Experimental Brain Research最新文献

{"title":"Transfer of learned object manipulations between two- and five-digit grasps.","authors":"Jordana Ulloa-Marquez, Jennifer Gutterman, Marco Santello, Andrew M Gordon","doi":"10.1007/s00221-025-07029-4","DOIUrl":"10.1007/s00221-025-07029-4","url":null,"abstract":"<p><p>Successful object manipulation involves integrating object properties into a motor plan and scaling fingertip forces through learning. This study investigated whether learned manipulations using a two-digit grip transfer to a five-digit grip and vice versa, focusing on the challenges posed by added degrees of freedom in force distribution. The goal of the task was to exert the necessary compensatory torque (Tcom) and vertical forces to minimize object roll on a visually symmetrical object that with an asymmetrical mass distribution. To examine this, subjects performed blocked consecutive learning trials before switching grip type. Our results support the learning transfer between two-digits and five-digit grasp configurations despite challenges in maintaining perfect stability during the grip switch. Subjects adapted their grip forces (GF), center of pressure (CoP), and Tcom to minimize object roll, with significant improvements observed from novel (1st) to transfer (11th) trials. These findings suggest high-level, effector-independent representations of object manipulation that enable generalization across grip types, though some limitations in force distribution and digit position arise during transfers.</p>","PeriodicalId":12268,"journal":{"name":"Experimental Brain Research","volume":"243 3","pages":"77"},"PeriodicalIF":1.7,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143498937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic interactions between discrete and rhythmic bimanual movement.","authors":"Remington Angel, Se-Woong Park","doi":"10.1007/s00221-025-07028-5","DOIUrl":"10.1007/s00221-025-07028-5","url":null,"abstract":"<p><p>Many motor tasks in everyday life, such as driving and cooking, involve a combination of discrete and rhythmic movements. While an increasing number of studies have identified discrete and rhythmic movements as fundamental components in complex motor control, the dynamic interactions between them remain elusive. This study aimed to quantify changes in kinematics when ongoing rhythmic movement of the right arm is perturbed by either rhythmic (RI) or discrete initiation (DI) of the left arm. Fourteen young adults (12 right-handed, 2 ambidextrous) performed bimanual forearm rotations on a horizontal plane under two conditions, i.e., RI and DI. We analyzed the change of instantaneous phase progression. Results showed that the perturbed magnitude and direction in the ongoing right arm were dependent on the relative phase between the two arms at the initiation of the left arm in both DI and RI. When observing the phase progression over the duration of the movement of discrete reaching, perturbations in the DI condition were comparable to those in the RI condition. However, over an extended duration beyond the discrete movement time, perturbations in the DI condition were significantly larger than those in the RI condition. The results suggest that, while the bimanual interaction appears consistent across the two types of movement, termination rather than initiation of discrete movements may engage distinct motor control processes compared to rhythmic movements.</p>","PeriodicalId":12268,"journal":{"name":"Experimental Brain Research","volume":"243 3","pages":"76"},"PeriodicalIF":1.7,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143482302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recreational older ballet dancers fall less with more effective reactive balance control than non-dancers after a slip during gait.","authors":"Caroline Simpkins, Feng Yang","doi":"10.1007/s00221-025-07021-y","DOIUrl":"10.1007/s00221-025-07021-y","url":null,"abstract":"<p><p>Recent work revealed that recreational ballet practice reduces older adults' fall risk after a standing-slip perturbation. However, whether such ballet practice can lead to decreased falls and better reactive motor control after a gait-slip among older adults remains unclear. This study investigated whether ballet reduces older adults' gait-slip falls and the possible neuromuscular and biomechanical mechanisms responsible for fall risk reduction. Protected by a safety harness, 15 older recreational ballet dancers and 21 age- and sex-matched non-dancers experienced a single unexpected slip while walking on a treadmill. The slip acceleration, duration, and displacement were standardized at 8 m/s², 0.2 s, and 16 cm, respectively. Motion and electromyography data were collected during the gait-slip trial. The outcomes included slip-faller rate as the primary outcome and the following secondary ones: dynamic gait stability, slipping foot displacement, recovery stepping performance, trunk movement, and recovery leg muscle electromyography latency (rectus femoris, biceps femoris, medial gastrocnemius, and tibialis anterior). The results revealed that fewer dancers fell after the gait-slip (p = 0.029). Dancers displayed better stability at recovery foot touchdown (p = 0.012), a longer (p = 0.002) and faster (p = 0.009) step, shorter slipping foot displacement (p = 0.031), less backward trunk velocity at touchdown (p = 0.011), and shorter latencies for all four muscles (p≤0.038). The results suggest that older dancers are more resilient to an unexpected gait-slip and display better reactive balance control responding to the slip perturbation, which could be related to their more effective recovery stepping, better trunk movement control, and faster leg muscle activations.