Journal of Experimental Psychology: Human Perception and Performance

Visual working memory allows for the brief maintenance of information to serve behavioral goals. It has been shown that when the specific action required to serve a future goal is predictable, people can flexibly change a visual memory representation to incorporate an action-based one, demonstrating the goal-oriented nature of visual working memory. Can such flexibility also be observed within the visual domain, between color and space? In this eye-tracking study, participants remembered either a centrally presented color or a spatial position around fixation. Critically, when remembering a color the response wheel was either randomly rotated, or shown at a fixed rotation, on every trial. When fixed, every target color could be associated with a predictable position on the wheel during response. Do people incorporate this added spatial information in their behavior? Participants utilized color-space associations when remembering color: Response initiation happened faster when the color wheel was fixed compared to random, irrespective of whether an action could be planned or not. Next, we showed that gaze was biased towards the position of the spatial memory target during the delay, extending previous work on gaze biases. Importantly, also when remembering a color, gaze was biased towards the anticipated position of that color on the response wheel when it was fixed. Together, our results show a behavioral benefit of added spatial information for color memory, and systematic changes in gaze that reflect flexible utilization of space.

How does the structure of events influence the when and the where of experience in comparison to the what? We developed a novel virtual reality (VR) environment to understand how the quantity of information within nested structures influence participants memory for events. Participants moved through a series of virtual rooms (events) where images (items) appeared in randomised locations on a 3 by 3 grid located on a wall. Participants were asked to remember the what (old/new), when (timeline location), and where (grid location), of the images they experienced. Two types of nested events were tested (6 rooms, each containing 4 images; 3 rooms, each containing 8 images) without a difference in the number of seconds of presentation. We found a strong temporal compression effect at nested levels in which participants remembered early items and events happening later, and later items and events happening earlier, than the original experience. Crucially, presenting four-item events resulted in a greater compression rate than eight-item events. We also found greater temporal distances between pairs of items occurring within eight-item events than pairs of items which occurred on either side of a boundary. Memory for when depends on the compression of information within events.

When individuals view the same visual input, they often differ in their aesthetic appeal judgments, yet why people differ remains largely unclear. Here, we tested whether individual differences in aesthetic experience are linked to differences in visual exploration. In two experiments, participants watched the documentary "Home" while their eye movements were recorded. In Experiment 1, participants continuously rated aesthetic experience throughout the movie, whereas in Experiment 2, they watched the first half without a task and rated aesthetic experience only during the second half. Inter-individual similarity in gaze patterns, assessed using fixation heatmaps across time, predicted similarity in aesthetic appeal judgments in both experiments. Notably, in Experiment 2, gaze similarity during free viewing in the first half of the movie predicted similarity in aesthetic ratings during the second half, indicating that incidental eye movement patterns predict aesthetic experiences. Together, these results show that shared gaze patterns are linked to shared aesthetic experiences under naturalistic, dynamic viewing conditions.

Visual perception of symbolic numerals is essential for everyday tasks; however, the neural and perceptual mechanisms underlying this ability remain unclear. Partially occluded digital numerals can elicit bistable perception, and adaptation to symbolic numerals alters the perception of these ambiguous stimuli. We aimed to examine how symbolic numeral adaptation is related to hierarchical visual processing by testing its interocular and interhemifield transfer. Experiment 1 tested interocular transfer by presenting the test stimulus to either the same or opposite eye as the adaptation stimulus. Experiment 2 assessed interhemifield transfer by presenting the test stimulus to either the same or opposite hemifield as the adaptation stimulus. Experiment 3 examined the interhemifield transfer of adaptation confined to the upper parts of digital numerals. Our results showed that adaptation to digital numerals induced shifted perceptual interpretations that transferred across eyes. In addition, we found that adaptation to digital numerals induced a relatively small but statistically significant interhemifield transfer. In contrast, adaptation restricted to the upper parts of digital numerals showed no significant interhemifield transfer. These findings suggest that the perceptual interpretation of symbolic numerals involves visual processing stages that integrate information across the eyes and hemifields.

