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Freezing is one of the most extensively studied defensive behaviors in rodents. Both reduced body and gaze movements during anticipation of threat also occur in humans and have been discussed as translational indicators of freezing but their relationship remains unclear. We thus set out to elucidate body and eye movements and concomitant autonomic dynamics in anticipation of avoidable threat. Specifically, 50 participants viewed naturalistic pictures that were preceded by a colored fixation cross, signaling them whether to expect an inevitable (shock), no (safety), or a potential shock (flight) that could be avoided by a quick button press. Body sway, eye movements, the heart rate and skin conductance were recorded. We replicated previously described reductions in body sway, gaze dispersion, and the heart rate, and a skin conductance increase in flight trials. Stronger reductions in gaze but not in body sway predicted faster motor reactions on a trial‐wise basis, highlighting their functional role in action preparation. We failed to find a trait‐like relationship between body and gaze movements across participants, but their temporal profiles were positively related within individuals, suggesting that both metrics partly reflect the same construct. However, future research is desirable to assess these response patterns in naturalistic environments. A more ethological examination of different movement dynamics upon threat would not only warrant better comparability between rodent and human research but also help determine whether and how eye‐tracking could be implemented as a proxy for fear‐related movements in restricted brain imaging environments. Our article unravels the relationship between body and eye movements in human threat anticipation, drawing parallels with freezing behavior in rodents. We reveal a physio‐behavioral defensive state, emphasize eye‐tracking's potential in neuroimaging, and spotlight the need for improved translational research practices across species. [ABSTRACT FROM AUTHOR]

The ability to coordinate with others is fundamental for humans to achieve shared goals. Often, harmonious interpersonal coordination requires learning, such as ensemble musicians rehearing together to synchronize their low‐level timing and high‐level aesthetic musical expressions. We investigated how the coordination dynamics of a professional string quartet changed as they learned unfamiliar pieces together across eight trials. During all trials, we recorded each musician's body sway motion data, and quantified the group's body sway similarity (cross‐correlation) and information flow (Granger causality) on each trial. In line with our hypothesis, group similarity increased, while group information flow decreased significantly across trials. In addition, there was a trend such that group similarity, but not information flow, was related to the quality of the performances. As the ensemble converged on a joint interpretation through rehearsing, their body sways reflected the change from interpersonal information flow for coordinative mutual adaptations and corrections, to synchronous musical coordination made possible by the musicians learning a common internally based expressive interpretation. [ABSTRACT FROM AUTHOR]

This study examined the effects of static magnetic exposure on body sway during a static posture. The subjects were located 80 cm away from the magnetic resonance imaging (MRI) scanner, and their motions were captured by a motion‐capture system. The average exposure level was 65 ± 8 mT (n = 15) at the head position. The results were compared with those from control conditions acquired at the console room. Small increments in the total sway paths and the anterior/posterior sway paths were detected through magnetic field exposure condition. However, the overall effect was small because the actual changes in parameter values were very small. © 2022 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

In accordance with developments in the image technology over recent years, it has become easier towatch 3Dvideo clips. As the viewing of 3D video has become more commonplace, symptoms such as visually induced motion sickness (VIMS) and eye fatigue have been reported. Although various theories regarding the underlying causes of the VIMS have been proposed, these causes have yet to be fully investigated. In a previous study, the background of an image was shown to influence the equilibrium function of a subject viewing a 3D video clip. In this study, the authors investigated the influence of image elements such as the size of the visual field especially in the backgrounds of the projected image and velocity of the visual target speed on the body of a subject viewing a 3D video clips by measuring their body sway, the electrocardiogramsignals, and the cerebral blood flow using functional near-infrared spectroscopy (fNIRS). Our results has indicated that the value of the total locus length is significantly higher while viewing a video clip whose visual fields of backgrounds is not narrowed than that with narrower backgrounds. This suggests that stability in the system to control their posture can be enhanced by reducing the amount of visual information. [ABSTRACT FROM AUTHOR]