</p>","PeriodicalId":12268,"journal":{"name":"Experimental Brain Research","volume":"243 3","pages":"75"},"PeriodicalIF":1.7,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143482426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Computational model for control of hand movement in Parkinson's disease using deep brain stimulation.","authors":"Maibam Pooya Chanu, Gajendra Kumar, Ramana Kumar Vinjamuri, Nayan M Kakoty","doi":"10.1007/s00221-025-07026-7","DOIUrl":"10.1007/s00221-025-07026-7","url":null,"abstract":"<p><p>Parkinson's disease (PD) is a progressive neurological disorder characterized by the loss of dopamine in the substantia nigra resulting in movement disorder. Although several computational models have been proposed to explore different aspects of PD, a comprehensive computational model of PD and its suppression remains elusive. This study presents a computational model of the Cortico-Basal Ganglia Thalamus (CBGT) network, and demonstrates the effects of close-loop deep brain stimulation (DBS) as a potential therapeutic intervention. The model focuses on addressing abnormal brain wave patterns associated with PD-related hand movement through DBS. To assess the model performance, a three-link manipulator is incorporated into the CBGT model, with the joints corresponding to shoulder, elbow and wrist of human arm. PD-like symptoms are simulated by modulating the dopaminergic input. The striatal (STR) neurons were selected as target neurons for application of DBS. A proportional-integral (PI) controller regulates DBS at different frequencies in striatal neurons based on errors in manipulator movement. The effectiveness of DBS at STR was compared with the DBS at globus pallidus externus and subthalamic nucleus. DBS suppressed neuronal signal oscillations at 13-30 Hz and reduced abnormal hand movements. The results demonstrate that application of DBS at STR could correct manipulator movement. Additionally, the trajectory of movement by the end-effector were compared with DBS at different target neurons in CBGT. These findings suggest the therapeutic potential of the proposed computational model in development of neuroprosthesis for PD patients.</p>","PeriodicalId":12268,"journal":{"name":"Experimental Brain Research","volume":"243 3","pages":"74"},"PeriodicalIF":1.7,"publicationDate":"2025-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143482088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Patterns of brain activity in choice or instructed go and no-go tasks.","authors":"Sanaz Attaripour Isfahani, Patrick McGurrin, Felipe Vial, Mark Hallett","doi":"10.1007/s00221-025-07027-6","DOIUrl":"10.1007/s00221-025-07027-6","url":null,"abstract":"&lt;p&gt;&lt;p&gt;The goal of this study was to investigate the decision making process for choosing what movements to make. We used electroencephalography (EEG) to investigate patterns of the contingent negative variation (CNV) associated with free-choice decisions to move or abstain, comparing them to conditions where actions were commanded. Our primary hypothesis was that choice tasks would differ significantly from each other and exhibit EEG patterns akin to their command-driven counterparts after the decisions were made, at least, in the 50 ms block of time prior to movement. A secondary analysis evaluated post hoc comparisons of time, in 50 ms blocks, to understand the temporal development of the CNV for each condition. We also conducted an exploratory analysis of EEG event-related desynchronization (ERD) to identify patterns of brain activity associated with the decision-making process. This approach was taken due to the exploratory nature of our hypotheses concerning the spatial and temporal characteristics of EEG activity during these free-choice versus commanded tasks. We studied 12 right-handed healthy volunteers (7 women, mean age 53 years, range 39-73 years) with no prior history of neurological or major psychiatric illness. A CNV paradigm encompassing commanded and choice tasks was devised, with a 2500 ms interval between S1 and S2, while recording EEG and electromyography (EMG). S1 provided full information about the upcoming task, which was to be executed at the time of S2. We assessed CNV and explored whole scalp EEG activity, including both voltage as well as power in the alpha and beta frequency ranges. Clear and similar CNVs were observed for command and choice go tasks prior to the movements, contrasting with near-zero CNVs for the command and choice no-go tasks. Separation of CNVs for command go and no-go tasks occurred around 1600 ms post-S1, and choice CNVs separated about 2150 ms post-S1. Exploratory analysis revealed that beta power provided information about decision and preparation processes much earlier. The left dorsolateral prefrontal cortex (DLPFC) exhibited the initial sign of decision approximately 500 ms post-S1 for all tasks, with subsequent preparation for movement or restraint involving distinct activity in various brain regions. The localization of effects in the left DLPFC was determined by visual analysis of the informative electrode sites. The CNVs separate about 2 s after S1, and it appears that this process represents preparation for movement (or no movement). Exploration of the