Brain Sciences

Changes in the corticospinal (CSE) and cortico-cortical (CCE) excitability of the primary motor cortex (M1) may underlie the effect of mental fatigue on physical performance. To date, research on this subject has predominantly focused on the examination of CSE, with limited exploration of effects of mental fatigue on CCE. This study aims to investigate the influence of mental fatigue induced through prolonged cognitive activity on both CSE and CCE. Fifteen healthy adults (aged 29.13{+/-}7.15 years) participated in assessments of CSE (Motor evoked potential - MEP amplitude) and CCE (Intracortical facilitation - ICF, short-interval intracortical inhibition - SICI, and long-interval intracortical inhibition - LICI) before and after a 60-minute Stroop task (experimental condition) or watching a documentary (control condition). Subjective mental fatigue was measured using the mental fatigue visual analogue scale (M-VAS), and workload associated with the tasks was assessed using the National Aeronautics and Space Administration (NASA) task load index. Objective mental fatigue was defined by the time-related decline in Stroop task performance. The study results revealed no significant differences in M-VAS, CSE and CCE between the two conditions. Stroop task performance did not exhibit significant changes over time. However, participants perceived the Stroop task to be more mentally demanding and effortful than watching the documentary (p<0.05). Further analysis of Stroop task performance at individual participants level identified two sub-groups of participants: one exhibiting deteriorating performance with time (fatigued subgroup) and the other showing improved performance (non-fatigued subgroup). Descriptively, cortical inhibition increased (reduced SICI and ICF values) from pre to post Stroop task in the fatigued subgroup, while the non-fatigued group displayed an opposite pattern. The findings suggest that mental fatigue may lead to increased cortical inhibition, highlighting the need for further investigation with a larger sample size.

BackgroundPeople living with HIV (PLWHA) smoke at three times the rate of the general population and respond poorly to cessation strategies. Previous studies examined transcranial magnetic stimulation (TMS) over left dorsolateral prefrontal cortex (L. dlPFC) to reduce craving, but no studies have explored TMS among PLWHA who smoke. The current pilot study compared the effects of active and sham intermittent theta-burst stimulation (iTBS) on resting state functional connectivity (rsFC), cigarette cue attentional bias, and cigarette craving in PLWHA who smoke. MethodsEight PLWHA were recruited (single-blind, within-subject design) to receive one session of iTBS (n=8) over the L. dlPFC using neuronavigation and, four weeks later, sham iTBS (n=5). Cigarette craving and attentional bias assessments were completed before and after both iTBS and sham iTBS. rsFC was assessed before iTBS (baseline) and after iTBS and sham iTBS. ResultsCompared to sham iTBS, iTBS enhanced rsFC between the L. dlPFC and bilateral medial prefrontal cortex and pons. iTBS also enhanced rsFC between the right insula and right occipital cortex compared to sham iTBS. iTBS also decreased cigarette craving and cigarette cue attentional bias. ConclusioniTBS could potentially offer a therapeutic option for smoking cessation in PLWHA.

Behavioral evidence suggests that engaging with fiction is positively correlated with social abilities. The rationale behind this link is that engaging with fiction and fictional characters may offer a training mode for mentalizing and empathizing with sentient agents in the real world, analogous to a flight simulator for pilots. In this study, we explored the relationship between reading fiction and mentalizing by looking at brain network dynamics in 57 participants who varied on how much fiction they read in their daily lives. The hypothesis was that if reading fiction indeed trains mentalizing, a task that requires mentalizing -Like immersing in a fictional story and engaging with a protagonist-should elicit differences in brain network dynamics depending on how much people read. More specifically, more frequent readers should show increased connectivity within the theory of mind network (ToM) or between the ToM network and other brain networks. While brain activation was measured with fMRI, participants listened to two literary narratives. We computed time-course correlations between brain regions and compared the correlation values from listening to narratives to listening to an auditory baseline condition. The between-region correlations were then related to individual differences measures including the amount of fiction that participants consume in their daily lives. Our results show that there is a linear relationship between how much people read and the functional connectivity in areas known to be involved in language and mentalizing. This adds neurobiological credibility to the fiction influences mentalizing abilities hypothesis as suggested on the basis of conceptual analysis.