Plant Awareness Disparity (PAD) refers to the inability of humans to notice plants and recognize their importance. Among the various factors (e.g., cultural) contributing to PAD, the less prominent visual cues of plants (e.g., color) might be one of the main features making them less noticeable to human perception. Here, we investigated whether PAD affects basic numerosity perception, which represents a fundamental cognitive ability that allows individuals to interpret and interact with their surroundings. Across three experiments, we compared how participants perceive the numerosity of plants (specifically trees), animals, and minerals. Participants completed two tasks: an estimation task, in which they reported the exact number of items in a single set and a comparison task, which required them to discriminate numerosity between two sets of items. In Experiment 1, both tasks employed colored images. We hypothesized that participants would underestimate the number of plant items in comparison to animals and minerals, given that plant stimuli typically attract less attention. In Experiment 2, black and white images were used to test whether the green color of plants contributes to PAD. In Experiment 3, all items were rotated of 180{degrees} to disrupt semantic recognition and assess whether PAD arises from higher-level cognitive processes. Results revealed a consistent underestimation of plants in Experiment 1 and 2, but this effect diminished in Experiment 3. The reduction of this effect suggests that semantic recognition processes may contribute to PAD. These results highlight how cognitive biases toward plants can influence basic perceptual judgments essential for everyday functioning.

Choice overload occurs when an ever-growing number of options impairs decision quality, because evaluating options taxes cognitive resources. We investigated whether reducing cognitive demand could mitigate overload by encouraging greater cognitive effort to achieve optimal choice. We conducted two experiments manipulating cognitive demand in complementary ways: Experiment 1 reduced demand by presenting high-attractiveness sets, and Experiment 2 did so by providing a shortlist tool. In both experiments, participants chose from sets of 6-24 options while their eye-gaze and electroencephalographic (EEG) data were recorded. We found that reducing demand made decisions faster, but did not improve choice performance as set-size increased. Under low-demand conditions, eye-gaze measures revealed narrower search and EEG measures showed reduced working memory engagement per option, together indicating less searching and processing efforts. These results suggest that even with reduced cognitive demand, people coast through easier decisions, conserving effort and leaving the choice overload effect largely intact.

When successive stimuli occur close enough together in time, their perception can be impaired. Such impairments indicate temporal competition between successive stimuli for representational resources. Voluntary temporal attention can bias processing resources in favor of a behaviorally relevant moment, improving perception at the attended time at the expense of impairments at unattended times. However it is unclear whether these perceptual tradeoffs across time arise because voluntary temporal attention selects among actively competing stimulus representations, such as within visual working memory, or if instead, temporal attention facilitates stimulus processing prior to a competitive stage. Here we used a temporal cueing task with up to two targets in succession to test whether and how the effects of temporal attention depend on temporal competition. We found that voluntary temporal attention improved performance even in the absence of temporal competition, when only one stimulus appeared during the trial. Moreover, the magnitude of attentional enhancement was comparable with and without competition. These results suggest that voluntary temporal attention enhances perception by facilitating processing prior to a competitive stage, rather than by resolving conflicts between actively competing stimulus representations. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=126 SRC="FIGDIR/small/705419v2_ufig1.gif" ALT="Figure 1"> View larger version (20K): org.highwire.dtl.DTLVardef@1f1f8dforg.highwire.dtl.DTLVardef@10a33f1org.highwire.dtl.DTLVardef@d81cfborg.highwire.dtl.DTLVardef@56a432_HPS_FORMAT_FIGEXP M_FIG C_FIG

Older adults rely increasingly on prior knowledge to make sense of their deteriorating representation of the visual world, but how this shapes scene perception and spatial reorientation remains unclear. To address this issue, 28 young and 25 older adults viewed artificially generated rooms either before or after learning the position of a goal hidden in an adjacent room. We manipulated both the number and the eccentricity of navigational affordances (i.e., open doors) to investigate the interaction between bottom-up scene features and top-down spatial knowledge. Consistent with previous findings, younger adults showed decreased performance as the number of open doors increased, but only after learning the goals position, indicating a top-down interaction with the automatic processing of affordances. Door eccentricity did not affect this interaction, suggesting our findings were not due to a distractor effect. In older adults, this interaction between prior spatial information and navigational affordances was markedly amplified: reaction times increased at twice the rate observed in younger adults. These findings show that prior spatial knowledge interacts with the automatic extraction of navigational affordances, and that this influence is markedly amplified with age. While prior knowledge helps stabilize perception when sensory processing becomes less reliable, it can also increase the processing time for complex scenes, particularly when multiple action possibilities are present. By revealing how aging shifts the balance between top-down and bottom-up mechanisms, these results refine models of age-related spatial navigation decline and highlight a trade-off whereby increased reliance on prior knowledge supports perception but can also slow interaction with complex environments.