beta activity suggests an earlier decision process which leads eventually to subsequent task preparation and activation. Choice decisions lag slightly behind command decisions, with the CNV apparently reflecting motor implementation rather than the decision-making process. In a simple motor task with an exploratory analysis, both commanded and choice-based decisions are rapidly initiated in the left DLPFC. While the CNV distinguishes betwee","PeriodicalId":12268,"journal":{"name":"Experimental Brain Research","volume":"243 3","pages":"73"},"PeriodicalIF":1.7,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11845411/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143467326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effector selection precedes movement specification: evidence from repetition effects in motor planning.","authors":"Christian Seegelke, Tobias Heed","doi":"10.1007/s00221-025-07022-x","DOIUrl":"10.1007/s00221-025-07022-x","url":null,"abstract":"<p><p>Motor performance is influenced by movements that were performed shortly prior. For example, reaction times (RTs) for successive movements are reduced when executed with the same effector, even if the specifics of the consecutive movements differ. These findings have been taken to support the notion that repetition effects in motor planning reflect the involvement of effector-specific motor plans. However, previous studies have confounded motor and visual aspects of repetition: movements have typically been instructed via visual cues, and movement repetition, therefore, implied repeating also the visual cue, so that the latter may be (at least partly) responsible for the observed RT effects. In the present study, participants performed two movements in succession, a prime and a probe action, either with their left or right hand and in one of two directions, inward or outward relative to the body midline. We used different cues for prime and probe actions, so that movement repetitions did not involve repetition of the visual cue. Participants initiated successive same-limb movements faster than different-limb movements, but this RT advantage was smaller than observed in previous work. Moreover, repeating movement direction also led to a decrease in RT, though only in combination with hand repetition. Whereas these findings imply that visual cue repetition can contribute to accelerated RTs in movement repetition, they confirm that the recent motor history affects motor planning. Furthermore, they support the idea of a hierarchical framework of motor planning in which effector selection precedes specification of motor parameters.</p>","PeriodicalId":12268,"journal":{"name":"Experimental Brain Research","volume":"243 3","pages":"71"},"PeriodicalIF":1.7,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11842427/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143457328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correlates of gait speed changes during uneven terrain walking in older adults: differential roles of cognitive and sensorimotor function.","authors":"Valay A Shah, Yenisel Cruz-Almeida, Arkaprava Roy, Erta Cenko, Ryan J Downey, Daniel P Ferris, Chris J Hass, Patricia A Reuter-Lorenz, David J Clark, Todd M Manini, Rachael D Seidler","doi":"10.1007/s00221-025-07019-6","DOIUrl":"10.1007/s00221-025-07019-6","url":null,"abstract":"<p><p>Many studies of walking function and aging have measured walking on flat surfaces with and without dual-tasking (i.e., performing a concurrent cognitive task). Walking in the community increases the complexity with surface undulations and varying surface types. We hypothesized that changes in walking resulting from increasing terrain unevenness would be better predicted by sensorimotor function than cognitive function. Sixty-three community-dwelling older adults (65-93 yrs old; 32 males) performed overground walking under four uneven terrain conditions (Flat, Low, Medium, and High unevenness). Cognitive (cognitive flexibility, working memory, inhibition) and sensorimotor assessments (grip strength, 2-pt discrimination, pressure pain threshold) were measured as the primary predictors of walking performance. We found that walking speed decreased linearly with more elevated uneven terrain conditions across all participants; this was accentuated in older adults with lower mobility function. Greater rates of decline in walking speed from flat to uneven terrain were associated with worse attention and inhibitory function as well as lower 2-point tactile discrimination. Findings suggest that greater rates of decline with elevated terrain walking are associated with lower mobility function, lower executive functions and less somatosensation.