This study is a retrospective chart review of 200 clients who participated in a non-verbal restorative Cognitive Remediation Training (rCRT) program. The program was applied to effect proper neural functional remodeling needed to support resilient, flexible and adaptable behaviors after encountering a mild to medium closed head traumatic brain injury (mTBI). The r CRT training program focused on improving functional performance in executive cognitive control networks as defined by fMRI studies. All rCRT training activities were delivered in a semi-game-like manner, incorporating a Brain Computer Interface (BCI) that provided in-the-moment neural network performance integrity metrics (nPIMs) used to adjust the level of play required to properly engage long-term potentiation (LTP) and long term depreciation (LTD) network learning rules. This study reports on t-test and Reliable Change Index (RCI) changes found within cognitive abilities performance metrics derived from the Woodcock Johnson Cognitive Abilities III Test. We compared pre and post scores from seven cognitive abilities considered dependent on executive cognitive control networks against seven non-executive control abilities. We observed significant improvements (p values 10 to 10-22) with large Cohens d effect sizes (0.78-1.20) across thirteen cognitive ability domains with a medium effect size (.49) on the remaining. The mean percent change for pooled trained domain was double that observed for pooled untrained domain, at 17.2% versus 8.3%, respectively. To further adjust for practice effects, practice effect RCI values were computed and further supported the effectiveness of the rCRT training (RCI-trained 1.4 - 4.8; untrained RCI 0.08-0.75).

BackgroundFetal Alcohol Spectrum Disorders (FASD) describes a spectrum of ethanol-induced neural and facial developmental defects. Ethanol susceptibility is modulated by genetics, but their underlying mechanisms remain poorly understood. In all vertebrates, a series of complex cellular events give rise to the body plan, including convergence & extension (C&E) and endoderm/ cranial neural crest (CNC-which gives rise to the facial skeleton) morphogenesis. These events are critical to establish complex signaling interactions, driving embryo development, including the facial skeleton. In zebrafish, C&E occurs between 6-10 hpf while endoderm/CNC morphogenesis occurs 10-24 hpf. Previous work shows that the PCP mutants are sensitive to ethanol from 6-24 hpf, covering both C&E and endoderm/CNC morphogenesis and exhibiting multiple defects to the forming head raising the question whether ethanol during both time windows drives PCP-ethanol defects. We hypothesize that PCP single and double mutants are ethanol sensitive 10-24 hpf, after C&E. We also hypothesize BMP signaling (sensitive 10-18 hpf) interacts with and sensitizes the PCP pathway to ethanol. MethodsHere, we treated PCP/BMP mutants with ethanol from 6-10, 10-18, 10-24 or 24-30 hpf and combined morphometric and linear measurements to examine facial development. ResultsWe show that PCP mutant larvae are ethanol-sensitive from 10-24 hpf, but not 6-10 or 24-30 hpf. We also show that BMP mutants sensitize PCP mutants to ethanol and lead to novel ethanol-independent midline craniofacial defects. Our results suggest that the ethanol-sensitive role of PCP pathway occurs after C&E, during endoderm/CNC morphogenesis and that the PCP and BMP pathways genetically interact during the morphogenesis events. ConclusionsUltimately, our work builds on a mechanistic paradigm of ethanol-induced birth defects we have been developing, connecting conceptual framework with concrete cellular events that could be ethanol-sensitive beyond facial development.

