A Case Study of the Validity of Web-based Visuomotor Rotation Experiments.

Web-based experiments are gaining momentum in motor learning research because of the desire to increase statistical power, decrease overhead for human participant experiments, and utilize a more demographically inclusive sample population. However, there is a vital need to understand the general feasibility and considerations necessary to shift tightly controlled human participant experiments to an online setting. We developed and deployed an online experimental platform modeled after established in-laboratory visuomotor rotation experiments to serve as a case study examining remotely collected data quality for an 80-min experiment. Current online motor learning experiments have thus far not exceeded 60 min, and current online crowdsourced studies have a median duration of approximately 10 min. Thus, the impact of a longer-duration, web-based experiment is unknown. We used our online platform to evaluate perturbation-driven motor adaptation behavior under three rotation sizes (±10°, ±35°, and ±65°) and two sensory uncertainty conditions. We hypothesized that our results would follow predictions by the relevance estimation hypothesis. Remote execution allowed us to double (n = 49) the typical participant population size from similar studies. Subsequently, we performed an in-depth examination of data quality by analyzing single-trial data quality, participant variability, and potential temporal effects across trials. Results replicated in-laboratory findings and provided insight on the effect of induced sensory uncertainty on the relevance estimation hypothesis. Our experiment also highlighted several specific challenges associated with online data collection including potentially smaller effect sizes, higher data variability, and lower recommended experiment duration thresholds. Overall, online paradigms present both opportunities and challenges for future motor learning research.

Use of High Condylectomy and Abdominal Dermis Fat Grafting for an Acromegaly Induced Bilateral Condylar Hyperplasia: A Case Report.

Acromegaly is a disorder characterized by hypersecretion of growth hormone, resulting in morbidities associated with multiple systems. Although most of the morbidities are reversed following control of the underlying disease, it may take several weeks to months for the symptoms to subside. One of the most noticeable effects of acromegaly is changes in facial features and jawbone growth, which can lead to severe pain and discomfort. This report describes a case of a 31-year-old patient with acromegaly induced bilateral condylar hyperplasia who presented with severe temporomandibular joint (TMJ), facial pain, and degenerative changes in TMJ. The patient was treated by trans-sphenoidal excision of pituitary adenoma, medications, and radiotherapy, but his hormonal levels were persistently high. Considering the refractory nature of the disease, the patient underwent bilateral high condylectomy, right articular disc removal, and abdominal dermis fat grafting. The surgery arrested the progressive mandibular enlargement and prevented further degenerative changes of TMJ. Although there was some reduction in TMJ pain, the myogenous pain and headache persisted after surgery. TMJ surgery may be selectively used for refractory cases of acromegaly and those requiring discectomy or total joint replacement. This case report describes the role of TMJ surgery in the management of morbidities and symptoms associated with TMJ in acromegaly until biochemical normalcy is achieved.

Comparison of Transconjunctival versus Subtarsal Approach in Orbital Reconstruction with Respect to Post-Operative Complications and Aesthetic Outcome - A Systematic Review.

Background: Limited evidence exists regarding the optimal surgical approach for orbital floor reconstruction, resulting in uncertainty regarding the choice of approach with the best aesthetic outcomes and lowest post-operative complications. Objectives: This systematic review aimed to compare the transconjunctival and subtarsal approaches (STA) in orbital reconstruction in terms of post-operative complications and aesthetic outcomes. Data Sources: The systematic review was conducted following PRISMA guidelines. PubMed, Google Scholar and Cochrane databases were searched from January 1, 2000 and December 31, 2021. Study Eligibility Criteria: Eligible studies included clinical studies comparing the transconjunctival and STA approaches in orbital reconstruction. The outcome variables assessed were aesthetic scar, hyperaesthesia, entropion, ectropion, enophthalmos, epiphora and other complications. A total of 346 articles were initially identified, and after evaluation using Mendeley software, 292 articles were reviewed. Finally, five articles that met the inclusion criteria were included in this systematic review. Study Appraisal and Results: The transconjunctival approach demonstrated superior aesthetic outcomes compared to the STA approach. However, the STA approach had a lower incidence of post-operative complications, including hyperaesthesia, entropion, ectropion, enophthalmos and epiphora. Limitations: The main limitation of this systematic review is the limited availability of literature directly comparing these two approaches, which precluded the inclusion of randomised controlled trials. Furthermore, the search strategy was restricted to specific databases, namely PubMed/Medline, Google Scholar and the Cochrane Collaboration Library.

