Forward modeling allows feedback control for fast reaching movements

“…initial, fast phase during which the hand or other structure of interest is rapidly transported to the vicinity of the target and the later, slow, accurate phase during which movement velocity slows and accurate placement of the structure is achieved (Desmurget & Grafton, 2000; Hoff & Arbib, 1993).”

“People may use internal predictive models to generate goal-directed actions (Desmurget & Grafton, 2000).”

“…humans predict sensory consequences instead of waiting for their real Asolutionfor a fast prediction of the real feedback could be provided by a forward model (Miall et al., 1993; Desmurget and Grafton,2000) as forward models can be used to determine spatial location when joint angles are given.”

“Once an action is selected and initiated, control comes into place to detect and potentially correct any spatial mismatch between the current course of the action and the target (e.g., Desmurget & Grafton, 2000; Proteau, Boivin, Linossier, & Abahnini, 2000).”

“Thus, the question whether movement control is monotonic or nonmonotonic (e.g., Ghafouri & Feldman, 2001; Sergio et al., 2005) or continuous vs. phasic (e.g., Desmurget & Grafton, 2000) may be answered differently depending on the length of the movement path and/or the duration of the movement.”

“Furthermore, rather than having an absolute time point at which there is an abrupt shift from automatic control to “conscious” control these data imply that this shift is a gradual one that is likely inXuenced by the speed with which sensory feedback loops can sample information from an ongoing movement in order to ac…”

“It helps us plan both the saccades that will move the eyes so that the desired objects project onto the foveae and the reaching movements themselves (Desmurget & Grafton, 2000) and can also help guide the early portions of goal-directed movements when the movements begin prior to target fixation,…”

“…is classically considered the cradle of predictive mechanisms where skilled motor action is planned (Kinoshita, Oku, Hashikawa, & Nishimura, 2000), sensory consequences of movement are predicted (Blakemore, Frith, & Wolpert, 2001), and online correction is processed (Desmurget & Grafton, 2000).”

“…J. T. Enns Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver, BC, Canada V6T 1Z4 compared to the current target location, has been proposed to mediate these online corrections (Desmurget et al. 1999; Desmurget and Grafton 2000; Desmurget and Grafton 2003).”

“…data on eye-hand coordination (see Carey 2000), but also because oculomotor coding of positions would provide an efficient way of controlling hand transport relative to an internal model, allowing for fast reaching movements with minimal feedforward planning (Desmurget and Grafton 2000).”

“These delays are known to vary across modalities in the order of approximately 200 ms (Desmurget & Grafton, 2000; Miall & King, 2008; Miall, Weir, Wolpert, & Stein, 1993; von Hofsten, 2009).”

“Feedback control transfers sensory information not only into corrective adjustment of ongoing movement, but also into adjustment of motor output from the cerebral cortex.(13,50) The present results suggest that sensory information through the cerebellar motor control system is disrupted, and failure in integration of…”

“…parietal lobule, and the inferior frontal gyrus, has been linked to perception of actions and understanding intentions utilizing embodied cognition (Grafton et al., 1996; Desmurget and Grafton, 2000; Rizzolatti and Craighero, 2004; Rizzolatti and Sinigaglia, 2007, 2008; Desmurget et al., 2009).”

“Specifically, it would point to the involvement of higherorder associative regions, such as the superior parietal lobule, which is known to integrate visual, somatosensory, and efferent signals from motor areas to provide an integrated estimate of the state of the body (Kalaska, 1996; Desmurget and Grafton, 2000; Graz…”

“If the 3D joint kinematics is indeed planned before the calculation of the muscle forces that are needed while taking into account the expected upcoming interactional forces, the existence of a forward internal model is presumed (Desmurget and Grafton 2000; Weiss and Jeannerod 1998). This internal model anticipates th…”

“There are however many reports of improvement of overall performance metrics in the presence of feedback, even though no distinct changes occur in the kinematic profiles [15, 19, 49].”

“…with the view that the phylogenetic emergence of higher-order cognitive abilities were built upon the evolutionary platform provided by the motor system (Barton, 2012), particularly 3 with respect to estimating the future state of the environment and physical body (Desmurget & Grafton, 2000).”

“Anytime during movement preparation or execution, humans may update the motor plan when the object shifts or rotates (Desmurget and Grafton, 2000).”

“Importantly, these regions are implicated in the continuous online control of action (Desmurget et al. 1999; Desmurget and Grafton 2000), especially for tasks that require continuous visuospatial information.”

