Biology subjects

Bestmann, S.

Publications and source records attributed to Bestmann, S..

At least 19 recordsLinked to original sources

bioRxiv2026

Forward Modelling for Magnetospinography: Systematic Comparison of Boundary Element and Finite Element Methods

Magnetospinography (MSG) enables non-invasive measurement of spinal cord electrophysiology, but accurate interpretation of these signals depends critically on forward modelling assumptions. We compared four vertebral bone representations: continuous, homogeneous-toroidal, inhomogeneous-toroidal, and MRI-derived-realistic, implemented within both boundary element method (BEM) and finite element method (FEM) frameworks. Lead-fields were computed across the full spinal cord for three orthogonal source orientations. When comparing matched model pairs, BEM and FEM produced consistent forward solutions, with median relative errors below 3.1% and median squared correlation coefficients exceeding 0.998 across all bone geometries. Vertebral bone geometry exerted a systematic and orientation-dependent influence on predicted lead fields. The dominant distinction was between continuous and segmented bone representations rather than between simplified and anatomically detailed segmented models. For left-right oriented sources, segmented geometries produced substantially higher field amplitudes (fT/nAm) than the continuous model throughout the cord (35-72%), while toroidal and MRI-derived realistic models produced comparable results across both frameworks, with median r2 exceeding 0.97 between segmented models compared to 0.67-0.85 for continuous versus segmented comparisons. Sensor placement further modulated sensitivity profiles, with posterior arrays exhibiting greater sensitivity lower down the cord, but anterior and posterior sensors showing comparable sensitivity in the cervical region.

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bioRxiv2026

Theta phase and theta-gamma coupling organise the spoken language network

Speech production requires rapid coordination of conceptual and lexical processes across distributed cortical networks, yet the neurophysiological mechanisms enabling this coordination remain poorly understood. Oscillatory coupling has emerged as a candidate mechanism for coordinating neural activity across spatial scales. Here, we used whole-head magnetoencephalography during overt picture naming to test how phase and phase-amplitude coupling organise neural dynamics preceding articulation. We show that theta (4-8 Hz) phase coupling increases within two functionally distinct networks: a ventral occipito-temporal network supporting object recognition and a medial fronto-temporal network supporting semantic-lexical retrieval. These networks converged in the right fusiform gyrus beyond chance levels, identifying a candidate integration hub. In parallel, whole-brain analysis of theta-gamma (4-8 Hz, 40-100 Hz) phase-amplitude coupling revealed selective increases in the left inferior frontal and fusiform gyri during picture naming relative to control. Mixed-effects modelling further showed that coupling in the left fusiform correlates with trial-level response times during naming but not control trials. Together, these findings reveal the oscillatory mechanisms that implement known functional specialisation in the spoken language network; theta phase coupling coordinates distributed recognition and retrieval streams, while theta-gamma coupling modulates local computations within core word production nodes. By defining an oscillatory framework for real-time speech production, this work advances mechanistic understanding of the spoken language network and identifies frequency- and region-specific targets for neuromodulation of language production disorders. HighlightsO_LIDistinct oscillatory mechanisms support distributed and local language production processes C_LIO_LITheta phase-coupling distinguishes object recognition and word retrieval networks C_LIO_LITheta-gamma coupling increases locally in core language regions C_LIO_LIIncreases in theta-gamma coupling scale with trial-by-trial naming speed C_LI