Effectiveness of Dermis Fat Graft Versus Temporalis Myofascial Flap for Interposition in Temporomandibular Joint Ankylosis: A Systematic Review.

Background: Temporomandibular joint ankylosis is a disabling condition which affects joint movements causing difficulty in speech, mastication and hygiene. Over time various interposition materials like meniscus, muscle, fascia, skin, cartilage, fat, dura and alloplastic materials have been used for the treatment of ankylosis and improve joint functions. Objective: The objective of this systematic review is to evaluate the effectiveness of dermis fat graft and temporalis myofascial flap as an interpositional material in treatment of temporomandibular joint ankylosis and to compare the effectiveness of the two materials. Materials and Methods: PubMed, Google scholar, and Cochrane library search in combination with hand search of relevant journals were conducted published in English from January 2000 to August 2021. Randomized controlled trials, prospective and retrospective cohort studies were included. Outcome measure included improvement in mouth opening. Risk of bias assessment was assessed using Cochrane risk of bias tool and Newcastle-Ottawa scale. Results: A total of 144 articles were found from the primary search which on thorough assessment, duplicate and exclusion removal resulted in 9 cohort studies and 1 randomized controlled trial that fulfilled the inclusion criteria. All the studies included reported significant improvement in mouth opening after interposition of the 2 materials. Four studies compared temporalis myofascial flap with dermis fat graft, 2 studies reported dermis fat graft gives better outcomes, whereas 1 study reported temporalis myofascial flap to be better and 1 study has been inconclusive. Conclusion: Definitive conclusions cannot be drawn as there are number of limitations in the studies included. However a general consensus has been toward dermis fat graft owing to fewer complications. Supplementary Information: The online version contains supplementary material available at 10.1007/s12663-023-01869-9.

Study of Telerobot Personalization for Children: Exploring Qualitative Coding of Artwork.

Social telepresence robots (i.e., telerobots) are used for social and learning experiences by children. However, most (if not all) commercially available telerobot bodies were designed for adults in corporate or healthcare settings. Due to an adult-focused market, telerobot design has typically not considered important factors such as age and physical aspect in the design of robot bodies. To better understand how peer interactants can facilitate the identities of remote children through personalization of robot bodies, we conducted an exploratory study to evaluate collaborative robot personalization. In this study, child participants (N=28) attended an interactive lesson on robots in our society. After the lesson, participants interacted with two telerobots for personalization activities and a robot fashion show. Finally, participants completed an artwork activity on robot design. Initial findings from this study will inform our continued work on telepresence robots for virtual inclusion and improved educational experiences of remote children and their peers.

Clinical efficacy of 0.75% ropivacaine vs. 2% lignocaine hydrochloride with adrenaline (1:80,000) in patients undergoing removal of bilateral maxillary third molars: a randomized controlled trial.

