Neural Representations of Perceived Engagement during Action Observation.

Mild cognitive impairment (MCI) is a precursor state of Alzheimer's disease (AD) and has attracted attention, but why amnestic mild cognitive impairment (aMCI) is more likely to progress to AD than non-amnestic mild cognitive impairment (naMCI) is unclear. The present study of aMCI compares differences in intra- and inter-network functional connectivity (FC) across multiple networks in naMCI and further correlates FC with cognitive assessment scores to assess their ability to predict AD progression. Resting-state functional magnetic resonance imaging (rs-fMRI) was performed in 30 naMCI and 40 aMCI cases, and 12 resting-state networks (RSNs) were identified by independent component analysis (ICA). Two-sample t-tests were performed to detect intra-network FC differences, and functional network connectivity (FNC) was calculated to compare inter-network FC differences. Subsequently, Pearson or Spearman correlation analyses were used to explore the correlation between altered FC and cognitive assessment scores. The aMCI compared to the naMCI differed within the (Default mode network) DMN, (Dorsal attention network) DAN, (Sensorimotor system) SMN, and (Salience network) SN networks (corrected for FWEc, P< 0.05), and inter-network differences in DAN-DMN, DMN-SN, SN-SMN (corrected for FWEc, P<0.05). aMCI contrasts naMCI with widespread intra- and inter-static FNC differences, mainly involving the DMN, DAN, SMN, and SN. these network interactions provide a powerful method for assessing and predicting why aMCI is more likely to progress to AD, and contribute to our understanding of the neurological mechanisms underlying the pathological process of AD.

How prior motor states can shape perceptual decision bias: Insights from sensorimotor beta oscillations.

The unique human ability to process complex language requires the interaction of multiple brain areas located in the inferior frontal and posterior temporal cortex connected by white matter fiber tracts. These fiber tracts underlie the transfer of information between brain regions. In recent years, MRI of white matter brain networks has provided important insights into the plasticity of the structural brain basis underlying language. This structural network is shaped during childhood as a function of language learning by strengthening the connectivity between language-relevant regions mainly in the left hemisphere. In this way, the specific linguistic properties of the native language tongue lead to a modulation of the core language network observable in the adult brain. The brain basis underlying language processing also changes when a second language is learned, as shown by differences in brain connectivity between bilingual and monolingual individuals and by dynamic adaptations during second language learning. Studies of people who use sign language as their native language have shown a domain specificity of the sensory and motor systems rather than the core language network. This separation of the core language system from the sensory-motor system is evolutionarily based. Although the basic auditory-motor interface system is also present in monkeys and apes, the core language system reveals key differences between humans and nonhuman primates. Understanding the function and plasticity of this network is of paramount importance for human cognitive processes, including development and developmental disorders.

Axial loading as a countermeasure to hypogravitational disorders in sensory-motor system

Premature aging and neuropathic behaviours induced by an acute low-dose exposure to a sarin surrogate.

Background: Although tone acquisition is one of the most challenging aspects for adult second language (L2) learners, research remains limited on how learners from non-tonal first language (L1) backgrounds develop across proficiency levels. The current study examined Mandarin disyllabic tone sequences produced by learners at three proficiency levels. Methods: This study recorded the Mandarin tone production of beginner, intermediate, and advanced Korean learners and evaluated their accuracy and error patterns to determine whether similarities between L1 and L2 prosodic systems affect tone sequence difficulty. Results: Across groups, tone sequence rankings were consistent, differing mainly in accuracy rates. Learners showed an advantage in producing sequences aligned with Korean tonal patterns, such as T1–T1 and T3–T1, which were the easiest to produce. In contrast, sequences without Korean counterparts, particularly those ending in T2, remained the most difficult at all proficiency levels. Conclusions: Neurolinguistic evidence suggests that tones lacking L1 motor representations are disadvantaged by limited motor templates and weaker auditory coding, which together account for persistent difficulty with T2 sequences. Interestingly, T2 in word-initial position improved with experience, as increased exposure and practice helped learners form new sensorimotor routines supported by strengthened auditory–motor coupling. Over time, such experience-dependent neural reorganization enables more precise execution of rising F0 movements when tones occur at the beginning of a sequence, whereas carry-over interference from preceding tones continues to hinder accuracy in word-final position. This study provides insight into how sensorimotor and auditory systems interact in L2 tone learning, offering a neurocognitive framework for understanding prosodic transfer.

