Comparing direct and indirect interaction in stroke rehabilitation

We explore the differences of direct (DI) vs. indirect (IDI) interaction in stroke rehabilitation. Direct interaction is when the patients move their arms in reaction to changes in the augmented physical environment; indirect interaction is when the patients move their arms in reaction to changes on a computer screen. We developed a rehabilitation game in both settings evaluated by a within-subject study with 10 patients with chronic stroke, aiming to answer 2 major questions: (i) do the game scores in either of the two interaction modes correlate with clinical assessment scores? and (ii) whether performance is different using direct versus indirect interaction in patients with stroke. Our experimental results confirm higher performance in use of DI over IDI. They also suggest better correlation of DI and clinical scores. Our study provides evidence for the benefits of direct interaction therapies vs. indirect computer-assisted therapies in stroke rehabilitation

Haptic Augmented Reality to monitor human arm's stiffness in rehabilitation

Augmented Reality (AR) is a live, direct or indirect, view of a physical, real-world environment whose elements are overlaid by virtual, computer generated objects. In this paper, AR is combined with haptics in order to observe human arm's stiffness. A haptic, hand-held device is used to measure the human arm's impedance. While a computer vision system tracks and records the position of the hand, a computer screen displays the impedance diagrams superimposed on the hand in a real-time video feed. The visual augmentation is also performed using a video projector that project's the diagrams on the hand as it moves. © 2012 IEEE

An assistive tabletop keyboard for stroke rehabilitation

We propose a tabletop keyboard that assists stroke patients in using computers. Using computers for purposes such as paying bills, managing bank accounts, sending emails, etc., which all include typing, is part of Activities of Daily Living (ADL) that stroke patients wish to recover. To date, stroke rehabilitation research has greatly focused on using computer-assisted technology for rehabilitation. However, working with computers as a skill that patients need to recover has been neglected. The conventional human computer interfaces are mouse and keyboard. Using keyboard stays the main challenge for hemiplegic stroke patients because typing is usually a bimanual task. Therefore, we propose an assistive tabletop keyboard which is not only a novel computer interface that is specially designed to facilitate patient-computer interaction but also a rehab medium through which patients practice the desired arm/hand functions. © 2013 Authors

A multimodal approach to understanding motor impairment and disability after stroke

Many different measures have been found to be related to behavioral outcome after stroke. Preclinical studies emphasize the importance of brain injury and neural function. However, the measures most important to human outcomes remain uncertain, in part because studies often examine one measure at a time or enroll only mildly impaired patients. The current study addressed this by performing multimodal evaluation in a heterogeneous population. Patients (n = 36) with stable arm paresis 3-6 months post-stroke were assessed across 6 categories of measures related to stroke outcome: demographics/medical history, cognitive/mood status, genetics, neurophysiology, brain injury, and cortical function. Multivariate modeling identified measures independently related to an impairment-based outcome (arm Fugl-Meyer motor score). Analyses were repeated (1) identifying measures related to disability (modified Rankin Scale score), describing independence in daily functions and (2) using only patients with mild deficits. Across patients, greater impairment was related to measures of injury (reduced corticospinal tract integrity) and neurophysiology (absence of motor evoked potential). In contrast, (1) greater disability was related to greater injury and poorer cognitive status (MMSE score) and (2) among patients with mild deficits, greater impairment was related to cortical function (greater contralesional motor/premotor cortex activation). Impairment after stroke is most related to injury and neurophysiology, consistent with preclinical studies. These relationships vary according to the patient subgroup or the behavioral endpoint studied. One potential implication of these results is that choice of biomarker or stratifying variable in a clinical stroke study might vary according to patient characteristics. © 2014 Springer-Verlag Berlin Heidelberg