BACKGROUND: Lignocaine with adrenaline is routinely used as a local anesthetic for dental procedures. Adrenaline was added to increase the duration of anesthesia. However, epinephrine containing a local anesthetic solution is not recommended in conditions such as advanced cardiovascular diseases and hyperthyroidism. Recently, ropivacaine has gained popularity as a long-acting anesthetic with superior outcomes. The goal of this study was to assess and compare the effectiveness of 0.75% ropivacaine alone and 2% lignocaine with adrenaline (1:80,000) in the removal of bilateral maxillary wisdom teeth using the posterior superior alveolar nerve block technique. METHODS: This was a single-blind, randomized, split-mouth, prospective study assessing 15 systemically sound outpatients who needed bilateral removal of maxillary third molars. We randomly allocated the sides and sequences of ropivacaine and lignocaine with adrenaline administration. We evaluated the efficacy of both anesthetics with regard to the onset of anesthesia, intensity of pain, variation in heart rate, and blood pressure. RESULTS: The onset of anesthesia was faster with lignocaine (138 s) than with ropivacaine (168 s), with insignificant differences (p = 0.001). There was no need for additional local anesthetics in the ropivacaine group, while in the lignocaine with adrenaline group, 2 (13.3%) patients required additional anesthesia. Adequate intraoperative anesthesia was provided by ropivacaine and lignocaine solutions. No significant difference was observed in the perioperative variation in blood pressure and heart rate. CONCLUSION: Ropivacaine (0.75%) is a safe and an adrenaline-free local anesthetic option for posterior superior alveolar nerve block, which provides adequate intraoperative anesthesia and a stable hemodynamic profile for the removal of the maxillary third molar.

To evaluate the Efficacy of Buprenorphine and 2% lignocaine with adrenaline as postoperative analgesia following mandibular third molar surgery: A Comparative Study.

Introduction: Opioid analgesics have an advantage over nonsteroidal anti-inflammatory drugs in that they do not cause direct organ damage. Buprenorphine has an antinociceptive potency approximately 25-50 times greater than that of morphine. Hence, in this study, buprenorphine was added to local anaesthesia in relieving postoperative pain after lower third molar surgery when given as inferior alveolar nerve block. The aim of this study was to evaluate the efficacy of buprenorphine in managing postoperative pain after lower third molar surgery. Materials and Methods: Fifty patients requiring lower third molar surgery were randomly divided into two groups. Group A received buprenorphine added to 2% lignocaine with 1:80,000 adrenaline and Group B received 2% lignocaine with 1:80,000 adrenaline. Parameters assessed were onset of anaesthesia, depth of anaesthesia, intraoperative monitoring of adverse effects, duration of analgesia, and number of analgesics consumed. Statistical analysis was carried out using SPSS software version 21. The data were compared using Student's t-test. The level of significance was set at 0.05. Results: There was a significant difference in onset of anaesthesia between Group A and Group B (P < 0.05). Depth of anaesthesia and duration of analgesia were greater in Group A (56 h 36 min) than Group B (3 h 24 min). Analgesics consumed by Group A (0.9) were significantly less compared to Group B (9.2) and it was highly significant (P = 0.000). Discussion: Buprenorphine when added to local anaesthesia can prolong postoperative analgesia with minimum or no side effects. Hence, buprenorphine can be safely used for lower third molar surgery.

Towards mobile gaze-directed beamforming: a novel neuro-technology for hearing loss.

Contemporary hearing aids are markedlylimited in their most important role: improving speech perception in dynamic "cocktail party" environments with multiple, competing talkers. Here we describe an open-source, mobile assistive hearing platform entitled "Cochlearity" which uses eye gaze to guide an acoustic beamformer, so a listener will hear best wherever they look. Cochlearity runs on Android and its eight-channel microphone array can be worn comfortably on the head, e.g. mounted on eyeglasses. In this preliminary report, we examine the efficacy of both a static (delay-and-sum) and an adaptive (MVDR) beamformer in the task of separating an "attended" voice from an "unattended" voice in a two-talker scenario. We show that the different beamformers have the potential to complement each other to improve target speech SNR (signal to noise ratio), across the range of speech power, with tolerably low latency.

Upper Limb Prosthesis Control for High-Level Amputees via Myoelectric Recognition of Leg Gestures.

