Thalamo-Sensorimotor Functional Connectivity Correlates with World Ranking of Olympic, Elite, and High Performance Athletes

Contralateral thalamocortical connectivity is related to postural control in the uninvolved limb of older adults with history of ankle sprain

BACKGROUND

Sensorimotor brain connectivity is often overlooked when determining relationships between postural control and motor performance following musculoskeletal injury. Thalamocortical brain connectivity is of particular interest as it represents the temporal synchrony of functionally and anatomically linked brain regions. Importantly, adults over the age of 60 are especially vulnerable to musculoskeletal injury due to age-related declines in postural control and brain connectivity.

RESEARCH QUESTION

Is there a relationship between thalamocortical connectivity and static postural control in older adults with a history of LAS?

METHODS

Data were analyzed from twenty older adults (mean age = 67.0 ± 4.3 yrs; 13 females) with a history of LAS. The sensorimotor network (SMN) was identified from resting-state MRI data, and a priori thalamic and postcentral gyri regions of interest were selected in order to determine left and right hemisphere thalamocortical connectivity. Balance was assessed for the involved and non-involved limbs via center of pressure velocity (COPV) in the medial-lateral (ML) and anterior-posterior (AP) directions.

RESULTS

Contralateral thalamocortical connectivity was significantly associated with COPV_ML COPV_ML (r = -0.474, P = 0.05) and COPV_AP (r = -0.622, P = 0.008) in the non-involved limb. No significant association was observed between involved limb balance and contralateral thalamocortical connectivity (COPV_ML: r = -0.08, P = 0.77; COPV_AP: r = 0.12, P = 0.63).

SIGNIFICANCE

A significant relationship between thalamocortical connectivity and static postural control was observed in the non-involved, but not the involved limb in older adults with a history of LAS. Findings suggest that thalamocortical connectivity may lead to or be the product of LAS.

Effect of different sport environments on proactive and reactive motor inhibition: A study on open- and closed-skilled athletes via mouse-tracking procedure

This study aimed to investigate the effect of different sport environments (open-and closed-skill sports) on proactive and reactive inhibitory processes as two distinct components of motor inhibition. A mouse-tracking procedure was employed to compare behavioral performance among three groups of participants (tennis players, swimmers and non-athletes) in non-sport-specific cued Go/No-Go (GNG) and Stop Signal Task (SST), which mainly engage proactive and reactive inhibitory control, respectively. Reaction times (RTs), inhibitory failures, and Stop Signal Reaction Times (SSRTs) were measured. To investigate dynamic aspects of inhibitory control, movement trajectories classified as one-shot (absence of trajectory alteration reflected in a steep slope) or non-one-shot (non-linear/multipeaked trajectory, with one or multiple corrections) were analyzed and compared among groups. Results showed no group differences in RTs in Go/No-Go and Stop conditions. SSRTs were significant shorter for the athletes than non-athletes in SST, but no differences emerged for inhibitory failures in cued GNG. During inhibitory failures athletes showed higher proportion of non-one-shot movements than non-athletes. Higher proportion of non-one-shot profiles was observed in cued GNG compared to SST. Finally, no differences between open-and closed-skilled athletes were found in both tasks. Our findings suggest that both proactive and reactive inhibitory controls do benefit from sport practice, but open-and closed-skill sports do not differ in influencing inhibitory processes. Movement profile analysis could be a promising, complementary behavioral analysis to integrate for more fine-grained evaluation and differentiation of inhibitory motor control in athletes, specifically when using GNG tasks.

Walking, Running, Swimming: An Analysis of the Effects of Land and Water Aerobic Exercises on Cognitive Functions and Neural Substrates

In the brain and cognitive reserves framework, aerobic exercise is considered as a protective lifestyle factor able to induce positive effects on both brain structure and function. However, specific aspects of such a beneficial effect still need to be completely clarified. To this aim, the present narrative review focused on the potential brain/cognitive/neural reserve-construction mechanisms triggered by different aerobic exercise types (land activities; such as walking or running; vs. water activities; such as swimming), by considering human and animal studies on healthy subjects over the entire lifespan. The literature search was conducted in PubMed database. The studies analyzed here indicated that all the considered kinds of activities exert a beneficial effect on cognitive/behavioral functions and on the underlying brain neurobiological processes. In particular, the main effects observed involve the cognitive domains of memory and executive functions. These effects appear related to structural and functional changes mainly involving the fronto-hippocampal axis. The present review supports the requirement of further studies that investigate more specifically and systematically the effects of each type of aerobic activity, as a basis to plan more effective and personalized interventions on individuals as well as prevention and healthy promotion policies for the general population.

Exercise Intensity and Brain Plasticity: What’s the Difference of Brain Structural and Functional Plasticity Characteristics Between Elite Aerobic and Anaerobic Athletes?

