Biology subjects

Taylor, J. A.

Publications and source records attributed to Taylor, J. A..

At least 19 recordsLinked to original sources

bioRxiv2026

Where you aim - not how you aim - affects implicit recalibration in visuomotor adaptation

The influence of explicit strategies on implicit recalibration during visuomotor adaptation has become a central question in motor learning. Because the two systems operate in tandem, explicit strategies could indirectly influence implicit recalibration. However, explicit strategies are not unitary: they may rely on algorithmic-based computations or memory-based retrieval of cached solutions. This raises the possibility that different strategy implementations interact with the cerebellar-based implicit recalibration system in qualitatively distinct ways, especially given that these strategies likely rely on different frontoparietal networks. Here, we tested whether the type of explicit strategy modulates implicit recalibration. Across a set of experiments, we observed subtle differences in the spatial profile of implicit generalization: the algorithmic strategy produced a broader generalization pattern than the retrieval strategy, even after controlling for intertrial decay, generalization structure, and between-target interactions. While this pattern is suggestive of greater flexibility afforded by algorithmic strategy use compared to memory-based retrieval, it could instead arise from increased variability in explicit aiming, which constitutes the input data driving implicit recalibration. Indeed, when we isolated the direct contribution of each strategy to implicit recalibration by rigorously controlling for reach variability and using error-clamp feedback to ensure uniform implicit learning conditions, we found no difference in implicit recalibration across strategies. Together, these findings suggest that while algorithmic and retrieval strategies differ in their behavioral signatures and influence the movement plan, the implicit recalibration process itself remains rigid with respect to the strategy employed.

neuroscience↗

bioRxiv2026

On the limit: Working memory capacity constrains learning of complex visuomotor mappings

Human sensorimotor adaptation critically depends on the ability to map sensory inputs onto motor outputs. While this process was once thought to rely primarily on cerebellar-dependent implicit recalibration, recent work has revealed that explicit, cognitive strategies, relying on working memory and executive function, play a substantial role. However, it remains unclear whether explicit strategies can scale to support learning of complex sensorimotor mappings. Here, we parametrically tested the capacity of explicit strategies to solve a complex visuomotor rotation task by varying the number of target-rotation pairings that participants had to acquire. In experiment 1, participants were tasked with learning four visuomotor mappings - well within working memory capacity, based on prior studies. We found that participants achieved near-perfect compensation, which was best explained by the retrieval of stored target-rotation associations, rather than by computationally demanding algorithmic strategies. In experiment 2, in an attempt to push beyond working memory capacity, participants were tasked with learning eight mappings. Unlike in experiment 1, here we found that participants failed to fully compensate for the rotations, reaching asymptotic performance of only [~]50%, despite evidence of continued strategic engagement. This performance limit was fully predicted by a parameter-free working-memory model where performance is a mixture of a fixed number of stored target-rotation associations and random guessing. These findings reveal a cognitive "bandwidth limit" on the effectiveness of strategies for sensorimotor adaptation: when task complexity exceeds this limit, adaptation plateaus, defining a fundamental constraint on how far higher-order cognition can go to support learning. Significance StatementHuman learners often compensate for perturbations in sensorimotor mappings by deploying explicit, cognitive strategies, but the scalability of these strategies for more complex tasks remains unknown. Here, we tested how performance changes as people must simultaneously learn an increasing number of distinct visuomotor rotation mappings. When presented with only a small set, participants have little difficulty - they learn by opting to forgo computationally demanding algorithmic strategies in favor of storing and retrieving target-specific solutions from working memory. However, as the number of mappings grows, this response caching strategy fails, with performance plateauing in a manner that is consistent with a capacity-limited memory bottleneck. These results highlight the critical constraint that working memory imposes on the utility of explicit strategies for sensorimotor adaptation in complex tasks.