“Yet, no motor plans are thought to exist for actions requiring a correction online, such as the CA (Desmurget et al. 1999; Desmurget and Grafton 2000; Prablanc and Martin 1992; Prablanc et al. 2003), or for unnatural actions, such as the UA, that strongly diverge from the canonical action…”

“As such, planning of the desired timing template may be used to generate expected sensory consequences, to which subsequently the actual sensory consequences can be compared (Desmurget & Grafton, 2000; Wolpert & Ghahramani, 2000).”

“The action command is then reWned online, once the eyes acquire the target (Desmurget and Grafton 2000; Gribble et al. 2002).”

“…and intentions to low-level motor commands and signals [48,89–92], and can provide a framework for mapping between different levels of control and representation [93], as well as for integrating multiple sources of information, such as visual, proprioceptive, tactile, and emotional cues [94,95].”

“In general, optimal movement control likely reflects a combination of both feedback and feedforward processes [10].”

“When a mismatch occurs between the motor predictions and actual sensory feedback, error signals are thought to be generated in order to correct/modulate the initial movement plan (Miall et al., 1993; Wolpert, 1997; Wolpert et al., 1998a,b; Desmurget et al., 1999; Desmurget and Grafton, 2000; Todorov and Jordan, 2002;…”

“It has been suggested that the parietal lobe is a site for the formation of forward and inverse internal models of sensorimotor control (Wolpert and Kawato, 1998; Desmurget and Grafton, 2000; Della-Maggiore et al., 2004), processes important for speech motor learning.”

“Most well-known models such as the “feedforward models” assume that when motor commands are planned, the outcome of the movement is predicted by the current position of the limbs (Desmurget and Grafton, 2000).”

“FORWARD INTERNAL MODELS FOR ACTION IN MAJOR DEPRESSION Forward internal models mimic the causal flow of the physical process by predicting the consequences (e.g., position, velocity) of a motor command (Wolpert and Miall, 1996; Desmurget and Grafton, 2000; Wolpert and Flanagan, 2001).”

“…the brain makes rapid, unconscious corrections during the execution of the movement to ensure that the limb reaches the correct endpoint (Blakemore and Sirigu, 2003; Desmurget and Grafton, 2000; Feys et al, 2006; Johansson and Cole, 1992; Khan et al, 2006; Solaro et al, 2007; Winstein et al, 1997).”

“…has been interpreted as evidence for an internal forward model (e.g., Kawato, 1999; Miall & Wolpert, 1996), which uses an efferent copy of the motor command to predict the current state of an effector, which could compensate for sensory delays in feedback processing (Desmurget & Grafton, 2000).”

“Borrowing from recent models of motor control (Wolpert et al., 1995; Miall and Wolpert, 1996; Wolpert et al., 1998; Desmurget and Grafton, 2000; Wolpert and Ghahramani, 2000), it has been argued that error detection during piano performance is based on internal forward models.”

“…then this movement can be divided into two phases: (a) the initial impulse phase, consisting of the primary movement of the limb toward the target; and (b) the online control phase, consisting of the use of visual feedback to correct the limb trajectory (Desmurget & Grafton, 2000; Woodworth, 1899).”

“1990; Mourselas and Granat 1998; Ding et al. 2000; Kebaetse et al. 2001, 2005). Early studies suggested that the catch-like effect might be invoked to this end (Binder-Macleod and Barker 1991), the main rationale here being, to produce activation sequences that avoid the induction of fatigue in muscle while maximizing…”

“The parietal lobe is thought to associate with multisensory integration, which is a site for the formation of forward and feedback internal models of action control (Della-Maggiore & V, 2004; Desmurget & Grafton, 2000).”

“Exercise complexity Two possible sources: (i) Mechanical load, which included exercise variations that required greater arm elevation angles or the use of weights;(ii) Task or motor planning-control difficulty, which involved tasks and exercises in which it is necessary to incorporate both feedforward and feedback mec…”

“Thus, the upweighting of visual feedback, which is a relatively slow sensory system and thus is less effective at higher frequencies (reviewed in Desmurget & Grafton 2000), was unable to fully compensate for the loss of vestibular feedback during these tasks.”

“Hence, Frontiers in Psychology | www.frontiersin.org 5 January 2021 | Volume 11 | Article 574396 tapping may be considered as a cognitive task that requires the continuous updating of motor commands by feedback loops (Desmurget and Grafton, 2000; Guigon et al., 2008).”