This study investigated the differences in morphometry and functional plasticity characteristics of the brain after long-term training of different intensities. Results showed that an aerobic group demonstrated higher gray matter volume in the cerebellum and temporal lobe, while an anaerobic group demonstrated higher gray matter volume in the region of basal ganglia. In addition, the aerobic group also showed significantly higher fractional amplitude of low-frequency fluctuation (fALFF) and degree centrality (DC) in the motor area of the frontal lobe and parietal lobe, and the frontal gyrus, respectively. At the same time, the anaerobic group demonstrated higher fALFF and DC in the cerebellum posterior lobe (family-wise error corrected, p < 0.01). These findings may further prove that different brain activation modes respond to different intensities of physical activity and may help to reveal the neural mechanisms that can classify athletes from different intensity sports.

Different unilateral force control strategies between athletes and non-athletes

This study investigated continuous visuomotor tracking capabilities between athletes and non-athlete controls using isometric force control paradigm. Nine female athletes and nine female age-matched controls performed unilateral hand-grip force control tasks with their dominant and non-dominant hands at 10% and 40% of maximal voluntary contraction (MVC), respectively. Three conventional outcome measures on force control capabilities included mean force, force accuracy, and force variability, and we additionally calculated two nonlinear dynamics variables including force regularity using sample entropy and force stability using maximal Lyapunov exponent. Finally, we performed correlation analyses to determine the relationship between nonlinear dynamics variables and conventional measures for each group. The findings indicated that force control capabilities as indicated by three conventional measures were not significantly different between athlete and non-athlete control groups. However, the athletes revealed less force regularity and greater force stability across hand conditions and targeted force levels than those in non-athlete controls. The correlation analyses found that increased force regularity (i.e., less sample entropy values) at 10% of MVC and decreased force regularity (i.e., greater sample entropy values) at 40% of MVC were significantly related to improved force accuracy and variability for the athlete group, and these patterns were not observed in the non-athlete control group. These findings suggested that the athletes may use different adaptive force control strategies as indicated by nonlinear dynamics tools.

Potential Genetic Contributions of the Central Nervous System to a Predisposition to Elite Athletic Traits: State-of-the-Art and Future Perspectives

Recent remarkable advances in genetic technologies have allowed for the identification of genetic factors potentially related to a predisposition to elite athletic performance. Most of these genetic variants seem to be implicated in musculoskeletal and cardiopulmonary functions. Conversely, it remains unclear whether functions of the central nervous system (CNS) genetically contribute to elite athletic traits, although the CNS plays critical roles in exercise performance. Accumulating evidence has highlighted the emerging implications of CNS-related genes in the modulation of brain activities, including mental performance and motor-related traits, thereby potentially contributing to high levels of exercise performance. In this review, recent advances are summarized, and future research directions are discussed in regard to CNS-related genes with potential roles in a predisposition to elite athletic traits.

Cognitive training in elite soccer players: evidence of narrow, but not broad transfer to visual and executive function

Visual and executive functions have been suggested to be crucial in high-demanding team sports. Consequently, the interest in evaluating training possibilities of these functions is relatively high. However, easily applicable training tools, as well as evidence of their efficacy, especially in the present group of age (i.e. 17–21 years) and performance level, are scarce. Therefore, the present study aimed to evaluate the effectiveness and transfer of an essential cognitive training tool (i.e. NeuroTracker [NT] three dimensional [3D] multiple-object tracking [MOT]) in youth elite soccer players. Visual and executive functions were analyzed in a pre–post test design with an intervention and a control group after 10 weeks of training twice a week. Physical activity was included as a possible covariate. Results show meaningful benefits in the trained ability (i.e. MOT) besides small but negligible improvements in visual clarity and inhibition for the intervention group. Consequently, strict single-task NT 3D-MOT seems to have little transfer to other visual or executive functions. However, future studies should investigate the effects of sport-specific dual-task NT 3D-MOT to analyze possible multitasking adaptations further.

Occupational Neuroplasticity in the Human Brain: A Critical Review and Meta-Analysis of Neuroimaging Studies

Many studies have revealed the structural or functional brain changes induced by occupational factors. However, it remains largely unknown how occupation-related connectivity shapes the brain. In this paper, we denote occupational neuroplasticity as the neuroplasticity that takes place to satisfy the occupational requirements by extensively professional training and to accommodate the long-term, professional work of daily life, and a critical review of occupational neuroplasticity related to the changes in brain structure and functional networks has been primarily presented. Furthermore, meta-analysis revealed a neurophysiological mechanism of occupational neuroplasticity caused by professional experience. This meta-analysis of functional neuroimaging studies showed that experts displayed stronger activation in the left precentral gyrus [Brodmann area (BA)6], left middle frontal gyrus (BA6), and right inferior frontal gyrus (BA9) than novices, while meta-analysis of structural studies suggested that experts had a greater gray matter volume in the bilateral superior temporal gyrus (BA22) and right putamen than novices. Together, these findings not only expand the current understanding of the common neurophysiological basis of occupational neuroplasticity across different occupations and highlight some possible targets for neural modulation of occupational neuroplasticity but also provide a new perspective for occupational science research.