neuroscience↗

bioRxiv2025

Implicit adaptations effect on sensorimotor and motor confidence

Sensorimotor adaptation maintains movement accuracy by counteracting perturbations or miscalibrations. It can operate explicitly, by consciously adjusting motor plans to correct errors, or implicitly, by automatically recalibrating sensorimotor mappings without altering the motor plan. While explicit adaptation is known to reduce sensorimotor confidence--the perceived likelihood of successful action--it is unclear whether implicit adaptation similarly affects confidence in sensorimotor judgments or motor awareness (knowledge of ones own limb position). To investigate this, participants made reaching movements to visual targets without seeing their hand. Cursor feedback followed an "error-clamped" trajectory: its radial position matched the hand, but its angular direction was fixed and independent of actual hand direction, a manipulation participants were told to ignore. The clamp direction varied sinusoidally over trials ({+/-}10{degrees}; 12 cycles per session). Participants reported confidence by adjusting the size of an arc centered on the target or, in another task, centered on reported reach direction; larger arcs indicated lower confidence. Points were awarded when the arc encompassed the true reach direction, with fewer points for larger arcs, encouraging accurate and meaningful confidence reports. Fourier analysis of reach and report time series revealed a strong 12-cycle component in both, demonstrating robust implicit adaptation and corresponding changes in motor awareness. These findings indicate that although implicit adaptation operates unconsciously, the resulting mismatch between motor plans and proprioceptive signals can bias judgments of reach outcomes. However, confidence judgments were not consistently affected, suggesting that sensorimotor confidence and confidence in proprioceptive awareness may rely on partially distinct mechanisms. New & NoteworthyThis work is among the first to look at how implicit adaptation influences meta-judgments regarding motor execution and internal states. It identifies a dissociation between sensorimotor confidence and motor-awareness confidence.

neuroscience↗

bioRxiv2025

Cortical neuroprostheses improve auditory coding and perception compared to cochlear implants

Cochlear implants have transformed the treatment of hearing loss by enabling auditory perception through direct electrical stimulation of the auditory nerve. However, their effectiveness can be limited in noisy environments, for fine frequency resolution, and in patients lacking an intact auditory nerve. The auditory cortex offers a promising alternative target for neuroprosthetic stimulation, but it remains unclear whether direct cortical input can evoke percepts with the complexity and structure of natural sounds. Here we show that surface cortical implants in mice support robust and flexible auditory behaviour, surpassing cochlear implants in tasks requiring fine spectral, temporal, and noise-resistant discrimination. We also show that animals generalize seamlessly between cortical and acoustic stimuli without additional training, indicating that cortical stimulation can generate interpretable, sound-like percepts. Electrophysiological recordings revealed that cortical stimulation drives spatially and temporally structured neural activity in auditory cortex, resembling responses to natural sound. These findings establish that the auditory cortex can interpret spatially and temporally patterned electrical input in a behavioural relevant way. By linking neuroprosthetic stimulation to naturalistic neural representations and behavioural generalization, this work provides a mechanistic and functional foundation for cortical auditory neuroprostheses and points toward new strategies for restoring hearing through direct brain stimulation.

neuroscience↗

bioRxiv2025

Revisiting the explicit-implicit additivity assumption in visuomotor adaptation

Explicit aiming strategies have been shown to play an important role in visuomotor adaptation - enabling rapid improvements in performance and affording flexibility - but their interaction and downstream consequences on implicit recalibration processes remain hotly debated. While early work assumed these processes combined additively, recent studies have challenged this view. However, these studies may have overlooked subtle spatial and temporal dynamics, which could influence how explicit aiming and implicit recalibration interact. Recent research shows that implicit recalibration anchors to where a person aims their movements, with aiming strategies directly shaping their spatial development. Moreover, implicit recalibration operates across multiple timescales, with both temporally volatile and persistent components. To examine whether these factors mask the true relationship between explicit strategies and implicit recalibration, we conducted a visuomotor rotation task while carefully accounting for the interplay of spatial and temporal dynamics. After controlling for spatial dynamics (plan-based generalization) and temporal dynamics (forgetting), we found a strong relationship between explicit strategies and implicit recalibration. Despite finding this strong relationship, it appears to be sub-additive, which may result from simple methodological imprecision, the operation of additional but unobserved processes, or more complex nonlinear interactions between processes.

