Trains Of Stimuli Research Articles

Distributional learning of non-native tone contrasts by older adults after training and overnight consolidation

Despite decline in psychoacoustic and statistical learning (SL) abilities, older adults demonstrate remarkably intact perceptual learning in both L2 (tone-word learning) and L1 settings (perceptual adaptation to accented/noise-vocoded speech) but show limited transfer of learning to untrained stimuli. This study tests whether perceptual learning is maintained in an implicit statistical learning task where older adults learn L2 tonal contrasts through exposure to probability distributions of tonal tokens, which may pose higher requirements on both psychoacoustic and SL abilities, and whether sleep-dependent consolidation helps the generalization of perceptual knowledge. L1-Cantonese older adults learned to discriminate a perceptually difficult level-falling tone contrast following a pre-test, training, post- training overnight interval. Training stimuli were synthesized by interpolating naturally produced Mandarin level and high-falling tones into six equidistant steps. Participants either heard a bimodal (two-peak resembling level-falling categories) or unimodal distribution (single-peak) consisting of 256 tokens. ABX discrimination task was administered for testing, with tokens by two genders and on two pseudo-syllables to test generalization. Pilot data of 14 participants showed a trend of group effect with the bimodal group outperforming the unimodal group after training and sleep-dependent consolidation, showing that perceptual learning is maintained in a paradigm that relies heavily on psychoacoustic and SL abilities.

Acoustic divergence from the training sample determines talker identification accuracy for emotional voices

Different emotional states introduce substantial acoustic variations in talkers’ voices. It remains unclear how within-talker variability across emotional states affects listeners' ability to maintain perceptual constancy during talker identification. Here, we investigated (1) how changes in talkers’ emotional state affected talker identification accuracy, (2) how emotional state affected key features of voice acoustics, and (3) how emotion-related changes in these acoustic features affected listeners’ talker identification performance. Forty-eight listeners learned to identify talkers from speech expressing one emotional state (neutral, fearful, or angry) and then attempted to generalize that knowledge to speech expressing another emotional state. Talker identification accuracy was significantly worse in untrained emotions. Changes in voice acoustics across emotions were characterized for mean F0, F0 variability, jitter, HNR, speaking rate, and mean F2. To determine how emotion-related acoustic changes affected talker identification, we modeled talker identification accuracy as a function of difference in these features between training and test stimuli. Accuracy decreased as acoustic differences increased, regardless of talkers’ emotion. Thus, perceptual constancy depends on acoustic similarity to prior experience with a talker’s voice. Larger acoustic deviations, like those introduced by changes in emotional state, are more likely to cause a listener to misidentify a talker.

Optical measurement of glutamate release robustly reports short-term plasticity at a fast central synapse.

Recently developed fluorescent neurotransmitter indicators have enabled direct measurements of neurotransmitter in the synaptic cleft. Precise optical measurements of neurotransmitter release may be used to make inferences about presynaptic function independent of electrophysiological measurements. Here, we express iGluSnFR, a genetically encoded glutamate reporter in mouse spiral ganglion neurons to compare electrophysiological and optical readouts of presynaptic function and short-term synaptic plasticity at the endbulb of Held synapse. We show iGluSnFR robustly and approximately linearly reports glutamate release from the endbulb of Held during synaptic transmission and allows assessment of short-term plasticity during high-frequency train stimuli. Furthermore, we show that iGluSnFR expression slightly alters the time course of spontaneous postsynaptic currents, but is unlikely to impact measurements of evoked synchronous release of many synaptic vesicles. We conclude that monitoring glutamate with optical sensors at fast and large central synapses like the endbulb of Held is feasible and allows robust quantification of some, but not all aspects of glutamate release.

Stimulus variability improves generalization following response inhibition training.