When one object approaches another object which, upon touching, moves in the same direction, humans report a vivid impression of one launching the other. Visual adaptation can alter this perception of causality: observers less often report seeing a launch after viewing a stream of launch events. In three experiments, we further characterised how visual adaptation influences the perception of causality by determining the spatial specificity of adaptation and timecourse of recovery from adaptation. In Experiment 1, observers saw ambiguous test events (i.e., the overlap between the two objects varied over trials) at three different horizontal eccentricities. Adaptation was strongest when adaptor and test event were presented at the same eccentricity, and absent when the two were separated by just three degrees of visual angle. Moreover, the perception of causality gradually recovered from adaptation, but remained incomplete. In Experiment 2, both long and short adaptation sequences were highly effective in driving adaptation, and showed no difference in the recovery timecourse, which was complete following more experimental blocks. In Experiment 3, a break without any task-relevant visual input also led to a recovery over the same timespan, but this time, the recovery was instantaneous and incomplete. Altogether, our results provide evidence for highly spatially specific computations, instananeously responding to the onset of adaptation and then gradually recovering from the adaptation over a short time window.

Each individual person looks at natural scenes in their own unique way, resulting in a distinct perceptual experience of the world. However, little is known about why such differences in gaze emerge. Here, we test the hypothesis that idiosyncrasies in gaze behavior are predicted by inter-subject variations in internal models--expectations about how scenes typically look. In two experiments, we first characterized participants personal internal models by asking them to draw typical bathroom and kitchen scenes. Individual differences in these drawings were quantified using an objective deep learning pipeline and, in turn, related to individual differences in gaze behavior. In Experiment 1, where participants freely viewed a set of kitchen and bathroom photographs, inter-subject similarities in internal models did not predict inter-subject similarities in gaze. In Experiment 2, we encouraged strategic exploration through gaze-contingent viewing and a memory task. Here, inter-subject similarities in internal models predicted similarities in fixation frequency and the sequence in which different object categories were inspected. These findings suggest that the influence of internal models on visual exploration is stronger under increased sensory uncertainty and when expectation-guided sampling of the environment is encouraged. Together, our results provide new insights into how individual expectations shape gaze behavior and help explain why people differ in how they explore the visual world.

Color is a prominent feature of visual experience, yet humans can recognize objects easily and accurately from grayscale images. We examined whether color becomes more useful when spatial information is degraded due to blurring. Participants viewed naturalistic scenes in color or grayscale, and reported whether a named target object was present across a range of blur levels that simulated optical defocus from 0-8 diopters. With unblurred images, performance did not differ between color and grayscale conditions, but as blur increased, recognition accuracy declined. Color provided a modest but reliable advantage at higher levels of blur, suggesting that color becomes increasingly useful when optical quality is degraded. We hypothesize that the evolutionary shift towards trichromacy may have been partially driven by the need to compensate for optical degradation due to aging and/or accumulated light exposure.

Stored memories are useless unless they are available for retrieval. Thus, investigating different ways to modulate retrieval is crucial. Novelty has been extensively studied as a modulator of memory. In this study, we investigated whether exposure to a novel event, an innovative neuroscience lesson, can enhance memory retrieval and divergent thinking in high school students. Across three experiments, we assessed the timing and mechanisms underlying these effects. In experiment 1, we found that memory retrieval was enhanced when the novel lesson occurred immediately before a memory test, but not when it was presented one hour earlier. In experiment 2, we found that the same immediate novelty exposure improved divergent thinking performance. Finally, in experiment 3, we explored potential shared mechanisms using a competition protocol and revealed that novelty improved divergent thinking regardless of its timing relative to memory retrieval. However, memory retrieval benefited only when tested immediately before the divergent thinking task. These results suggest that novelty boosts both memory retrieval and divergent thinking, but through partially distinct mechanisms. Our findings demonstrate that a simple, real-world classroom intervention can effectively enhance key cognitive functions in students. Significance StatementStored memories are only valuable if they can be retrieved, and memory retrieval plays a key role in creative thinking. Here, we tested whether a simple, novel event, a neuroscience lesson, could enhance memory retrieval and creative thinking in a real-world classroom setting. We found that novelty improved both memory retrieval and divergent thinking, an aspect of creative thinking, when presented immediately before the task. Finally, we revealed a non-reciprocal competition effect between memory retrieval and divergent thinking. These findings highlight a practical, low-cost intervention to boost key cognitive functions in students, demonstrating that brief, well-timed novel experiences can support both learning and creative thinking in educational environments.