ABSTRACT Semantic learning of action-related words (e.g. cut, kick) was modelled in brain-constrained neural networks fashioned according to the neuroanatomical structure of relevant parts of the human cortex. These networks were applied to simulate infants uttering action words when performing related actions, where word meaning is learnt and grounded in the world. During learning neuronal circuits emerged each interlinking information about a word form and its related action type, so that word form perception-simulation in the network brought about immediate activation of semantically-related action information. We discuss this model in view of established evidence from cognitive neuroscience and argue that a mechanism similar to the network’s word-action associations and resultant topographically-organised memory representations may provide the biological basis of understanding and mentalising action-related concepts in humans. Further, the results shed light on how perceptual and action-related information may shape the structure of semantic circuits across cortical areas.

The present study investigates how the sensorimotor and semantic systems influence object processing. Participants selected images labeled as tools or nontools using a large mouse which requires power grip or a small mouse which requires precision grip. The upright and rotated objects were presented to induce stable and variable affordances, respectively. Response times and both temporal and spatial indicators of mouse movement trajectory were recorded. The processing advantage observed when an object's motion representation congruent with the mouse response, compared to the incongruent condition, is termed as the compatibility effect. Our findings revealed that graspable nontools resembling tools could also activate affordances. Critically, the stable affordances rely on long-term memory representations of object knowledge, while variable affordances depend on online processing of immediate visual or sensory cues, emphasizing the interaction between conceptual and motor systems in object processing. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

Alzheimer’s disease (AD) is characterized by progressive disruptions in large-scale brain networks that precede cognitive decline, yet conventional functional connectivity analyses often fail to detect disruptions in coordination among large-scale brain networks that may be critical for early detection. This study leverages quasi periodic patterns (QPPs) and complex principal component analysis (cPCA) to characterize spatiotemporal network alterations across longitudinally stable (normal cognitive, mild cognitive impairment, dementia of Alzheimer’s type) and transitioning (normal cognitive to mild cognitive impairment, mild cognitive impairment to dementia of Alzheimer’s type) cohorts from the Alzheimer’s Disease Neuroimaging Initiative using resting state fMRI. QPPs were used to derive recurrent spatiotemporal templates and network integrity measures at the intrinsic connectivity network level, while cPCA decomposed Hilbert transformed time series into complex valued patterns that capture amplitude and phase relationships. Nonparametric group comparisons revealed a structured trajectory in which limbic, subcortical, and higher cognition networks, including triple network components, are affected early, followed by progressive disruption in visual, cerebellar, sensorimotor, and additional triple network systems. Transitioning cohorts showed many of these alterations before formal diagnostic conversion, indicating that spatiotemporal signatures carry preclinical information. QPP based metrics were particularly sensitive to limbic and subcortical degradation, whereas cPCA emphasized changes in higher order, visual, and cerebellar patterns, revealing complementary aspects of the same underlying pathology. These findings extend prior QPP only work and highlight the utility of combining QPP and cPCA based measures as a dynamic, network-level biomarker framework for AD progression. with potential applications in early detection, characterizing disease trajectories, and treatment monitoring.

Humans have exceptional object manipulation skills. By combining feed-forward and feedback control, the sensori motor system is able to predictively scale grip and manipulation forces and quickly adapt to environmental changes. Using technologies such as virtual reality, researchers can investigate the underlying mechanisms in ways that are not possible in the physical world. Here, we present our custom-built virtual reality setup, including an open-source software framework, and show its validity in human motor control studies. We replicated two well-established experiments involving physical objects that investigated how humans adapt to different object mass and center of mass. Our results show that the general force and position control strategies employed in the virtual experiment closely mirrored those observed in the real world. Specifically, participants scaled grip forces with object mass and coordinated digit positions and forces according to the object's center of mass and shape. However, the trial-by-trial adaptation rate was slower, and the grip forces were slightly increased in the virtual setup, likely due to increased uncertainty arising from the 2D visual feedback and the lack of cutaneous feedback. Additionally, we tested the effect of visual feedback complexity by comparing a simple and detailed representation of the fingers, finding that participants exhibited similar manipulation strategies across both conditions. Our results validate this setup as a reliable platform for future studies in human motor control.

