Bimanual coordination: A missing piece of arm rehabilitation after stroke

Abstract

Inability to use the arm in daily actions significantly lowers quality of life after stroke. Most contemporary post-stroke arm rehabilitation strategies that aspire to re-engage the weaker arm in functional activities have been greatly limited in their effectiveness. Most actions of daily life engage the two arms in a highly coordinated manner. In contrast, most rehabilitation approaches predominantly focus on restitution of the impairments and unilateral practice of the weaker hand alone. We present a perspective that this misalignment between real world requirements and intervention strategies may limit the transfer of unimanual capability to spontaneous arm use and functional recovery. We propose that if improving spontaneous engagement and use of the weaker arm in real life is the goal, arm rehabilitation research and treatment need to address the coordinated interaction between arms in targeted theory-guided interventions. Current narrow focus on unimanual deficits alone, difficulty in quantifying bimanual coordination in real-world actions and limited theory-guided focus on control and remediation of different coordination modes are some of the biggest obstacles to successful implementation of effective interventions to improve bimanual coordination in the real world. We present a theory-guided taxonomy of bimanual actions that will facilitate quantification of coordination for different real-world tasks and provide treatment targets for addressing coordination deficits. We then present evidence in the literature that points to bimanual coordination deficits in stroke survivors and demonstrate how current rehabilitation approaches are limited in their impact on bimanual coordination. Importantly, we suggest theory-based areas of future investigation that may assist quantification, identification of neural mechanisms and scientifically-based training/remediation approaches for bimanual coordination deficits post-stroke. Advancing the science and practice of arm rehabilitation to incorporate bimanual coordination will lead to a more complete functional recovery of the weaker arm, thus improving the effectiveness of rehabilitation interventions and augmenting quality of life after stroke.

Bimanual motor skill learning after stroke: Combining robotics and anodal tDCS over the undamaged hemisphere: An exploratory study

“…The baseline performances on the CIRCUIT were superior in healthy individuals compared to patients for biSAT and biCO, as expected since bimanual coordination is impaired after stroke ( 4 , 5 , 13 , 58 , 59 ). By contrast, biFOP, which quantifies the amount of force “wasted” against the virtual walls, was not significantly different.…”

Bimanual motor skill learning after stroke: Combining robotics and anodal tDCS over the undamaged hemisphere: An exploratory study

“…The baseline performances on the CIRCUIT were superior in healthy individuals compared to patients for biSAT and biCO, as expected since bimanual coordination is impaired after stroke ( 4 , 5 , 13 , 58 , 59 ). By contrast, biFOP, which quantifies the amount of force “wasted” against the virtual walls, was not significantly different.…”

Hand forces and placement are modulated and covary during anticipatory control of bimanual manipulation

“…Further studies could explore the mechanical aspects of this type of bimanual control. The neural underpinnings of bimanual control are less understood than unimanual grasping (Le and Niemeier 2013) but suggest that a neural network exists for bimanual coordination (Gerloff and Andres 2002;Kantak et al 2017;Santello et al 2013;Theorin and Johansson 2007;Vinjamuri et al 2008). Together with previous studies, the present findings suggest that the modulation and covariation of forces and placement are general features that exist across multiple effectors (two-digit, three-digit, whole hand, bimanual).…”

Shared control–based bimanual robot manipulation

“…Previous work has successfully isolated a set of control semantics in the brains of rhesus monkeys using surgically implanted electrodes to activate their bimanual actions (34). We argue that if the brain has a representation of central bimanual actions that it uses to organize the interactions, constraints, cooperative movements, and asymmetric movements between the user's hands, a theory supported by much previous work (3,35,42,40), then we should be able to isolate, recognize, and label such features as distinct patterns in the user's hand motions when performing bimanual tasks. To explore this premise, we first conducted a formative study in which we recorded and analyzed the hand motions of human participants through various bimanual tasks.…”

Bimanual motor skill learning after stroke: Combining robotics and anodal tDCS over the undamaged hemisphere: An exploratory study

“…The baseline performances on the CIRCUIT were superior in healthy individuals compared to patients for biSAT and biCO, as expected since bimanual coordination is impaired after stroke ( 4 , 5 , 13 , 58 , 59 ). By contrast, biFOP, which quantifies the amount of force “wasted” against the virtual walls, was not significantly different.…”

Hand forces and placement are modulated and covary during anticipatory control of bimanual manipulation

“…Further studies could explore the mechanical aspects of this type of bimanual control. The neural underpinnings of bimanual control are less understood than unimanual grasping (Le and Niemeier 2013) but suggest that a neural network exists for bimanual coordination (Gerloff and Andres 2002;Kantak et al 2017;Santello et al 2013;Theorin and Johansson 2007;Vinjamuri et al 2008). Together with previous studies, the present findings suggest that the modulation and covariation of forces and placement are general features that exist across multiple effectors (two-digit, three-digit, whole hand, bimanual).…”

Shared control–based bimanual robot manipulation

“…Previous work has successfully isolated a set of control semantics in the brains of rhesus monkeys using surgically implanted electrodes to activate their bimanual actions (34). We argue that if the brain has a representation of central bimanual actions that it uses to organize the interactions, constraints, cooperative movements, and asymmetric movements between the user's hands, a theory supported by much previous work (3,35,42,40), then we should be able to isolate, recognize, and label such features as distinct patterns in the user's hand motions when performing bimanual tasks. To explore this premise, we first conducted a formative study in which we recorded and analyzed the hand motions of human participants through various bimanual tasks.…”

Bimanual motor skill learning after stroke: Combining robotics and anodal tDCS over the undamaged hemisphere: An exploratory study

“…The baseline performances on the CIRCUIT were superior in healthy individuals compared to patients for biSAT and biCO, as expected since bimanual coordination is impaired after stroke ( 4 , 5 , 13 , 58 , 59 ). By contrast, biFOP, which quantifies the amount of force “wasted” against the virtual walls, was not significantly different.…”

Hand forces and placement are modulated and covary during anticipatory control of bimanual manipulation

“…Further studies could explore the mechanical aspects of this type of bimanual control. The neural underpinnings of bimanual control are less understood than unimanual grasping (Le and Niemeier 2013) but suggest that a neural network exists for bimanual coordination (Gerloff and Andres 2002;Kantak et al 2017;Santello et al 2013;Theorin and Johansson 2007;Vinjamuri et al 2008). Together with previous studies, the present findings suggest that the modulation and covariation of forces and placement are general features that exist across multiple effectors (two-digit, three-digit, whole hand, bimanual).…”

Shared control–based bimanual robot manipulation

“…Previous work has successfully isolated a set of control semantics in the brains of rhesus monkeys using surgically implanted electrodes to activate their bimanual actions (34). We argue that if the brain has a representation of central bimanual actions that it uses to organize the interactions, constraints, cooperative movements, and asymmetric movements between the user's hands, a theory supported by much previous work (3,35,42,40), then we should be able to isolate, recognize, and label such features as distinct patterns in the user's hand motions when performing bimanual tasks. To explore this premise, we first conducted a formative study in which we recorded and analyzed the hand motions of human participants through various bimanual tasks.…”