The present study examined the effect of stimulus variability and practice order on generalization to novel stimuli following a single session of response inhibition training. Ninety-six young adults practiced the Go/No-go task online in three training conditions: (1) constant (N = 32)-inhibition practiced on one stimulus; (2) variable-blocked (N = 32)-inhibition practiced on 6 stimuli, each in a separate block; and (3) variable-random (N = 32)-inhibition practiced on 6 stimuli in random order. Generalization was measured by comparing groups on inhibition of novel stimuli and a trained stimulus immediately and 24h after training. Consistent with our hypothesis, the variable-random and the variable-blocked groups showed better generalization to the novel items than the constant group, demonstrating the benefit of stimulus variability. The variable-random group also showed better generalization than the variable-blocked group, demonstrating the benefit of presenting stimuli in random order. Participants' capacity for working memory maintenance was found to modulate the effect of practice order. While the benefit of variability was retained 24h after training, the effect of order was not. Results also show generalization to (1) different type of stimuli using the same task and (2) the same stimuli on a different response inhibition task (the Stop-Signal Task), however, the effect of variable practice and order were not evident in these cases. The study findings illustrate the advantage of using variable stimuli presented in random order for generalization and suggest that these principles of motor learning can be applied to learning of cognitive skills.

Minimal circuit motifs for second-order conditioning in the insect mushroom body.

In well-established first-order conditioning experiments, the concurrence of a sensory cue with reinforcement forms an association, allowing the cue to predict future reinforcement. In the insect mushroom body, a brain region central to learning and memory, such associations are encoded in the synapses between its intrinsic and output neurons. This process is mediated by the activity of dopaminergic neurons that encode reinforcement signals. In second-order conditioning, a new sensory cue is paired with an already established one that presumably activates dopaminergic neurons due to its predictive power of the reinforcement. We explored minimal circuit motifs in the mushroom body for their ability to support second-order conditioning using mechanistic models. We found that dopaminergic neurons can either be activated directly by the mushroom body's intrinsic neurons or via feedback from the output neurons via several pathways. We demonstrated that the circuit motifs differ in their computational efficiency and robustness. Beyond previous research, we suggest an additional motif that relies on feedforward input of the mushroom body intrinsic neurons to dopaminergic neurons as a promising candidate for experimental evaluation. It differentiates well between trained and novel stimuli, demonstrating robust performance across a range of model parameters.

Neural field theory of adaptive effects on auditory evoked responses and mismatch negativity in multifrequency stimulus sequences.

Physiologically based neural field theory (NFT) of the corticothalamic system, including adaptation, is used to calculate the responses evoked by trains of auditory stimuli that differ in frequency. In oddball paradigms, fully distinguishable frequencies lead to different standard (common stimulus) and deviant (rare stimulus) responses; the signal obtained by subtracting the standard response from the deviant is termed the mismatch negativity (MMN). In this analysis, deviant responses are found to correspond to unadapted cortex, whereas the part of auditory cortex that processes the standard stimuli adapts over several stimulus presentations until the final standard response form is achieved. No higher-order memory processes are invoked. In multifrequency experiments, the deviant response approaches the standard one as the deviant frequency approaches that of the standard and analytic criteria for this effect to be obtained. It is shown that these criteria can also be used to understand adaptation in random tone sequences. A method of probing MMNs and adaptation in random tone sequences is suggested to makes more use of such data.

Discrimination training affects stimulus generalization in mice during Pavlovian eyeblink conditioning.

The delicate balance between discrimination and generalization of responses is crucial for survival in our ever-changing environment. In particular, it is important to understand how stimulus discrimination affects the level of stimulus generalization. For example, when we use non-differential training for Pavlovian eyeblink conditioning to investigate generalization of cerebellar-related eyelid motor responses, we find generalization effects on amount, amplitude and timing of the conditioned responses. However, it is unknown what the generalization effects are following differential training. We trained mice to close their eyelids to a 10 kHz tone with an air-puff as the reinforcing stimulus (CS+), while alternatingly exposing them to a tone frequency of either 4 kHz, 9 kHz or 9.5 kHz without the air-puff (CS-) during the training blocks. We tested the generalization effects during the expression of the responses after the training period with tones ranging from 2 kHz to 20 kHz. Our results show that the level of generalization tended to positively correlate with the difference between the CS+ and the CS- training stimuli. These effects of generalization were found for the probability, amplitude but not for the timing of the conditioned eyelid responses. These data indicate the specificity of the generalization effects following differential versus non-differential training, highlighting the relevance of discrimination learning for stimulus generalization.

