Statistical evaluation of tongue capability with visual feedback.

BACKGROUND: Analysis of tongue movement would benefit from a reference showcasing healthy tongue capability. We aimed to develop a reference of tongue capability and evaluated the role of visual feedback on the expression of movement. METHODS: Using a wireless tracking intraoral wearable device, we composed probability distributions of the tongue tip as subjects were asked to explore the entire sensing surface area. Half of the 32 subjects received live visual feedback of the location of the center of the tongue tip contact. RESULTS: We observed that the visual feedback group was 51.0% more consistent with each other in the position domain, explored 21.5% more sensing surface area, and was 50.7% more uniformly distributed. We found less consistent results when we evaluated velocity and acceleration. CONCLUSION: Visual feedback best established a healthy capability reference which can be used for designing new interfaces, quantifying tongue ability, developing new diagnostic and rehabilitation techniques, and studying underlying mechanisms of tongue motor control.

Movement of the Tongue During Target Reaching on a 2-Dimensional Surface.

The tongue's physiological complexity and hidden location inside the oral cavity, limit our ability to quantify its fast and dynamic motions. Our team has developed a discreet wireless intraoral wearable device to study the tongue motion. In this paper, tongue movements were analyzed during functional tasks of target reaching when controlling a cursor on a computer screen. Ten healthy individuals participated in this study. Movement trajectories were compared to straight lines using the maximum perpendicular distance error. Results suggest that the tongue directs the cursor closer to a straight line when moving along the anteroposterior and mediolateral direction. We also observed that with practice the movement error along the mediolateral axis decreases more than the error for the anteroposterior and angular movements.

The Pattern of Tongue's Motion: A Free-Exploration Study.

The human tongue is involved in many essential daily activities and is comprised of eight muscles. To date tools for quantifications of the tongue's intrinsic motions are limited. In this study we explored the tongue's motion during a free-exploration paradigm, using a discreet wireless intra-oral wearable device. Six healthy subjects were instructed to freely move the tip of their tongue on the wearable device while attempting to cover the entire surface of the hard palate. The goal of this study is to compose a two-dimensional probability distribution model of the tongue's motion. We conclude that 90-seconds of non-continuous data collection was sufficient for visualizing the two-dimensional probability distribution of the free-exploration paradigm. The results suggest that the subjects concentrate the majority of the motion in the central portion of the palate.

GLOS: GLOve for Speech Recognition.

Technological advancements in the field of Biomedical Engineering have allowed impaired individuals to use assistive devices in order to improve their quality of life. In the case of deafblind subjects, who experience both visual and auditory loss, the majority of available assistive devices are invasive (e.g. cochlear implants). Non-invasive technological improvements are extremely limited, in part due to the lack of scientific research interest in dual sensory loss [1]. In this paper we aim to present GLOS, a low-cost and non-invasive device that will allow the deafblind individuals to comprehend speeches in real-time. The proposed wearable device uses off-the-shelf components such as a Raspberry Pi 3 board, a simple microphone, and haptic feedback vibrating disks. The recorded speech from the microphone is processed by the board and encoded into 5 haptic vibrating modules attached to a glove. Each haptic vibrating module is placed on a different finger of the right hand. The current available non-invasive solutions do not use speech and therefore they do not allow for live communication (e.g. MyVox [2], Sparsha [3] and Mobile Lorm Glove [4]) or require long procedures to convert the messages (e.g. Finger Braille Teaching System [5]). This new biomedical device aims at overcoming these limitations. The authors tested the device in a preliminary testing and it was shown that GLOS has an average accuracy of 91.67% when tested for the recognition of twenty encoded sentences. The authors were deprived of both visual and hearing inputs and were trained for half hour per day for a period of 30 days.

Emotion Recognition for Brain Machine Interface: Non-linear Spectral Analysis of EEG Signals Using Empirical Mode Decomposition.