Validity of Robot-based Assessments of Upper Extremity Function

Objective To examine the validity of 5 robot-based assessments of arm motor function post-stroke. Design Cross sectional. Setting Outpatient clinical research center. Participants Volunteer sample of 40 participants, age \u3e18 years, 3-6 months post-stroke, with arm motor deficits that had plateaued. Intervention None. Main Outcome Measures Clinical standards included the Fugl-Meyer Arm Motor Scale (FMA), and 5 secondary motor outcomes: hand/wrist subsection of the FMA; Action Research Arm Test (ART); Box & Blocks test (B/B); hand subscale of Stroke Impact Scale-2 (SIS); and the Barthel Index (BI). Robot-based assessments included: wrist targeting; finger targeting; finger movement speed; reaction time; and a robotic version of the (B/B) test. Anatomical measures included percentage injury to the corticospinal tract (CST) and primary motor cortex (M1, hand region) obtained from MRI . Results Subjects had moderate-severe impairment (arm FMA scores = 35.6±14.4, range 13.5-60). Performance on the robot-based tests, including speed (r=0.82, p\u3c0.0001), wrist targeting (r=0.72, p\u3c0.0001), and finger targeting (r=0.67, p\u3c0.0001) correlated significantly with the FMA scores. Wrist targeting (r=0.57 - 0.82) and finger targeting (r=0.49 - 0.68) correlated significantly with all 5 secondary motor outcomes and with percent CST injury. The robotic version of the B/B correlated significantly with the clinical B/B test but was less prone to floor effect. Robot-based assessments were comparable to FMA score in relation to percent CST injury and superior in relation to M1 hand injury. Conclusions The current findings support using a battery of robot-based methods for assessing the upper extremity motor function in subjects with chronic stroke

Haptic Augmented Reality to monitor human arm's stiffness in rehabilitation

Augmented Reality (AR) is a live, direct or indirect, view of a physical, real-world environment whose elements are overlaid by virtual, computer generated objects. In this paper, AR is combined with haptics in order to observe human arm's stiffness. A haptic, hand-held device is used to measure the human arm's impedance. While a computer vision system tracks and records the position of the hand, a computer screen displays the impedance diagrams superimposed on the hand in a real-time video feed. The visual augmentation is also performed using a video projector that project's the diagrams on the hand as it moves. © 2012 IEEE

Free-hand interaction with leap motion controller for stroke rehabilitation

In recent years, the field of Human-Computer Interaction (HCI) has been advanced with many technologies, however, most are limited to healthy users. In this paper, we leveraged the technology of free-hand interaction to rehabilitate patients with stroke. We modified the game of Fruit Ninja to use Leap Motion controller's hand tracking data for stroke patients with arm and hand weakness to practice their finger individuation. In a pilot study, we recruited 14 patients with chronic stroke to play the game using natural interaction. Their Fruit Ninja (FN) scores show high correlation with the standard clinical assessment scores such as Fugl-Meyer (FMA) and Box-and-Blocks Test (BBT) scores. This finding suggests that our freehand Fruit Ninja's score is a good indicator of the patient's hand function and therefore will be informative if used in their rehabilitation

Comparing direct and indirect interaction in stroke rehabilitation

We explore the differences of direct (DI) vs. indirect (IDI) interaction in stroke rehabilitation. Direct interaction is when the patients move their arms in reaction to changes in the augmented physical environment; indirect interaction is when the patients move their arms in reaction to changes on a computer screen. We developed a rehabilitation game in both settings evaluated by a within-subject study with 10 patients with chronic stroke, aiming to answer 2 major questions: (i) do the game scores in either of the two interaction modes correlate with clinical assessment scores? and (ii) whether performance is different using direct versus indirect interaction in patients with stroke. Our experimental results confirm higher performance in use of DI over IDI. They also suggest better correlation of DI and clinical scores. Our study provides evidence for the benefits of direct interaction therapies vs. indirect computer-assisted therapies in stroke rehabilitation

A multimodal approach to understanding motor impairment and disability after stroke

Many different measures have been found to be related to behavioral outcome after stroke. Preclinical studies emphasize the importance of brain injury and neural function. However, the measures most important to human outcomes remain uncertain, in part because studies often examine one measure at a time or enroll only mildly impaired patients. The current study addressed this by performing multimodal evaluation in a heterogeneous population. Patients (n = 36) with stable arm paresis 3-6 months post-stroke were assessed across 6 categories of measures related to stroke outcome: demographics/medical history, cognitive/mood status, genetics, neurophysiology, brain injury, and cortical function. Multivariate modeling identified measures independently related to an impairment-based outcome (arm Fugl-Meyer motor score). Analyses were repeated (1) identifying measures related to disability (modified Rankin Scale score), describing independence in daily functions and (2) using only patients with mild deficits. Across patients, greater impairment was related to measures of injury (reduced corticospinal tract integrity) and neurophysiology (absence of motor evoked potential). In contrast, (1) greater disability was related to greater injury and poorer cognitive status (MMSE score) and (2) among patients with mild deficits, greater impairment was related to cortical function (greater contralesional motor/premotor cortex activation). Impairment after stroke is most related to injury and neurophysiology, consistent with preclinical studies. These relationships vary according to the patient subgroup or the behavioral endpoint studied. One potential implication of these results is that choice of biomarker or stratifying variable in a clinical stroke study might vary according to patient characteristics. © 2014 Springer-Verlag Berlin Heidelberg