Estimating Time and Rhythm byPredicting External Stimuli.

In this chapter, we present recent findings from our group showing that elapsed time, interval timing, and rhythm maintenance might be achieved by the well-known ability of the brain to predict the future states of the world. The difference between predictions and actual sensory evidence is used to generate perceptual and behavioral adjustments that help subjects achieve desired behavioral goals. Concretely, we show that (1) accumulating prediction errors is a plausible strategy humans could use to determine whether a train of consecutive stimuli arrives at regular or irregular intervals. By analyzing the behavior of human and non-human primate subjects performing rhythm perception tasks, we demonstrate that (2) the ability to estimate elapsed time and internally maintain rhythms is shared across primates and humans. Neurophysiological recordings show that (3) the medial premotor cortex engages in rhythm entrainment and maintains oscillatory activity that reveals an internal metronome's spatial and temporal characteristics. Finally, we demonstrate that (4) the amplitude of gamma oscillations within this cortex increases proportionally to the total elapsed time. In conjunction with our most recent experiments, our results suggest that timing might be achieved by an internal simulation of the sensory stimuli and the motor commands that define the timing task that needs to be performed.

RECUPERAÇÃO ENTRE SÉRIES NO TREINO DE FORÇA: REVISÃO SISTEMÁTICA E META-ANALISE

ABSTRACT Introduction: The recovery interval (RI) between sets and exercises has received attention from strength training (ST) researchers, to understand the relationship of rest on performance maintenance, especially the total load in a training session. It is known that each individual responds in a specific way to the training stimulus. So, what would be the effect of the different recovery interval strategies on the strength performance? Objective: Compare the different recovery intervals in strength training volume, considering the number of repetitions in healthy adults. Methods: We conducted a systematic review and meta-analysis based on methodological criteria, comparing fixed and self-selected RI on training volume, identified by the number of repetitions performed in a weight training program. Three electronic databases (Pubmed, VHL Virtual Health Library, Ebsco Sportdiscus) were analyzed, combining the expressions “resistance training”, “resistance exercise”, “strength exercise”, “recovery interval”, “rest interval”, “interval auto suggested”, “auto range selected” with “AND” and “OR” combination. Results: Pooled data from five studies showed a large significant effect in favor of the experimental group (>2 minutes) (MD: 1.24; 95%-CI [0.78; 1.71]; z: 5.25, Q:1.08; p < 0.01), since in the studies, recovery interval allowed a greater training volume. Conclusion: Longer RI seems be better, for maintaining total training volume, although there is no consensus for different training objectives against the self-selected RI. Thus, we imagine that this strategy may be important in the organizing a bodybuilding exercise program. Level of Evidence I; Systematic Review and Meta Analysis.

Music influences performance without increasing perceived exertion during high-intensity rowing intervals: a cross-over design study.

This study assessed how exposure to slow (SBM) versus fast beat music (FBM) during high-intensity rowing intervals affects performance, heart rate (HR), lactate levels, relative perceived exertion (RPE), and recovery. The A/B crossover design involved 21 participants performing 5 × 500 m rowing intervals under two conditions: FBM and SBM. Primary endpoint was the difference in total rowing time. Secondary endpoints included average HR, average RPE as well as rowing interval times, RPE, and HR per interval. For exploratory purpose, HR and lactate drop during the initial 5 min post completion was analyzed. Listening to FBM resulted in significantly shorter total rowing times (p = 0.009, rB = 0.59), especially during the 1st interval. The 1st interval was also significantly faster than intervals 2-5 (p < 0.001), with the greatest performance drop between the 1st and 2nd interval during FBM. Average HR was significantly lower when listening to SBM (p = 0.03, rB = 0.48), while average RPE showed no significant difference (p = 0.47, rB = 0.02). Lactate values after interval 5 were significantly lower in SBM (p = 0.05, rB = 0.41), but no significant difference was found for lactate drop (p = 0.21, rB = 0.21). However, participants exhibited a higher HR drop rate with SBM (p = 0.05, rB = 0.42). FBM improved performance without increasing RPE, while SBM proved superior for recovery. Systematic customization of music based on intended training stimuli holds broad potential for the competitive sports, fitness, and health sector.