Tobacco-related deaths exceed those resulting from homicides, suicides, motor vehicle accidence, alcohol consumption, illicit substance use, and acquired immunodeficiency syndrome (AIDS), combined. Amongst U.S. veterans, this trend is particularly concerning given that those suffering from posttraumatic stress disorder (PTSD)--about 11% of those receiving care from the Department of Veterans Affairs (VA)--have triple the risk of developing tobacco use disorder (TUD). The most efficacious strategies being used at the VA for smoking cessation only result in a 23% abstinence rate, and veterans with PTSD only achieve a 4.5% abstinence rate. Therefore, there is a critical need to develop more effective treatments for smoking cessation. Recent studies have revealed the insula as integrally involved in the neurocircuitry of TUD, specifically showing that individuals with brain lesions involving this region had drastically improved quit rates. Some of these studies show a probability of quitting up to 5 times greater compared to non-insula lesioned regions). Altered activity of the insula may be involved in the disruption of the salience networks (SN) connectivity to the executive control network (ECN), which compromises that patients ability to switch between interoceptive states focused on cravings to executive and cognitive control. Thus, we propose a feasibility phase II randomized controlled trial (RCT) to study a patterned form of repetitive transcranial magnetic stimulation (rTMS), intermittent theta burst stimulation (iTBS), at 90% of the subjects resting motor threshold (rMT) applied over a region in the right post-central gyrus most functionally connected to the right posterior insula. We hypothesize that by increasing functional connectivity between the SN with the ECN to enhance executive control and by decreasing connectivity with the default mode network (DMN) to reduce interoceptive focus on withdrawal symptoms, we will improve smoking cessation outcomes. Fifty eligible veterans with comorbid TUD and PTSD will be randomly assigned to two conditions: active-iTBS + cognitive behavioral therapy (CBT) + nicotine replacement therapy (NRT) (n=25) or sham-iTBS + CBT + NRT (n=25). The primary outcome, feasibility, will be determined by achieving a recruitment of 50 participants and retention rate of 80%. The success of iTBS will be evaluated through self-reported nicotine use, cravings, withdrawal symptoms, and abstinence following quit date (confirmed by bioverification) along with evaluation for target engagement through neuroimaging changes, specifically connectivity differences between the insula and other regions of interest.

Background and aimsIncreasing popularity of Internet has exposed our children pornography addiction. As in other types of addiction, it affects a brain region known as prefrontal cortex (PFC), which is important in executive functions and inhibitory control. However, this region was loosely defined, and there was no consensus for that definition. We aimed to use volumetric MRI in finding the defining region of PFC which would be suitable in distinguishing pornography addicted juveniles. MethodsWe enrolled 30 juveniles (12-16 y.o.) consisting of 15 pornography addiction and 15 non-addiction subjects. We proposed several models of PFC definition from mix-and-matched subregions, consisting of orbitofrontal (OFC), inferior frontal gyrus (IFG; pars orbitalis, opercularis, and triangularis), dorsolateral PFC (DLPFC), and anterior cingulate (ACC). Suitable PFC definition was defined as models which volume statistically different between both groups. Brain volumetric was measured using 3D-T1 3T MRI images and analyzed using FreeSurfer(R) for automatic cortical reconstruction and brain segmentation (recon-all command). ResultsWe found significant differences between groups in 6 models, which mainly included OFC, ACC, and DLPFC, with models devoid of DLPFC had lowest mean differences. ConclusionThe most suitable definition of PFC for pornography addiction study should consist of OFC, ACC, and especially DLPFC. Inferior frontal gyrus pars orbitalis was not necessary for this purpose, but may increase effect size if it is included.