neuroscience↗

bioRxiv2025

Asymmetric centromere and gene locus positioning in Drosophila neural stem cells

Chromatin organization is important for cell division, epigenetic memory, and gene regulation. It is often reflected in the non-random positioning of centromeres, but the underlying mechanisms and functions remain largely unknown. Here, we demonstrate that asymmetrically dividing Drosophila neural stem cells cluster centromeres near the nuclear envelope, adjacent to the apical centrosome. This asymmetric centromere positioning is regulated through microtubules, originating from the apical centrosome that connect to apical nuclear pore complexes. The minus-end directed motor protein Dynein, its binding partner Mushroom body defect, and Lamin are also required. Asymmetric centromere positioning persists throughout interphase in neural stem cells but is lost in more differentiated progeny. We also reveal that the genes hunchback (hb) and pendulin (pen) occupy specific nuclear regions, correlating with polarized centromere localization. We propose that fly neural stem cells translate their inherent polarity into stereotypical chromatin organization, potentially influencing cell fate decisions and stem cell behavior.

cell biology↗

bioRxiv2025

Distinct Implicit Contributions to Action Selection and Action Execution in Sensorimotor Adaptation

The sensorimotor system is continuously adjusted to minimize error. Current theories assume that this adaptation process entails the operation of multiple learning systems, with a key division between implicit and explicit components. Recent studies have revealed several inconsistencies regarding the characteristics and constraints of the implicit system, suggesting that the current framework is incomplete. Here, we propose that these conflicting findings can be understood by recognizing that there are multiple implicit subcomponents, distinguished by their distinct computational goals. One well-studied component is implicit recalibration, a process critical for action execution which uses sensory-prediction errors to automatically refine the sensorimotor map. Here we describe a second, novel component, implicit aiming, a process which contributes to action selection to achieve the specific goals. Through a series of studies, we find compelling evidence that those two implicit processes show a clear separation in their temporal stabilities and contextual modulations. These distinct properties correspond to different computational frameworks attributing learning dynamics to either contextual inference or cancellation of competing neural populations, respectively. Together, these findings suggest an alternative framework for sensorimotor adaptation based on the computational goals of the system rather than phenomenology.

neuroscience↗

bioRxiv2025

Targeting PI3K Signaling for Broad Inhibition of β-Coronavirus Infection

The phosphatidylinositol 3-kinase (PI3K) signaling pathway plays a central role in regulating key cellular processes such as survival, metabolism, and immune responses. Aberrant activation of this pathway is associated with tumorigenesis, and several PI3K inhibitors have been developed as anticancer agents. Emerging evidence suggests that viruses, including {beta}-coronaviruses, have evolved mechanisms to exploit host PI3K signaling for their replication and immune evasion. In this study, we evaluated the antiviral efficacy of a panel of PI3K inhibitors against {beta}-coronaviruses, including mouse hepatitis virus (MHV), human OC43 (HuCoV-OC43) and four major SARS-CoV-2 variants using both cell line and organoid models. Our findings reveal that these compounds exhibit low micromolar potency in inhibiting viral replication. Notably, the inhibitor C20 (PWT33597) demonstrated broad-spectrum activity against multiple {beta}-coronaviruses, including SARS-CoV-2, MHV, and HuCoV-OC43, in conventional cell lines as well as in air-liquid interface (ALI)-cultured, differentiated primary human nasal and bronchial epithelial cells. Given that cytokine storm is a major contributor to SARS-CoV-2-related multiorgan failure and mortality, we further explored the impact of PI3K inhibition on host inflammatory responses. We found that MHV infection markedly increased cytokine expression in 17CL-1 fibroblasts and RAW264.7 macrophages. Interestingly, treatment with C20 further amplified cytokine production in this context, suggesting complex immunomodulatory effects that warrant further investigation. Together, our findings support the therapeutic potential of repurposing PI3K inhibitors as broad-spectrum antivirals. These compounds not only suppress viral replication but may also influence host immune responses, providing a promising avenue for intervention against current and emerging coronavirus threats.

