Reach-to-Grasp: A Multisensory Experience

Abstract

The reach-to-grasp movement is ordinarily performed in everyday living activities and it represents a key behavior that allows humans to interact with their environment. Remarkably, it serves as an experimental test case for probing the multisensory architecture of goal-oriented actions. This review focuses on experimental evidence that enhances or modifies how we might conceptualize the “multisensory” substrates of prehension. We will review evidence suggesting that how reach-to-grasp movements are planned and executed is influenced by information coming from different sensory modalities such as vision, proprioception, audition, taste, and olfaction. The review closes with some considerations about the predominant role of the multisensory constituents in shaping prehensile behavior and how this might be important for future research developments, especially in the rehabilitative domain.

Hierarchical Human-Inspired Control Strategies for Prosthetic Hands

“…The examined approaches show some common critical points: The subject, through EMG signals, can only choose the grasp type but the simplicity of this functionality requires special attention when the hand starts closing because the closure velocity applied before touch [ 124 ] could cause the object to go out of the grasping area [ 125 ]; A reach phase where the subject can voluntarily control the fingers during the object approach is missing ( Section 5 ); Without a reaching phase, predetermined configurations are necessary for the pre-shaping phase not usable with a great number of objects (or shapes) [ 126 ]; Except for the SAMS, in the other approaches the increase of the force during the automatic control is not possible; The force reference is obtained based on tests performed for one or a few levels of objects weights and they cannot be changed. A coordination strategy among the fingers to ensure the grasp stability is missing.…”

“…Without a reaching phase, predetermined configurations are necessary for the pre-shaping phase not usable with a great number of objects (or shapes) [ 126 ];…”

“…In the middle-level (corresponding to AIP, IPL, FR, PMv areas, the core region in the dorsomedial pathway and some regions between the two pathways code reaching information, Section 5 ), the pre-shaping activates only the involved fingers and then close them with a gradual increment of the position, up to reach the object surface (position control performed by the user) [ 126 ]. Analogously, in this phase it is also possible to open the hand.…”

Concurrent Multimodal Data Acquisition During Brain Scanning is within Reach

“…The design of these methods improves previous methodologies used in visuomotor brain mapping by enabling the impartial exploration of neural activity associated with visual, motor, visuomotor, or oculomotor processes with the highest spatiotemporal resolution currently available. This will provide a more accurate multimodal view of grasping processes (Betti, Castiello, & Begliomini, 2021). Subsequently, associated brain analysis may classify neural signatures into those more related to visual properties, hand movements, or eye movements, and outline which factors influence their individual contributions and interactions (Guo, Nestor, Nemrodov, Frost, & Niemeier, 2019).…”

Multisensory information about changing object properties can be used to quickly correct predictive force scaling for object lifting

“…Because of time constraints in online control, not only the accuracy but also the delay of information is important (Crevecoeur et al 2016). It is known that inputs from multiple senses are used for hand shaping (see for a recent review: Betti et al 2021) and object lifting (van Polanen et al 2019) and can even improve object grasping (Camponogara and Volcic 2019b). Less is clear about the specific weighting of visual and haptic information.…”