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We present a first-look analysis of the JWST ERO data in the SMACS J0723.3-7327 cluster field. We begin by reporting 10 new spectroscopic redshifts from λobs = 1.8–5.2 μm NIRSpec medium-resolution (R  = λ/Δλ = 1000) data. These are determined via multiple high-SNR emission line detections with five objects at 1 < z < 3 displaying multiple rest-frame near-infrared Hydrogen Paschen lines, and five objects at 5 < z < 9 displaying rest-frame optical Oxygen and Hydrogen Balmer lines. For the five higher-redshift galaxies we extract fluxes in six NIRCam bands spanning λobs = 0.8–5 μm and perform spectral energy distribution fitting in combination with existing HST photometry. The 7 < z < 9 objects exhibit a U-shaped pattern across the F 277 W, F 356 W , and F 444 W bands, indicating a Balmer break seen in emission (Balmer jump) and high-equivalent-width [O  iii ] emission. This indicates an extremely young stellar population with the bulk of the current mass having formed within the past 10 Myr. We report robust stellar masses and mean stellar ages from our spectral fitting with the four z > 6 galaxies exhibiting low-stellar masses from log10 (M */M⊙) = 7.1–8.2, and correspondingly young mean stellar ages of only a few Myr. This work highlights the critical importance of combining large upcoming NIRCam surveys with NIRSpec follow-up to measure the spectroscopic redshifts necessary to robustly constrain physical parameters. [ABSTRACT FROM AUTHOR]

Background: Our previous work demonstrates that adults with ADHD produce more force at the fingertips compared to adults without ADHD. One possibility is that somatosensation is impaired in ADHD. However, ADHD is often comorbid with anxiety, and anxiety influences sensory responsivity., Aims: The goal of the current work was to evaluate differences in the self-report of sensory experiences in adults with and without ADHD, while controlling for internalizing behaviors., Methods and Procedures: Forty-five adults (23 with ADHD) completed a semi-structured interview for the diagnosis of ADHD, the Adolescent/Adult Sensory Profile (AASP), and the Achenbach Adult Self Report (ASR)., Outcomes and Results: Adults with ADHD reported more hyper- and hypo- sensitivity compared to adults without ADHD, even when controlling for internalizing behaviors. Specifically, between group differences were found for low registration, sensation seeking, and sensory sensitivity scores, but not for sensation avoiding, and for movement, visual, touch, activity, audition, or taste/smell., Conclusions and Implications: These findings demonstrate that sensory hyper- and hypo- sensitivity may be features of ADHD in adults. Further, they demonstrate that internalizing behaviors influence the perception of sensory experiences and thus should be accounted for in studies of sensory processing, integration, and modulation in adults with ADHD., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Objective: The purpose of this study was to examine simultaneously the level of physiological arousal and the postural response to external perturbations in people post-stroke compared to age-matched controls to build a more comprehensive understanding of the effect of stroke on postural control and balance self-efficacy., Methods: Participants stood with each foot on separate force platforms. Ten applications of loads of 2% body weight at the hips perturbed the participant anteriorly under two conditions: investigator-triggered or self-triggered (total 20). Electrodermal activity (EDA; measurement of physiological arousal), electromyography (EMG) of the ankle plantarflexor muscles and anterior-posterior center of pressure measurements were taken pre-perturbation (anticipatory) and post-perturbation (response) and compared between the initial (first two) and final (last two) perturbations., Results: Participants post-stroke demonstrated significantly higher levels of anticipatory EDA and anticipatory paretic plantarflexor EMG during both self- and investigator-triggered conditions compared to controls. Anticipatory EDA levels were higher in the final perturbations in participants post-stroke in both conditions, but not in controls. Habituation of the EDA responses post-perturbation was exhibited in the self-triggered perturbations in controls, but not in participants post-stroke., Conclusions: Physiological arousal and postural control strategies of controls revealed habituation in response to self-triggered perturbations, whereas this was not seen in participants post-stroke., Significance: Understanding the physiological arousal response to challenges to standing balance post-stroke furthers our understanding of postural control mechanisms post-stroke., (Copyright © 2017. Published by Elsevier B.V.)