Recognition of motion intent via surface electromyography (EMG) has become increasingly practical for prosthesis control, but lacking residual muscle sites remains a major obstacle to its use by high-level amputees. Currently, there are few approaches to upper limb prosthesis control for individuals with amputations proximal to the elbow, all of which suffer from one or more of three primary problems: invasiveness, the need for intensive training, and lacking functionality. Using surface EMG sensors placed on the lower leg and a natural mapping between degrees of freedom of the leg and the arm, we tested a noninvasive control approach by which high-level amputees could control prosthetic elbow, wrist, and hand movements with minimal training. In this paper, we used able-bodied subjects to facilitate a direct comparison between control using intact arm and leg muscles. First, we found that foot gestures could be classified offline using time domain features and linear discriminant analysis with accuracy comparable to an equivalent system for recognizing arm movements. Second, we used the target achievement control test to evaluate real-time control performance in three and four degrees of freedom. After approximately 20 min of training, subjects tended to perform the task as well with the leg as with intact arm muscles, and performance overall was comparable to other control methods.

Effects of muscle fatigue on the usability of a myoelectric human-computer interface.

Electromyography-based human-computer interface development is an active field of research. However, knowledge on the effects of muscle fatigue for specific devices is limited. We have developed a novel myoelectric human-computer interface in which subjects continuously navigate a cursor to targets by manipulating a single surface electromyography (sEMG) signal. Two-dimensional control is achieved through simultaneous adjustments of power in two frequency bands through a series of dynamic low-level muscle contractions. Here, we investigate the potential effects of muscle fatigue during the use of our interface. In the first session, eight subjects completed 300 cursor-to-target trials without breaks; four using a wrist muscle and four using a head muscle. The wrist subjects returned for a second session in which a static fatiguing exercise took place at regular intervals in-between cursor-to-target trials. In the first session we observed no declines in performance as a function of use, even after the long period of use. In the second session, we observed clear changes in cursor trajectories, paired with a target-specific decrease in hit rates.

Learning to modulate the partial powers of a single sEMG power spectrum through a novel human-computer interface.

New human-computer interfaces that use bioelectrical signals as input are allowing study of the flexibility of the human neuromuscular system. We have developed a myoelectric human-computer interface which enables users to navigate a cursor to targets through manipulations of partial powers within a single surface electromyography (sEMG) signal. Users obtain two-dimensional control through simultaneous adjustments of powers in two frequency bands within the sEMG spectrum, creating power profiles corresponding to cursor positions. It is unlikely that these types of bioelectrical manipulations are required during routine muscle contractions. Here, we formally establish the neuromuscular ability to voluntarily modulate single-site sEMG power profiles in a group of naïve subjects under restricted and controlled conditions using a wrist muscle. All subjects used the same pre-selected frequency bands for control and underwent the same training, allowing a description of the average learning progress throughout eight sessions. We show that subjects steadily increased target hit rates from 48% to 71% and exhibited greater control of the cursor's trajectories following practice. Our results point towards an adaptable neuromuscular skill, which may allow humans to utilize single muscle sites as limited general-purpose signal generators. Ultimately, the goal is to translate this neuromuscular ability to practical interfaces for the disabled by using a spared muscle to control external machines.

Real-time evaluation of a myoelectric control method for high-level upper limb amputees based on homologous leg movements.

Electromyography-based gesture classification methods for control of advanced upper limb prostheses are limited either to individuals with amputations distal to the elbow or to those willing to undergo targeted muscle reinnervation surgery. Based on the natural similarity between gestures of the lower leg and the arm and on established methods in electromyography-based gesture classification, we propose a noninvasive system with which users control an upper limb prosthesis via homologous movements of the leg and foot. Eight inexperienced able-bodied subjects controlled a simulated robotic arm in a target achievement control (TAC) task with command of up to four degrees of freedom toward targets requiring one motion class. All subjects performed the task with analogous electromyography recording configurations on both the leg and the arm (as a benchmark), achieving slightly better performance with leg control overall. Only a brief demonstration of the arm-leg gesture mapping was necessary for subjects to perform the task, establishing the minimal training time required to begin using the control scheme. Our findings indicate that electromyography-based recognition of leg gestures may be a viable noninvasive prosthesis control option for high-level amputees.