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bioRxiv2026

TMS-Evoked Corticospinal Beta Oscillations in Humans Recorded from Muscles

BackgroundTranscranial magnetic stimulation (TMS) can entrain oscillatory brain activity, offering a promising approach to study motor-related neural oscillations such as beta rhythms. However, how TMS-induced corticospinal oscillations are generated, propagated, and related to endogenous activity remains unclear, partly due to limitations in brain recording techniques. Recording muscle activity provides an alternative and physiologically grounded window into corticospinal dynamics. MethodsWe investigated whether subthreshold TMS over the motor cortex induces corticospinal oscillatory activity detectable in muscles, and whether these responses share neural generators with endogenous beta rhythms. Single-pulse subthreshold TMS was applied over the motor cortex in healthy participants while electromyography (EMG) was recorded from tonically active muscles. Stimulation intensity, coil orientation, and stimulation site were systematically varied. Concurrent electroencephalography (EEG) was used to assess cortical responses and corticomuscular transmission. In additional experiments, advanced EMG techniques were employed to track motor neuron pools and characterize how TMS-evoked oscillations are transmitted at the motor unit level. ResultsTMS elicited a robust and short-latency increase in beta-band activity in the EMG. The analysis of the elicited muscle responses and the comparison of results across different TMS configurations indicate that the beta responses resulted from activation of inhibitory interneurons in the targeted primary motor cortex. Importantly, the characteristics of cortico-muscular coherence and beta projection to the muscles indicate that the elicited beta responses with TMS have same cortical sources as endogenously generated beta activity. ConclusionsThese findings demonstrate that muscle recordings provide a sensitive and physiologically meaningful readout of TMS-induced corticospinal beta oscillations.

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bioRxiv2026

Expert Motor Synergies Emerge Predominantly Offline During Early Skill Learning

Everyday skilled actions depend on the formation of coordinated motor synergies that integrate multiple digits into stable, low-dimensional control units. Although initial practice of a new skill leads to rapid performance improvements, it is unclear whether the underlying movement kinematics reorganize on a similar timescale and in a way that directly relates to these gains. It also remains uncertain whether such reorganization occurs mainly during active practice or instead during brief rest breaks. Here, we tracked the temporal evolution of multi-digit synergy formation during early learning of a naturalistic keypress skill. Initial practice rapidly sculpted the motor repertoire toward higher-order, temporally compressed and overlapping multi-digit synergies. These synergies emerged after only minutes of practice and continued to be expressed along the full training session. Notably, they were primarily shaped across brief rest breaks and robustly predicted individual skill proficiency. Across learning, distinct synergy subtypes emerged, differing in their heuristic prevalence. Rarely expressed synergies reflected transient novice patterns, synergies expressed at intermediate levels could index exploratory and trial-initiation strategies, and highly expressed synergies emerged later to dominate performance, reflecting the consolidation and expansion of skilled motor control. Together, these findings indicate that skilled performance is supported by the early formation of a compact repertoire of expert multi-digit synergies that emerge preferentially across rest periods and predict subsequent skill gains. They further raise the hypothesis that explicitly training such expert synergies alongside task goals could enhance learning in domains such as the arts, sport, and neurorehabilitation. HighlightsExpert multi-digit synergies form during early skill learning Higher-order synergies emerge across brief rest breaks Fatigue spares expert synergy use during early learning Skill gains mirror multi-digit synergy expression eTOC blurb"Expert multi-digit synergies emerge early in motor learning, strengthen across brief rest breaks, track skill gains, and resist fatigue"

