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PLoS Computational Biology Sep 2021Decisions as to whether to continue with an ongoing activity or to switch to an alternative are a constant in an animal's natural world, and in particular underlie...
Decisions as to whether to continue with an ongoing activity or to switch to an alternative are a constant in an animal's natural world, and in particular underlie foraging behavior and performance in food preference tests. Stimuli experienced by the animal both impact the choice and are themselves impacted by the choice, in a dynamic back and forth. Here, we present model neural circuits, based on spiking neurons, in which the choice to switch away from ongoing behavior instantiates this back and forth, arising as a state transition in neural activity. We analyze two classes of circuit, which differ in whether state transitions result from a loss of hedonic input from the stimulus (an "entice to stay" model) or from aversive stimulus-input (a "repel to leave" model). In both classes of model, we find that the mean time spent sampling a stimulus decreases with increasing value of the alternative stimulus, a fact that we linked to the inclusion of depressing synapses in our model. The competitive interaction is much greater in "entice to stay" model networks, which has qualitative features of the marginal value theorem, and thereby provides a framework for optimal foraging behavior. We offer suggestions as to how our models could be discriminatively tested through the analysis of electrophysiological and behavioral data.
Topics: Animals; Decision Making; Feeding Behavior; Food Preferences; Models, Theoretical; Neurons; Psychomotor Performance; Taste
PubMed: 34555012
DOI: 10.1371/journal.pcbi.1009012 -
Scientific Reports May 2021The successful completion of complex tasks like hanging a picture or laparoscopic surgery requires coordinated motion of more than two limbs. User-controlled...
The successful completion of complex tasks like hanging a picture or laparoscopic surgery requires coordinated motion of more than two limbs. User-controlled supernumerary robotic limbs (SL) have been proposed to bypass the need for coordination with a partner in such tasks. However, neither the capability to control multiple limbs alone relative to collaborative control with partners, nor how that capability varies across different tasks, is well understood. In this work, we present an investigation of tasks requiring three-hands where the foot was used as an additional source of motor commands. We considered: (1) how does simultaneous control of three hands compare to a cooperating dyad; (2) how this relative performance was altered by the existence of constraints emanating from real or virtual physical connections (mechanical constraints) or from cognitive limits (cognitive constraints). It was found that a cooperating dyad outperformed a single user in all scenarios in terms of task score, path efficiency and motion smoothness. However, while the participants were able to reach more targets with increasing mechanical constraints/decreasing number of simultaneous goals, the relative difference in performance between a dyad and a participant performing trimanual activities decreased, suggesting further potential for SLs in this class of scenario.
Topics: Adult; Female; Foot; Hand; Humans; Laparoscopy; Psychomotor Performance; Robotics; Task Performance and Analysis; User-Computer Interface
PubMed: 33947906
DOI: 10.1038/s41598-021-88862-9 -
ELife Jul 2022To generate the next eye movement, oculomotor circuits take into consideration the physical salience of objects in view and current behavioral goals, exogenous and...
To generate the next eye movement, oculomotor circuits take into consideration the physical salience of objects in view and current behavioral goals, exogenous and endogenous influences, respectively. However, the interactions between exogenous and endogenous mechanisms and their dynamic contributions to target selection have been difficult to resolve because they evolve extremely rapidly. In a recent study (Salinas et al., 2019), we achieved the necessary temporal precision using an urgent variant of the antisaccade task wherein motor plans are initiated early and choice accuracy depends sharply on when exactly the visual cue information becomes available. Empirical and modeling results indicated that the exogenous signal arrives ∼80 ms after cue onset and rapidly accelerates the (incorrect) plan toward the cue, whereas the informed endogenous signal arrives ∼25 ms later to favor the (correct) plan away from the cue. Here, we scrutinize a key mechanistic hypothesis about this dynamic, that the exogenous and endogenous signals act at different times and independently of each other. We test quantitative model predictions by comparing the performance of human participants instructed to look toward a visual cue or away from it under high urgency. We find that, indeed, the exogenous response is largely impervious to task instructions; it simply flips its sign relative to the correct choice, and this largely explains the drastic differences in psychometric performance between the two tasks. Thus, saccadic choices are strongly dictated by the alignment between salience and behavioral goals.
Topics: Eye Movements; Humans; Photic Stimulation; Psychomotor Performance; Reaction Time; Saccades
PubMed: 35894379
DOI: 10.7554/eLife.76964 -
Psychological Research Jun 2024In the past few decades, binding and retrieval mechanisms have gained increased interest in research on human action control. Recent studies show that these mechanisms...