Humans can predict an objects motion better if its movements are consistent with gravity. Here we investigate whether this may be due to an internalized strong Earth gravity prior or to vestibular cues reporting instantaneous information about gravity. These two directions can be separated using virtual reality by providing strong visual cues to the direction of up which may or may not be aligned with true gravity. Participants were presented with a ball travelling on a parabola path simulated with either downward acceleration created by simulated Earths gravity (1g) or inverted gravity (-1g) resulting in the ball curving upwards. In both types of trial, the ball disappeared at between 57.5% and 75% of its full trajectory - after it had started its descent in the case of 1g or ascent in the case of -1g. Participants pressed a mouse button when they judged the ball to have got back to the height at which it was launched. Participants were either standing or supine. There were no differences in the estimated time to reach the indicated level between the 1g and -1g simulations, however, we found an overestimation of the perceived time for the ball to reach target height when observers were lying supine compared to when they were standing upright independent of the gravity condition simulated. A control experiment confirmed that this was not due to a general slowing of reaction times while lying supine versus while upright. To explore whether these observations might reflect posture-related changes in vestibular activity, participants completed the task under both simulated gravity conditions while seated upright in the presence of disruptive galvanic vestibular stimulation (dGVS) or during sham stimulation. As when lying supine, the perceived time for the ball to reach the target height was significantly longer in the presence of dGVS compared to during sham stimulation. Overall, participants were no better at anticipating 1g motion compared to -1g motion, but we provide compelling evidence that the state of vestibular signalling can impact the prediction of object motion.

Habits in humans are commonly studied through outcome devaluation paradigms, but most existing tasks fail to capture the robustness of habitual behavior seen in animal models. I introduce two novel behavioral tasks designed to overcome these limitations. In the first task, ("shooting aliens task", n = 45), I simplified an existing instrumental learning task and implemented a novel intra-block reversal method in which stimulus positions changed unexpectedly within blocks while maintaining the same stimulus-action mappings. Participants also completed a classical devaluation phase with explicit reward changes. In the second task ("hands-attack task", n = 44), which relied on real-life avoidance behavior, devaluation was achieved by reversing reward contingencies and allowing participants to inhibit the dominant avoidance response in favor of a more effortful counterattack. Across both tasks, overtrained conditions led to more errors and longer response times after devaluation, confirming increased insensitivity to outcome change. Intra-block reversals in the shooting aliens task produced stronger habitual signatures than standard whole-block devaluation, revealing a greater cost of overriding automatic responses. In the hands-attack task, even without prior training, participants showed clear markers of habitual behavior, suggesting that real-world action patterns can replicate key features of laboratory habits. Interestingly, participants were more accurate in overriding overtrained responses when attacks were highly familiar, possibly due to enhanced perceptual processing, although this came at the cost of longer response times. These findings introduce two complementary tools that address key limitations in current paradigms: the intra-block reversal increases habit sensitivity without inflating working memory demands, while the hands-attack task captures naturalistic habit expression without artificial training, using a single, ecologically valid session. Both are suited for clinical applications, particularly where time constraints or cognitive load limit the feasibility of traditional approaches.

Virtual Reality (VR) applications depend on eliciting spatial presence, the subjective experience of being physically located within a virtual environment. Although individual differences have long been theorised to contribute to this experience, their role in highly immersive VR systems remains contested. The present study investigated whether trait absorption predicts spatial presence and whether this relationship is mediated by attention allocation. Seventy participants (44 female, 26 male; M age = 22.90, SD = 4.88) completed a 6-minute VR session using a Meta Quest 3 Head-Mounted Display and validated self-report measures of trait absorption (Tellegen Absorption Scale), attention allocation, and spatial presence (MEC-Spatial Presence Questionnaire). Path analysis confirmed a significant, complete mediation pathway: trait absorption positively predicted attention allocation ({beta} = 0.27, p = .013), which in turn strongly predicted spatial presence ({beta} = 0.54, p < .001). The direct path from absorption to spatial presence was non-significant ({beta} = 0.11, p = .325), indicating complete mediation. The indirect effect was significant ({beta} = 0.15; 95% BCa CI [0.025, 0.291]). The model explained a sizeable 33.8% of the variance in spatial presence (Cohens f{superscript 2} = 0.51). Post-hoc dose-response analysis revealed that trait absorption acts as a cognitive amplifier: the strength of the attention-presence relationship tripled from low-absorption ({beta} = 0.33, R{superscript 2} = .15) to high-absorption individuals ({beta} = 1.00, R{superscript 2} = .56). These findings demonstrate that individual differences remain important in highly immersive VR by modulating the effectiveness of attentional focus, offering promising directions for tailoring VR interventions.

