Search

In severe epileptic encephalopathies, epileptic activity contributes to progressive cognitive dysfunction. Several epileptic encephalopathies share the trait of spike-wave activation during non-rapid eye movement sleep (EE-SWAS), a state dominated by sleep oscillations known to coordinate offline memory consolidation. How epileptic activity impacts these thalamocortical sleep oscillations has not been directly observed in humans. Using a unique dataset of simultaneous human thalamic and cortical recordings in subjects with and without EE-SWAS, we reconcile prior conflicting observations about how epileptic spikes coordinate with sleep oscillations and provide direct evidence for epileptic spike interference of sleep spindle production. We find that slow oscillations facilitate both epileptic spikes and sleep spindles during stage 2 sleep (N2) at different phases of the slow oscillation. We show that sleep activated cortical epileptic spikes propagate to the thalamus (thalamic spike rate is increased after a cortical spike, p∼0). Thalamic spikes increase the spindle refractory period (p

Purpose To compare anterior cruciate ligament (ACL) autograft reconstruction using fixed-looped suspensory versus expandable femoral fixation through the anteromedial portal. Methods After we performed prospective power analysis and obtained institutional review board, 70 patients with ACL rupture were block randomized to the expandable or suspensory femoral fixation group (35 in each group). All patients received autologous hamstring autograft through the anteromedial portal and fixed with a sheath-screw system in the tibia. The primary outcome measures were anteroposterior knee stability at 2 years’ follow-up measured using the KT-1000 arthrometer and the degree of femoral and tibial tunnels’ widening measured by the use of computed tomography imaging performed immediately postoperative and 12 months postsurgery. Secondary outcome measures included pain score on a visual analog scale, the subjective International Knee Documentation Committee 2000 assessment form, the Lysholm score, and the Tegner activity scale at 3, 6, 12, and 24 months. Results Twenty-four patients were excluded from further analysis, leaving a total of 48 patients (24 in each group) for the final evaluation. The anteroposterior knee stability (KT-1000) showed no difference between groups at 24 months’ follow-up (P = .31). The percentile widening (%) of femoral and tibial tunnel at 1-year follow-up showed no difference also, except for greater values at the tibial coronal point T2 (P = .065) and tibial sagittal point T1 (P = .033) in the group of cortical buttons. Secondary clinical outcomes showed no statistical differences between groups at 3, 6, 12, and 24 months’ postoperatively. Numerical pain scale (visual analog scale) was similar in both groups except for postoperative day 7, where the AperFix group showed better results (P = .014). There were no major intraoperative and late postoperative complications in any of the groups. Conclusions Our results showed no significant differences in knee anteroposterior stability, tunnel enlargement or other clinical outcomes comparing expandable versus cortical button fixation in anteromedial hamstrings ACL reconstruction. Level of Evidence Level II, randomized controlled trial.