microbiology↗

bioRxiv2024

Mycobacterium tuberculosis CrgA Forms a Dimeric Structure with Its Transmembrane Domain Sandwiched between Cytoplasmic and Periplasmic β-Sheets, Enabling Multiple Interactions with Other Divisome Proteins

CrgA is a key transmembrane (TM) protein in the cell division process of Mycobacterium tuberculosis (Mtb), the pathogen responsible for tuberculosis. While many of the Mtb divisome proteins have been identified, their structures and interactions remain largely unknown. Previous studies of CrgA using oriented-sample solid-state NMR have defined the tilt and rotation of the TM helices, but the cytoplasmic and periplasmic domains and even the oligomeric state were uncharacterized. Here, combining oriented-sample and magic-angle spinning solid-state NMR spectra, we solved the full-length structure of CrgA. The structure features a dimer with a TM domain sandwiched between a cytoplasmic {beta}-sheet and a periplasmic {beta}-sheet. The {beta}-sheets stabilize dimerization, which in turn increases CrgAs ability to participate in multiple protein interactions. Within the membrane, CrgA binds FtsQ, CwsA, PbpA, FtsI, and MmPL3 via its TM helices; in the cytoplasm, Lys23 and Lys25 project outward from the {beta}-sheet to interact with acidic residues of FtsQ and FtsZ. The structural determination of CrgA thus provides significant insights into its roles in recruiting other divisome proteins and stabilizing their complexes for Mtb cell wall synthesis and polar growth.

biophysics↗

bioRxiv2024

Sex-dependent effects of CYP2E1 on the kidney and the protective potential of 4MP against cisplatin-induced nephrotoxicity

Cisplatin is an effective chemotherapeutic drug for the treatment of bladder cancer, though cisplatin-induced nephrotoxicity (CIN) occurs in approximately 20-30% of patients, limiting its clinical use. Evidence has shown that cytochrome P450 2E1 (CYP2E1), a drug metabolism enzyme expressed in proximal tubules, mediates the production of reactive oxygen species (ROS) during cisplatin-induced injury. Previously, we showed that the repurposed drug 4-methylpyrazole (4MP; fomepizole) blocks CYP2E1 activity and prevents acetaminophen-induced liver injury. Here, we investigated the potential protective effects of 4MP against CIN. Male and female C57BL/6J mice were treated with a single 20 mg/kg dose of cisplatin for 3 days (acute) or 9 mg/kg/week for 4 weeks (repeated dosing regimen) with or without 50 mg/kg 4MP as a co-treatment. Our findings revealed that acute treatment with cisplatin induced severe histological tubular damage and elevated plasma BUN and creatinine levels in male mice, but not in female mice. This difference correlated with higher basal CYP2E1 expression in the kidneys of male mice compared to female mice. We also found that cisplatin increased renal CYP2E1 activity and that inhibition of CYP2E1 with 4MP significantly reduced cisplatin induced cell death in male mice and primary normal human kidney cells. By contrast, human bladder cancer cells do not express CYP2E1, and treatment with 4MP did not interfere with cisplatins anti-cancer effects in human bladder cancer HTB9 cells. This study highlights the critical role of CYP2E1 in CIN and suggests that its inhibition with 4MP in the kidney is a potential prophylactic therapeutic option to prevent CIN in bladder cancer patients without affecting its anti-neoplastic effect. Impact StatementThis study demonstrates that cytochrome P450 2E1 (CYP2E1) is a critical mechanistic target in the prevention of cisplatin-induced nephrotoxicity (CIN). It also indicates that CYP2E1 plays an important role in mediating sex-specific differences in CIN. Finally, this study reveals that targeting CYP2E1 with 4methylpyrazole offers a promising prophylactic approach to reducing CIN in clinical settings while preserving the anti-cancer efficacy of cisplatin.