“Visual feedback of one’s hands plays an important role to control pointing or grasping movements [29]–[31].”

“These designed primitives underpin the proposed modularized A 2 ML. Rule 2 : Human arm motion can be planned and controlled in both of the joint and Cartesian spaces [42, 43].”

“…that there is no fundamental difference between the conditions with and without target perturbation (Pélisson, Prablanc, Goodale, & Jeannerod, 1986; Desmurget & Grafton, 2000); in both cases, the system estimates its state (using sensory feedback and internal prediction) to correct errors and move…”

“Multiple studies over the last decades have proposed that humans use forward models to predict the sensory outcomes of not just self-generated movements (Wolpert et al., 1995; Desmurget and Grafton, 2000; Christensen et al., 2007; Miall et al., 2007) but also visually (Kilner et al.”

“Anytime during movement preparation or execution, humans may update the motor plan when the object shifts or rotates [4].”

“Forward models are internal models by which the central nervous system (CNS) represents the causal relationship between actions and their consequences (i.e., motor-to-sensory transformation) (Desmurget & Grafton, 2000; Wolpert & Miall, 1996).”

“Some of them are related to the immediate control of action: for example, actual stimuli can be replaced when the sensors are unavailable or unreliable [19].”

“by the body of the agent [21], producing a reference signal for the control of voluntary acts [1].”

“In contrast, humans reason about actions through an internal understanding of geometry and dynamics, anticipating how their embodiment and surrounding objects will move, deform, or make contact in response to actions [15, 19, 25, 39, 58].”

“Impor-tantly, such efference copying can take place internally, before an action becomes overt (e.g., Blakemore & Sirigu, 2003; Desmurget & Grafton, 2000), and is found for motor and mental actions, including language (e.g., Argyropoulos, 2016; Ito, 2008; Lesage et al., 2017; Moberget et al., 2014).”

“Indeed, motor commands can also be used to estimate position and motion states (Desmurget & Grafton, 2000; Gandevia, 2014; Gandevia et al., 2006; Smith et al., 2009).”

“Frontal and parietal cortices are likely involved with state estimation where proprioceptive and visual feedback are integrated into a common limb estimate (Desmurget and Grafton, 2000; Shadmehr and Krakauer, 2008; Scott, 2012; Takei et al., 2021).”

“Fast goal-directed movements, such as those performed in our study (140–240 ms), are primarily controlled by preplanned descending cortical commands that are not influenced by online sensory or visual feedback (Desmurget and Grafton 2000; Gordon and Ghez 1987; Seidler et al. 2004; Shadmehr et al. 2010).”

“This implies that the CNS can predict movement outcome thanks to an internal model of the motor apparatus (Miall and Wolpert, 1996; Desmurget and Grafton, 2000).”

“…skilled performance, error-monitoring does not rely on external feedback but is mainly guided by internal, feed-forward models of the motor plan (Desmurget and Grafton, 2000; Wolpert and Miall, 1996; Wolpert et al., 1995), which enables fast error-correction processes (Rabbitt, 1966;…”

“Humans use both feedback and feedforward when sending out motor commands [1].”

“movements despite delays in the loop (Desmurget and Grafton 2000).”

“Here, feedback control is mainly involved, and visual as well as proprioceptive information is processed to a large extent (Desmurget and Grafton, 2000).”

“From computational models of the morphology of white matter structures, it was observed that crucial areas, as the superior parietal lobe (SPL) and others in the PPC were more prone to damage in DAI following concussion [3].”

“To explain the visualguided reaching movement mechanism, different models have been proposed, including feedforward, feedback, and hybrid models, and there has been an ongoing controversy among these three models [21].”

“And, perhaps most importantly, there is growing evidence that human movement does not rely on fully pre-planned trajectories, at least for limb control (Sergio and Scott, 1998; Desmurget and Grafton, 2000; Nashed et al., 2012).”

“During sustained sensorimotor action, the integrity of sensorimotor feedback processes responsible for the online translation of sensory error information into corrective motor action is tested (Desmurget and Grafton, 2000; Vaillancourt et al., 2003).”

“A common strategy employed in manual aiming tasks is to reach a ‘‘fast but safe” zone under feed-forward control to a point as close as possible to the target and then accurately reach the point of destination using online feedback control (Desmurget and Grafton, 2000).”