Paralyzed subject controls telepresence mobile robot using novel sEMG brain-computer interface: case study.

Here we demonstrate the use of a new singlesignal surface electromyography (sEMG) brain-computer interface (BCI) to control a mobile robot in a remote location. Previous work on this BCI has shown that users are able to perform cursor-to-target tasks in two-dimensional space using only a single sEMG signal by continuously modulating the signal power in two frequency bands. Using the cursor-to-target paradigm, targets are shown on the screen of a tablet computer so that the user can select them, commanding the robot to move in different directions for a fixed distance/angle. A Wifi-enabled camera transmits video from the robot's perspective, giving the user feedback about robot motion. Current results show a case study with a C3-C4 spinal cord injury (SCI) subject using a single auricularis posterior muscle site to navigate a simple obstacle course. Performance metrics for operation of the BCI as well as completion of the telerobotic command task are developed. It is anticipated that this noninvasive and mobile system will open communication opportunities for the severely paralyzed, possibly using only a single sensor.

Pilot study for a Brain-Muscle-Computer Interface using the Extensor Pollicis Longus with preselected frequency bands.

We are developing a new class of Brain-Computer Interface that we call a Brain-Muscle-Computer Interface, in which surface electromyography (sEMG) recordings from a single muscle site are used to control the movement of a cursor. Previous work in our laboratory has established that subjects can learn to navigate a cursor to targets by manipulating the sEMG from a head muscle (the Auricularis Superior). Subjects achieved two-dimensional control of the cursor by simultaneously regulating the power in two frequency bands that were chosen to suit the individuals. The purposes of the current pilot study were to investigate (i) subjects' abilities to manipulate power in separate frequency bands in other muscles of the body and (ii) whether subjects can adapt to preselected frequency bands. We report pilot study data suggesting that subjects can learn to perform cursor-to-target tasks on a mobile phone by contracting the Extensor Pollicis Longus (a muscle located on the wrist) using frequency bands that are the same for every individual. After the completion of a short training protocol of less than 30 minutes, three subjects achieved 83%, 60% and 60% accuracies (with mean time-to-targets of 3.4 s, 1.4 s and 2.7 s respectively). All three subjects improved their performance, and two subjects decreased their time-to-targets following training. These results suggest that subjects may be able to use the Extensor Pollicis Longus to control the BMCI and adapt to preselected frequency bands. Further testing will more conclusively investigate these preliminary findings.

Brain-muscle-computer interface: mobile-phone prototype development and testing.

We report prototype development and testing of a new mobile-phone-based brain-muscle-computer interface for severely paralyzed persons, based on previous results from our group showing that humans may actively create specified power levels in two separate frequency bands of a single surface electromyography (sEMG) signal. EMG activity on the surface of a single face muscle site (auricularis superior) is recorded with a standard electrode. This analog electrical signal is imported into an Android-based mobile phone and digitized via an internal A/D converter. The digital signal is split, and then simultaneously filtered with two band-pass filters to extract total power within two separate frequency bands. The user-modulated power in each frequency band serves as two separate control channels for machine control. After signal processing, the Android phone sends commands to external devices via a Bluetooth interface. Users are trained to use the device via visually based operant conditioning, with simple cursor-to-target activities on the phone screen. The mobile-phone prototype interface is formally evaluated on a single advanced Spinal Muscle Atrophy subject, who has successfully used the interface in his home in evaluation trials and for remote control of a television. Development of this new device will not only guide future interface design for community use, but will also serve as an information technology bridge for in situ data collection to quantify human sEMG manipulation abilities for a relevant population.

Multidimensional control using a mobile-phone based brain-muscle-computer interface.