Archery is a sport that requires fine movement control, and postural stability is considered an important variable to achieve high performance. In order to better understand the coupling between archer and bow during the aiming phase, the aim of this study was to investigate the relationship between bow stability and postural control in recurve archery according to shooting performance. A total of 8 archers shot 6 arrows at a 13-m distant target. The three-dimensional position of one marker attached to the bow and the center of pressure (COP) position of the archer (the point of application of the resultant ground reaction force on a force plate) were measured during the aiming phase, representing bow and archer displacement, respectively. COP displacement in the direction across the target (COPY), length of the COP trajectory (DCOP) and length of the bow trajectory (Dbow) were higher in the lowest scoring shot compared to the highest one. A strong and significant correlation was found between COP and bow displacement in the direction towards/away from the target (COPX and DX) and between COPX and vertical displacement of the bow (DZ) during the highest scoring shot. This result indicates that synchronization between body and bow sway may influence the accuracy of the shot, suggesting that combined balance and bow stability training exercises would be beneficial to improve archery performance. [ABSTRACT FROM AUTHOR]

Wearing dentures has been believed to decrease the instability of the postural sway using the total length of centre of pressure (CoP) trajectory or the magnitude of its variability. However, the physical aspects of the postural sway have not been taken into account while evaluating the CoP in patients who wear dentures. The CoP fluctuations are found to show a random walk process. Therefore, changes in the random movement of CoP caused by wearing dentures should be examined by nonlinear dynamics that enables analysis of the characteristics found in the random movement. We evaluated the effect of complete denture installation on CoP sway for twenty-six edentulous patients by performing the following steps. First, we excluded subjects who did not show crossover in spectral analyses. Then, we evaluated the spectral characteristics and phase shifts of the velocities of CoP sway for the subjects who showed crossover. We found that wearing complete dentures decreased the fluctuations in the high-frequency part of the power spectral density ( PSD) and the phase shift in the mediolateral direction. On the other hand, we also found that the use of complete dentures decreased the fluctuations of PSD amplitude in the anteroposterior direction. From the point of view of the kinetic energy of the musculoskeletal system, we suggested that the use of complete dentures could reduce the energy consumption for the standing posture. [ABSTRACT FROM AUTHOR]

This study investigates the primary factors responsible for cognitive performance improvements as a result of dohsa-hou (Japanese body-oriented psychotherapy) for the elderly. The study divided participants into two homogeneous groups: an experimental group that attempted to improve upright balance by performing dohsa-hou, and a control group to establish the drop-off period for the effect of performing the given activities. The task processing time of Stroop Test and body sway and the situational anxiety during task processing of Stroop Tests were measured before and after the dohsa-hou and drop-off period. The results confirm that only the experimental group improved in body sway, had a shorter Stroop Color Test processing time and lower situational anxiety. From this study, it has been identified that: (a) information-processing capacities spared for posture control are affected by distribution of processing resources towards solving other cognitive tasks; and (b) the effect of the release of attention from threat-related information due to a decrease in attentional bias, which accompanied the decrease in situational anxiety, are primary factors in improving cognitive task performance. [ABSTRACT FROM AUTHOR]