pharmacology and toxicology↗

bioRxiv2024

Learning to Move and Plan like the Knight: Sequential Decision Making with a Novel Motor Mapping

Many skills that humans acquire throughout their lives, such as playing video games or sports, require substantial motor learning and multi-step planning. While both processes are typically studied separately, they are likely to interact during the acquisition of complex motor skills. In this work, we studied this interaction by assessing human performance in a sequential decision-making task that requires the learning of a non-trivial motor mapping. Participants were tasked to move a cursor from start to target locations in a grid world, using a standard keyboard. Notably, the specific keys were arbitrarily mapped to a movement rule resembling the Knight chess piece. In Experiment 1, we showed the learning of this mapping in the absence of planning, led to significant improvements in the task when presented with sequential decisions at a later stage. Computational modeling analysis revealed that such improvements resulted from an increased learning rate about the state transitions of the motor mapping, which also resulted in more flexible planning from trial to trial (less perseveration or habitual responses). In Experiment 2, we showed that incorporating mapping learning into the planning process, allows us to capture (1) differential task improvements for distinct planning horizons and (2) overall lower performance for longer horizons. Additionally, model analysis suggested that participants may limit their search to three steps ahead. We hypothesize that this limitation in planning horizon arises from capacity constraints in working memory, and may be the reason complex skills are often broken down into individual subroutines or components during learning.

animal behavior and cognition↗

bioRxiv2024

Working memory constraints for visuomotor retrieval strategies

Recent work has shown the fundamental role that cognitive strategies play in visuomotor adaptation. While algorithmic strategies, such as mental rotation, are flexible and generalizable, they are computationally demanding. To avoid this computational cost, people can instead rely on memory retrieval of previously successful visuomotor solutions. However, such a strategy is likely subject to strict stimulus-response associations and rely heavily on working memory. In a series of five experiments, we sought to estimate the constraints in terms of capacity and precision of working memory retrieval for visuomotor adaptation. This was accomplished by leveraging different variations of visuomotor item-recognition and visuomotor rotation recall tasks where we associated unique rotations with specific targets in the workspace and manipulated the set size (i.e., number of rotation-target associations). Notably, from Experiment 1 to 4, we found key signatures of working memory retrieval and not mental rotation. In particular, participants were less accurate and slower for larger set sizes and less recent items. Using a Bayesian-latent mixture model, we found that such decrease in performance is the result of both an increase in guessing behavior and of less precise samples from memory. In addition we estimated that participants working memory capacity was limited to 2-5 items, after which guessing increasingly dominated performance. Finally, in Experiment 5, we showed how the constraints observed across Experiments 1 to 4 can be overcome when relying on long-term memory retrieval. Our results point to the opportunity of studying other sources of memories where visuomotor solutions can be stored (e.g., episodic memories) to achieve successful adaptation.

animal behavior and cognition↗

bioRxiv2023

Learning generalizable visuomotor mappings for de novo skills

A fundamental feature of the human brain is its capacity to learn novel motor skills. This capacity requires the formation of vastly different visuomotor mappings. In this work, we ask how these associations are formed de novo, hypothesizing that under specific training regimes generalizable mappings are more readily formed, while in others, local state-actions associations are favored. To test this, we studied learning in a simple navigation task where participants attempted to move a cursor between various start-target locations by pressing three keyboard keys. Importantly, the mapping between the keys and the direction of cursor movement was unknown to the participants. Experiments 1 and 2 show that participants who were trained to move between multiple start-target pairs had significantly greater generalization than participants trained to move between a single pair. Whereas Experiment 1 found significant generalization when start-targets were distal, Experiment 2 found similar generalization for proximal targets, which suggests that generalization differences are due to knowledge of the visuomotor mapping itself and not simply due to planning. To gain insight into the potential computational mechanisms underlying this capacity, we explored how a visuomotor mapping could be formed through a set of models that afforded construction of a generalizable mappings (model-based), local state-action associations (model-free), or a hybrid of both. Our modeling work suggested that without continued variability between start-target pairs during training, model-based processes eventually gave way to model-free processes. In Experiment 3, we sought to further test this shift in learning processes by exposing participants to initially high variability before settling into a condition of no variability over a long-period of training. We found that generalization performance remained intact after a prolonged period of no variability suggesting that the formation of visuomotor mappings might occur at an early stage of learning. Finally, in Experiment 4 we show that adding stochasticity in the mapping can also promote model-based learning of a visuomotor mapping, suggesting that the learning may unfold implicitly. Overall, these studies shed light on how humans could acquire visuomotor mappings in their lives through exposure to variability in their feedback.

