Repeated Context-Specific Actions Disrupt Feedforward Adjustments in Motor Commands in Younger and Older Adults.

The flexibility of the motor system to adjust a planned action before or during the execution of the movement in response to sensory information is critical for preventing errors in motor control. As individuals age, this function declines, leading to an increased incidence of motor errors. While sensory processing and cognitive decline are known contributors to this impairment, here, we test the hypothesis that repetition of context-specific planned actions interferes with the adjustment of feedforward motor commands. Younger and older participants were instructed to grasp and lift a T-shaped object with a concealed, off-sided center of mass and minimize its roll through anticipatory force control, relying predominantly on predictive model-driven planning (i.e., sensorimotor memories) developed through repeated lifts. We selectively manipulate the number of trial repeats with the center of mass on one side before switching it to the other side of the T-shaped object. The results showed that increasing the number of repetitions improved performance in manipulating an object with a given center of mass but led to increased errors when the object's center of mass was switched. This deleterious effect of repetition on feedforward motor adjustment was observed in younger and older adults. Critically, we show these effects on an internal model-driven motor planning task that relies predominantly on sensorimotor memory, with no differences in sensory inputs from the repetition manipulation. The findings indicate that feedforward motor adjustments are hampered by repetitive stereotyped planning and execution of motor behavior.

Facilitatory effect of low-pulse repetition frequency ultrasound on release of extracellular vesicles from cultured myotubes.

PURPOSE: Extracellular vesicles (EVs) serve as carriers of intracellular factors with therapeutic effects, including tissue regeneration and attenuation of inflammatory responses. The majority of EVs in vivo are derived from skeletal muscle, which is reported to have anti-inflammatory effects. While high-intensity pulsed ultrasound (US) irradiation has been shown to promote EV secretion from myotubes, the impact of pulse repetition frequency, a US parameter affecting pulse length, on EV release remains unclear. This study aimed to investigate the impact of pulse repetition frequency of US on the release of EVs from myotubes. METHODS: C2C12 myoblasts were used in this study. After differentiation into C2C12 myotubes, US was performed for 5 min at an intensity of 3.0 W/cm2, duty cycle of 20%, acoustic frequency of 1 MHz, and different pulse repetition frequencies (100 Hz, 10 Hz, or 1 Hz). After 12 h, EVs and cells were collected for subsequent analyses. RESULTS: US did not cause a reduction in cell viability across all US groups compared to the control. The concentration of EVs was significantly higher in all US groups compared to the control group. In particular, the highest increase was observed in the 1-Hz group on EV concentration as well as intracellular Ca2+ level. CONCLUSION: This study investigated the effect of three different pulse repetition frequencies of US on the release of EVs from cultured myotubes. It is concluded that a low-pulse repetition frequency of 1 Hz is the most effective for enhancing EV release from cultured myotubes with pulsed ultrasound.

Risk factors for suicide reattempt: a systematic review and meta-analysis.

BACKGROUND: Suicide is one of the main external causes of death worldwide. People who have already attempted suicide are at high risk of new suicidal behavior. However, there is a lack of information on the risk factors that facilitate the appearance of reattempts. The aim of this study was to calculate the risk of suicide reattempt in the presence of suicidal history and psychosocial risk factors and to estimate the effect of each individual risk factor. METHODS: This systematic review and meta-analysis were conducted following the PRISMA-2020 guidelines. Studies on suicide reattempt that measured risk factors were searched from inception to 2022. The risk factors studied were those directly related to suicide history: history of suicide prior to the index attempt, and those that mediate the transition from suicidal ideation to attempt (alcohol or drug misuse, impulsivity, trauma, and non-suicidal self-injury). RESULTS: The initial search resulted in 11 905 articles. Of these, 34 articles were selected for this meta-analysis, jointly presenting 52 different effect sizes. The pooled effect size across the risk factors was significant (OR 2.16). Reattempt risk may be increased in presence of any of the following risk factors: previous history, active suicidal ideation, trauma, alcohol misuse, and drug misuse. However, impulsivity, and non-suicidal self-injury did not show a significant effect on reattempt. CONCLUSION: Most of the risk factors traditionally associated with suicide are also relevant when talking about suicide reattempts. Knowing the traits that define reattempters can help develop better preventive and intervention plans.

Secondary language impairment in posterior cortical atrophy: insights from sentence repetition.