Introduction The 1/f spectral slope of the electroencephalogram (EEG) estimated in the gamma frequency range has been shown to reflect neural excitation/inhibition ratio and synchronization level within local neural populations. It was proposed as an arousal marker that differentiates wake, non-rapid eye movement (NREM) sleep, and rapid eye movement (REM) sleep. These stages exhibit progressively steeper 30-45 Hz slopes, interpreted in terms of increasing cortical inhibition. Here we sought to replicate these findings in a larger sample and provide a comprehensive characterization of how slope changes with age, sex, and its test-retest reliability as well as potential confounds that could affect the slope estimation. Methods After stringent exclusions and quality control, our final sample included 10,255 whole-night polysomnograms (PSGs) on 7,312 individuals 2,943 of whom had a second PSG, from the National Sleep Research Resource (NSRR). All preprocessing steps were performed using an open-source Luna package and the spectral slope was estimated by fitting log-log linear regression models on the absolute power from 30 to 45 Hz separately for wake, NREM and REM stages. We described sources of variation in the spectral slope (both within and between individuals) and its relationship to other sleep parameters including power and interhemispheric coherence. Results There was unambiguous statistical support for the hypothesis that, within individuals, the mean spectral slope grows steeper going from wake to NREM to REM sleep. We found that the choice of mastoid referencing scheme modulated the extent to which electromyogenic or electrocardiographic artifacts were likely to bias 30-45 Hz slope estimates, as well as other sources of technical, device-specific bias. Nonetheless, within individuals, slope estimates were relatively stable over time. Both cross-sectionally and longitudinal, slopes tended to become shallower with increasing age, particularly for REM sleep; males tended to show flatter slopes than females across all states. Although conceptually distinct, spectral slope did not predict sleep state substantially better than other summaries of the high-frequency EEG power spectrum (>20 Hz, in this context) including beta band power, however. In contrast to the common conception of the REM EEG as relatively wake-like (i.e. ‘paradoxical’ sleep), REM and wake were the most divergent states for multiple metrics, with NREM exhibiting intermediate profiles. Under a simplified modeling framework, changes in spectral slope could not, by themselves, fully account for the observed differences between states, if assuming a strict power-law model. Conclusion Although the spectral slope is appealing, theoretically inspired parameterization of the sleep EEG, we underscore some practical considerations that should be borne in mind when applying it in diverse datasets. Future work will be needed to fully characterize state-dependent changes in the aperiodic portions of the EEG power spectra, which appear to be consistent with, albeit not fully explained by, changes in the spectral slope. Support (If Any)

A range of explanations have been advanced for the systems of colour names found in different languages. Some explanations give special, fundamental status to a subset of colour categories. We argue that a subset of colour categories, if fundamental, will be coherent - meaning that a non-trivial criterion distinguishes them from the other colour categories. We test the coherence of subsets of achromatic (white, black and grey), primary (white, black, red, green, yellow, blue) and basic (primaries plus brown, orange, purple, pink and grey) colour categories in English. Criteria for defining colour categories were expressed in terms of behavioural, linguistic and geometric features derived from colour naming and linguistic usage data; and were discovered using machine learning methods. We find that achromatic and basic colour categories are coherent subsets but not primaries. These results support claims that the basic colour categories have special status, and undermine claims about the fundamental role of primaries in colour naming systems.

[Purpose] This study aimed to examine the thermal skin responses (thermal buildup and retention rate) to instrument-assisted soft tissue mobilization (IASTM) procedures applied on hamstrings at different angles. [Participants and Methods] Thirty university students (age: 20 ± 4 years, weight: 70.61 ± 9.11 kg, height: 168.5 ± 7.5 cm) received three sessions of 10-min Ergon(®) IASTM treatment on their dominant limbs' hamstrings at 20°, 60°, and 90° application angles, respectively. The skin temperature was measured with a thermometer immediately before and after treatment, and every minute thereafter until it returned to the baseline value. [Results] IASTM resulted in a significant increase in skin temperature irrespective of the application angle. The thermal retention rate produced by the treatment at a 90° angle was significantly higher than that produced by the 20° application angle (78.9 vs. 64.53 min). No significant differences were observed between the 60° and 90° angle applications (72.5 vs. 78.9 min). [Conclusion] IASTM application at 60° and 90° angles can increase and retain the hamstring's skin temperature for more than an hour, creating the conditions for potential positive adaptations to local metabolism and muscle tone.

