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Motor control, a ubiquitous part of driving, requires increased cognitive controlled processing in older adults relative to younger adults. However, the influence of aging on motor-related neural mechanisms in the context of driving has rarely been studied. The present study aimed to identify age-related changes in cognitive control and attention allocation during a simulated steering task, using electroencephalography. Midfrontal theta, a marker for cognitive control, and posterior alpha power, a marker for attention allocation, were measured in a total of 26 young, 25 middle-aged, and 28 older adults. By adapting driving speed, the difficulty level of this steering task was individualized for each participant. Results show age-related changes in midfrontal theta power, but not in posterior alpha power, despite similar steering accuracy across age groups. Specifically, only younger and, to a lesser extent, middle-aged adults exhibited increased theta power while driving through more demanding curved segments relative to straight segments. In contrast, theta power upregulation was absent in older adults, suggesting a saturation of cognitive resources while driving, possibly due to a limitation in resource capacity, or less automatic motor-related neural processing.

Interlimb coordination deteriorates as a result of aging. Due to its ubiquity in daily life, a greater understanding of the underlying neurophysiological changes is required. Here, we combined electroencephalography time-frequency spectral power and functional connectivity analyses to provide a comprehensive overview of the neural dynamics underlying the age-related deterioration of interlimb coordination involving all four limbs. Theta, alpha and beta oscillations in the frontal, central and parietal regions were analyzed in twenty younger (18-30 years) and nineteen older adults (65-78 years) during a complex interlimb reaction time task. Reaction time was significantly higher in older adults across all conditions, and the discrepancy between both age groups was largest in the most complex movement condition. Older adults demonstrated enhanced beta event-related desynchronization (i.e., the attenuation of beta power), which further increased along with task complexity and was positively linked to behavioral performance. Theta functional connectivity between frontal, central and parietal regions generally increased with movement complexity, irrespective of age group. In general, frontoparietal alpha band functional connectivity tended to be reduced in older versus younger adults, although these contrasts did not survive multiple comparison corrections. Overall, spectral results suggest that enhanced beta desynchronization in older adults reflects a successful compensatory mechanism to cope with increased difficulty during complex interlimb coordination. Functional connectivity results suggest that theta and alpha band connectivity are prone to respectively task- and age-related modulations. Future work could target these spectral and functional connectivity dynamics through noninvasive brain stimulation to potentially improve interlimb coordination in older adults.

Bimanual coordination is an important part of everyday life and recruits a large neural network, including the cerebellum. The specific role of the cerebellum in bimanual coordination has not yet been studied in depth, although several studies indicate a differential role of the anterior and posterior cerebellum depending on the complexity of the coordination. An activation likelihood estimation (ALE) meta-analysis was used combining the data of several functional MRI studies involving bimanual coordination tasks with varying complexities to unravel the involvement of the different areas of the cerebellum in simple and complex bimanual coordination. This study confirms the general bimanual network as found by Puttemans et al. (Puttemans et al. in J Neurosci 25:4270-4278, 2005) and highlights the differences between preferred in-phase (simultaneous movements of homologous muscle groups) and anti-phase movement conditions (alternating movements of homologous muscle groups), and more complex, non-preferred bimanual movements (e.g., out-of-phase movements). Our results show a differential role for the anterior and posterior vermis in bimanual coordination, with a role for the anterior vermis in anti-phase and complex bimanual coordination, and an exclusive role for the posterior vermis in complex bimanual movements. In addition, the way complexity was manipulated also seems to play a role in the involvement of the anterior and posterior vermis. We hypothesize that the anterior vermis is involved in sequential/spatial control, while the posterior vermis is involved in temporal control of (bimanual) coordination, though other factors such as (visual) feedback and continuity of the movement also seem to have an impact. More studies are needed to unravel the specific role of the cerebellar vermis in bimanual coordination.

Objective To systematically review how patient characteristics and/or transcranial direct current stimulation (tDCS) parameters influence tDCS effectiveness in respect to upper limb function post-stroke. Methods Three electronic databases were searched for sham-controlled randomised trials using the Fugl-Meyer Assessment for upper extremity as outcome measure. A meta-analysis and nine subgroup-analyses were performed to identify which tDCS parameters yielded the greatest impact on upper limb function recovery in stroke patients. Results Eighteen high-quality studies (507 patients) were included. tDCS applied in a chronic stage yields greater results than tDCS applied in a (sub)acute stage. Additionally, patients with low baseline upper limb impairments seem to benefit more from tDCS than those with high baseline impairments. Regarding tDCS configuration, all stimulation types led to a significant improvement, but only tDCS applied during therapy, and not before therapy, yielded significant results. A positive dose–response relationship was identified for current/charge density and stimulation duration, but not for number of sessions. Conclusion Our results demonstrate that tDCS improves upper limb function post-stroke. However, its effectiveness depends on numerous factors. Especially chronic stroke patients improved, which is promising as they are typically least amenable to recovery. Significance The current work highlights the importance of several patient-related and protocol-related factors regarding tDCS effectiveness.