animal behavior and cognition↗

bioRxiv2023

On the money and right on target: How robust are reward and task success effects on implicit motor adaptation?

While implicit motor adaptation is driven by sensory-prediction errors (SPEs), recent work has shown that task success modulates this process. Task success has typically been defined as hitting a target, which signifies the goal of the movement. Visuomotor adaptation tasks are uniquely situated to experimentally manipulate task success independently from SPE by changing the target size or the location of the target. These two, distinct manipulations may influence implicit motor adaptation in different ways, so, over four experiments, we sought to probe the efficacy of each manipulation. We found that changes in target size which caused the target to fully envelop the cursor only affected implicit adaptation for a narrow range of SPE sizes, while jumping the target to overlap with the cursor more reliably and robustly affected implicit adaptation. Taken together, our data indicate that, while task success exerts a small effect on implicit adaptation, these effects are susceptible to methodological variations. Future investigations of the effect of task success on implicit adaptation could benefit from employing target jump manipulations instead of target size manipulations.

neuroscience↗

bioRxiv2022

LRRK2 Phosphorylates Neuronal Elav RNA-Binding Proteins to RegulatePhenotypes Relevant to Parkinson's Disease

Parkinsons disease (PD) is characterized by accumulation of -synuclein and the loss of dopaminergic neurons. Mutations which cause an increase in the kinase activity of Leucine-Rich-Repeat Kinase-2 (LRRK2) are a major inherited cause of PD. Research continues to determine which targets LRRK2 phosphorylates to cause disease. Polymorphisms in the locus of ELAVL4, an RNA-binding protein are a risk-factor for Parkinsons disease and an ELAV family member was identified in Drosophila as required for pathology instigated by human mutant LRRK2. We discovered that three neuronal ELAVs including ELAVL4 (also known as HuD) are phosphorylated by LRRK2. This controls binding of neuronal ELAVs to mRNA and their post- transcriptional regulation of mRNA abundance and splicing in neuronal cell lines and the mouse midbrain. LRRK2 G2019S functionally inhibits neuronal ELAVs effects on mRNA abundance, while enhancing their effects on mRNA splicing. The combination of LRRK2 G2019S and ELAVL4-/- causes accumulation of LRRK2 and -synuclein, loss of dopaminergic neurons and motor deficits. Targets of neuronal ELAVs are also selectively misregulated in cells and tissues of PD patients. Together, this suggests that misregulation of neuronal ELAVs, triggered by LRRK2 mutations may contribute to the characteristic pathology of Parkinsons disease. Brief SummaryLRRK2, a kinase linked to Parkinsons disease, phosphorylates the neuronal ELAV RNA-binding proteins to aggravate key hallmarks of Parkinsons disease including accumulation of -synuclein and motor deficits in mice.

cell biology↗

bioRxiv2021

A Single Molecule Investigation of I-Motif: Stability, Folding Kinetics, and Potential as an In-situ pH Sensor