Emotions are a fundamental part of the human experience but currently there are no methods that can objectively detect and categorize them. This study utilizes the empirical mode decomposition (EMD) method to categorize emotions from encephalography (EEG) recordings. In the past, EMD has proven to be a very useful signal analysis tool because of its ability to decompose nonstationary signals, like those from an EEG, into component signals with varying frequency content called intrinsic mode functions (IMFs). The method in this paper utilizes three features extracted from the IMFs-the first difference of time, the first difference of phase, and the normalized energy-for data categorization using support vector machine (SVM) classifiers. Two classifiers were trained for each subject, one for valence and another for arousal. The mean accuracies yielded for valence and arousal were 75.86% and 75.31%, respectively. The results of this study verify previous findings by other researchers that these three features are useful in emotion recognition when applied to previously recorded EEG data, though we add the caveat that subject-specific classifiers are needed instead of generalized, global classifiers.

TongueToSpeech (TTS): Wearable wireless assistive device for augmented speech.

Speech is an important aspect of human communication; individuals with speech impairment are unable to communicate vocally in real time. Our team has developed the TongueToSpeech (TTS) device with the goal of augmenting speech communication for the vocally impaired. The proposed device is a wearable wireless assistive device that incorporates a capacitive touch keyboard interface embedded inside a discrete retainer. This device connects to a computer, tablet or a smartphone via Bluetooth connection. The developed TTS application converts text typed by the tongue into audible speech. Our studies have concluded that an 8-contact point configuration between the tongue and the TTS device would yield the best user precision and speed performance. On average using the TTS device inside the oral cavity takes 2.5 times longer than the pointer finger using a T9 (Text on 9 keys) keyboard configuration to type the same phrase. In conclusion, we have developed a discrete noninvasive wearable device that allows the vocally impaired individuals to communicate in real time.

Wearable wireless User Interface Cursor-Controller (UIC-C).

Controlling a computer or a smartphone's cursor allows the user to access a world full of information. For millions of people with limited upper extremities motor function, controlling the cursor becomes profoundly difficult. Our team has developed the User Interface Cursor-Controller (UIC-C) to assist the impaired individuals in regaining control over the cursor. The UIC-C is a hands-free device that utilizes the tongue muscle to control the cursor movements. The entire device is housed inside a subject specific retainer. The user maneuvers the cursor by manipulating a joystick imbedded inside the retainer via their tongue. The joystick movement commands are sent to an electronic device via a Bluetooth connection. The device is readily recognizable as a cursor controller by any Bluetooth enabled electronic device. The device testing results have shown that the time it takes the user to control the cursor accurately via the UIC-C is about three times longer than a standard computer mouse controlled via the hand. The device does not require any permanent modifications to the body; therefore, it could be used during the period of acute rehabilitation of the hands. With the development of modern smart homes, and enhancement electronics controlled by the computer, UIC-C could be integrated into a system that enables individuals with permanent impairment, the ability to control the cursor. In conclusion, the UIC-C device is designed with the goal of allowing the user to accurately control a cursor during the periods of either acute or permanent upper extremities impairment.

A novel obstetric medical device designed for autotransfusion of blood in life threatening postpartum haemorrhage.

Postpartum haemorrhage (PPH) is an obstetric emergency caused by excessive blood loss after delivery, which is the leading cause of maternal mortality worldwide. PPH can lead to volume depletion, hypovolemic shock, anaemia and ultimately death. The prevalence of PPH is disproportionately higher in low resource settings where there is limited access to skilled medical care and safe blood supplies. Current management strategies target both prevention and treatment of PPH however no alternatives currently exist to address the lack of safe blood supplies which are considered essential in emergency obstetrical care. Autotransfusion is used to salvage blood loss in a variety of clinical settings but has never been used in the context of vaginal delivery. We describe the development and testing of a novel device for the collection, filtration and autotransfusion of blood lost due to PPH. The prototype device is inexpensive and easily operated so that it may be practically deployed in low resource settings. The device is comprised of a blood collection drape, a pump apparatus, three leukocyte reduction filters and a reservoir for filtered blood. Preliminary testing demonstrates efficacy of microbial load reduction of up to 97.3%. To reduce cost and improve safety, the device is modular in design such that the drape, tubing, filters and transfusion bag may be stored sterile, used once and discarded; while the pump apparatus may be used indefinitely without the need for sterilisation. Preliminary results indicate the device confers a low cost and potentially effective means of collecting, pumping, filtering and returning blood to a patient following PPH in settings that lack safe blood supplies. This device shows promise as a method of stabilising patients suffering of PPH in low resource settings until definitive treatment is rendered with the ultimate goal of reducing maternal mortality globally.