Introduction: Posterior cortical atrophy (PCA) is a neurodegenerative syndrome characterized by progressive impairment in visuospatial and perceptual function linked to atrophy of the occipito-parietal cortex. Besides the salient visual impairment, several studies have documented subtle changes in language may also be present. Sentence repetition is a highly constrained linguistic task involving multiple linguistic and cognitive processes and have been shown to be impaired in other AD spectrum disorders, with little consensus on its relevance in PCA. This aim of this study was to further delineate the linguistic and cognitive features of impaired language in PCA using a sentence repetition task. Method: Seven PCA patients and 16 healthy controls verbally repeated 16 sentences from the Boston Diagnostic Aphasia Examination. Responses were transcribed orthographically and coded for accuracy (percentage accuracy; percentage Correct Information Units; Levenshtein Distance) and for temporal characteristics (preparation duration (ms); utterance duration (ms); silent pause duration (ms); speech duration (ms); dysfluency duration (ms)). The potential modulating effects of attentional control and working memory capacity were explored. Results: PCA patients showed lower overall accuracy with retained semantic content of the sentences, and lower phonological accuracy. Temporal measures revealed longer preparation and utterance duration for PCA patients compared to controls, alongside longer speech duration but comparable dysfluency duration. PCA patients also showed comparable silent pause duration to controls. Attentional control, measured using the Hayling sentence completion task, predicted accuracy of sentence repetition. Discussion: The findings suggest that sentence repetition is impaired in PCA and is characterized by phonological, response planning and execution difficulties, underpinned in part by attentional control mechanisms. The emerging profile of language impairment in PCA suggests vulnerability of similar cognitive systems to other Alzheimer's syndromes, with subtle differences in clinical presentation.

Wernicke's functional neuroanatomy model of language turns 150: what became of its psychological reflex arcs?

Wernicke (Der aphasische Symptomencomplex: Eine psychologische Studie auf anatomischer Basis. Cohn und Weigert, Breslau.  https://wellcomecollection.org/works/dwv5w9rw , 1874) proposed a model of the functional neuroanatomy of spoken word repetition, production, and comprehension. At the heart of this epoch-making model are psychological reflex arcs underpinned by fiber tracts connecting sensory to motor areas. Here, I evaluate the central assumption of psychological reflex arcs in light of what we have learned about language in the brain during the past 150 years. I first describe Wernicke's 1874 model and the evidence he presented for it. Next, I discuss his updates of the model published in 1886 and posthumously in 1906. Although the model had an enormous immediate impact, it lost influence after the First World War. Unresolved issues included the anatomical underpinnings of the psychological reflex arcs, the role of auditory images in word production, and the sufficiency of psychological reflex arcs, which was questioned by Wundt (Grundzüge der physiologischen Psychologie. Engelmann, Leipzig. http://vlp.mpiwg-berlin.mpg.de/references?id=lit46 , 1874; Grundzüge der physiologischen Psychologie (Vol. 1, 5th ed.). Engelmann, Leipzig. http://vlp.mpiwg-berlin.mpg.de/references?id=lit806 , 1902). After a long dormant period, Wernicke's model was revived by Geschwind (Science 170:940-944. https://doi.org/10.1126/science.170.3961.940 , 1970; Selected papers on language and the brain. Reidel, Dordrecht, 1974), who proposed a version of it that differed in several important respects from Wernicke's original. Finally, I describe how new evidence from modern research has led to a novel view on language in the brain, supplementing contemporary equivalents of psychological reflex arcs by other mechanisms such as attentional control and assuming different neuroanatomical underpinnings. In support of this novel view, I report new analyses of patient data and computer simulations using the WEAVER++/ARC model (Roelofs 2014, 2022) that incorporates attentional control and integrates the new evidence.

Morphosyntactic skills in Arabic-speaking children with autism spectrum disorder: Evidence from error patterns in the sentence repetition task.

