Goal-directed aiming under restricted viewing conditions with confirmatory sensory feedback

Planning lane changes using advance visual and haptic information

Taking a motor planning perspective, this study investigates whether haptic force cues displayed on the steering wheel are more effective than visual cues in signaling the direction of an upcoming lane change. Licensed drivers drove in a fixed-base driving simulator equipped with an active steering system for realistic force feedback. They were instructed to make lane changes upon registering a directional cue. Cues were delivered according to the movement precuing technique employing a pair of precues and imperative cues which could be either visual, haptic, or crossmodal (a visual precue with a haptic imperative cue, and vice versa). The main dependent variable was response time. Additional analyses were conducted on steering wheel angle profiles and the rate of initial steering errors. Conditions with a haptic imperative cue produced considerably faster responses than conditions with a visual imperative cue, irrespective of the precue modality. Valid and invalid precues produced the typical gains and costs, with one exception. There appeared to be little cost in response time or initial steering errors associated with invalid cueing when both cues were haptic. The results are consistent with the hypothesis that imperative haptic cues facilitate action selection while visual stimuli require additional time-consuming cognitive processing.

Interaction of hand orientations during familiarization of a goal-directed aiming task

The purpose of the present study was to examine errors for an isometric goal-directed aiming task during familiarization at different hand orientation. Interaction between neutral and pronated hand orientations with and without directional feedback would provide insights into short-term adaptations and the nature of control. In this study, 30 healthy right-handed adults (age, 22.7 ± 3.1 years; weight, 69.4 ± 16.6 kg; height, 166.7 ± 7.9 cm) were randomly assigned to neutral or pronated hand orientation conditions. To assess familiarization, participants performed ten sets (16 targets/set) of goal-directed aiming task with continuous visual feedback towards targets symmetrically distributed about the origin. Following familiarization, participants then completed eight sets; four sets with and four sets without directional feedback, in an alternated order. For both hand orientations, directional errors were reduced in the first two sets (p < 0.05), suggesting only three sets were required for familiarization. Additionally, the learning rate was also similar for both hand orientations. Following familiarization, aiming errors without feedback were significantly higher than with feedback while no change between sets was observed, regardless of hand orientation. Aiming errors were reduced in the early phase with and without visual feedback, however, in the late phase, errors were corrected when visual feedback was provided. It suggests that hand orientation does not affect familiarization, and mechanisms similar to rapid learning may be involved. It is probable that learning is consolidated during familiarization along with feedforward input to maintain performance. In addition, proprioceptive feedback plays a role in reducing errors early, while the online visual feedback plays a role in reducing errors later, independent of hand orientation.

Differentiation among bio- and augmented- feedback in technologically assisted rehabilitation

Introduction: In rehabilitation practice, the term 'feedback' is often improperly used, with augmented feedback and biofeedback frequently confused, especially when referring to the human-machine interaction during technologically assisted training. The absence of a clear differentiation between these categories represents an unmet need for rehabilitation, emphasized by the advent of new technologies making extensive use of video feedback, exergame, and virtual reality.Area covered: In this review we tried to present scientific knowledge about feedback, biofeedback, augmented feedback and neurofeedback, and related differences in rehabilitation settings, for a more proper use of this terminology. Despite the continuous expansion of the field, few researches clarify the differences among these terms. This scoping review was conducted through the searching of current literature up to May 2020, using following databases: PUBMED, EMBASE and Web of Science. After literature search a classification system, distinguishing feedback, augmented feedback, and biofeedback, was applied.Expert opinion: There is a need for clear definitions of feedback, biofeedback, augmented feedback, and neurofeedback in rehabilitation, especially in the technologically assisted one based on human-machine interaction. In fact, the fast development of new technologies requires to be based on solid concepts and on a common terminology shared among bioengineers and clinicians.