The reliability of triceps surae electromyographic responses to standing perturbations in people after stroke and healthy controls is unknown. High-Density surface Electromyography (HDsEMG) is a technique that records electromyographic signals from different locations over a muscle, overcoming limitations of traditional surface EMG such as between-day differences in electrode placement. In this study, HDsEMG was used to measure responses from soleus (SOL, 18 channels) and medial and lateral gastrocnemius (MG and LG, 16 channels each) in 10 people after stroke and 10 controls. Timing and amplitude of the response were estimated for each channel of the grids. Intraclass Correlation Coefficient (ICC) and normalized Standard Error of Measurement (SEM%) were calculated for each channel individually (single-channel configuration) and on the median of each grid (all-channels configuration). Both timing (single-channel: ICC=0.75-0.96, SEM%=5.0-9.1; all-channels: ICC=0.85-0.97; SEM%=3.5-6.2%) and amplitude (single-channel: ICC=0.60-0.91, SEM%=25.1-46.6; ICC=0.73-0.95, SEM%=19.3-42.1) showed good-to-excellent reliability. HDsEMG provides reliable estimates of EMG responses to perturbations both in individuals after stroke and in healthy controls; reliability was marginally better for the all-channels compared to the single-channel configuration., (Copyright © 2015 Elsevier B.V. All rights reserved.)

This study compared self-induced stepping reactions of seventeen participants after stroke and seventeen controls. Surface electromyographic (EMG) signals were recorded bilaterally from the soleus (SOL), tibialis anterior (TA), biceps femoris (BF) and rectus femoris (RF) muscles. Principal component analysis (PCA) was used to reduce the data into muscle activation patterns and examine group differences (paretic, non-paretic, control leg). The first principal component (PC1) explained 46.7% of the EMG signal of the stepping leg. Two PCs revealed distinct activation features for the stepping paretic leg: earlier TA onset at step initiation and earlier BF and SOL onset at mid-step. For the stance leg, PC1 explained 44.4% of the EMG signal and significant differences were found in the non-paretic leg compared to paretic (p < 0.001) and control (p < 0.001). In PC1, at step onset the BF and SOL EMG and the RF and TA EMG were increased over the latter half of the step. No PC loadings were distinct for the paretic leg during stance, however differences were found in the non-paretic leg: earlier TA burst and increased BF and SOL EMG at step initiation. The results suggest impairments in the paretic leg when stepping and compensatory strategies in the non-paretic stance leg., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Objective: This study investigated the behavior of medial gastrocnemius (GM) motor units (MU) during external perturbations in standing in people with chronic stroke., Methods: GM MUs were recorded in standing while anteriorly-directed perturbations were introduced by applying loads of 1% body mass (BM) at the pelvis every 25-40s until 5% BM was maintained. Joint kinematics, surface electromyography (EMG), and force platform measurements were assessed., Results: Although external loads caused a forward progression of the anterior-posterior centre of pressure (APCOP), people with stroke decreased APCOP velocity and centre of mass (COM) velocity immediately following the highest perturbations, thereby limiting movement velocity in response to perturbations. MU firing rate did not increase with loading but the GM EMG magnitude increased, reflecting MU recruitment. MU inter spike interval (ISI) during the dynamic response was negatively correlated with COM velocity and hip angular velocity., Conclusions: The GM utilized primarily MU recruitment to maintain standing during external perturbations. The lack of MU firing rate modulation occurred with a change in postural central set. However, the relationship of MU firing rate with kinematic variables suggests underlying long-loop responses may be somewhat intact after stroke., Significance: People with stroke demonstrate alterations in postural control strategies which may explain MU behavior with external perturbations., (Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)