Facial nerve electrical motor evoked potential in cerebellopontine angle tumors for its anatomical and functional preservation.

Among the technical measures to preserve facial nerve (FN) function, intraoperative neuromonitoring has become mandatory and is constantly being scrutinized. Hence, to determine the efficacy of FN motor evoked potentials (FNMEPs) in predicting long-term motor FN function following cerebellopontine angle (CPA) tumor surgery, an analysis of cases was done. In 37 patients who underwent CPA surgery, FNMEPs through corkscrew electrodes positioned at C5-C6 and C6-C5 (C is the central line of the brain as per 10-20 EEG electrode placement) were used to deliver short train stimuli and recorded from the orbicularis oculi, oris, and mentalis muscles. In 58 patients, triggered electromyography (EMG) was able to identify the FN during resection of tumor, but 8 out of these (4.64%) patients developed new facial weakness, whereas 3 out of 38 (1.11%) patients who had intact FN function MEP (decrement of FN target muscles - CMAPs amplitude peak to peak >50-60%), developed new facial weakness (House and Brackmann grade II to III). The FNMEP has significant superiority over triggered EMG when tumor is giant and envelops the FN.

Analysis of Errors Following SCVTr Treatment: An Indicator for Improved Lexical Retrieval Abilities in Persons with Aphasia

Purpose: Error analysis technique aids in understanding the psycholinguistic mechanisms associated with word retrieval. In addition to the linguistic test scores, if authors document the change in errors following treatment it may give better insight into the prognosis of PWAs. Despite the significance of error analysis, most of the study results elucidate the improvement merely in assessing the accuracy of naming skills. Thus, the present study was designed to assess the error patterns following treatment.Methods: A total of 11 PWAs (fluent and non-fluent aphasia) were enrolled for the study, these participant’s average age was 38.72 years (Range=24-64, SD=11.97). SCVTr treatment was rendered; in this treatment, PWAs were presented with 10 targeted verbs with a range of minimal (broad cues) and maximal cues (narrower cues) based on the success of the retrieval minimal to maximal cues were presented. The verbatim of trained and untrained stimuli (probes) of pre-treatment phase, post-treatment phase, and follow-up phase were subjected to error analysis using Edmonds and Babb (2011) protocol.Conclusions: The error patterns of individual participants across pre and post-treatment phases showed alleviated scores in the post-treatment phase among all the participants. Furthermore, all the participants exhibited almost identical error score patterns in the follow-up phase as in the post-treatment phase. The error analysis technique is the most powerful tool to track the changes at the psycholinguistic level.

Different neural mechanisms for nonsalient trained stimuli and physically salient stimuli in visual processing.

Previous studies have shown that nonsalient trained stimuli could capture attention and would be actively suppressed when served as distractors. However, it was unclear whether nonsalient trained stimuli and physically salient stimuli operate through the same attentional neural mechanism. In the current study, we investigated this question by recording event-related potentials (ERPs) of searching for the two stimuli separately after matching the difficulty. The present results provided additional evidence for the function of the suppression in that it may terminate a shift of attention. For the N1 component, the nonsalient trained stimuli had a shorter latency and larger amplitude than the physically salient stimuli whether presented as targets or distractors. It indicated that the nonsalient trained stimuli had an earlier sensory processing and greater visual attention orienting. The N2 posterior-contralateral (N2pc) amplitude of the physically salient target was larger than the nonsalient trained target. This suggested that physically salient stimuli had a stronger ability to capture attention. However, when they presented as distractors, only the nonsalient trained stimuli could elicit the PD component. Therefore, active suppression of the physically salient stimuli was more difficult than the nonsalient trained stimulus with the same difficulty. For the P3 component, the amplitude of the physically salient stimuli was larger than that of the nonsalient trained stimuli, both as targets and distractors, which indicated that the top-down controlled process of outcome evaluation for the salient triangle was stronger. Overall, these results suggested that they were processed via different neural mechanisms in the early sensory processing, attentional selection, active suppression, and the outcome-evaluation process.