Intrinsic brain activity of subcortical-cortical sensorimotor system and psychomotor alterations in schizophrenia and bipolar disorder: A preliminary study

OBJECTIVE

Alterations in psychomotor dimension cut across different psychiatric disorders, such as schizophrenia (SCZ) and bipolar disorder (BD). This preliminary study aimed to investigate the organization of intrinsic brain activity in the subcortical-cortical sensorimotor system in SCZ (and BD) as characterized according to psychomotor dimension.

METHOD

In this resting-state functional magnetic resonance imaging (fMRI) study, functional connectivity (FC) between thalamus and sensorimotor network (SMN), along with FC from substantia nigra (SN) and raphe nuclei (RN) to basal ganglia (BG) and thalamic regions, were investigated by using an a-priori-driven and dimensional approach. This was done in two datasets: SCZ patients showing inhibited psychomotricity (n = 18) vs. controls (n = 19); SCZ patients showing excited psychomotricity (n = 20) vs. controls (n = 108). Data from a third dataset of BD in inhibited depressive or manic phases (reflecting inhibited or excited psychomotricity) were used as control.

RESULTS

SCZ patients suffering from psychomotor inhibition showed decreased thalamus-SMN FC toward around-zero values paralleled by a concomitant reduction of SN-BG/thalamus FC and RN-BG/thalamus FC (as BD patients in inhibited depression). By contrast, SCZ patients suffering from psychomotor excitation exhibited increased thalamus-SMN FC toward positive values paralleled by a concomitant reduction of RN-BG/thalamus FC (as BD patients in mania).

CONCLUSIONS

These findings suggest that patients exhibiting low or high levels of psychomotor activity show distinct patterns of thalamus-SMN coupling, which could be traced to specific deficit in SN- or RN-related connectivity. Notably, this was independent from the diagnosis of SCZ or BD, supporting an RDoC-like dimensional approach to psychomotricity.

Abnormal Functional Relationship of Sensorimotor Network With Neurotransmitter-Related Nuclei via Subcortical-Cortical Loops in Manic and Depressive Phases of Bipolar Disorder

OBJECTIVE

Manic and depressive phases of bipolar disorder (BD) show opposite psychomotor symptoms. Neuronally, these may depend on altered relationships between sensorimotor network (SMN) and subcortical structures. The study aimed to investigate the functional relationships of SMN with substantia nigra (SN) and raphe nuclei (RN) via subcortical-cortical loops, and their alteration in bipolar mania and depression, as characterized by psychomotor excitation and inhibition.

METHOD

In this resting-state functional magnetic resonance imaging (fMRI) study on healthy (n = 67) and BD patients (n = 100), (1) functional connectivity (FC) between thalamus and SMN was calculated and correlated with FC from SN or RN to basal ganglia (BG)/thalamus in healthy; (2) using an a-priori-driven approach, thalamus-SMN FC, SN-BG/thalamus FC, and RN-BG/thalamus FC were compared between healthy and BD, focusing on manic (n = 34) and inhibited depressed (n = 21) patients.

RESULTS

(1) In healthy, the thalamus-SMN FC showed a quadratic correlation with SN-BG/thalamus FC and a linear negative correlation with RN-BG/thalamus FC. Accordingly, the SN-related FC appears to enable the thalamus-SMN coupling, while the RN-related FC affects it favoring anti-correlation. (2) In BD, mania showed an increase in thalamus-SMN FC toward positive values (ie, thalamus-SMN abnormal coupling) paralleled by reduction of RN-BG/thalamus FC. By contrast, inhibited depression showed a decrease in thalamus-SMN FC toward around-zero values (ie, thalamus-SMN disconnection) paralleled by reduction of SN-BG/thalamus FC (and RN-BG/thalamus FC). The results were replicated in independent HC and BD datasets.

CONCLUSIONS

These findings suggest an abnormal relationship of SMN with neurotransmitters-related areas via subcortical-cortical loops in mania and inhibited depression, finally resulting in psychomotor alterations.

Altered Central Autonomic Network in Baseball Players: A Resting-state fMRI Study

The physiological adaptive regulation of healthy population with a high fitness level is associated with enhanced cognitive control in brain. This study further investigated the effects of different levels of sporting experience on intrinsic brain networks involved in central autonomic processing using resting-state functional magnetic resonance imaging. We explored functional connectivity of four core regions within central autonomic network (CAN), namely posterior midcingulate cortex (pMCC), left amygdala (AMYG), and right anterior (aINS) and left posterior insular cortices, in advanced and intermediate baseball players, and compared their strength of connectivity with individuals without baseball-playing experience. Functional connectivity maps across three groups confirmed a close relationship between CAN and large-scale brain networks in sensory, motor and cognitive domains. Crucially, both advanced and intermediate batters demonstrated enhanced connectivity between pMCC and sensorimotor network, between right aINS and dorsal anterior cingulate cortex, and between left AMYG and right putamen, than controls. These results reflected a stronger interregional coupling in sensorimotor and cognitive control, and in motor skill consolidation. In conclusion, we provided evidence that different levels of sporting experience could reorganize/enhance intrinsic functional connectivity for central autonomic processing.