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bioRxiv2025

The Cerebellum Implements an Oscillatory Forward Model for Accurate Motor Timing

Voluntary movements are composed of small sub-movements generated by pulsatile bursts of muscle activity at 4-10 Hz. These motor intermittencies synchronize with rhythmic brain activity and vary with movement velocity and sensory delays, suggesting they are a signature of a central oscillatory motor control mechanism. We hypothesized that these pulsatile movements arise from a cerebellar clocking mechanism-a neuronal timing process that flexibly adjusts its dynamics to maintain motor precision under temporal uncertainty. If so, cerebellar rhythms should modulate their influence on movement depending on cue predictability. To test this, we used optically pumped magnetoencephalography (OP-MEG), which enables high-quality, movement-tolerant recordings of the brain with dense cerebellar coverage. Six participants performed an auditory-paced finger flexion-extension task at approximately 1 Hz with either regular or irregular cue timing to vary predictability. All participants exhibited clear 4-10 Hz intermittencies in their kinematics, synchronized to neural activity in the cerebellum and the posterior parietal cortex. Our connectivity analysis revealed for the first time, that cerebellar activity at this frequency, predominantly reflects sensory feedback, but during regular, predictable cueing, the cerebellum shifts to exert a greater feedforward influence on movement. Moreover, cerebellar oscillations were most persistently phase-aligned with motor intermittent rhythms during accurately timed actions, an effect that was absent under irregular cueing. These findings support the idea that the cerebellum implements an oscillatory forward model for motor timing and provide novel evidence for its ability to adjusting its role in coordinating sensorimotor integration according to sensory predictability. Motor intermittencies may thus represent the output of a cerebellar timing process that underpins precise voluntary action.

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bioRxiv2025

Beyond deep versus superficial: true laminar inference with MEG

Neural dynamics at the laminar level are critical for cortical computation. However, in humans, non-invasive methods to probe such dynamics have been limited to coarse distinctions between deep and superficial layers. Here, we present a multilayer magnetoencephalography source reconstruction framework and evaluate the conditions under which depth-resolved laminar inference may be feasible. Using simulations, we systematically assess the limits of magnetoencephalography depth resolution, showing that laminar discrimination depends on sufficiently high signal-to-noise ratio, precise co-registration, and accurate specification of cortical column orientation. We demonstrate that regional variations in cortical anatomy influence reconstruction fidelity, with lead-field separability emerging as a key determinant. We then apply this framework to empirical data from three independent datasets and find laminar activation patterns that align with canonical feedforward and feedback motifs in visual and sensorimotor circuits, supporting the plausibility of laminar inference under favorable conditions and offering opportunities to bridge invasive electrophysiology and human neuroimaging.

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bioRxiv2025

Wearable MEG data recorded during human stepping

Non-invasive spatiotemporal imaging of brain activity during large-scale, whole body movement is a significant methodological challenge for the field of movement neuroscience. Here, we present a dataset recorded using a new imaging modality - optically-pumped magnetoencephalography (OP-MEG) - to record brain activity during human stepping. Participants (n=3) performed a visually guided stepping task requiring precise foot placement while dual-axis and triaxial OP-MEG and leg muscle activity (electromyography, EMG) were recorded. The dataset also includes a structural MRI for each participant and foot kinematics. We validate the fidelity of the OPM data by showing movement-related beta band desynchronization source localised to the primary motor cortex. This multimodal dataset offers a resource for methodological development and testing for OPM data (e.g., movement-related interference rejection), within-subject analyses, and exploratory analyses to generate hypotheses for further work on the neural control of human stepping.

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bioRxiv2024

Failed Double-Blind Replication of Offline 5Hz-rTUS-Induced Corticospinal Excitability

IntroductionTranscranial ultrasound stimulation (TUS) is a promising new form of non-invasive neuromodulation. As a nascent technique, replication of its effects on brain function is important. Of particular interest is offline 5Hz repetitive TUS (5Hz-rTUS), originally reported by Zeng and colleagues [1] to elicit lasting corticospinal excitability increases, with large effect sizes. Material and methodHere, we conducted a pre-registered (https://osf.io/p5n4q) replication of this protocol that benefitted from three additional features: double-blind application of TUS, neuronavigation for consistent TMS positioning, and acoustic simulations to assess M1 target exposure to TUS. Changes in resting motor thresholds (rMT), motor-evoked potential (MEP) amplitude, short-interval intracortical inhibition (SICI) and intracortical facilitation (ICF) in response to TUS (5Hz-rTUS vs. sham) were measured in the right first dorsal interosseous (FDI), abductor digiti minimi (ADM) and abductor pollicis brevis (APB) muscles, with unbiased selection of participants. Transducer location was determined by the TMS-hotspot for motor representations of the right FDI, as in the original work. ResultsNo significant effects of 5Hz-TUS (vs sham) were observed. Post-hoc simulations showed considerable variability of the acoustic focus, which was outside the anatomical M1-hand area in 67% of participants - in line with the known poor correspondence of TMS-hotspot location and M1-hand area. ConclusionOur results indicate that the effect sizes of the neuromodulatory effects of 5Hz-rTUS on M1 may be more variable than previously appreciated. We suggest that double-blinding, neuronavigated TMS, individualised acoustic simulations for TUS targeting and pre-registration will aid reproducibility across studies.