Background and aims: Although autism spectrum disorder (ASD) has not traditionally been associated with morphosyntactic impairments, some children with ASD manifest significant difficulties in this domain. Sentence Repetition (SRep) tasks are highly reliable tools for detecting morphosyntactic impairment in different languages and across various populations, including children with ASD. This study is among the first to evaluate morphosyntactic abilities of Palestinian-Arabic (PA) speaking children using a PA SRep task. Methods: A total of 142 PA-speaking children, aged 5-11, participated in the study: 75 children with typical language development (TLD) and 67 children with ASD. The PA SRep task targeted morphosyntactic structures of varying complexity (simple subject-verb-object [SVO] sentences, biclausal sentences, wh-questions, relative clauses). Children's accuracy scores were assessed across these structures and error patterns encompassing morphosyntactic and pragmatic aspects were analyzed. Results: Two subgroups of ASD emerged: 43% showed age-appropriate language skills (ASD + NL) pairing up with TLD peers, while 57% showed signs of morphosyntactic impairment (ASD + LI). Children in both groups exhibited a higher frequency of morphosyntactic errors than pragmatic ones. Children with ASD + LI showed difficulties with producing complex morphosyntactic structures, such as relative clauses and object wh-questions. Error analysis revealed that children in the ASD + LI group produced sentence fragments and simplified constructions when complex structures were targeted. Conclusions: The current study extends the cross-linguistic evidence of the heterogeneity of morphosyntactic profiles in children with ASD to Arabic-speaking children. Error analysis indicates that poor morphosyntax, rather than pragmatics, challenges children's performance on the SRep task. Implications: Our results emphasize the importance of comprehensive language assessment in children with ASD and underscore the need for tailored intervention plans targeting impaired morphosyntactic structures in some children with ASD.

Impact of climate change and oligotrophication on quality and quantity of lake primary production: A case study in Lake Biwa.

Global climate change and anthropogenic oligotrophication are expected to reshape the dynamics of primary production (PP) in aquatic ecosystems; however, few studies have explored their long-term effects. In theory, the PP of phytoplankton in Lake Biwa may decline over decades due to warming, heightened stratification, and anthropogenic oligotrophication. Furthermore, the PP of large phytoplankton, which are inedible to zooplankton, along with biomass-specific productivity (PBc), could decrease. In this study, data from 1976 to 2021 and active fluorometry measurements taken in 2020 and 2021 were evaluated. Quantitatively, the temporal dynamics of mean seasonal PP during 1971-2021 were assessed according to the carbon fixation rate to investigate relationships among environmental factors. Qualitatively, phytoplankton biomass, PP, and PBc were measured in two size fractions [edible (S) or inedible (L) for zooplankton] in 2020 and 2021, and the L:S balance for these three measures was compared between 1992 (low-temperature/high-nutrient conditions) and 2020-2021 (high-temperature/low-nutrient conditions) to assess seasonal dynamics. The results indicated that climate change and anthropogenic oligotrophication over the past 30 years have diminished Lake Biwa's PP since the 1990s, impacting the phenology of PP dynamics. However, the L:S balance in PP and PBc has exhibited minimal change between the data from 1992 and the 2020-2021 period. These findings suggest that, although climate change and oligotrophication may reduce overall PP, they may not markedly alter the inedible/edible phytoplankton balance in terms of PP and PBc. Instead, as total PP declines, the production of small edible phytoplankton may decrease proportionally, potentially affecting trophic transfer efficiency and material cycling in Lake Biwa.

Illusions of knowledge due to mere repetition.

Repeating information increases people's belief that the repeated information is true. This truth effect has been widely researched and is relevant for topics such as fake news and misinformation. Another effect of repetition, which is also relevant to those topics, has not been extensively studied so far: Do people believe they knew something before it was repeated? We used a standard truth effect paradigm in four pre-registered experiments (total N = 773), including a presentation and judgment phase. However, instead of "true"/"false" judgments, participants indicated whether they knew a given trivia statement before participating in the experiment. Across all experiments, participants judged repeated information as "known" more often than novel information. Participants even judged repeated false information to know it to be false. In addition, participants also generated sources of their knowledge. The inability to distinguish recent information from well-established knowledge in memory adds an explanation for the persistence and strength of repetition effects on truth. The truth effect might be so robust because people believe to know the repeatedly presented information as a matter of fact.

From psychophysiology to brain imaging: forty-five years MMN history of investigating acoustic change sensitivity.