Cerebellar Direct Current Stimulation Reveals the Causal Role of the Cerebellum in Temporal Prediction.

Temporal prediction (TP) influences our perception and cognition. The cerebellum could mediate this multi-level ability in a context-dependent manner. We tested whether a modulation of the cerebellar neural activity, induced by transcranial Direct Current Stimulation (tDCS), changed the TP ability according to the temporal features of the context and the duration of target interval. Fifteen healthy participants received anodal, cathodal, and sham tDCS (15min × 2mA intensity) over the right cerebellar hemisphere during a TP task. We recorded reaction times (RTs) to a target during the task in two contextual conditions of temporal anticipation: rhythmic (i.e., interstimulus intervals (ISIs) were constant) and single-interval condition (i.e., the estimation of the timing of the target was based on the prior exposure of the train of stimuli). Two ISIs durations were explored: 600ms (short trials) and 900ms (long trials). Cathodal tDCS improved the performance during the TP task (shorter RTs) specifically in the rhythmic condition only for the short trials and in the single-interval condition only for the long trials. Our results suggest that the inhibition of cerebellar activity induced a different improvement in the TP ability according to the temporal features of the context. In the rhythmic context, the cerebellum could integrate the temporal estimation with the anticipatory motor responses critically for the short target interval. In the single-interval context, for the long trials, the cerebellum could play a main role in integrating representation of time interval in memory with the elapsed time providing an accurate temporal prediction.

Pre-sleep protein supplementation does not improve performance, body composition, and recovery in British Army recruits (part 1).

Dietary protein is crucial for optimising physical training adaptations such as muscular strength and mass, which are key aims for athletic populations, including British Army recruits. New recruits fail to meet the recommended protein intake during basic training (BT), with negligible amounts consumed in the evening. This study assessed the influence of a daily bolus of protein prior to sleep on performance adaptations, body composition and recovery in British Army recruits. 99 men and 23 women [mean ± standard deviation (SD): age: 21.3 ± 3.5 years, height: 174.8 ± 8.4 cm, body mass 75.4 ± 12.2 kg] were randomised into a dietary control (CON), carbohydrate placebo (PLA), moderate (20 g) protein (MOD) or high (60 g) protein (HIGH) supplementation group. Supplements were isocaloric and were consumed on weekday evenings between 2000 and 2100 for 12 weeks during BT. Performance tests (mid-thigh pull, medicine ball throw, 2 km run time, maximal push-up, and maximal vertical jump) and body composition were assessed at the start and end of BT. Dietary intake, energy expenditure, salivary hormones, urinary nitrogen balance, perceived muscle soreness, rating of perceived exertion, mood, and fatigue were assessed at the start, middle and end of BT. Protein supplementation increased protein intake in HIGH (2.16 ± 0.50 g⸱kg-1⸱day-1) and MOD (1.71 ± 0.48 g⸱kg-1⸱day-1) compared to CON (1.17 ± 0.24 g⸱kg-1⸱day-1) and PLA (1.31 ± 0.29 g⸱kg-1⸱day-1; p < 0.001). Despite this, there was no impact of supplementation on mid-thigh pull performance (CON = 7 ± 19%, PLA = 7 ± 19%, MOD = 0 ± 16%, and HIGH = 4 ± 14%; p = 0.554) or any other performance measures (p > 0.05). Fat-free mass changes were also similar between groups (CON = 4 ± 3%, PLA = 4 ± 4%, MOD = 3 ± 3%, HIGH = 5 ± 4%, p = 0.959). There was no impact of protein supplementation on any other body composition or recovery measure. We conclude no benefits of pre-bed protein supplementation to improve performance, body composition and recovery during BT. It is possible the training stimulus was great enough, limiting the impact of protein supplementation. However, the high degree of inter-participant variability suggests an individualised use of protein supplementation should be explored, particularly in those who consume sub-optimal (<1.6 g⸱kg-1⸱day-1) habitual amounts of protein. Clinical trial registration: The study was registered with ClinicalTrials.gov, U.S. national institutes (identifier: NCT05998590).