Balance impairment is a principal symptom of cerebellar disease, but is poorly understood partly because subjects with heterogenous cerebellar and extracerebellar lesions have often been studied. Spinocerebellar ataxia type 6 (SCA6) provides an opportunity to understand balance dysfunction associated with a relatively homogenous cerebellar lesion. This study investigated stance instability in SCA6 and how it is affected by varying stance width. Body sway, as well as its directional preponderance and distribution across joints, was measured three-dimensionally in 17 SCA6 and 17 matched healthy control subjects. Subjects stood for 40 seconds on a stable surface with their eyes open and feet positioned at various stance widths (32, 16, 8, 4, and 0 cm). SCA6 subjects swayed faster than controls at every stance width. Decreasing the stance width produced a disproportionate increase in sway speed in SCA6 subjects, compared to controls. Directional preponderance of sway was dependent on stance width, but did not differ between groups. Joint instability was increased by reducing stance width in both groups, but there was greater instability of the ankle joint in the roll plane in the SCA6 group. Measures of global instability correlated strongly with disease severity measured with the Scale for the Assessment and Rating of Ataxia (r = 0.79). The sway characteristics suggest a disruption of sensorimotor processing for balance control in SCA6. The correlation with disease severity implies that balance impairment is a feature of progression of SCA6 clinical syndrome. With stance width standardized, the instability measures employed could provide sensitive, continuous outcome measures of longitudinal or therapeutic change. © 2012 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Objectives A prolonged-release formulation of melatonin (PR-M) is indicated for insomnia in patients aged 55 years and older. Because hypnotics result in impairments of body sway, it was important to evaluate the effect of 2 mg PR-M on postural stability in older adults at night. Methods Twenty-four healthy volunteers (12 women, 12 men, aged 55-64 years) completed a randomized, double-blind, single-dose, three-way crossover study of postural stability of PR-M 2 mg, zolpidem 10 mg (active control) or placebo. Subjects were tested for body sway 30 min before, 1.5 and 4 h after dosing. Parameters tested were the area of the 95% confidence ellipse enclosing the center of pressure (COP; [A95]) and COP path length. Results Zolpidem significantly increased the A95 (both eyes conditions at all time points) and path length of COP. PR-M had no effect on A95 (both 'eyes closed' and 'eyes open' conditions at all time points) compared with placebo and increased COP path length by 10% at 4 h post-dose in open but not closed eyes condition. No serious adverse events were observed. Conclusions In older adults, evening PR-M intake did not impair postural stability during the night. The postural instability with zolpidem demonstrated assay sensitivity and validated the outcome. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary Alterations of body sway caused by isometric contractions of the jaw muscles have been reported previously. The objective of this study was to test if motor tasks of the masticatory system with different control demands affect body posture differently during quiet stance. Position and sway displacements of the center of foot pressure (COP) were measured for 20 healthy subjects who either kept the mandible at rest or performed unilateral and bilateral maximum voluntary teeth clenching, feedback-controlled biting tasks at submaximum bite forces, or unilateral chewing. Two weeks later the measurements were repeated. Compared with quiet stance, the COP results revealed significant changes during the feedback-controlled biting tasks. Robust sway reduction and anterior displacement of the COP were observed under these conditions. Body oscillations were not significantly affected by maximum bites or by unilateral chewing. For most of the variables investigated there were no significant differences between unilateral and bilateral biting. Robust sway reduction during feedback-controlled biting tasks in healthy subjects involved a stiffening phenomenon that was attributed to the common physiological repertoire of posture control, and might optimize the stability of posture under these conditions. [ABSTRACT FROM AUTHOR]

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT • Body sway increases in older adults and may lead to an increase in the risk of falling. • The problem of impaired stability in the elderly may be compounded by the use of hypnotics, which have been associated with an increased risk of next-day falls as well as drowsiness. • The potential adverse effects of hypnotic drugs on steadiness may be exacerbated during the night, in the event that an individual needs to get out of bed. WHAT THIS STUDY ADDS • This study examines the effects of gaboxadol (an investigational treatment for insomnia), zolpidem (a current hypnotic included as an active control) and placebo on body sway and attention/information processing ability following bedtime dosing in elderly subjects who were woken during the night for assessments. • Zolpidem and gaboxadol increased body sway at various time points during the night relative to placebo; at 1.5 h post dose, the time of peak concentrations of both drugs, gaboxadol produced less impairment than zolpidem. • Compared with placebo, neither gaboxadol nor zolpidem impaired attention/information-processing ability as assessed by critical flicker fusion. AIMS To evaluate tolerability, pharmacokinetics and night-time effects on body sway and critical flicker fusion (CFF) of gaboxadol following bedtime dosing in healthy elderly subjects. METHODS Subjects (17 women, seven men) aged 65–75 years received gaboxadol 10 mg, zolpidem 5 mg (active control) or placebo at 22.00 h in a three-period, randomized, double-blind crossover study. They were awakened during the night for evaluation of body sway and CFF. Pharmacokinetics of gaboxadol were assessed during a fourth single-blind treatment period. Adverse events were recorded throughout the study. RESULTS The number of subjects with adverse events was 14 for gaboxadol 10 mg, seven for zolpidem and nine for placebo; most were mild or moderate in intensity. Two women discontinued the study following gaboxadol; one vomited and one experienced a severe vasovagal syncope after venepuncture. Mean gaboxadol tmax was 2 h, t½ was 1.7 h, AUC0–∞ was 430 ng·h ml−1 and Cmax was 139 ng ml−1. At 1.5 h and 4 h post dose, zolpidem increased body sway relative to placebo ( P < 0.01). Gaboxadol increased body sway at 4 h ( P < 0.001) and 8 h ( P < 0.05) relative to placebo. At 1.5 h, the time point closest to peak drug concentrations, zolpidem increased body sway compared with gaboxadol ( P < 0.01). Gaboxadol and zolpidem had no effects on CFF vs. placebo. CONCLUSIONS A bedtime dose of gaboxadol 10 mg was generally well tolerated. Changes in body sway at 1.5 h after bedtime dosing were smaller with gaboxadol 10 mg than with zolpidem 5 mg, whereas changes were similar at 4 h for both treatments and returned to near baseline at 8 h. [ABSTRACT FROM AUTHOR]