Chronic pain is increasingly recognized as a brain-based condition sustained by maladaptive neuroplasticity rather than persistent nociceptive input alone. This review integrates structural, functional, and connectomic evidence to examine how chronic pain reorganizes neural circuits involved in sensory processing, emotional regulation, cognitive control, and motivational learning. Findings from neuroimaging studies consistently demonstrate gray matter volume alterations, white matter microstructural changes, aberrant task-evoked activity, and disruptions in resting-state networks such as the default mode, salience, and sensorimotor systems. Predictive markers—including corticostriatal connectivity, corticolimbic anatomy, and prefrontal regulatory capacity—suggest that emotional reinforcement patterns and diminished cognitive modulation contribute to the transition from acute to chronic pain. These mechanisms highlight chronic pain as a self-reinforcing neural state shaped by interactions between sensory, cognitive, and affective processes. The review underscores the need for mechanism-based, interdisciplinary clinical approaches and emphasizes the relevance of these findings for diverse healthcare settings, particularly in Latin America. Future work should prioritize longitudinal, multimodal investigations to refine biomarker candidates and support personalized, neuroplasticity-informed interventions.

Unveiling the sensorimotor basis of numerical processing: A functional near-infrared spectroscopy (fNIRS) study.

Impact of age on gait parameters under motor and cognitive dual-task conditions.

IntroductionThe Research Domain Criteria (RDoC) approach initiated by the National Institute of Mental Health provides a comprehensive framework for guiding research on mental illness and health. Since retrospective studies have indicated associations between RDoC characteristics and clinically relevant as well as care-relevant outcomes, there is a need for prospective, theory-driven investigations that systematically link a priori defined assessments of RDoC constructs to clinically and care-relevant outcomes in a transdiagnostic psychiatric sample.Methods and analysisThis prospective observational study assesses six domains—Positive Valence Systems, Negative Valence Systems, Cognitive Systems, Social Processes, Arousal and Regulatory Systems and Sensorimotor Systems—employing a comprehensive set of self-report and additional paradigms to assess cognitive functioning developed a priori in alignment with the RDoC framework while also assessing clinically and care-relevant variables (eg, length of hospital stay). A total of 300 adult participants will be recruited among in- and outpatients of two psychiatric hospitals in Germany (patient group) as well as from the general population (healthy control group). Including healthy individuals will allow for the investigation of continuous variations in psychological functioning rather than categorical distinctions between health and disease. Data collection includes self-reports, clinician ratings, file review and behavioural assessments. Electroencephalography is recorded in a subgroup of participants. A confirmatory factor analysis will be conducted to reproduce the factor structure and regression models will be used to investigate associations between RDoC domains and clinically relevant as well as care-related variables.Ethics and disseminationEthics approval was obtained from the local ethics committee of the Brandenburg Medical School—Theodor Fontane (E-01-20220822). Results will be disseminated through peer-reviewed journals and academic conferences.

Objective.Implanted electrodes for nerve stimulation and myoelectric recording facilitate bidirectional sensory feedback and control for neuromuscular conditions such as limb loss. While increasing implanted electrode channel count offers potential benefits, it also presents engineering and implementation challenges. This case study examines how increasing implanted electrode channel count affects sensory perception and myoelectric controller performance, thereby supporting the value of these advancements.Approach.One participant with upper extremity transradial limb loss received a percutaneous implanted system with two 8-channel extraneural cuff electrodes on the median and ulnar nerves, totaling 16 stimulating channels. The individual later received a wirelessly connected implanted system featuring four 16-channel extraneural cuff electrodes on the median, ulnar, and radial nerves, totaling 64 stimulation channels, and four tetra-intramuscular (TIM) recording electrodes in residual muscles, totaling 32 sensing channels configured into 16 bipolar pairs. To compare sensory perception between the 16- and 64-channel stimulation systems, we assessed cumulative percept location coverage and the number of unique percept locations, estimated through hierarchical clustering. We compared performance across three myoelectric control algorithms that mapped 8, 10, or 14 intramuscular signal inputs through an artificial neural network to control a virtual hand in 4 degrees-of-freedom (DOFs), with simultaneous, independent, and proportional control.Main results.Increasing stimulation channel count expanded cumulative percept location coverage and increased the number of unique percept locations on the hand. Adding intramuscular recording channel inputs improved 4-DOF myoelectric control of a virtual hand, increasing target posture match percentage and path efficiency.Significance.This case study demonstrates that increasing the number of implanted electrodes can advance sensory restoration and myoelectric control for bidirectional upper limb prostheses. Continued development of more complex systems with higher channel counts may further improve outcomes for individuals with limb loss and enhance the function of sensorimotor restoration systems.Trial registration:ClinicalTrials.gov ID: NCT04430218, 2020-06-30.