Many well-known brain-computer interfaces measure signals at the brain, and then rely on the brain's ability to learn via operant conditioning in order to control objects in the environment. In our lab, we have been developing brain-muscle-computer interfaces, which measure signals at a single muscle and then rely on the brain's ability to learn neuromuscular skills via operant conditioning. Here, we report a new mobile-phone based brain-muscle-computer interface prototype for severely paralyzed persons, based on previous results from our group showing that humans may actively create specified power levels in two separate frequency bands of a single sEMG signal. Electromyographic activity on the surface of a single face muscle (Auricularis superior) is recorded with a standard electrode. This analog electrical signal is imported into an Android-based mobile phone. User-modulated power in two separate frequency band serves as two separate and simultaneous control channels for machine control. After signal processing, the Android phone sends commands to external devices via Bluetooth. Users are trained to use the device via biofeedback, with simple cursor-to-target activities on the phone screen.

Two-dimensional cursor-to-target control from single muscle site sEMG signals.

In this study, human subjects achieve two-dimensional cursor-to-target control using the surface electromyogram (sEMG) from a single muscle site. The X-coordinate and the Y-coordinate of the computer cursor were simultaneously controlled by the active manipulation of power within two frequency bands of the sEMG power-spectrum. Success of the method depends on the sEMG frequency bandwidths and their midpoints. We acquired the sEMG signals at a single facial muscle site of four able-bodied subjects and trained them, by visual feedback, to control the position of the cursor. After training, all four subjects were able to simultaneously control the X and Y positions of the cursor to accurately and consistently hit three widely-separated targets on a computer screen. This technology has potential application in a wide variety of human-machine interfaces to assistive technologies.

Ground squirrels use an infrared signal to deter rattlesnake predation.

The evolution of communicative signals involves a major hurdle; signals need to effectively stimulate the sensory systems of their targets. Therefore, sensory specializations of target animals are important sources of selection on signal structure. Here we report the discovery of an animal signal that uses a previously unknown communicative modality, infrared radiation or "radiant heat," which capitalizes on the infrared sensory capabilities of the signal's target. California ground squirrels (Spermophilus beecheyi) add an infrared component to their snake-directed tail-flagging signals when confronting infrared-sensitive rattlesnakes (Crotalus oreganus), but tail flag without augmenting infrared emission when confronting infrared-insensitive gopher snakes (Pituophis melanoleucus). Experimental playbacks with a biorobotic squirrel model reveal this signal's communicative function. When the infrared component was added to the tail flagging display of the robotic models, rattlesnakes exhibited a greater shift from predatory to defensive behavior than during control trials in which tail flagging included no infrared component. These findings provide exceptionally strong support for the hypothesis that the sensory systems of signal targets should, in general, channel the evolution of signal structure. Furthermore, the discovery of previously undescribed signaling modalities such as infrared radiation should encourage us to overcome our own human-centered sensory biases and more fully examine the form and diversity of signals in the repertoires of many animal species.

The control of a parallel hybrid-electric propulsion system for a small unmanned aerial vehicle using a CMAC neural network.

A Simulink model, a propulsion energy optimization algorithm, and a CMAC controller were developed for a small parallel hybrid-electric unmanned aerial vehicle (UAV). The hybrid-electric UAV is intended for military, homeland security, and disaster-monitoring missions involving intelligence, surveillance, and reconnaissance (ISR). The Simulink model is a forward-facing simulation program used to test different control strategies. The flexible energy optimization algorithm for the propulsion system allows relative importance to be assigned between the use of gasoline, electricity, and recharging. A cerebellar model arithmetic computer (CMAC) neural network approximates the energy optimization results and is used to control the parallel hybrid-electric propulsion system. The hybrid-electric UAV with the CMAC controller uses 67.3% less energy than a two-stroke gasoline-powered UAV during a 1-h ISR mission and 37.8% less energy during a longer 3-h ISR mission.