We examined the influence of fatigue in the lower leg muscles on the centre of pressure sway during a static upright posture. Twelve healthy young men and women completed the exercise stress test on the triceps surae muscle and continued the exercise until their muscles were fatigued. A centre of pressure sway of 1 min was carried out in a Romberg posture at rest and at different instants after fatiguing exercise: immediately after, 5 min after, and 10 min after exercise. Blood lactate concentration was measured from fingertip samples taken before and immediately after exercise. To evaluate body sway, the following four centre of pressure sway factors were selected: unit time sway, front-back sway, left-right sway, and high-frequency band power spectrum. The measurement device used was an Anima stabilometer (G5500). The data sampling frequency was 20 Hz. After exercise, blood lactate concentration was increased. Significant differences were observed in unit time sway, front-back sway, and high-frequency band power spectrum immediately after exercise. These values eventually returned to baseline levels 5 min after fatiguing exercise. [ABSTRACT FROM AUTHOR]

Imagery plays an important role in hypnotic phenomena. Recent findings have shown, however, that hypnotized subjects with high (Highs) and low (Lows) susceptibility to hypnosis undergoing guided imagery tasks centred on specific sensory modalities share similar visual imagery ability, but Highs obtain better imagery than Lows when tactile instructions are given. The aim of this experiment was to confirm this finding using instructions of globally reduced perception instead of suggestions centred on specific sensory modalities, assuming that the preferred imagery modality would be the least easily suppressed. Changes in body sway (that are sensitive to cognitive activity because postural control requires attention) were used as indices of possible differences in the cognitive task load in Highs and Lows. The results confirmed the hypothesis that Highs and Lows differ in their preferred imagery modalities, and showed that Highs' body sway was not modified by the simultaneous imagery of globally reduced perception, while Lows increased their sway while perceiving the decreased sensory availability. The Discussion focuses on the similar networks involved in imagery and perception and on possible differences between Highs and Lows in the mechanisms of imagery/perception and sensory-motor integration. Copyright © 2007 British Society of Experimental & Clinical Hypnosis. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The present study examined the relationships between shooting accuracy and shooters' behavioral performance, i.e., postural balance and gun barrel stability, among novice rifle shooters in intra- and inter-individual levels. Postural balance and rifle stability were assessed in terms of anteroposterior (VELAP) and mediolateral (VELML) sway velocity of the movement of center of pressure, and horizontal (DEVH) and vertical (DEVV) deviation of the aiming point. The participants ( n=58) performed 30 shots in the standing position at a distance of 10 m from the target. The data showed that shooting accuracy was related to postural balance and rifle stability, but only at the inter-individual level. The correlation coefficients between shooting score and behavioral performance variables ranged from −0.29 to −0.45. The stepwise multiple regression analysis revealed that the VELML and the DEVH as independent variables accounted for 26% of the variance in the shooting score. The results also suggested that postural balance is related to the shooting accuracy both directly and indirectly through rifle stability. As the role of postural balance appeared to be important in shooting performance, the use of additional balance training programs to improve a shooter's postural skills should be encouraged. [ABSTRACT FROM AUTHOR]

This paper discusses the induced effect on the body sway when an iteratively rotating visual wide-field stimulus and an auditory stimulus with a moving sound image are presented simultaneously with synchronization. When the sound image is iteratively rotated in phase relative to the iteratively rotating visual stimulus, the induced effect on the body sway increases when the visual angle of the visual stimulus is increased, compared to the case in which the auditory stimulus is presented in the opposite phase. When the visual angle of the visual stimulus is reduced, on the other hand, there is no difference in the induced effects between the in-phase and opposite-phase conditions. These results suggest that when the visual and auditory stimuli are simultaneously presented, the induced effects of the visual and auditory stimuli on body sway are not simply added, but that there is an interaction between the two effects. It is suggested that the induced effect due to the interaction between the visual and auditory stimuli depends on the visual angle of the visual stimulus, and is enhanced by the wider field visual stimulus. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 85(10): 31–39, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.1123 [ABSTRACT FROM AUTHOR]