Forty-five years have passed since the first publication of the mismatch negativity (MMN) event-related brain potential (ERP) component. The first 10 years of research hardly gained any particular attention of the scientific community interested in acoustic perception. Debates on the nature of sensation versus perception were going on, and the technical possibilities to record ERPs, called in general evoked potentials, were very limited. Subtle changes in pure tone frequency or intensity giving rise to the MMN component were first investigated in humans. The background of the theoretical model developed by Risto Näätänen was the orientation reaction model of E.N. Sokolov published in 1963 so that the MMN was seen first as an electrophysiological correlate of auditory change detection. This fundamental ability of the auditory system seen as crucial for survival led to the development of the first animal model of the MMN (Csépe et al. in Clin Neurophysiol 66: 571-578, 1987). Indeed, it was confirmed that the MMN was the brain correlate of subtle changes detected that might alert to potential threats in the environment and direct the behavioral orientation. The investigations performed after 2000 introduced complex models and more sophisticated methods, both in animal and human studies, so that the MMN method was on the way to become a tool on the first place and not the main goal of research. This approach was further strengthened by the increasing number of studies on different clinical populations aiming at future applications. The aim of our review is to describe and redefine what the MMN may reflect in auditory perception and to show why and how this brain correlate of changes in the auditory scene can be used as a valuable tool in cognitive neuroscience research. We refer to publications selected to underly the argument the MMN cannot be classified anymore as a sign of simple change detection and not all the indicators used to confirm how genuine the MMN elicited by variations of tones are valid for those to  speech contrasts. We provide a fresh view on the broadly used MMN models, provided by some influential publications as well as on the unwritten history of MMN research aiming to give revised picture on what the MMN may truly reflect. We show how the focus and terminology of the MMN research have changed and what kind of misunderstandings and seemingly contradictive results prevent the MMN community to accept a generally usable cognitive model.

Case fatality of repeated suicidal acts among suicide attempters in rural China: a retrospective cohort study.

Background: Individuals presenting to hospital due to suicide attempt are at high risk for repeated suicidal act, yet there are meager data on the extent to which repeated suicidal acts result in death. Methods: This retrospective cohort study was based on a general hospital self-harm register system in a rural county in China. Identified individuals who attempted suicide were contacted and followed up for up to 8 years. Main outcomes over follow-up were: 1) suicide death, 2) nonlethal suicide attempt, and 3) suicidal acts including suicide death and nonlethal attempt. Incidence densities, correlates, and case fatality of repeated suicidal acts were estimated. Findings: A total of 1086 individuals (two-thirds females, mean age 40.6 years) with a suicide attempt presenting to hospital (index attempt) were identified and followed up, with most of the index attempts by pesticide ingestion (79%). Over follow-up, there were 116 suicidal acts carried out by 108 individuals (69 females, 39 males), including 34 suicide deaths (21 females, 13 males), yielding a high case-fatality of 29.3%. During follow-up, suicide death rates were also high overall and in the first year of follow-up (846.7 and 1787.2 per 100,000 person years). Over follow-up, pesticide was the most common method (47/116) of repeated suicidal act and yielded a higher case-fatality than other methods (46.8% vs 17.4%, χ2 = 11.68, P < 0.001). The incidence densities of repeated suicidal acts and nonlethal attempts were low compared to rates reported in previous literature. Interpretation: Incidence densities of repeated suicidal acts in a rural China cohort were low compared to previous studies. However, rates of suicide deaths over follow-up were high, a result driven by the high case-fatality of suicidal acts and attributable to the common use of pesticides. Reducing suicidal acts with pesticides is a key target for suicide prevention in rural China. Funding: Beijing Municipal High Rank Public Health Researcher Training Program, Beijing Hospitals Authority Clinical Medicine Development of Special Funding Support, and Beijing Hospitals Authority's Ascent Plan.

The effect of transcranial ultrasound pulse repetition frequency on sustained inhibition in the human primary motor cortex: A double-blind, sham-controlled study.

BACKGROUND: Non-invasive brain stimulation techniques such as transcranial magnetic stimulation and transcranial direct current stimulation hold promise for inducing brain plasticity. However, their limited precision may hamper certain applications. In contrast, Transcranial Ultrasound Stimulation (TUS), known for its precision and deep brain targeting capabilities, requires further investigation to establish its efficacy in producing enduring effects for treating neurological and psychiatric disorders. OBJECTIVE: To investigate the enduring effects of different pulse repetition frequencies (PRF) of TUS on motor corticospinal excitability. METHODS: T1-, T2-weighted, and zero echo time magnetic resonance imaging scans were acquired from 21 neurologically healthy participants for neuronavigation, skull reconstruction, and the performance of transcranial ultrasound and thermal modelling. The effects of three different TUS PRFs (10, 100, and 1000 Hz) with a constant duty cycle of 10 % on corticospinal excitability in the primary motor cortex were assessed using TMS-induced motor evoked potentials (MEPs). Each PRF and sham condition was evaluated on separate days, with measurements taken 5-, 30-, and 60-min post-TUS. RESULTS: A significant decrease in MEP amplitude was observed with a PRF of 10 Hz (p = 0.007), which persisted for at least 30 min, and with a PRF of 100 Hz (p = 0.001), lasting over 60 min. However, no significant changes were found for the PRF of 1000 Hz and the sham conditions. CONCLUSION: This study highlights the significance of PRF selection in TUS and underscores its potential as a non-invasive approach to reduce corticospinal excitability, offering valuable insights for future clinical applications.