Video gaming often sparks controversy, though negative effects are mainly linked to gaming disorder, not gaming itself. Research shows that gaming disorder is associated with reduced executive functioning and greater reliance on habitual processes, while recreational gaming may relate to enhanced cognitive functions. However, comprehensive comparisons of cognitive profiles across gaming behaviors remain scarce. Therefore, we aimed to compare the cognitive functioning of non-gamers (NG), recreational gamers (RG), and gaming disorder risk individuals (GDR). Based on the Internet Gaming Disorder Test scores, 114 participants were classified into NG, RG, or GDR groups. Executive functions were assessed using the Go/No-Go, Counting Span, Digit Span, Card Sorting, 1-back and 2-back tasks. Habit learning was measured with the Alternating Serial Reaction Time task. The GDR group showed reduced working memory, performing worse on the Digit Span task than the NG group, and worse on the Counting Span task than both NG and RG groups. Conversely, the RG group displayed enhanced attention-related performance. No group differences emerged in other executive functions or overall habit learning. Interaction analyses revealed a negative relationship between habit learning and inhibitory control/updating across groups, supporting competition theory, while a positive link between working memory and habit learning in NG and GDR groups suggests possible compensatory mechanisms. Overall, this study underscores that cognitive impairments are linked to gaming disorder rather than gaming itself, while recreational gaming may offer cognitive benefits. These findings provide insights into the distinct cognitive profiles of recreational gamers and those at risk of gaming disorder. HighlightsO_LICognitive profiles differ for gaming disorder vs. recreational gaming. C_LIO_LIWorking memory is impaired in individuals at risk of gaming disorder. C_LIO_LIRecreational gaming is linked to enhanced attention-related performance. C_LIO_LIExecutive functions and habits compete with each other, regardless of gaming. C_LIO_LICognitive systems show both competitive and compensatory links. C_LI

To contribute to the understanding of changes in the factors governing the development of neural connectivity, the developmental structure of EEG coherence in adolescents and young adults was analyzed using the means, variances, and covariances of high alpha frequency band coherence measures from a set of 27 coherence pairs obtained from a sample of 1426 participants from the COGA study with 5006 observations over ages 12 through 31. Means and covariances were calculated at 96 age centers by a LOESS method. In the current study, trajectories of covariance matrices considered as individual units were determined by tensorial analysis: calculation of Riemannian geodesic (non-Euclidean) distances between matrices and application of both linear and non-linear dimension reduction techniques to these distances. Results were evaluated by bootstrap methods. Mean coherence trajectories for males and females were very similar, showing a steady upward trend from ages 12 to 20 which diminishes gradually from 20 to 25 and reaches stability from 25 to 31. In contrast, the individual covariance trajectories of males and female differed, with the male covariance levels becoming greater than that of females during the developmental process. Tensorial determination of the distances from the initial covariance matrix of subsequent covariance matrices to age 20 had the same trajectory as the mean coherence values. Tensorial determination of the trajectories of the covariance matrices of males and females based on their all pairs geodesic distances revealed a non-linear pattern in the multi-dimensional space of each of the trajectories: A steady increase in one dimension is accompanied by deviations from it peaking at age 20 which have both transient and lasting effects. There is a precise temporal parallelism of this pattern of covariance in males and females, while there is a consistent distance between the male and female covariance structures throughout the developmental process. Between region differences (anterior-posterior) within each sex are greater than between sex differences within regions. Examining development using multiple methods provides unique insight into the developmental process.

As the relevance of neuroscience in education grows, effective methods for teaching this complex subject in high school classrooms remain elusive. Integrating classroom experiments with brain-based robots offers a promising solution. This paper presents a structured curriculum designed around the use of camera-equipped mobile robots which enables students to construct and explore artificial neural networks. Through this hands-on approach, students engage directly with core concepts in neuroscience, learning to model spiking neural networks, decision-making processes in the basal ganglia, and principles of learning and memory. The curriculum not only makes challenging neuroscience concepts accessible and engaging but also demonstrates significant improvements in students understanding and self-efficacy. By detailing the curriculums development, implementation, and educational outcomes, this study outlines a scalable model for incorporating advanced scientific topics into secondary education, paving the way for a deeper student understanding of both theoretical neuroscience and its practical applications.