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bioRxiv2024

Use of the non-paretic arm reflects a habitual behaviour in chronic stroke

BackgroundA proportion of stroke survivors use their affected arm less than might be expected based on their level of impairment. The resulting non-use of the affected arm has a negative impact on participation in neurorehabilitation and functional independence. However, non-use remains poorly understood. One possibility is that prioritising the non-paretic arm reflects a habit, despite residual functional capacity in the paretic arm. Methods30 chronic stroke survivors (Mean FM: 28.9 {+/-} 11.3) participated in a simplified version of the forced response paradigm, which reliably identifies the presence of a habit. Participants were asked to choose which arm to use to maximise points scored during a reaching task. During half of the trials, the presumed habit of using the non-paretic arm yielded more points, whereas in the other half using the non-paretic arm incurred a loss of points. Participants completed two versions of this task, once with unlimited response time available and once without. ResultsParticipants scored fewer points in the limited response condition compared to the unlimited response conditions. This difference was driven by a selective increase in the use of the non-paretic arm in trials where the paretic arm yielded more points. The results were not mediated by former hand dominance. ConclusionsOur results demonstrate that not using the non-paretic arm may reflect a habit response that is more readily triggered in demanding (e.g. time-limited) situations. This may explain why successful neurorehabilitation does not always result in a more functionally useful arm. Our results pave the way for targeted interventions such as habit breaking techniques to be included in clinical practise.

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bioRxiv2024

Non-invasive evidence for rhythmic interactions between the human brain, spinal cord, and muscle

Voluntary human movement relies on interactions between the spinal cord, brain, and sensory afferents. The integrative function of the spinal cord has proven particularly difficult to study directly and non-invasively in humans due to challenges in measuring spinal cord activity. Investigations of sensorimotor integration often rely on cortico-muscular coupling, which can capture interactions between the brain and muscle, but cannot reveal how the spinal cord mediates this communication. Here, we introduce a system for direct, non-invasive imaging of concurrent brain and cervical spinal cord activity in humans using optically-pumped magnetometers (OPMs). We used this system to study endogenous interactions between the brain, spinal cord, and muscle involved in sensorimotor control during simple maintained contraction. Participants (n=3) performed a hand contraction with real-time visual feedback while we recorded brain and spinal cord activity using OPMs and muscle activity using EMG. We first identify the part of the spinal cord exhibiting a peak in estimated current flow in the cervical region during contraction. We then demonstrate that rhythmic activity in the spinal cord exhibits significant coupling with both brain and muscle activity in the 5-35 Hz frequency range. These findings evidence the possibility of concurrent spatio-temporal imaging along the entire neuro-axis.