[Purpose] This study aimed to evaluate the posterior thigh's skin thermal responses to 448-kHz radiofrequency-based therapy applied either in the form of standard application (Indiba(®)Activ) or combined soft tissue treatment (Indiba(®)Fascia treatment). [Participants and Methods] Ten healthy males (22 ± 3 years of age, weight 75.2 ± 4.9 kg, height 178.5 ± 4.7) received four different treatments which included a) Indiba(®)Activ (IA) radiofrequency treatment, b) Indiba(®)Fascia (IF), c) Indiba(®)Activ placebo (IAP) and d) Indiba(®)Fascia Placebo (IFP) in the posterior thigh of their dominant lower limb, while the non-dominant served as the control. Skin temperature was recorded pre- and post-treatment and every minute until the surface temperature reached pre-treatment levels using a wireless infrared thermometer. [Results] Both radiofrequency-based therapy groups IA and IF led to a significant increase in skin temperature compared to placebo applications. The IF intervention led to an average retention of elevated temperature for 164.2 minutes compared to 54.8 minutes of IA, 23.17 of IFP and 17.6 minutes of IAP. [Conclusion] These findings indicate that radiofrequency treatment at 448 kHz can induce and sustain significant thermal skin adaptations reflecting an increased blood circulation and metabolism of underlying tissues.

[Purpose] The purpose of this pilot study was to investigate the effectiveness of instrument-assisted soft tissue mobilization (IASTM), foam rolling, and athletic elastic taping on improving elite volleyball players' shoulder range of motion (ROM) and throwing performance. [Participants and Methods] Fifteen elite male volleyball players (mean age: 24 ± 4.54 years; mean height: 177 ± 0.08 cm; mean weight: 81 ± 7.71 kg) received shoulder Ergon IASTM, foam rolling, and elastic taping treatment in random order on both upper extremities once a week for three weeks. Pre-and post-treatment assessments of their shoulders' ROM and functional throwing performance were performed. [Results] Ergon IASTM technique resulted in significantly higher shoulder flexion ROM values than foam rolling and elastic taping. Foam rolling, in turn, showed better results than athletic elastic taping. Moreover, the Ergon IASTM technique resulted in significantly higher OSP values than athletic elastic taping. No significant differences were observed between the therapeutic interventions in terms of FTPI. [Conclusion] This pilot study on elite athletes provides evidence that both IASTM and foam rolling techniques may improve their passive shoulder ROM compared to elastic athletic taping while Ergon IASTM can also enhance their shoulder throwing performance.

We used the Land Colour Mondrian experiments in a Bayesian context to test the degree to which subjects vary in categorizing the colour of different patches, when each patch is made to reflect light of the identical wavelength-energy composition. The brain uses a ratio-taking mechanism to determine the ratio of light of every waveband reflected from a surface and from its surrounds. Our (Bayesian) hypothesis was that this ratio-taking mechanism is similar in all humans and therefore leads to a constant categorization of colours that differs little between them. The similarly categorized colours are the initial priors, with initial hues attached to them. Twenty subjects of different ethnic and cultural backgrounds, for all but one of whom English was not the primary language, viewed eight patches of different colour in two Mondrian displays; each patch, when viewed, was made to reflect identical ratios of long-, middle- and short-wave light. Subjects were asked to match the colour of the viewed patch with that of the Munsell chip coming closest in colour to that of the viewed patch, without using language. In terms of hue, there was less variability in matching warm hues than cool ones. In terms of colour categorization, there was little variability overall. We take the lack of significant variability between subjects in the matches made as a pointer to similar computational mechanisms being employed in different subjects to perceive colours, thus permitting them to assume that their categorization of colours has universal agreement and assent.

In the work reported here, we used the Land Color Mondrian experiments to test the degree to which subjects vary in their perception of color categories. Twenty subjects of different ethnic and cultural backgrounds, for all but one of whom English was not the primary language, viewed 8 patches of different color in two Mondrian displays; each patch, when viewed, was made to reflect identical ratios of long, middle and short wave light. Subjects were asked to match the color of the viewed patch with that of the Munsell chip coming closest in color to that of the viewed patch, without using language. Overall, there was no variability in categorizing colors as red, yellow, brown and green but a small variability in categorizing them as purple, blue, orange and turquoise. In terms of hue, we found significantly less variability in matching warm hues than in cool ones. We interpret the lack of significant variability between subjects in the matches made as a pointer to similar computational mechanisms being employed in different subjects to perceive colors, thus permitting subjects to assume that their categorization of colors has universal agreement and assent.