Visual false memory refers to our tendency to falsely recognize novel stimuli that are visually similar to seen stimuli. Visual false memory also occurs when stimuli are meaningful, suggesting that semantic information interferes with the encoding of visual details. However, the neural mechanisms of this semantic interference effect are largely unknown. In the present fMRI study, participants were scanned while encoding visually similar fonts presented with words (word-fonts) or pseudowords (pseudoword-fonts), and later, when recognizing old, new similar (lures), and new dissimilar (novel) fonts displayed in the same meaningless letter string. We performed (1) representational similarity analysis (RSA) at encoding to identify visual, visuosemantic, and semantic representations associated with subsequent visual true and false font recognition, (2) encoding-retrieval similarity (ERS) analysis to assess their reinstatement during retrieval, and (3) mediational analyses to examine hippocampal contributions. The study yielded three main findings. First, visuosemantic representations supported true font recognition when stored in right fusiform gyrus, but false recognition of word-fonts when stored in the left fusiform gyrus. Second, mirroring this pattern, reinstatement in right fusiform gyrus was associated with true font recognition, whereas reinstatement in left fusiform gyrus was linked to false recognition of word-fonts. Finally, posterior hippocampal activation reduced false font memory mainly for pseudoword-associated fonts via decreased reinstatement in perceptual regions, while anterior hippocampal activity increased false memory of word-fonts via enhanced reinstatement in semantic regions. Taken together, these findings reveal how distinct hippocampal-cortical pathways differentially bias memory towards perceptual specificity or semantic generalization. Significance StatementFalse memories are often triggered by visual similarity, but this study shows that meaning encoded during learning can distort memory for visual details, even when retrieval cues are meaningless. Participants learned fonts associated with words or pseudowords and judged whether similar lure fonts, shown on a meaningless letter string, were seen before. Although behavioral performance was similar across conditions, brain imaging revealed a key dissociation: the left fusiform gyrus and anterior hippocampus promote semantic generalization that increases false recognition, whereas the right fusiform gyrus and posterior hippocampus support perceptual specificity that protects against it. These findings reveal how distinct hippocampal-cortical pathways differentially bias memory toward truth or illusion.

Real-world visual search is often performed at the category level: we search for shoes or bags without knowing their exact features in advance. This requires categorical search templates that accommodate the inherent variability within the target category. Here, we examine how the variability in search templates across categories constrains visual search performance. We quantify template variability by measuring variability in object drawings from a large online dataset (Experiment 1) and from a controlled lab-based drawing task (Experiment 2) and in turn relate this variability to performance in categorical search. Across both experiments, higher category variability, and thus broader search templates, were associated with slower responses. Moreover, the observers most prioritized object template predicted their search performance better than other observers templates, indicating that individual differences in template variability shape visual search. Together, our findings demonstrate that naturalistic visual search is governed by structured variability across both object categories and observers.