In the past few decades, binding and retrieval mechanisms have gained increased interest in research on human action control. Recent studies show that these mechanisms also play a role in the control of multiple independent actions. Here, two or more successively executed responses seem to be bound to each other so that repeating one of them can retrieve the other, affecting performance in this second response and resulting in so-called response-response binding effects. Binding effects are typically found in the response time data and, somewhat less reliably, also in the error rates. Whether binding effects show in the response times, the error rates, or both, is likely influenced by the current speed-accuracy settings of the participants, with binding effects more likely showing in error rates under a speed setting, while more likely showing in RTs under an accuracy setting. Alternatively, different speed-accuracy settings might also entail changes in executive control, affecting the size of observed binding effects. In this study, we tested these assumptions by comparing binding effects under different speed-accuracy settings that were induced via instructions focusing on speed, accuracy, or both (ambivalent). Binding effects were observed in response times independent of instructions, while in error rates, they only showed under speed or ambivalent instructions. These findings indicate that binding effects can be affected by instructions regarding speed and accuracy.
Topics: Humans; Reaction Time; Psychomotor Performance; Male; Female; Adult; Executive Function; Young Adult
PubMed: 38337124
DOI: 10.1007/s00426-024-01927-y -
Child Development Sep 2019We investigated the real-time cascade of postural, visual, and manual actions for object prehension in 38 6- to 12-month-old infants (all independent sitters) and eight...
We investigated the real-time cascade of postural, visual, and manual actions for object prehension in 38 6- to 12-month-old infants (all independent sitters) and eight adults. Participants' task was to retrieve a target as they spun past it at different speeds on a motorized chair. A head-mounted eye tracker recorded visual actions and video captured postural and manual actions. Prehension played out in a coordinated sequence of postural-visual-manual behaviors starting with turning the head and trunk to bring the toy into view, which in turn instigated the start of the reach. Visually fixating the toy to locate its position guided the hand for toy contact and retrieval. Prehension performance decreased at faster speeds, but quick planning and implementation of actions predicted better performance.
Topics: Adolescent; Female; Hand; Humans; Infant; Male; Motor Skills; Posture; Psychomotor Performance; Young Adult
PubMed: 31325171
DOI: 10.1111/cdev.13282 -
Journal of Experimental Psychology.... Jun 2023To steer a vehicle, humans must process incoming signals that provide information about their movement through the world. These signals are used to inform motor control...
To steer a vehicle, humans must process incoming signals that provide information about their movement through the world. These signals are used to inform motor control responses that are appropriately timed and of the correct magnitude. However, the perceptual mechanisms determining how drivers process visual information remain unclear. Previous research has demonstrated that when steering toward a straight road-line, drivers accumulate perceptual evidence (error) over time to initiate steering action (Accumulator framework), rather than waiting for perceptual evidence to surpass time-independent fixed thresholds (Threshold framework). The more general case of steering around bends (with a requirement that the trajectory is adjusted to match the road curvature ahead) provides richer continuously varying information. The current experiment aims to establish whether the Accumulator framework provides a good description of human responses when steering toward curved road-lines. Using a computer-generated steering correction paradigm, drivers (N = 11) steered toward intermittently appearing curved road-lines that varied in position and radius with respect to the driver's trajectory. The Threshold framework predicted that steering responses would be of fixed magnitude and at fixed absolute errors across conditions regardless of the rate of error development. Conversely, the Accumulator framework predicted that drivers should respond to larger absolute errors when the error signal developed at a faster rate. Results were consistent with an Accumulator framework in a manner that supports previous investigations and the computational modeling literature. We propose that the accumulation of perceptual evidence captures human behavior in a variety of steering contexts that drivers face in the real world. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
Topics: Humans; Psychomotor Performance; Automobile Driving; Movement; Computer Simulation
PubMed: 37276122
DOI: 10.1037/xhp0001101 -
Journal of Experimental Psychology.... Feb 2020Automaticity can be established by consistently reinforcing contingencies during practice. During reinforcement learning, however, new relations can also be derived,...