We present a collection of single molecule work on the i-motif structure formed by the human telomeric sequence. Even though it was largely ignored in earlier years of its discovery due to its modest stability and requirement for physiologically low pH levels (pH<6.5), the i-motif has been attracting more attention recently as both a physiologically relevant structure and as a potent pH sensor. In this manuscript, we establish single molecule Forster resonance energy transfer (smFRET) as a tool to study the i-motif over a broad pH and ionic conditions. We demonstrate pH and salt dependence of i-motif formation under steady state conditions and illustrate the kinetics of i-motif folding in real time at the single molecule level. We also show the prominence of intermediate folding states and reversible folding/unfolding transitions. We present an example of using the i-motif as an in-situ pH sensor and use this sensor establish the time scale for the pH drop in a commonly used oxygen scavenging system.

biophysics↗

bioRxiv2021

Direct and indirect cues can enable dual-adaptation, but through different learning processes

Switching between motor tasks requires accurate adjustments for changes in dynamics (grasping a cup) or sensorimotor transformations (moving a computer mouse). Dual-adaptation studies have investigated how learning of context-dependent dynamics or transformations is enabled by sensory cues. However, certain cues, such as color, have shown mixed results. We propose that these mixed results may arise from two major classes of cues: "direct" cues, which are part of the dynamic state and "indirect" cues, which are not. We hypothesized that explicit strategies would primarily account for adaptation for an indirect color cue but would be limited to simple tasks while a direct visual separation cue would allow implicit adaptation regardless of task complexity. To test this idea, we investigated the relative contribution of implicit and explicit learning in relation to contextual cue type (colored or visually shifted workspace) and task complexity (one or eight targets) in a dual-adaptation task. We found that the visual workspace location cue enabled adaptation across conditions primarily through implicit adaptation. In contrast, we found that the color cue was largely ineffective for dual-adaptation, except in a small subset of participants who appeared to use explicit strategies. Our study suggests that the previously inconclusive role of color cues in dual-adaptation may be explained by differential contribution of explicit strategies across conditions. New & NoteworthyWe present evidence that learning of context-dependent dynamics proceeds via different processes depending on the type of sensory cue used to signal the context. Visual workspace location enabled learning different dynamics implicitly, presumably because it directly enters the dynamic state estimate. In contrast, a color cue was only successful where learners were apparently able to leverage explicit strategies to account for changed dynamics. This suggests a unification for the previously inconclusive role of color cues.

neuroscience↗

bioRxiv2021

Taking aim at the perceptual side of motor learning: Exploring how explicit and implicit learning encode perceptual error information through depth vision

Motor learning in visuomotor adaptation tasks results from both explicit and implicit processes, each responding differently to an error signal. While the motor output side of these processes is extensively studied, their visual input side is relatively unknown. We investigated if and how depth perception affects the computation of error information by explicit and implicit motor learning. Two groups of participants threw virtual darts at a virtual dartboard while receiving perturbed endpoint feedback. The Delayed group was allowed to re-aim and their feedback was delayed to emphasize explicit learning, while the Clamped group received clamped cursor feedback which they were told to ignore, and continued to aim straight at the target to emphasize implicit adaptation. Both groups played this game in a highly detailed virtual environment (Depth condition) and in an empty environment (No-Depth condition). The Delayed group showed an increase in error sensitivity under Depth relative to No-Depth conditions. In contrast, the Clamped group adapted to the same degree under both conditions. The movement kinematics of the Delayed participants also changed under the Depth condition, consistent with the target appearing more distant, unlike the Clamped group. A comparison of the Delayed behavioral data with a perceptual task from the same individuals showed that the effect of the Depth condition on the re-aiming direction was consistent with an increase in the scaling of the error distance and size. These findings suggest that explicit and implicit learning processes may rely on different sources of perceptual information. New & NoteworthyWe leveraged a classic sensorimotor adaptation task to perform a first systematic assessment of the role of perceptual cues in the estimation of an error signal in the 3D space during motor learning. We crossed two conditions presenting different amounts of depth information, with two manipulations emphasizing explicit and implicit learning processes. Explicit learning responded to the visual conditions, consistent with perceptual reports, while implicit learning appeared to be independent of them.

neuroscience↗