Neural underpinnings of visuomotor adaptation and retention after a night of sleep in children with DCD.

μ Opioid Modulation of Sensorimotor Functional Connectivity in Autism: Insights From a Pharmacological Neuroimaging Investigation Using Tianeptine

BackgroundA biological model of auditory learning posits that the auditory cortex interacts with the cognitive, sensorimotor, and reward systems to improve sound learning in real-world listening. Congenital amusia is a neurodevelopmental disorder characterized by deficits in fine-grained pitch discrimination. Although previous studies have investigated the auditory processing, sensorimotor and cognitive abilities of amusia, the characteristics of musical reward in amusia remain unclear.MethodWe recruited 44 individuals with congenital amusia (22 females; 19.66 ± 1.92years), identified with the Montreal Battery of Evaluation of Amusia (MBEA; cut-off ≤ 21.5) and 44 matched controls(23 females; 19.61 ± 1.65years). Participants completed the Barcelona Music Reward Questionnaire(BMRQ) to assess derived pleasure from engagement in musical activities, and the Multiple Mood Scale (MMS) to evaluate emotional experiences (heightened, tragic, romantic, blithe) elicited by minor- and major-key music.ResultsThe amusia group reported lower overall BMRQ scores and lower scores on all five BMRQ subscales (social reward, mood regulation, emotional evocation, sensory-motor and musical seeking) compared to controls. For the musical emotion task, both groups experienced similar musical emotions for major music, whereas the amusia group rated minor-key music as significantly less tragic and more blithe. Additionally, overall BMRQ scores were negatively associated with blithe and heightened ratings for major-key music, whereas these associations were positive in controls.ConclusionsThese findings suggest individuals with amusia exhibit music-specific deficits in the pleasure derived from music, together with an alteration in emotion experience to minor-key music. Overall, the findings indicate an alteration in the use of pitch-derived cues when evaluating musical emotions and their relation to reward. From a reward perspective, these findings guide neuroimaging studies toward clarifying how pitch-based cues influence music-induced emotion experiences in congenital amusia.Supplementary InformationThe online version contains supplementary material available at 10.1186/s40359-025-03664-2.

Local muscle vibrations (LMV) acutely and chronically affect the sensorimotor system, but their effects vary depending on application conditions. The mechanisms behind repeated LMV exposure are still debated. This study investigated the chronic effects of LMV under illusion-inducing conditions on the upper limb. Nineteen healthy participants completed 9 LMV sessions (80 Hz, 20 min) over 11 days targeting the right wrist flexors. Illusions were assessed using subjective scales and EEG (alpha band desynchronization). Neurophysiological parameters (spinal, corticospinal excitabilities, and intracortical inhibition) and grip strength were evaluated before and after a control session (20-min rest) and an LMV session, as well as after 9 LMV sessions and 5 days post-protocol. Participants consistently experienced illusions throughout the protocol, with stronger perceptions during the first 15 min. However, subjective and objective measures were found to be independent. Acute LMV significantly reduced the H-reflex (-52.3% [-69.7 ; -21.0]) but did not affect strength or other neurophysiological measures. Additionally, repeated LMV exposure induced no chronic changes in strength or neural excitabilities and inhibition. While confirming acute LMV effects under illusion conditions, this study found no evidence of chronic adaptations. It also suggests that subjective and objective (EEG-based) illusion measures reflect distinct neurophysiological mechanisms.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-26915-z.