Older drivers are at a severely higher risk for motor vehicle crash involvement. Due to the global aging of the population, this increased crash risk has a significant impact on society, as well as on an older individual’s quality of life. For this reason, there is a need for understanding how normal age-related changes in cognition and underlying brain dynamics impact driving performance to identify the functional and neurophysiological biomarkers that could be used to design strategies to preserve or improve safe driving behavior in older persons. This review provides an overview of the literature on age-related changes in cognitive functioning and brain dynamics that impact driving simulator performance of healthy persons. A systematic literature search spanning the last ten years was conducted, resulting in 22 eligible studies. Results indicated that various aspects of cognition, most importantly executive function, complex attention, and dual tasking, were associated with driving performance, irrespective of age. However, there was a distinct age-related decline in cognitive and driving performance. Older persons had a more variable, less consistent driving simulator performance, such as more variable speed adaptation or less consistent lane keeping behavior. Only a limited number of studies evaluated the underlying brain dynamics in driving performance. Therefore, future studies should focus on implementing neuroimaging techniques to further unravel the neural correlates of driving performance.

uptake after tDCS in the bilateral precentral gyri, the bilateral postcentral gyri, the left cingulate, and the left SMA (p(FWE) < 0.028). These results suggest that perceptions of fatigue and QoL, but not objective performance fatigability, play a prominent role in Post-COVID-19-Fatigue and that tDCS might alter cerebral FDG uptake in fatigue-related brain regions in these patients. Abstract A randomized interventional cross-over trial with transcutaneous auric-ular vagus nerve stimulation (tVNS) was performed on 13 adult Systemic sclerosis (SSc) patients with chronic moderate-to-severe pain from the Scleroderma Unit of Policlinico Hospital in Milan. Patients were randomly assigned to the interventional group with tVNS (25 Hz) or to the control group based on sham stimulation (1 Hz) for 4 not consecutively hours/day for one month. Each group shifted to the opposite arm after a 4-weeks wash-out period. Pain was assessed by Numeric Rating Scale (NRS) and 10-minute ECG was recorded at rest before and after real tVNS and sham. Symbolic Heart Rate Variability (HRV) analysis was performed on ECG to assess the cardiovascular autonomic control. ANCOVA test correcting for baseline values, age, disease duration and month of treatment was used to evaluate NRS or HRV changes after tVNS and sham stimulation. For HRV statistical analysis, cardiac ejection fraction and systolic pulmonary artery pressure were also included as covariates. A linear regression model, correcting for covariates as described above, was performed to evaluate the occurrence of minimal clinically important difference (at least 2 points on NRS). Partial correlation analysis was used to estimate the relationship between NRS and HRV changes after correction for covariates. Statistical analysis showed a significant improvement of NRS score after tVNS with an estimated reduction of 2.051 NRS points (p

The role of the dorsolateral prefrontal cortex (DLPFC) in the regulation of bimanual coordination appears to become crucial with aging. Age-related changes in the involvement of the DLPFC in bimanual coordination were studied by using disruptive repetitive TMS (rTMS), inducing a transient lesion in this brain structure. Neurophysiological as well as behavioral effects of suppressing DLPFC during the preparation and execution of a bimanual task were studied in 41 healthy adults (young and old). Specifically, we combined short-train rTMS with single pulse TMS to examine the effect of DLPFC suppression on the interhemispheric projection to the contralateral primary motor cortex (M1) during motor preparation. Findings revealed that compromised interhemispheric DLPFC-M1 disinhibition during motor preparation in older adults resulted in less accurate bimanual performance. The altered DLPFC-M1 interaction in older adults appeared to result from a decline in local inhibitory mechanisms in the DLPFC. In addition, the induction of DLPFC suppression affected task accuracy, but not movement stability in both age groups. Taken together, these results suggest that DLPFC acts as a key regulator in the control of bimanual movement coordination.