This paper focused on determining the asymptotical stability of the new model which establishes that a disease-free equilibrium state exists and is locally asymptotically stable when the basic reproduction number 0 [&le;] R0 < 1 and the following threshold conditions (0 [&le;] R1 < 1, 0 [&le;] R2 < 1, 0 [&le;] R3 < 1, 0 [&le;] R4 < 1 and 0 [&le;] R5 < 1, 0 [&le;] R6 < 1, 0 [&le;] R7 < 1, 0 [&le;] R8 < 1) are satisfied. Results from the model analysis shows that the proportion of infected juvenile and adult sub-population in the presence of High Active Anteritroviral Therapy (HAART) drastically reduce to a zero (R0 = 0) as compared to the infected age-structured population when treatment rate is low and the net transmission rate is near zero.

ObjectiveYouth male athletes show changes in resting-state causal brain connectivity following subacute concussion; however, little is known about how concussion alters causal brain connectivity in female youth. In this study, we compared resting-state causal brain connectivity in healthy and subconcussed females. Materials and methodsData from 11 concussed and 15 healthy control female athletes were included in this study. Five minutes of resting state eyes-closed EEG data were collected from all participants. SCAT5 data were also collected from all concussed participants. Causal connectivity was calculated from EEG source data. Network topology was evaluated using the degree assortativity coefficient, a summary statistic describing network structure of information flow between source locations. ResultsWe observed three main results: 1) a qualitative difference in the spatial pattern of the most active connections, marked by posterior connectivity shifting in the concussed group, 2) an increase in the magnitude of connectivity in the concussed group, and 3) no significant difference in degree assortativity between the concussed and control groups. ConclusionCausal connectivity changes following concussion in females do not follow the same trends reported in males. These findings suggest a potential sex difference in injury response and may have implications for recovery.

Injuries to the spinal cord at the cervical level can lead to loss of upper limb function. Recent work suggests that combining functional task practice with Transcutaneous electrical stimulation of the spinal cord (TCES) can increase strength and upper limb function in people living with chronic cervical spinal cord injury (cSCI). Participants (n = 5) were randomly assigned to: Group_1 (n = 3) receiving one month of upper limb task practice (ULTP) followed by one month of upper limb task practice paired with spinal stimulation (ULTP+TCES); Group_2 (n = 2) receiving one month of ULTP+TCES followed by one month of ULTP. Changes in hand function (assessed via the Graded Redefined Assessment of Strength, Sensibility), independence and quality of life were investigated after each intervention and at three-months follow-up. In addition, we assessed cortical (via Transcranial Magnetic Stimulation) and spinal (via single-pulse TCES) excitability at those same time points. For Group_1: improvements in hand function from baseline were observed after ULTP+TCES (p<0.001) and at follow-up (p=0.017); quality of life increased between baseline and after ULTP (p=0.002), ULTP+TCES (p<0.001) and at follow-up (p=0.013); spinal excitability increased from baseline to after ULTP+TCES (p<0.001). For Group_2: improvements in hand function from baseline were observed after ULTP+TCES (p<0.001), ULTP (p<0.001) and at follow-up (p<0.001); corticospinal excitability increased from baseline to after ULTP (p=0.013); spinal excitability increased from baseline to after ULTP+TCES (p<0.001) and the increase persisted 3 months later at follow-up (p=0.04). Our findings demonstrate that non-invasive spinal stimulation paired with task practice can improve hand function more than task practice alone in people living with a cSCI. In addition, we suggest that spinal plasticity induced by spinal stimulation is a potential neural substrate for the attained improvements in hand function.