AB Introduction: Rhythmic gymnastics (RG) is an aesthetic event balancing between art and sport that also has a performance rating system (Code of Points) given by the International Gymnastics Federation. It is one of the sports in which competition results greatly depend on the judges' evaluation. In the current study, we explored the judges' performance in a five-gymnast ensemble routine. Methods: An expert-novice paradigm (10 international-level, 10 national-level, and 10 novice-level judges) was implemented under a fully simulated procedure of judgment in a five-gymnast ensemble routine of RG using two videos of routines performed by the Greek national team of RG. Simultaneous recordings of two-dimensional eye movements were taken during the judgment procedure to assess the percentage of time spent by each judge viewing the videos and fixation performance of each judge when an error in gymnast performance had occurred. Results: All judge level groups had very modest performance of error recognition on gymnasts' routines, and the best international judges reported approximately 40% of true errors. Novice judges spent significantly more time viewing the videos compared with national and international judges and spent significantly more time fixating detected errors than the other two groups. National judges were the only group that made efficient use of fixation to detect errors. Conclusions: The fact that international-level judges outperformed both other groups, while not relying on visual fixation to detect errors, suggests that these experienced judges probably make use of other cognitive strategies, increasing their overall error detection efficiency, which was, however, still far below optimum

Previous research in colour naming has been mostly focused on a small number of basic colour categories rather than towards the development of more subtle colour identifications. This has led to a preponderance of ‘basic’ colour schemes and has limited the visualisation of complex data. In this chapter, we present the findings of a long-running Internet-based colour naming experiment, designed to collect unconstrained colour names in multiple languages with their corresponding stimulus values. The data gathered are being used for the development of a colour-naming model that facilitates colour communication within and between different cultures.

Data is presented on the colour and spectralreflectances of stool samples from healthy young infants(mean age 6 days). The range of spectral reflectances iswell described by a pigment mixture model with threecomponents—a pale component corresponding to par-tially digested milk fats, a yellow component correspond-ing to bilirubin breakdown products, and a darkcomponent corresponding to meconium and bilirubin.Most stools were tan, beige or olive but white, grey andlight grey were also observed. V C 2014 Wiley Periodicals, Inc.Col Res Appl, 00, 000–000, 2014; Published Online 00 Month 2014 inWiley Online Library (wileyonlinelibrary.com). DOI 10.1002/col.21919 Key words: spectral measurement; pigment mixtures;stool colour INTRODUCTION Many parents are surprised and fascinated by the stoolcolours of their firstborn. Initially black, as the meconiumwhich is present in the bowel at birth is passed; progres-sively the stools become green and brown, as the meco-nium fraction reduces; until a characteristic mustardyellow colour is reached at roughly 4 days after birth.

We undertook psychophysical experiments to determine whether the color of the after-image produced by viewing a colored patch which is part of a complex multi-colored scene depends on the wavelength-energy composition of the light reflected from that patch. Our results show that, just as the color of a patch which is part of a complex scene is independent of the wavelength-energy composition of the light coming from it alone, but depends as well on the wavelength-energy composition of the light coming from its surrounds, so is the color of its after-image. Hence, traditional accounts of after-images as being the result of retinal adaptation or the perceptual result of physiological opponency, are inadequate. We propose instead that the color of after-images is generated after colors themselves are generated in the visual brain.

article i nfo Article history: The model of a stochastic decision process unfolding in motor and premotor regions of the brain was encoded in single-trial magnetoencephalographic (MEG) recordings while ten healthy subjects performed a sensori- motor Reaction Time (RT) task. The duration of single-trial MEG signals preceding the motor response, recorded over the motor cortex contralateral to the responding hand, co-varied with RT across trials accord- ing to the model's prediction. Furthermore, these signals displayed the same properties of a "rising-to-a- fixed-threshold" decision process as posited by the model and observed in the activity of single neurons in the primate cortex. The present findings demonstrate that non-averaged, single-trial MEG recordings can be used to test models of cognitive processes, like decision-making, in humans.

