There are a limited number of neuroimaging investigations into motor control of the lumbopelvic musculature. Most investigation examining motor control of the lumbopelvic musculature utilize transcranial magnetic stimulation and focus primarily on the motor cortex. This has resulted in a dearth of knowledge as it relates to how other regions of the brain activate during lumbopelvic movement. Additionally, task-based functional connectivity during lumbopelvic movements has not been well elucidated. Therefore, we used functional magnetic resonance imaging to (...) examine brain activation and ROI-to-ROI task-based functional connectivity in 19 healthy individuals during the performance of three lumbopelvic movements: modified bilateral bridge, left unilateral bridge, and right unilateral bridge. The whole brain analysis found robust, bilateral activation within the motor regions of the brain during the bilateral bridge task, and contralateral activation of the motor regions during unilateral bridging tasks. Furthermore, the ROI-to-ROI analysis demonstrated significant connectivity of a motor network that included the supplemental motor area, bilateral precentral gyrus, and bilateral cerebellum regardless of the motor task performed. These data suggest that while whole brain activation reveals unique patterns of activation across the three tasks, functional connectivity is very similar. As motor control of the lumbopelvic area is of high interest to those studying low back pain, this study can provide a comparison for future research into potential connectivity changes that occur in individuals with LBP. (shrink)

Repeatedly performing a submaximal motor task for a prolonged period of time leads to muscle fatigue comprising a central and peripheral component, which demands a gradually increasing effort. However, the brain contribution to the enhancement of effort to cope with progressing fatigue lacks a complete understanding. The intermittent motor tasks closely resemble many activities of daily living, thus remaining physiologically relevant to study fatigue. The scope of this study is therefore to investigate the EEG-based brain activation patterns (...) in healthy subjects performing IMT until self-perceived exhaustion. Fourteen participants repeated elbow flexion contractions at 40% maximum voluntary contraction by following visual cues displayed on an oscilloscope screen until subjective exhaustion. Each contraction lasted ≈5 s with a 2-s rest between trials. The force, EEG, and surface EMG data were simultaneously collected. After preprocessing, we selected a subset of trials at the beginning, middle, and end of the study session representing brain activities germane to mild, moderate, and severe fatigue conditions, respectively, to compare and contrast the changes in the EEG time-frequency characteristics across the conditions. The outcome of channel- and source-level TF analyses reveals that the theta, alpha, and beta power spectral densities vary in proportion to fatigue levels in cortical motor areas. We observed a statistically significant change in the band-specific spectral power in relation to the graded fatigue from both the steady- and post-contraction EEG data. The findings would enhance our understanding on the etiology and physiology of voluntary motor-action-related fatigue and provide pointers to counteract the perception of muscle weakness and lack of motor endurance associated with ADL. The study outcome would help rationalize why certain patients experience exacerbated fatigue while carrying out mundane tasks, evaluate how clinical conditions such as neurological disorders and cancer treatment alter neural mechanisms underlying fatigue in future studies, and develop therapeutic strategies for restoring the patients' ability to participate in ADL by mitigating the central and muscle fatigue. (shrink)

PurposeThis study aimed to investigate whether oxygenated hemoglobin generated during a motor imagery task is associated with the motor learning level of the task.MethodsWe included 16 right-handed healthy participants who were trained to perform a ball rotation task. Hemodynamic brain activity was measured using near-infrared spectroscopy to monitor changes in oxy-Hb concentration during the BR MI task. The experimental protocol used a block design, and measurements were performed three times before and after the initial (...) training of the BR task as well as after the final training. The BR count during training was also measured. Furthermore, subjective vividness of MI was evaluated three times after NIRS measurement using the Visual Analog Scale.ResultsThe results showed that the number of BRs increased significantly with training. VAS scores also improved with training. Furthermore, oxy-Hb concentration and the region of interest showed a main effect. An interaction was confirmed, and it was ascertained that the change in oxy-Hb concentrations due to training was different for each ROI. The most significant predictor of subjective MI vividness was supplementary motor area oxy-Hb concentration.DiscussionHemodynamic brain activity during MI tasks may be correlated with task motor learning levels, since significant changes in oxy-Hb concentrations were observed following initial and final training in the SMA. In particular, hemodynamic brain activity in the SMA was suggested to reflect the MI vividness of participants. (shrink)

Previous studies have shown that the color red can affect basic motor functioning. However, these studies utilized simple gross motor tasks rather than those assessing complex fine motor skills. Moreover, these empirical studies were theoretically based on the threat–behavior link in human and non-human animals, and neglected the relationship between arousal and motor performance. According to the Yerkes–Dodson law and the inverted-U hypothesis in sport psychology, for simple motor tasks, high arousal is more advantageous than (...) low arousal ; for complex motor tasks, low arousal is more advantageous than high arousal. The current research examined the effect of color on different kinds of motor skills based on the inverted U-hypothesis. In Experiment 1, we examined the effect of red and blue on dart-throwing performance, whereas in Experiment 2, we examined the effect of red and blue on grip strength performance. The results showed that performance of fine motor skill in the blue condition was better than in the red condition, and performance of gross motor skill in the red context was better than in the blue context. These results indicate that the type of motor skill assessed moderates the influence of red and blue on motor performance. (shrink)