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bioRxiv2023

Combining video telemetry and wearable MEG for naturalistic imaging

Neuroimaging studies have typically relied on rigorously controlled experimental paradigms to probe cognition, in which movement is restricted, primitive, an afterthought or merely used to indicate a subjects choice. Whilst powerful, these paradigms do not often resemble how we behave in everyday life, so a new generation of ecologically valid experiments are being developed. Magnetoencephalography (MEG) measures neural activity by sensing extracranial magnetic fields. It has recently been transformed from a large, static imaging modality to a wearable method where participants can move freely. This makes wearable MEG systems a prime candidate for naturalistic experiments going forward. However, these experiments will also require novel methods to capture and integrate information about complex behaviour executed during neuroimaging, and it is not yet clear how this could be achieved. Here we use video recordings of multi-limb dance moves, processed with open-source machine learning methods, to automatically identify analysis time windows of interest in concurrent wearable MEG data. In a first step, we compare a traditional, block-designed analysis of limb movements, where the times of interest are based on stimulus presentation, to an analysis pipeline based on hidden Markov model states derived from the video telemetry. Next, we show that it is possible to identify discrete modes of neuronal activity related to specific limbs and body posture by processing the participants choreographed movement in a dancing paradigm. This demonstrates the potential of combing video telemetry with mobile neuroimaging for future studies of complex and naturalistic behaviours.

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bioRxiv2023

Ramped V1 transcranial ultrasonic stimulation modulates but does not evoke visual evoked potentials

Transcranial ultrasonic stimulation (TUS), has been shown to evoke visual evoked potential (VEP)-like potentials on EEG recordings, and also to modulate sensory evoked potentials. However, pulsed TUS is accompanied by an auditory confound, and it is possible that any observed effects were, in-part, evoked by this confound. Therefore, we used ramped TUS pulses, which are not as easily audible, to examine whether primary visual cortex (V1) TUS evokes VEP-like potentials, and modulates VEPs elicited using a checkerboard stimulus. MethodsWe tested 14 healthy participants (31 {+/-} 4.3 yrs, 4 F and 10 M). TUS was applied to the left V1 using a 270 kHz transducer (H115-2AA, Sonic Concepts). Ramped pulses (1 ms ramp, 3.25 ms total pulse duration) were repeated at 250 Hz, with a pulse train duration of 300 ms, an effective duty cycle of 50%, and Isppa without ramping of 16 W/cm2 in water. EEG was recorded from 16 channels using the g.USBamp amplifier (g.tec medical engineering GmbH). In two blocks (TUS-only), real and sham (100 each) TUS trials were repeated every 2 s. In another two blocks (TUS+checkerboard), a checkerboard stimulus was flipped every 0.5 s, and every fourth stimulus was associated with either a real or sham (100 each) TUS trial. The TUS trial started approx. 130 ms (0-5 ms jitter) before the checkerboard flip. All EEG data were analysed using Fieldtrip, and cluster-based permutation tests were used to test for differences between conditions. Results and discussionIn the TUS-only condition, in contrast to a previous study, we found no evoked potentials using ramped pulses which minimised the auditory artifact. In the TUS+checkerboard condition, we observed a modulation of the early-component of the VEP in real TUS, relative to no TUS trials. This suggests that, in line with in-vitro and animal data, there is a direct neuromodulatory effect of ultrasound, in addition to any confounding effects. Moving forward, ramping offers a relatively easy approach to minimise the auditory confound.

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bioRxiv2022

Neural activity in human eyeblink conditioning: an optically pumped magnetometer-based MEG study

There is a profound lack of electrophysiological data from the cerebellum in humans, as compared to animals, because the pervading perception is that it is difficult to record human cerebellar activity non-invasively using magnetoencephalography (MEG) or electroencephalography (EEG). We used on-scalp MEG based on optically pumped magnetometers (OP-MEG) to detect learning related cerebellar signals in a classical eyeblink conditioning paradigm. In four healthy human adults, we observed unconditioned stimulus-related evoked responses locating in the cerebellum. These evoked responses diminished during the acquisition of conditioned responses, which corresponds with previous observed changes of Purkinje cell activities in animals. We also observed evoked responses immediately before conditioned blinks in 3 out of 4 participants, which were also located in the cerebellum. We discuss the potential nature of these cerebellar evoked responses and future applications of OP-MEG to the studies of human cerebellar physiology.