PurposeBurn injuries affect the central nervous system, and evidence suggests they induce changes in cortical excitability related to motor dysfunction. The current study investigated markers of neuroplasticity in the motor cortex and motor performance in the subacute period following burn injury. MethodsThirty-four patients with a minor burn injury (total body surface area: 1.0 {+/-} 2.0%; 16 females; age: 46.0 {+/-} 14.0 years) participated in a longitudinal study with assessments ranging from [~]1 to [~]17 weeks post-injury. Transcranial magnetic stimulation (TMS) was used to evaluate motor cortex excitability and short- and long-intracortical inhibition (SICI; LICI) before and after application of paired associative stimulation (PAS) to induce neuroplasticity. Motor performance was assessed using the Purdue Pegboard. ResultsPatients showed improvements in bilateral motor performance from [~]3 to [~]6 weeks post-injury. PAS did not induce any change in net motor cortex excitability or SICI but increased LICI, which was greatest [~]6 weeks post-injury. Adjusted modelling showed that greater PAS-induced increase in LICI was associated with better bilateral motor performance, suggesting an association between PAS-induced neuroplasticity of GABAB-mediated inhibition and motor function following burn injury. ConclusionsThese findings highlight a potential role for neuroplasticity of inhibitory circuits in the motor cortex in recovery of motor function following burn injury. The data provide a neurophysiological basis to test whether targeting inhibitory networks in the subacute period after burn injury can enhance or expedite functional recovery.

BackgroundRestless legs syndrome (RLS) is a common neurological disorder whose pathophysiology remains poorly understood. Previous neuroelectrophysiological studies have found a widespread increase in neural excitability. Potassium channels are fundamental determinants of neuronal excitability through their control of resting membrane potential and firing threshold. Mendelian randomization (MR) analysis provides a powerful method for studying the potential relationship between the regulatory function of potassium channels and RLS. MethodsIn the exploration phase, based on MR analysis and enrichment analysis results of opioids use, cerebrospinal fluid (CSF) and brain metabolites, and different RLS datasets, it is proposed that potassium channels may play a potential role in RLS. Subsequently, cis-MR across different RLS datasets based on KCN-genes OpenGWAS eQTLs and brain single cell eQTLs (sc-eQTLs) were used for further discovery. Using data from external experiments, differential expression analysis of KCN-genes was performed in human neural stem cells with MEIS1 gene knockout and overexpression. In addition, through assuming the regulation of potassium channels in the opioids treatment and the role of mediating factors, an exploratory simulation model was designed to simulate the dynamic relationship and explore the potential influencing factors between opioids and RLS. ResultsThis study conducted exploratory MR analysis between the genome-wide association study (GWAS) data for opioids use and RLS, and four candidate mediators were found and evaluated in mediation analysis using 1402 CSF and brain metabolites as mediators. Enrichment analyses across different RLS datasets of genes mapped from instrumental variable linked to RLS-related candidate metabolites showed, the mechanism of RLS may be related to potassium channels, membrane potential regulation, synaptic function and addiction. Based on these clues, further exploration was conducted on the causal relationship between potassium channels and RLS. eQTLs of KCN-designated genes (KCN-genes) were obtained from the OpenGWAS website and subjected to single gene cis-MR analysis, and the results showed that 13 KCN-genes were significantly correlations with RLS. The further analysis based on sc-eQTLs supports higher expression of KCNAB1 gene in oligodendrocytes and KCNMA1 gene in microglia were associated with higher RLS risk. Differential expression analysis of KCN-genes between MEIS1 gene knockout and overexpression showed the regulatory mode of MEIS1 on different KCN-genes. ConclusionThis study provides the genetic support and preliminary multi method evaluation for understanding the relationship between potassium channel regulation and RLS, and proposes "Membrane Potential Disturbance" hypothesis, that may suggest a new perspective and framework for understanding the pathophysiology of RLS.