Glucocorticoids modulate neural activity via a rapid non-genomic effect on Kv2.2 channels in the central nervous system

Glucocorticoids are primary stress hormones that exert neuronal effects via both genomic and non-genomic signaling pathways. However, their rapid non-genomic effects and underlying mechanisms on neural activities remain elusive. In the present study, we investigated the rapid non-genomic effect of glucocorticoids on Kv2.2 channels in cultured HEK293 cells and acute brain slices including cortical pyramidal neurons and calyx-type synapses in the brain stem. We found that cortisol, the endogenous glucocorticoids, rapidly increased Kv2.2 currents by increasing the single-channel open probability in Kv2.2-expressing HEK293 cells through activation of the membrane-associated glucocorticoid receptor. Bovine serum albumin-conjugated dexamethasone, a membrane-impermeable agonist of the glucocorticoid receptor, could mimic the effect of cortisol on Kv2.2 channels. The cortisol-increased Kv2.2 currents were induced by activation of the extracellular signal-regulated protein kinase (ERK) 1/2 kinase, which could be inhibited by U0126, an antagonist of the ERK signaling pathway. In layer 2 cortical pyramidal neurons and the calyx of Held synapses, cortisol suppressed the action potential firing frequency during depolarization and reduced the successful rate upon high-frequency stimulation by activating Kv2.2 channels. We further examined the postsynaptic responses and found that cortisol did not affect the mEPSC and evoked EPSC, but increased the activity-dependent synaptic depression induced by a high-frequency stimulus train. In conclusion, glucocorticoids can rapidly activate Kv2.2 channels through membrane-associated glucocorticoid receptors via the ERK1/2 signaling pathway, suppress presynaptic action potential firing, and inhibit synaptic transmission and plasticity. This may be a universal mechanism of the glucocorticoid-induced non-genomic effects in the central nervous system.

Comparison of Different Coach Competition Micro-Cycle Planning Strategies in Professional Soccer

Background: Coaches propose training strategies to develop their playing model, but the impact on the conditional demand of players is unknown. The objective of this study aimed to assess the conditional demands associated with five competitive micro-cycle (Mi) planning strategies put forth by professional soccer coaches. The dependent locomotor variables were: total distance traveled (TD, in m), high-speed running distance (TD21, &gt;21 km·h−1, in m), sprint distance (TD27, &gt;27 km·h−1, in m), acceleration load (aLoaD, in AU) and number of accelerations (ACC2, &gt;2 m·s−2 in n) and decelerations (DEC2, &lt;−2 m·s−2 in n). The activity profile of the players was monitored during each training session using a global positioning system (GPS) during four seasons (2018–2019 to 2021–2022). Regardless of the coach, the sessions furthest from Mi (MD+1, MD-4 and MD-3) were the most conditionally demanding, where TD27 was especially stimulated on MD-3 (ES = 0.7, 0.2/1.2, mean and range; p &lt; 0.05); furthermore, MD-2 was the least demanding session of all the trainers (ES = −2.4, −2.6/−1.5, mean and range; p &lt; 0.01). However, there were nuances regarding the conditional demand among the coaches: Co1 and Co2 proposed a higher conditional demand in the MD-2 and MD-1 sessions (p &lt; 0.05). The conclusion was twofold: elite soccer coaches proposed a horizontal alternation in the weekly distribution of training stimuli; nevertheless, the differences in the style of play of each coach affected the week-planning strategy.