Was It Just a Dream? Aging and Dreaming the Psychoanalytic Process.

By revisiting the last years of a long psychoanalytic treatment of a female patient, a psychoanalyst reflects on her own development as a clinician and on the changes in her experience of psychoanalytic generativity. An increasing ability to understand patient's shifts between creativity and destructiveness brings about a different understanding of the process of mourning, while the shared aging of the analytic dyad highlights the difficulty of ending an analysis that has become a way of life.

The illusory certainty: Information repetition and impressions of truth enhance subjective confidence in validity judgments independently of the factual truth.

People not only judge repeatedly perceived information as more likely being true (the so-called truth effect) they also tend to be more confident after judging the validity of repeated information. These phenomena are assumed to be caused by a higher subjective feeling of ease (i.e., fluency) when processing repeated (vs. new) information. Based on the suggestion that a higher number of coherent mental activations is promoting a fluency experience, we argue that besides repetition an already existing information network, that is (nonspecific) prior knowledge, can enhance fluency. Following this argumentation, information repetition as well as the act of judging incoming information as being true (vs. false) should feed into subjective confidence - independently of the factual truth (when judging under uncertainty). To test this, we reanalyzed two published data sets and conducted a new study. In total, participants (N = 247) gave 29,490 truth judgments and corresponding ratings of subjective confidence while attending two judgement phases (i.e., 10 min and 1 week after the exposure phase in each experiment). Results showed that (a) repetition (in 3 of 3 data sets) and (b) impressions of truth (in 2 of 3 data sets) were systematically related to higher subjective confidence. Moreover, we found (c) a significant positive interaction between repetition and impressions of truth after both intervals in all data sets. Our analyses further underline the moderating effect of time: Influences of repetition significantly decreased with increasing time interval. Notably, the factual truth did not systematically affect any of the above reported effects.

Prime saliency in semantic priming with 18-month-olds.

This study investigated semantic priming in 18-month-old infants using the inter-modal priming technique, focusing on the effects of prime repetition on saliency. Our findings showed that prime repetition led to longer looking times at target referents for related primes compared to unrelated primes, supporting the existence of a structured semantic system in infants as young as 18 months. The results are consistent with both Spreading Activation and Distributed models of semantic priming. Additionally, our findings highlighted the impact of prime-target stimulus onset asynchronies (SOAs) on priming effects, revealing positive, negative, or no priming effects depending on the chosen SOA. A post-hoc explanation of this finding points to negative priming as a possible mechanism. The study also demonstrated the utility of the inter-modal priming task in studying lexical-semantic structure in younger infants with its diverse measures of infant behaviour.

Behavioral dynamics of neuroprotective macrophage polarization in neuropathic pain observed by GHz femtosecond laser two-photon excitation microscopy.

Macrophage polarization in neurotoxic (M1) or neuroprotective (M2) phenotypes is known to play a significant role in neuropathic pain, but its behavioral dynamics and underlying mechanism remain largely unknown. Two-photon excitation microscopy (2PEM) is a promising functional imaging tool for investigating the mechanism of cellular behavior, as using near-infrared excitation wavelengths is less subjected to light scattering. However, the higher-order photobleaching effect in 2PEM can seriously hamper its applications to long-term live-cell studies. Here, we demonstrate a GHz femtosecond (fs) 2PEM that enables hours-long live-cell imaging of macrophage behavior with reduced higher-order photobleaching effect-by leveraging the repetition rate of fs pulses according to the fluorescence lifetime of fluorophores. Using this new functional 2PEM platform, we measure the polarization characteristics of macrophages, especially the long-term cellular behavior in efferocytosis, unveiling the dynamic mechanism of neuroprotective macrophage polarization in neuropathic pain. These efforts can create new opportunities for understanding long-term cellular dynamic behavior in neuropathic pain, as well as other neurobiological problems, and thus dissecting the underlying complex pathogenesis.