Automaticity can be established by consistently reinforcing contingencies during practice. During reinforcement learning, however, new relations can also be derived, which were never directly reinforced. For instance, reinforcing the overlapping contingencies A → B and A → C, can lead to a new relation B-C, which was never directly reinforced. Across 5 experiments we investigated if such derived relations can also induce automatic effects. We first trained participants to derive a relation between a nonsense word and a color word, and then used the nonsense words as distractors in a Stroop task. Results indicate that derived color-word associates induce Stroop effects. This effect, however, is present only when sufficient attention is allocated to the distractor words during the Stroop task, and is driven by a response conflict. We conclude that, under the present training conditions, derived color-word associates became related to the corresponding color word at the lexical level, but did not gain direct access to the corresponding semantic color representation. (PsycINFO Database Record (c) 2020 APA, all rights reserved).
Topics: Adult; Attention; Executive Function; Female; Humans; Male; Psychomotor Performance; Stroop Test; Thinking
PubMed: 31192680
DOI: 10.1037/xlm0000724 -
Applied Ergonomics Sep 2023We examined the impact of performing a tone counting task of varying cognitive loads and mathematical calculations simultaneously, compared to performance on the same...
We examined the impact of performing a tone counting task of varying cognitive loads and mathematical calculations simultaneously, compared to performance on the same tasks done individually. Participants performed continuous mathematical calculations, performed a high and a low cognitive load tone counting task, and also performed the math and counting tasks simultaneously. Performing the two tasks together resulted in significant dual-task interference. We also compared these results to previous studies employing the tone counting tasks with physically demanding tasks (climbing, kayaking and running). The interference between tone counting and mathematical calculations was worse than the interference between tone counting and running and kayaking. For climbing, the difference in interference was more nuanced with evidence indicating climbing uniquely asserts task prioritization. These findings have implications for operations requiring dual or multi-tasking.
Topics: Humans; Psychomotor Performance; Running; Cognition; Task Performance and Analysis
PubMed: 37216771
DOI: 10.1016/j.apergo.2023.104052 -
ENeuro 2022The human sensorimotor system is sensitive to both limb-related prediction errors and task-related performance errors. Prediction error signals are believed to drive...
The human sensorimotor system is sensitive to both limb-related prediction errors and task-related performance errors. Prediction error signals are believed to drive implicit refinements to motor plans. However, an understanding of the mechanisms that performance errors stimulate has remained unclear largely because their effects have not been probed in isolation from prediction errors. Diverging from past work, we induced performance errors independent of prediction errors by shifting the location of a reach target but keeping the intended and actual kinematic consequences of the motion matched. Our first two experiments revealed that rather than implicit learning, motor adjustments in response to performance errors reflect the use of deliberative, volitional strategies. Our third experiment revealed a potential dissociation of performance-error-driven strategies based on error size. Specifically, behavioral changes following large errors were consistent with goal-directed or model-based control, known to be supported by connections between prefrontal cortex and associative striatum. In contrast, motor changes following smaller performance errors carried signatures of model-free stimulus-response learning, of the kind underpinned by pathways between motor cortical areas and sensorimotor striatum. Across all experiments, we also found remarkably faster re-learning, advocating that such "savings" is associated with retrieval of previously learned strategic error compensation and may not require a history of exposure to limb-related errors.
Topics: Adaptation, Physiological; Biomechanical Phenomena; Humans; Learning; Psychomotor Performance; Task Performance and Analysis
PubMed: 35110383
DOI: 10.1523/ENEURO.0371-21.2022 -
Journal of Experimental Psychology.... Oct 2019The transition from goal-directed to habitual forms of instrumental behavior is determined by variables such as the amount of training, schedules of reinforcement, the...
The transition from goal-directed to habitual forms of instrumental behavior is determined by variables such as the amount of training, schedules of reinforcement, the availability of choices, and exposure to drugs of abuse. Less is known about the control of goal-directed behavior when reinforcement is delayed rather than immediate. In these experiments, we investigated in rats the role of response-outcome contiguity on the control of goal-directed action, assessed through satiety-specific outcome devaluation tests. In Experiment 1 using a within-subjects design we observed goal-directed behavior after 6 days of FR1 training when the outcome was presented immediately following the lever press, but not when it was delayed for 20 s, revealing habit formation with delayed outcomes. Experiment 2 revealed that the habitual control observed with 20-s delays of reinforcement can be prevented if, immediately before each instrumental training session, the rats were exposed to the experimental context in the absence of both the lever and reinforcement. In summary, these experiments suggest that response-outcome contiguity plays an important role in the control of goal-directed actions and habits. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
Topics: Animals; Behavior, Animal; Conditioning, Operant; Goals; Habits; Male; Psychomotor Performance; Rats; Reward
PubMed: 31368767
DOI: 10.1037/xan0000221