Sensory event-related potential morphology predicts age in premature infants

ObjectiveWe investigated whether sensory-evoked cortical potentials could be used to estimate the age of an infant. Such a model could be used to identify infants who deviate from normal neurodevelopment. MethodsInfants aged between 28- and 40-weeks post-menstrual age (PMA) (166 recording sessions in 96 infants) received trains of visual and tactile stimuli. Neurodynamic response functions for each stimulus were derived using principal component analysis and a machine learning model trained and validated to predict infant age. ResultsPMA could be predicted accurately from the magnitude of the evoked responses (training set mean absolute error and 95% confidence intervals: 1.41 [1.14; 1.74] weeks,p = 0.0001; test set mean absolute error: 1.55 [1.21; 1.95] weeks,p = 0.0002). Moreover, we show that their predicted age (their brain age) is correlated with a measure known to relate to maturity of the nervous system and is linked to long-term neurodevelopment. ConclusionsSensory-evoked potentials are predictive of age in premature infants and brain age deviations are related to biologically and clinically meaningful individual differences in nervous system maturation. SignificanceThis model could be used to detect abnormal development of infants’ response to sensory stimuli in their environment and may be predictive of neurodevelopmental outcome.

Assessing the Use of Heart-Rate Monitoring for Competitive Swimmers.

Quantifying training intensity provides a comprehensive understanding of the training stimulus. Recent technological advances may have improved the feasibility of using heart-rate (HR) monitoring in swimming. However, the implementation of HR monitoring is yet to be assessed longitudinally in the daily training environment of swimmers. This study aimed to assess the implementation of HR by comparing the training-intensity distribution from an external measure, planned volume at set intensities (PVSI), with the internal training-intensity distribution measured using time in HR zones. Using a longitudinal observational design, 10 competitive swimmers (8 male and 2 female, age: 22.0 [2.3]y, Fédération Internationale de Natation point score: 842.9 [58.5], mean [SD]) were monitored daily for 6months. Each session, HR data, and coached-planned and athlete-reported session rating of perceived exertion (Modified Category Ratio 10 scale) were recorded. Based on previously determined training zones from an incremental step test, PVSI was calculated using the planned distance and planned intensity of each swim bout. Training-intensity distributions were analyzed using a linear mixed model (lme4). The model revealed a small to moderate relationship between PVSI and time in HR zone, based on the Nakagawa R-squared value (range .14-.42). Training-intensity distribution differed between the internal measure (ie,HR) and the external measure of intensity (ie,PVSI). This demonstrates that internal and planned external measures of intensity cannot be used interchangeably to monitor training. Further research should explore how to best integrate these measures to better understand training in swimming.

Data-driven multiscale model of macaque auditory thalamocortical circuits reproduces in vivo dynamics

We developed a detailed model of macaque auditory thalamocortical circuits, including primary auditory cortex (A1), medial geniculate body (MGB), and thalamic reticular nucleus, utilizing the NEURON simulator and NetPyNE tool. The A1 model simulates a cortical column with over 12,000 neurons and 25 million synapses, incorporating data on cell-type-specific neuron densities, morphology, and connectivity across six cortical layers. It is reciprocally connected to the MGB thalamus, which includes interneurons and core and matrix-layer-specific projections to A1. The model simulates multiscale measures, including physiological firing rates, local field potentials (LFPs), current source densities (CSDs), and electroencephalography (EEG) signals. Laminar CSD patterns, during spontaneous activity and in response to broadband noise stimulus trains, mirror experimental findings. Physiological oscillations emerge spontaneously across frequency bands comparable to those recorded invivo. We elucidate population-specific contributions to observed oscillation events and relate them to firing and presynaptic input patterns. The model offers a quantitative theoretical framework to integrate and interpret experimental data and predict its underlying cellular and circuit mechanisms.