IntroductionEarly language development in infants is being increasingly studied, though only recently with direct measurements of brain activity rather than with behavioral or physiological measurements. In the current study, we use electroencephalographic (EEG) recordings of 2-week-old infants to look for signs of prenatal learning and to investigate newborns abilities to process language. We also look at the influence of prenatal stress factors and at the predictive value of the newborns language processing abilities for later language development. MethodsSixty pregnant women played a rhyme to their abdomen twice a day from the 34th week of pregnancy until birth, to familiarize the fetus with the rhyme. At around 2 weeks after delivery (mean age 16 days), the newborns were exposed to the familiar rhyme as well as to an unfamiliar one while their EEG was recorded. Additionally, three manipulations of the familiar rhyme were played: (1) low-pass filtered, (2) with changed rhythm, and (3) inverted and played backwards. The data was analyzed to see how well the infant brain signal followed the speech envelope in each condition. Accounting for the heterogenous approach used for neural speech tracking in the literature, we used four methods, namely: (1) coherence, (2) Hilbert coherence, (3) temporal response functions (TRF), and (4) mutual information (MI). The maternal prenatal depression was evaluated with Edinburgh Prenatal Depression Score and the chronic fetal stress was measured from the hair cortisol levels of the 2 week-olds. The language development at 6 months of age was evaluated with the Bayley Scales. Results and discussionOverall, the results indicate the presence of prenatal learning, with the unfamiliar rhyme eliciting stronger cortical tracking (higher coherence and MI) than the familiar rhyme, which suggests stronger brain-to-speech coupling for the unfamiliar rhyme, perhaps deriving from more effort to process the unexpected stimulus. However, the original version of the familiar rhyme proved to be the easiest to track compared to the language- and rhythm-manipulations, (higher MI for the original rhyme than the language manipulation and higher coherence and mTRF correlation coefficients for the original rhyme than the rhythm manipulation). This indicates language discrimination and a prosodic-based learning of the familiar rhyme. Furthermore, there is an indication of phonotactic sensitivity at this young age, with less tracking (lower Hilbert coherence and lower mTRF correlation coefficients) of the low-pass filtered rhyme than the original version, indicating that the phonological cues erased by the filtering were important for the newborns ability to follow the rhyme. Furthermore, the mothers depression scores positively correlated with the infants tracking ability for the familiar rhyme. This suggests that a slightly lower mood was more stimulative for the fetal language development. The chronic fetal stress levels, however, were negatively correlated with the cortical tracking abilities. Importantly, the newborns cortical tracking was positively correlated with the infants language development at 6 months of age, underlining the predictive value of the early assessment of language processing. ConclusionPrenatal learning is well established, but evidence including (healthy) brain data in the first weeks of life is scarce. The current study shows that newborns can discriminate between a familiar and unfamiliar rhyme, while also highlighting the role of prosody in early language processing, and bringing new evidence of their sensitivity to phonotactic cues in auditory stimuli. Furthermore, the newborns ability to track a rhyme is correlated with their language development at 6 months. The newborns cortical tracking of the familiar rhyme is further increased by moderately low maternal mood, but decreased by fetal stress. Future studies with similar fine-grained linguistic designs but of older infants should teach us the timeline of what exactly is learned prenatally and at very early age in respect to language.

Fibromyalgia is characterized by widespread musculoskeletal pain accompanied by sleep disturbances and cognitive dysfunction, among other symptoms. Patients frequently report difficulties with memory, but objective assessment of these impairments remains limited. This study aimed to evaluate working memory performance in fibromyalgia patients using two established paradigms: the change detection task, which primarily measures storage capacity, and the n-back task, which assesses both storage and manipulation of information. For the change detection task, the behavioral outcomes assessed were the hit rate, false alarm rate, capacity estimate and response times. The electrophysiological measure evaluated was the contralateral delayed activity. For the n-back, the behavioral outcomes were the same, except for the capacity estimate. Electrophysiologically, the P2 and P3 from the evoked potentials were the outcomes of the task. Behaviorally, results demonstrated that fibromyalgia patients exhibited lower memory capacity than controls (1.90 vs 2.64), in the change detection task, which involved differences in the hit rate and false alarm rate, whereas no behavioral differences were found for the n-back task. In contrast, no differences were found for any of the electrophysiological outcomes in any of the tasks. Taken together, we found evidence supporting a reduction in working memory capacity in fibromyalgia, although it is not reflected in electrophysiological measures.