Depth information was studied as part of an investigation of the way that perceptual information from binocular vision affects the human sense of motion. Using flat objects and objects with depth, either moving or still, viewed at various angles, we measured the body sway, head motion, and eye motion of subjects in a standing position. For the flat targets, a minimum visual angle of approximately 45° was needed for relatively stable control, while for 3D targets an angle of 22.5° or 45° was necessary. At a visual angle of approximately 45° the influence of visual data on postural control changed. There were considerable differences between the responses to the flat and 3D targets before and during stimulus motion. The measurements of head and eye movement showed good agreement between body sway and head movement at frequencies in the vicinity of 0.2 Hz. The 3D targets produced more frequent OKN, indicative of more stable control than in the case of flat targets. © 1997 Scripta Technica, Inc. Electron Comm Jpn Pt 3, 80(4): 83–92, 1997 [ABSTRACT FROM AUTHOR]

This was a randomized double blind, placebo-controlled cross over study performed on 12 healthy female volunteers. It consisted of three treatment sessions of 7 days separated by a one week wash out period. The objectives of the study were to assess the sedative activity of 2 muscle relaxant drugs: chlormezanone (600mg daily) and thiocolchicoside(16 mg daily) after a single oral administration and at steady state (day 7). The drugs were administered orally, during catch treatment period as 3 capsules daily for 7 days. Assessment criteria explored psychometric tests, body sway and subjective feeling rating scales. Chlormezanone induced objective disturbances of vigilance and concentration characterized by a decrease in the performance of an arithmetic calculation test and an increase in body sway are recorded in comparison with thiocolchicoside and placebo. These impairments were mainly marked on steady state. Most of the volunteers (10 over 12) complained of drowsiness throughout this treatment. Thiocolchicoside was devoided of any objective or subjective sedative side effect. [ABSTRACT FROM AUTHOR]

The effects on CEF.G, psychomotor performance and attention of diazepam 10mg, RU 43028 100 mg, RU 32698 100 mg and placebo administered orally have been investigated in 12 healthy subjects in a double-blind controlled study. The effects of the compounds were evaluated by objective tests (CEEG, measurement of body sway, critical flicker fusion, visual reaction time, tapping test, arithmetical calculation) and subjective measurements (visual analogue scales and side-effects questionnaire). Measurements were taken before treatment and after 30 mm. 2 h, 3.5 h and 6.5 h. Placebo and RU 43028 did not affect any of the tests used. Diazepam induced an increase in beta rhythms and a decrease in theta and alpha rhythms on CEEG. These expected patterns were correlated with plasma concentrations. It also induced sedative side-effects characterized by an increase of body sway and reaction time and a decrease of CEF and arithmetical calculation. RU 32698 displayed on atypical profile on CEEG with a reduction of alpha and theta rhythms without changes in beta and delta rhythms. It did not have any psychometric incapacitating effect. [ABSTRACT FROM AUTHOR]

The published Literature on the effects of single oral doses of psychoactive drugs on body sway in normal healthy young volunteers has been reviewed. Several methods are used to quantify sway objectively, including mechanical devices, balance platforms, and non-contact techniques. No one method emerges as being most appropriate for use in psychopharmacology. Total sway path and Fourier analysis are the variables commonly studied. Although many factors can influence sway they have little impact on well-designed studies. Ethanol has been consistently shown to increase body sway at doses above 0·5g/kg, benzodiazepines also increase sway; both probably acting at a central site(s). Various other psychoactive drugs have been shown to increase sway; however, none has yet been shown to decrease the amount of sway in normal subjects. The objective measurement of body sway is therefore a useful test for inclusion in a battery of tests for studies in human psychopharmacology. It also has a potential application in other areas of research requiring the assessment of central nervous system function, and in other subject groups, such as the elderly. [ABSTRACT FROM AUTHOR]

The 4K television was developed which had 4 times the pixels for full hi-vision giving a realistic image. in this study, we examined the effects of both 2D and 3D images on this high resolution 4K television. [ABSTRACT FROM AUTHOR]

The reliability of a direct, contact, mechanical method for the quantification of body sway is assessed. Methodological aspects in measurement of the eyes open/eyes closed ratio are also considered. [ABSTRACT FROM AUTHOR]

Presents the abstracts that will be presented in the poster session of the Society for Psychophysiological Research conference. "Prepulse Inhibition and the Psychological Refractory Period," by Melissa L. Rawley; "Sex Differences in Event Related Brain Responses in Semantic Priming," by Jerome Daltrozzo and Boris Kotchoubey; "Neuroelectric Assessment of Ecstasy Use in Young Adults," by Brian A. Lopez and John Polich.