Humans can flexibly acquire entirely new sensorimotor mappings, a process known as de novo motor learning. A central challenge in de novo motor learning is that the learner must discover a viable solution from scratch within a highly redundant control space, without predefined task constraints. Understanding what types of sensorimotor information contribute to the formation of accurate motor behavior in such situations is therefore critical for explaining how novel sensorimotor skills are acquired. While previous studies have suggested that novel visuomotor mappings can be formed based on movement direction and target position, it remains unclear how these two types of information contribute to the learning process. To address this question, we trained 25 human participants to learn arbitrary joystick-to-cursor mapping. We then employed a generalization paradigm to selectively restrict learning experience to either movement direction or target position. Three distinct target conditions were designed: one emphasized target position (P), another emphasized movement direction (D), and a third (P&D) encouraged learning of both components separately. As a result, direction experience improved movement initiation, whereas position experience enhanced movement termination. However, in the P&D condition, combining these experiences did not yield additive generalization. Instead, endpoint accuracy was positively correlated with the degree of alignment between direction- and position-based joystick outputs within the control space. These results suggest that accurate formation of a novel sensorimotor map depends on the coordinated use of directional and positional experiences. Significant StatementHow do humans build entirely new sensorimotor relationships from scratch? This study examined how distinct sensorimotor experiences (movement direction and target position) contribute to the acquisition of a novel joystick-to-cursor mapping. By isolating these experiences, we found that direction experience improved movement initiation, while position experience enhanced movement termination. However, combining these experiences did not lead to more accurate movements as a whole. Instead, the accuracy was related to how well directional and positional joystick outputs were aligned in a control space. These findings suggest that de novo motor learning requires the coordinated use of directional and positional information.

Pretend play is a hallmark behavior in childhood where children create nonliteral meanings. Empirical data supporting the role of social cognition and the decoupling from literality are still scarce during early development. We explored here how the comprehension of pretense affects the visual exploratory behavior of toddlers (n = 44) and adults (n = 65) when they were exposed to short video clips in which an actress performed either real actions (e.g., eating jelly) or pretend actions (e.g., pretending to eat with imaginary food), while varying the complexity of those actions. We analyzed participants exploration of the face in the videos as exploitation of social information. We showed that all observers paid more attention to the face in pretend scenarios than in real ones, measured as longer total looking time in adults and more fixations and revisits to the face in both age groups. We also found more gaze shifts (a measure of information sampling) between the face and the moving hand in the pretend videos in both age groups, mainly at the initial stages of the actions. Additionally, analyses of the scanpaths structure using gaze entropy showed less order in the exploration of pretend videos in both age groups, suggesting that pretense involved greater uncertainty and increased information seeking. The less structured trajectories were observed again mainly in complex pretend scenarios. Taken together, our gaze results indicate that from its developmental origins, the comprehension of pretense relies on social processes linked with information seeking and exploration. Significance StatementDevelopmental theories have long debated whether pretend games are born in conjunction with social capacities in the second year or become integrated later in life. Our study shows that, much like adults, toddlers visually explore pretend scenes gathering more social information and in a less structured manner compared to real-world scenarios, suggesting that the emerging capacity to play with the meaning of things is linked with that of thinking of other minds early in life.

Practice enhances motor acuity, enabling movement execution with greater speed and accuracy. However, the learning principles underlying improvements in speed, accuracy, and efficiency remain less understood than those supporting motor skill acquisition and adaptation. Here, we examined motor execution in a skill-based practice task to characterize learning, retention, and generalization of motor acuity. Using a gamified two-dimensional racing task, right-handed participants controlled a stylus-driven car along a curved track as quickly and accurately as possible. Across two studies (N = 83 total, 54 females), participants completed 300 training laps on Session 1 and returned for Session 2 to assess retention and generalization to novel track configurations: one with altered spatial configuration (rotated track) and one requiring movement in the opposite direction of training (reverse track). Movement speed improved rapidly and showed robust, though incomplete, retention across sessions. Speed improvements generalized substantially to both novel tracks. Accuracy was high at training onset and showed strong retention. However, we do not observe offline gains between sessions. Notably, accuracy declined transiently for the novel track configurations, suggesting interference from prior training. Movement efficiency, indexed by path length, was retained and generalized to the rotated track. However, reversing movement direction impaired efficiency, revealing a movement direction effect. This effect persisted when training direction was reversed in a second study, with counterclockwise movements remaining slower and less efficient than clockwise movements. These findings show that practice produces durable and broadly transferable motor execution improvements, while inherent movement direction biases constrain how improvements generalize across contexts. New & NoteworthyThe learning principles underlying improvements in motor acuity remain less well understood than those governing other forms of motor learning. Prior work suggests that motor execution improvements show limited generalization. In contrast, the present findings demonstrate that execution-based practice can produce robust, transferable gains, while also revealing a key constraint: inherent movement direction biases that limit generalization. By characterizing learning, retention, and generalization, this work provides new insight into how motor acuity improvements compare with skill acquisition and adaptation.