recoveries. This shows that different recovery actions can achieve similar effectiveness in the two stances. A test evaluation methodology that simultaneously utilises performance and motion characteristic parameters was demonstrated.

Background: Static balancing assessment is often complemented with dynamic balancing tasks. Numerous dynamic balancing assessment methods have been developed in recent decades with their corresponding balancing devices and tasks., Objective: The aim of this systematic literature review is to identify and categorize existing objective methods of standing dynamic balancing ability assessment with an emphasis on the balancing devices and tasks being used., Data Sources: Three major scientific literature databases (Science Direct, Web of Science, PLoS ONE) and additional sources were used., Study Selection: Studies had to use a dynamic balancing device and a task described in detail. Evaluation had to be based on objectively measureable parameters. Functional tests without instrumentation evaluated exclusively by a clinician were excluded. A total of 63 articles were included., Data Extraction: The data extracted during full-text assessment were: author and date; the balancing device with the balancing task and the measured parameters; the health conditions, size, age and sex of participant groups; and follow-up measurements., Data Synthesis: A variety of dynamic balancing assessment devices were identified and categorized as 1) Solid ground, 2) Balance board, 3) Rotating platform, 4) Horizontal translational platform, 5) Treadmill, 6) Computerized Dynamic Posturography, and 7) Other devices. The group discrimination ability of the methods was explored and the conclusions of the studies were briefly summarized., Limitations: Due to the wide scope of this search, it provides an overview of balancing devices and do not represent the state-of-the-art of any single method., Conclusions: The identified dynamic balancing assessment methods are offered as a catalogue of candidate methods to complement static assessments used in studies involving postural control.