BackgroundNerve conductive studies (NCS) are the most informative portion of the electrodiagnostic evaluation for peripheral neuropathy; NCS can be extremely useful both in localizing lesions and determining the pathological processes. Recently, there is increased interest in quality of normative values for each test result and compare should be done between normal and patients regarding specific disease. So, The aim of our study is to help establish NCS normative data of tibial nerve that could be applicable in the Sudanese population and can be used in neurophysiology departments around the country and to compare with those data published in the literature, and to survey the effects of Age, Gender, Height, Weight and Temperature on Nerve Conduction Study Parameters. MethodsNCSs were performed in 210 tibial nerves of 105 adult healthy Sudanese subjects using standardized techniques. ResultsIt was found that the tibial nerve component values as follows; the distal latency is 4.063{+/-}1.0533 m/sec, Proximal latency 13.238 {+/-}1.7253 m/sec, Conduction velocity 48.58{+/-}5.634 m/sec, F wave 51.509{+/-}6.1013 m/sec, Duration of CMAP at ankle 6.199{+/-} 1.0254 m/sec, Amplitude of CMAP at ankle 8.528{+/-}3.6658 V, Area of CMAP at ankle 17.569{+/-}7.7389V/ms, Duration of CMAP at popliteal 7.075{+/-}1.3173 m/sec, Amplitude of CMAP at popliteal 6.343{+/-}3.2871V and Area at popliteal 14.914{+/-}7.8684 V/ms. ConclusionThe tibial motor nerve conduction parameters for the tested nerve compared favorably with the existing literature with some discrepancies that were justified SignificanceThis is the first study to establish reference values for tibial NCS carried out Sudanese population.

The neuromodulatory effects of repetitive transcranial magnetic stimulation (rTMS) are often described as inhibiting for low frequency and facilitating for high frequency protocols, leading to the lofi-hife heuristic. However, the data basis for this is inconsistent and reliability of rTMS is barely evaluated. The present study examines the validity of this lofi-hife heuristic at group and single subject level and the reliability of rTMS in a non-navigated setting close to clinical application. In 30 healthy participants, 1 Hz and 20 Hz rTMS were each administered twice over the left motor cortex resulting in four sessions/participant. Motor evoked potentials (MEPs) were measured before and after each session. Reliability measures were intraclass and Pearsons correlation coefficient (ICC and r). The heuristic was not evident at group level. At single-subject level four participants responded with heuristic-conform changes, i.e., concomitant decreases for 1 Hz and increases for 20 Hz sessions. ICCs and r were low to moderate. Within subgroups of less confounded measures, we found good r values for 20 Hz rTMS. Results demonstrate high inter- and intraindividual variability of rTMS questioning the lofi-hife heuristic. Methodological improvements for the usage of rTMS might help to increase validity and reliability of non-invasive brain stimulation.

Recently we proposed and tested a novel framework based on information theory about the features of agrammatism in patients with the nonfluent variant of primary progressive aphasia (nfvPPA). These features include short sentences, simplified structures, the omission of function words, reduced use of verbs, and increased use of heavy verbs. After distinguishing the syntactic and lexical features of agrammatism, we proposed that the lexical features are not defects but rather a compensatory response to structural deficits. We showed that although patients with nfvPPA have difficulty using complex structures, they use more informative words to facilitate the transfer of their intended message. In this work, we demonstrated the generalizability of our findings to patients with Brocas aphasia who share similar neuroanatomical involvements with patients with nfvPPA. We found that patients with Brocas aphasia use simpler syntactic structures as measured by higher syntax frequency. We also found that the use of simpler syntax predicts the use of lower-frequency words. Furthermore, our study showed that producing sentences of lower word frequency is likely achieved through the canonical features of agrammatism, i.e., higher proportions of content words over function words, nouns over verbs, and heavy verbs over light verbs.