Visual information follows at least two branches in the human nervous system, following a common input stage: a cognitive ''what'' branch governs perception and experience, while a sensorimotor ''how'' branch handles visually guided behavior though its outputs are unconscious. The sensorimotor system is probed with an isomorphic task, requiring a 1:1 relationship between target position and motor response. The cognitive system, in contrast, is probed with a forced qualitative decision, expressed verbally, about the location of a target. Normally, (...) the cognitive system is influenced by context-induced illusions of visual direction, while the sensorimotor system is not. Here, we inquire whether the process of making a spatially based decision is critical in forcing subjects to use the information in the cognitive system for spatial tasks. Subjects hear a tone that determines whether they jab an ''X'' or an ''O'' with the forefinger. Despite making a decision about which target to contact, the jab is not influenced by the position of a surrounding frame, indicating that choice can be handled within the context-insensitive sensorimotor system. (shrink)

Brain activity in the action observation network is lateralized during action execution, with greater activation in the contralateral hemisphere to the side of the body used to perform the task. However, it is unknown whether the AON is also lateralized when watching another person perform an action. In this study, we use fNIRS to measure brain activity over the left and right cortex while participants completed actions with their left and right hands and watched an actor complete action with (...) their left and right hands. We show that while activation is lateralized when the participants themselves are moving, brain lateralization is not affected by the side of the body when the participant is observing another person’s action. In addition, we demonstrate that individual differences in hand preference and dexterity between the right and left hands are related to brain lateralization patterns. (shrink)

Many previous treatments of voluntary behavior have viewed intentions as causes of behavior. This has resulted in several dilemmas, including a dilemma concerning the origin of intentions. The present article circumvents traditional dilemmas by treating intentions as constraints that restrict degrees of freedom for behavior. Constraints self-organize as temporary dynamic structures that span the mind-body divide. This treatment of intentions and voluntary behavior yields a theory of intentionality that is consistent with existing findings and supported by current research.

Actions shape what we see and memorize. A previous study suggested the interaction between motor and memory systems by showing that memory encoding for task-irrelevant items was enhanced when presented with motor-response cues. However, in the studies on the attentional boost effect, it has been revealed that detection of the target stimulus can lead to memory enhancement without requiring overt action. Thus, the direct link between the action and memory remains unclear. To exclude the effect of the (...) target detection process as a potential confounder, this study assessed the benefit of action for memory by separating items from the response cue in time. In our pre-registered online experiment, participants responded to visual Go cues by pressing a key or counting while ignoring No-go cues. In each trial, two task-irrelevant images were sequentially presented after the cue disappearance. After encoding the Go/No-go tasks, participants performed a surprise recognition memory test for those images. Importantly, we quantified the impact of overt execution of the action by comparing memories with and without motor response and the impact of covert motor processes by comparing memory between the motor and cognitive tasks. The results showed no memory differences between Go and No-go trials in the motor task. This means that the execution itself was not critical for memory enhancement. However, the memory performance in the motor No-go trials was higher than that in the cognitive No-go trials, only for the items presented away from the cues in time. Therefore, engaging the motor task itself could increase incidental memory for the task-irrelevant items compared to a passive viewing situation. We added empirical evidence on the online interaction between action and memory encoding. These memory advantages could be especially brought in action preparation and planning. We believe this fact may expand our present understanding of everyday memory, such as active learning. (shrink)

Bouts of exercise performed either prior to or immediately following study periods enhance encoding and learning. Empirical evidence supporting the benefits of interventions that simultaneously pair physical activity with material to be learned is not conclusive, however. A narrative, theory-based review of dual-task experiments evaluated studies in terms of arousal theories, attention theories, cognitive-energetic theories, and entrainment theories. The pattern of the results of these studies suggests that cognitive-motor interference can either impair or enhance memory of semantic information (...) and the manner in which physical activity impacts working memory within executive processing appears to explain disparate outcomes. The integration and timing of physical movements in concert with the type of information to be encoded and remembered appears to be a critical requirement for learning. These observations have implications for the role of physical activity in education, rehabilitation, and gerontological settings. (shrink)

The development of action representation during adolescence was investigated using a visually guided pointing motor task to test motor imagery. Forty adolescents and 33 adults were instructed to both execute and imagine hand movements from a starting point to a target of varying size. Reaction time was measured for both Execution and Imagery conditions. There is typically a close association between time taken to execute and image actions in adults because action execution and action simulation rely on (...) overlapping neural circuitry. Further, representations of actions are governed by the same speed-accuracy trade-off as real actions, as expressed by Fitts’ Law. In the current study, performance on the VGPT in both adolescents and adults conformed to Fitts’ Law in E and I conditions. However, the strength of association between E and I significantly increased with age, reflecting a refinement in action representation between adolescence and adulthood. (shrink)

Multitasking is a critical feature of our daily lives. Using a dual-task paradigm, this experiment explored adults’ abilities to simultaneously engage in everyday motor and cognitive activities, counting while walking, under conditions varying the difficulty of each of these tasks. Motor difficulty was manipulated by having participants walk forward versus backward, and cognitive difficulty was manipulated by having participants count forward versus backward, employing either a serial 2 s or serial 3 s task. All of these (...) manipulations were performed in single-task conditions and dual-task conditions. Both motor performance variables and cognitive variables were assessed in these conditions. Analyses of single-task conditions revealed that both motor and cognitive manipulations predictably influenced performance. Analyses of dual-task performance revealed influences of motor and cognitive factors on both motor and cognitive performance. Most centrally, dual-task costs for motor variables revealed that such costs occurred primarily for temporal or spatiotemporal gait parameters and were driven by cognitive manipulations. Dual-task cost analyses for cognitive measures revealed negative dual-task costs, or dual-task benefits, for cognitive performance. Finally, the effects of dual-task manipulations were correlated for motor and cognitive measures, indicating dual-task performance as a significant individual difference variable. These findings are discussed with reference to theories of attentional allocation, as well as the possible role of auditory–motor entrainment in dual-task conditions. (shrink)