</p>","PeriodicalId":12268,"journal":{"name":"Experimental Brain Research","volume":"243 3","pages":"72"},"PeriodicalIF":1.7,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143457327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Covariation of corticospinal excitability and the autonomous nervous system by virtual reality: the roller coaster effect.","authors":"Sidney Grosprêtre, Johanna Mathiot, Pauline Eon, Célia Ruffino","doi":"10.1007/s00221-025-07015-w","DOIUrl":"10.1007/s00221-025-07015-w","url":null,"abstract":"<p><p>Virtual Reality (VR) is a computer simulation of a three-dimensional environment, often displayed by means of a headset with integrated screens. While VR is known to consistently stimulate the autonomic nervous system, little is known regarding a possible effect on corticospinal excitability, or regarding a potential link between autonomous and voluntary nervous system modulations during VR. Fifteen healthy young participants were enrolled in a single-session experiment. They were seated in a comfortable chair and equipped with a VR headset that displayed a simulated roller coaster ride. Galvanic Skin Response (GSR) and cardiovascular markers (heart rate, heart rate variability) were monitored throughout the experiment. Corticospinal excitability was quantified by measuring the amplitude of the motor evoked potential (MEP), elicited by transcranial magnetic stimulation on the cortical representation of the right First Dorsal Interosseous (FDI) muscle. Results showed modulation in skin conductance, according to the phase of the roller coaster. Corticospinal excitability was increased during downhill and decreased during uphill phases, as compared to flat sections. The evolution of MEP/Mmax was concomitant and correlated to the evolution of GSR. No effect was observed on any of the cardiovascular markers. The present study showed that VR can be an efficient stimulus to modulate corticospinal excitability, even in the absence of a motor simulated situation. These data suggest a potential link between voluntary and autonomic nervous system regulation during VR of stressful situations. This study highlights the attractiveness of VR as an efficient stressor for both autonomous and motor systems, in sport training and in rehabilitation.</p>","PeriodicalId":12268,"journal":{"name":"Experimental Brain Research","volume":"243 3","pages":"69"},"PeriodicalIF":1.7,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143440418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Can visual acceleration evoke a sensation of tilt?","authors":"Laurence R Harris, Björn Jörges, Nils Bury, Meaghan McManus, Ambika Bansal, Robert S Allison, Michael Jenkin","doi":"10.1007/s00221-025-07023-w","DOIUrl":"10.1007/s00221-025-07023-w","url":null,"abstract":"<p><p>Under the microgravity of the International Space Station, many of the normal processes that determine the perceptual upright on Earth are disrupted. For example, somatosensory cues are absent and an applied physical linear acceleration can provide an artificial \"gravity\" reference. Here, we hypothesized that visual linear acceleration could also be interpreted as an orientation cue in microgravity. Using virtual reality, we subjected twelve astronauts experiencing long-duration exposure to microgravity to visually simulated accelerating linear self-motion along a virtual corridor at 0.8 m•s^- 2 (0.083 G) for 16s. They then adjusted a virtual ground plane to indicate whether they had changed their perceived orientation. Control experiments used visually simulated linear self-motion at a constant velocity and control experiments on Earth mirrored the experiments conducted in microgravity in both upright and supine postures. Contrary to our hypothesis, no significant perceptual tilts were induced on Earth or in microgravity. However, we did replicate earlier results that both microgravity exposure (in comparison to on Earth) and a supine posture (in comparison to a sitting upright posture) were associated with higher variability in judgements of upright. Our experiments failed to demonstrate that exposure to visual acceleration can evoke a sense of tilt in a stationary observer in the dark, either in microgravity or on Earth.N = 209.</p>","PeriodicalId":12268,"journal":{"name":"Experimental Brain Research","volume":"243 3","pages":"68"},"PeriodicalIF":1.7,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143440417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Glioblastoma induced blood-brain barrier dysfunction via a paracrine mechanism that increases claudin-1 expression.","authors":"Brittany Schweiger, Forrest M Kievit","doi":"10.1007/s00221-025-07018-7","DOIUrl":"10.1007/s00221-025-07018-7","url":null,"abstract":"<p><p>Blood-brain barrier (BBB) disruption is a well-known phenomenon in glioblastoma (GBM). However, the mechanism driving BBB dysfunction in previously established vasculature at the invasive edge of GBM is still unknown. In this study, we aimed to determine if GBM paracrine signaling is sufficient to induce BBB dysfunction and identify changes in the tight junctions of the BBB. An in vivo U-87 MG xenograft model and an in vitro primary brain endothelial cell BBB model were established for barrier dysfunction monitoring. Immunofluorescent staining revealed significantly higher claudin-1 expression and significantly lower claudin-5 expression in the tumor vs. normal brain tissue of our in vivo model (p < 0.01). Additionally, claudin-1 expression co-localized with brain cell type markers for endothelium, pericytes, and microglia. In vitro exposure of brain microvascular endothelial cells to GBM conditioned media resulted in a significant decrease in transendothelial electrical resistance as well as delocalization of claudin-5 from the tight junctions. These results suggest GBM cells secrete factors capable of inducing changes in the tight junction proteins of the BBB and decreasing barrier integrity. Future studies will aim to identify the mechanism in which these changes occur.</p>","PeriodicalId":12268,"journal":{"name":"Experimental Brain Research","volume":"243 3","pages":"70"},"PeriodicalIF":1.7,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143440427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}