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bioRxiv2022

Spatiotemporal organization of human sensorimotor beta burst activity

Beta oscillations in human sensorimotor cortex are hallmark signatures of healthy and pathological movement. In single trials, beta oscillations include bursts of intermittent, transient periods of high-power activity. These burst events have been linked to a range of sensory and motor processes, but their precise spatial, spectral, and temporal structure remains unclear. Specifically, a role for beta burst activity in information coding and communication suggests spatiotemporal patterns, or travelling wave activity, along specific anatomical gradients. We here show in human magnetoencephalography recordings that burst activity in sensorimotor cortex occurs in planar spatiotemporal wave-like patterns that dominate along two axes either parallel or perpendicular to the central sulcus. Moreover, we find that the two propagation directions are characterised by distinct anatomical and physiological features. Finally, our results suggest that sensorimotor beta bursts occurring before and after a movement share the same generator but can be distinguished by their anatomical, spectral and spatiotemporal characteristics, indicating distinct functional roles.

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bioRxiv2022

Concurrent spinal and brain imaging with optically pumped magnetometers

The spinal cord and its interactions with the brain are fundamental for movement control and somatosensation. However, brain and spinal cord electrophysiology in humans have largely been treated as distinct enterprises, in part due to the relative inaccessibility of the spinal cord. Consequently, there is a dearth of knowledge on human spinal electrophysiology, including the multiple pathologies of the central nervous system that affect the spinal cord as well as the brain. Here we exploit recent advances in the development of wearable optically pumped magnetometers (OPMs) which can be flexibly arranged to provide coverage of both the spinal cord and the brain concurrently in unconstrained environments. Our system for magnetospinoencephalography (MSEG) measures both spinal and cortical signals simultaneously by employing a custom-made spinal scanning cast. We evidence the utility of such a system by recording simultaneous spinal and cortical evoked responses to median nerve stimulation, demonstrating the novel ability for concurrent non-invasive millisecond imaging of brain and spinal cord.

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bioRxiv2022

High precision magnetoencephalography reveals increased right-inferior frontal gyrus beta power during response conflict

Flexibility of behavior and the ability to rapidly switch actions is critical for adaptive living in humans. It is well established that the right-inferior frontal gyrus (R-IFG) is recruited during outright action-stopping, relating to increased beta (12-30 Hz) power. Additionally, pre-supplementary motor area (pre-SMA) is plausibly recruited during response conflict/switching, relating to increased theta (4-8 Hz) power. It has been posited that inhibiting incorrect response tendencies is central to motor flexibility. However, it is not known if the commonly reported R-IFG beta signature of response inhibition in action-stopping is also recruited during response conflict, which would suggest overlapping networks for stopping and switching. In the current study, we analyzed high precision magnetoencephalography (hpMEG) data recorded with very high trial numbers (total n > 10,000) from 8 subjects during different levels of response conflict. We hypothesized that a R-IFG-triggered network for response inhibition is domain general and also involved in mediating response conflict. We therefore tested whether R-IFG showed increased beta power dependent on the level of response conflict. We also hypothesized that pre-SMA is an important node in response conflict processing, and tested whether pre-SMA theta power increased for response conflict trials. Using event-related spectral perturbations and linear mixed modeling, we found that both R-IFG beta and pre-SMA theta increased for response conflict trials, with the R-IFG beta increase specific to trials with strong response conflict. This result supports a more generalized role for R-IFG beta in response inhibition, beyond simple stopping behavior towards response switching. Significance StatementResponse inhibition is a core component of cognitive control. Neural mechanisms of response inhibition are typically studied using stopping paradigms. However, there is an unresolved debate regarding whether the response inhibition network is specific to stopping or generalizes to switching between tasks and overcoming conflict between competing response tendencies. Increased beta (12-30 Hz) in R-IFG has historically been interpreted as a marker of successful response inhibition in the stop-signal task. Here, we investigated the presence of this electrophysiological marker of response inhibition specifically during response conflict (switching). We found R-IFG beta power increased for trials with strong response conflict, and not for weak or no response conflict, thereby supporting a generalized role for R-IFG beta in response inhibition and switching.