Repetition blindness in a saccadic persistence of vision display.

A form of repetition blindness in visually unimpaired individuals was found for objects presented during saccades. Observers were asked to draw their percepts after making saccades across an LED strip that "painted" an image on their retinas by presenting sequential columns of a bitmap at a speed to match a 30-degree saccade. During experimental trials, repetitions of a single letter (either "A," "X," "H," or "V") were presented across saccades. Although an average of six letters were presented across each saccade, observers typically indicated perceiving only a single instance of the letter in their drawings. This inability to perceive multiple instances of a letter was not due to a limited region of attentional processing, as it only attained for multiple instances along the axis of the saccade-horizontal saccades did not affect perception of multiple letters along the vertical axis. This effect is likely due to selective suppression of visual areas during saccades.

Self-harm and suicide death in the three years following hospitalization for intentional self-harm in adolescents and young adults: A nationwide study.

Self-harm is frequent in youths. This study aimed to assess the risk of self-harm and mortality over a three-year period following self-harm hospitalization. Data were extracted from national databases in France. All patients aged 12 to 24 years and hospitalized for self-harm in 2013-2014 were included and compared to age- and sex-matched individuals with no self-harm hospitalization during this period. Cox proportional hazards regression models were used. Overall, 34,533 individuals were hospitalized for self-harm in 2013-2014 (70.8 % females, 79.6 % self-poisoning), with a peak among females aged 14-16. Comparison with 103,599 matched controls showed significantly higher rates of past self-harm, somatic and psychiatric disorders, and dispensed drugs in youth hospitalized for self-harm. During follow-up, they significantly more often repeated self-harm (20.9 vs. 0.1 %), died from any cause (0.6 vs 0.03 %) and from suicide (0.2 vs 0.01 %), particularly during the first year. The choice of a violent self-harm means at inclusion increased the risk of suicide during follow-up. Psychiatric disorders were a significant risk factor for all outcomes. In conclusion, at least one in five youths will self-harm, and one in two hundred will die in the three years following hospitalization for self-harm. Reinforced follow-up care is necessary in this population.

Myelin water quantification in multiple sclerosis using short repetition time adiabatic inversion recovery prepared-fast spin echo (STAIR-FSE) imaging.

Background: Myelin water imaging (MWI) is a myelin-specific technique, which has great potential for the assessment of demyelination and remyelination. This study develops a new MWI method, which employs a short repetition time adiabatic inversion recovery (STAIR) technique in combination with a commonly used fast spin echo (FSE) sequence and provides quantification of myelin water (MW) fractions. Method: Whole-brain MWI was performed using the short repetition time adiabatic inversion recovery prepared-fast spin echo (STAIR-FSE) technique on eight healthy volunteers (mean age: 38±14 years, four-males) and seven patients with multiple sclerosis (MS) (mean age: 53.7±8.7 years, two-males) on a 3T clinical magnetic resonance imaging scanner. To facilitate the quantification of apparent myelin water fraction (aMWF), a proton density-weighted FSE was also used during the scans to allow total water imaging. The aMWF measurements of MS lesions and normal-appearing white matter (NAWM) regions in MS patients were compared with those measured in normal white matter (NWM) regions in healthy volunteers. Both the analysis of variance (ANOVA) test and paired comparison were performed for the comparison. Results: The MW in the whole-brain was selectively imaged and quantified using the STAIR-FSE technique in all participants. MS lesions showed much lower signal intensities than NAWM in the STAIR-FSE images. ANOVA analysis revealed a significant difference in the aMWF measurements between the three groups. Moreover, the aMWF measurements in MS lesions were significantly lower than those in both NWM of healthy volunteers and NAWM of MS patients. Lower aMWF measurements in NAWM were also found in comparison with those in NWM. Conclusions: The STAIR-FSE technique is capable of measuring aMWF values for the indirect detection of myelin loss in MS, thus facilitating clinical translation of whole brain MWI and quantification, which show great potential for the detection and evaluation of changes in myelin in the brain of patients with MS for future larger cohort studies.