Unique hue settings of 185 observers under three room-lighting conditions were used to evaluate the accuracy of full and mixed chromatic adaptation transform models of CIECAM02 in terms of unique hue reproduction. Perceptual hue shifts in CIECAM02 were evaluated for both models with no clear difference using the current Commission Internationale de l'Eclairage (CIE) recommendation for mixed chromatic adaptation ratio. Using our large dataset of unique hue data as a benchmark, an optimised parameter is proposed for chromatic adaptation under mixed illumination conditions that produces more accurate results in unique hue reproduction. © 2011 Wiley Periodicals, Inc. Col Res Appl, 2013

Gender differences in colour naming were explored using a web-based experiment in English. Each participant named twenty colours selected from 600 Munsell samples, presented one at a time against a neutral background. Colour names and typing onset response times were registered. For the eleven basic colour terms, elicitation frequency was comparable for both genders. Females demonstrated more elaborated colour vocabulary, with more descriptors in general and more non-basic monolexemic terms; they also named colours faster than males. The two genders differ in the repertoire of frequent colour terms: a Bayesian synthetic observer revealed that women segment colour space linguistically more densely in the “warm” area whereas men do so in the “cool” area. Current “nurture” and “nature” explanations of why females excel in colour naming behaviour are considered.

We report the emergent functional connectivity of cortical areas during a visuo-perceptual discrimination task with or without the retention in memory of the location of visual targets using EEG. The networks were computed using multivariate Granger causality on groups of electrodes reflecting coarse-grained brain areas. The analysis showed that at alpha band (8-12Hz) there are no significant differences. In contrast, in beta and gamma band, we identified a top-down information flow pattern which was evident for the task that required the activation of the working memory mechanism.

Existing research in colour naming has been mostly focused on a small number of basic colour categories rather than towards the development of more subtle colour identifications. This often leads to an over-saturation in the use of 'basic' colour schemes and can limit the differentiation of new ideas. In this chapter, we present the findings of a free colour naming experiment which has been designed to collect multilingual colour names with their corresponding metric values. The data gathered are being used for the development of a colour naming model that facilitates colour communication within and between different cultures. © 2012 Woodhead Publishing Limited All rights reserved.

Observers are faster to detect a target among a set of distracters if the targets and distracters come from different color categories. This cross-boundary advantage seems to be limited to the right visual field, which is consistent with the dominance of the left hemisphere for language processing [Gilbert et al., Proc. Natl. Acad. Sci. USA 103, 489 (2006)]. Here we study whether a similar visual field advantage is found in the color identification task in speakers of Mandarin, a language that uses a logographic system. Forty late Mandarin-English bilinguals performed a blue-green color categorization task, in a blocked design, in their first language (L1: Mandarin) or second language (L2: English). Eleven color singletons ranging from blue to green were presented for 160 ms, randomly in the left visual field (LVF) or right visual field (RVF). Color boundary and reaction times (RTs) at the color boundary were estimated in L1 and L2, for both visual fields. We found that the color boundary did not differ between the languages; RTs at the color boundary, however, were on average more than 100 ms shorter in the English compared to the Mandarin sessions, but only when the stimuli were presented in the RVF. The finding may be explained by the script nature of the two languages: Mandarin logographic characters are analyzed visuospatially in the right hemisphere, which conceivably facilitates identification of color presented to the LVF.

In an unconstrained colour naming experiment conducted over the web, 330 participants named 600 colour samples in English. The 30 most frequent monolexemic colour terms were analyzed with regards to frequency, consensus among genders, response times, consistency of use, denotative volume in the Munsell and OSA colour spaces and inter-experimental agreement. Each of these measures served for ranking colour term salience; rankings were then combined to give a composite index of basicness. The results support the extension of English inventory from the 11 basic colour terms of Berlin and Kay to 13 terms by the addition of lilac and turquoise.