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bioRxiv2021

Neural dynamics of illusory tactile pulling sensations

The sensation of directional forces and their associated sensorimotor commands are inextricably intertwined, complicating the identification of brain circuits responsible for tactile pulling sensations. One hypothesis is that, like tactile frequency discrimination, pulling sensations are generated by early sensory-frontal activity. Alternatively, they may be generated later in the somatosensory association cortex. To dissociate these accounts and uncouple the pulling sensation from unrelated but correlated sensory and motor processing, we combined high-density EEG with an oddball paradigm and asymmetric vibration, which creates an illusory sensation of the hand being directionally pulled. Oddballs that created a pulling sensation in the opposite direction to common stimuli were compared to the same oddballs in the context of neutral common stimuli (symmetric vibration) and to neutral oddballs. Brain responses to having directional pulling expectations violated by directional stimuli were therefore isolated. Contrary to the sensory-frontal account, frontal N140 brain activity was actually larger for neutral than pulling oddballs. Instead, pulling sensations were associated with amplitude and latency modulations of midline P200 and P3b potentials, and specifically, to contralateral parietal lobe activity 280ms post-stimulus. The timing of this activity suggested pulling sensations involve spatial processing, such as tactile remapping between coordinate frames. Source localization showed this activity to be centered on the postcentral sulcus, superior parietal lobule and intraparietal sulcus, suggesting that pulling sensations arise via the processing of body position, tactile orientation and peripersonal space. Our results demonstrate how tactile illusions can uniquely disambiguate parietal contributions to somatosensation by removing unrelated sensory processing. Significance statementThe neural mechanisms of tactile pulling sensations are poorly understood. Competing early sensory-frontal and later somatosensory association cortex accounts are hard to dissociate due to confounding sensory and motor signals present when forces are applied to the skin. Here, we used EEG and a novel asymmetric vibration approach to induce an illusory pulling sensation, which circumvents these issues. We found that pulling sensations were associated with parietal lobe activity 280ms post-stimulus and modulations of the P200. The timing and location of this activity suggested that pulling sensations necessitate spatial processing and supported a somatosensory association cortex account of the pulling sensation.

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bioRxiv2021

Intermanual transfer of visuomotor learning is facilitated by a cognitive strategy

Humans continuously adapt their movement to a novel environment by recalibrating their sensorimotor system. Recent evidence, however, shows that explicit planning to compensate for external changes, i.e. a cognitive strategy, can also aid performance. If such a strategy is indeed planned in external space, it should improve performance in an effector independent manner. We tested this hypothesis by examining whether promoting a cognitive strategy during a visual-force adaptation task performed in one hand can facilitate learning for the opposite hand. Participants rapidly adjusted the height of visual bar on screen to a target level by isometrically exerting force on a handle using their right hand. Visuomotor gain increased during the task and participants learned the increased gain. Visual feedback was continuously provided for one group, while for another group only the endpoint of the force trajectory was presented. The latter has been reported to promote cognitive strategy use. We found that endpoint feedback produced stronger intermanual transfer of learning and slower response times than continuous feedback. In a separate experiment, we confirmed that the aftereffect is indeed reduced when only endpoint feedback is provided, a finding that has been consistently observed when cognitive strategies are used. The results suggest that intermanual transfer can be facilitated by a cognitive strategy. This indicates that the behavioral observation of intermanual transfer can be achieved either by forming an effector-independent motor representation, or by sharing an effector-independent cognitive strategy between the hands. New and noteworthyThe causes and consequences of cognitive strategy use for motor learning are poorly understood. We tested whether a visuomotor task learned using a strategy generalizes across effectors. Visual feedback was manipulated to enhance the use of a cognitive strategy. Learning using a cognitive strategy for one hand transferred to the task performed by the un-learned hand. Our result suggests that intermanual transfer can also result from a common cognitive strategy used to control both hands.

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