Tasas de promoción, repitencia y abandono en la Carrera de Especialistas en Reumatología en la Ciudad de Buenos Aires / Specialty training in rheumatology: Promotion, repetition and dropout rates in the city of Buenos Aires

Objetivos: Evaluar la trayectoria de los alumnos de la Carrera de Especialistas en Reumatología y determinar factores asociados al resultado en el posgrado. Métodos: Análisis retrospectivo (2009-2016). Se determinaron las tasas de promoción, la repitencia y el abandono. Se realizaron análisis multivariados para determinar variables asociadas al éxito académico. Resultados: Sobre 119 alumnos, la promoción efectiva fue del 66,4%, la repitencia sin retraso fue del 14,3%, la repitencia con retraso fue del 11,8% y el abandono fue del 7,6%. La promoción efectiva de la residencia fue del 82,5% vs el 48,2% en el resto (p<0,001), la repitencia con retraso fue del 3,2% vs el 21,4% en el resto (p=0,005) y el abandono fue del 3,2% vs el 12,5% en el resto (p=0,06). El éxito en el posgrado fue mayor a mejor promedio en la carrera de Medicina (OR: 3,41; IC95%: 2,0-6,4; p<0,001). Conclusiones: La residencia se asoció a mayor éxito académico en el posgrado. El puntaje promedio en la cursada de Medicina puede ayudar a identificar a los alumnos en riesgo de fallar.(AU)

Objectives: To evaluate the trajectory of students enrolled in the specialty training in rheumatology. Methods: Retrospective analysis (2009-2016). Promotion, repetition, and dropout rates were determined. Analysis was performed to define variables associated with academic success. Results: Out of 119 students, the actual promotion rate was 66.4%, 11.8% failed an exam (at least) and completed the course after the stipulated time, and the dropout rate was 7.6%. Among residents, the promotion rate was 82.5% vs. 48.2% among the rest (P<.001), the lagging students’ repetition rate was 3.2% vs. 21.4% among the rest (P=.005), and the dropout rate was 3.2% vs. 12.5% among the rest (P=.06). A higher average score in medical school increased the chances of success in the postgraduate programme (OR: 3.41; 95%CI: 2.0-6.4; P<.001). Conclusions: The residency was associated with higher rates of academic success in postgraduate studies. The average score in medical school can help identify students at risk of failure.(AU)

The influence of sex-division, experience, and pacing strategy on performance in the 2020 CrossFit® Open.

To observe workout pacing strategies and determine which best predicted performance, this retrospective study analyzed recorded efforts from a random selection of 160 high-ranking (top 10,000) men and women (n = 80 each) in the 2020 CrossFit® Open (CFO). Video recordings submitted to the official competition leaderboard for all five tests were analyzed to quantify overall test completion rates (and tie-break time for test 5 only) and within-test repetition completion rate (repetitions × sec-1) for each exercise, as well as the quantity of failed repetitions, break strategy (count and duration), and transition times. Each variable was aggregated into first-half, last-half, and total-test averages, slopes, and coefficient of variation; except on test 5 (total-test only). Spearman's rank correlation coefficients were calculated between test completion rates, each test's respective pacing variables, competitor demographics (height and body mass) and CFO experience (i.e., past participation, consecutive competitions, and ranks). Stepwise regression using significantly (p < 0.05) correlated variables produced two prediction models for test performance (best predictor only and best overall model within 8 variables) in a validation group (50% of valid efforts) and then cross-validated against remaining athletes. When no between-group differences were seen, data were combined and used to create the final prediction models for test 1 (r2adj = 0.64-0.96, SEE = 0.4-1.2 repetitions × sec-1), test 2 (r2adj = 0.28-0.85, SEE = 2.0-4.5 repetitions × sec-1), test 3 (r2adj = 0.49-0.81, SEE = 1.1-1.7 repetitions × sec-1), test 4 (r2adj = 0.63-0.78, SEE = 0.6-0.9 repetitions × sec-1), and test 5 (rate: r2adj = 0.71-0.84, SEE = 1.2-1.6 repetitions × sec-1; tie-break time: r2adj = 0.06-0.62, SEE = 1.4-2.3 min). Across the five 2020 CFO tests, the data suggested that repetition pace, breaking strategy, and/or consistency in completing calisthenic-gymnastics components (when prescribed) was most predictive of performance. However, their influence was affected by the complexity of prescribed resistance training exercises and their relative loads. Athletes should prioritize calisthenic-gymnastics components but divert attention to more complex resistance training exercises when prescribed at higher relative intensity loads. Neither previous competition experience nor sex-division altered the hierarchal importance of these considerations.