Augmenting perceived stickiness of physical objects through tactile feedback after finger lift-off.

Haptic Augmented Reality (HAR) is a method that actively modulates the perceived haptics of physical objects by presenting additional haptic feedback using a haptic display. However, most of the proposed HAR research focuses on modifying the hardness, softness, roughness, smoothness, friction, and surface shape of physical objects. In this paper, we propose an approach to augment the perceived stickiness of a physical object by presenting additional tactile feedback at a particular time after the finger lifts off from the physical object using a thin and soft tactile display suitable for HAR. To demonstrate this concept, we constructed a thin and soft tactile display using a Dielectric Elastomer Actuator suitable for HAR. We then conducted two experiments to validate the effectiveness of the proposed approach. In Experiment 1, we showed that the developed tactile display can augment the perceived stickiness of physical objects by presenting additional tactile feedback at appropriate times. In Experiment 2, we investigated the stickiness experience obtained by our proposed approach and showed that the realism of the stickiness experience and the harmony between the physical object and the additional tactile feedback are affected by the frequency and presentation timing of the tactile feedback. Our proposed approach is expected to contribute to the development of new applications not only in HAR, but also in Virtual Reality, Mixed Reality, and other domains using haptic displays.

Neural substrate for the engagement of the ventral visual stream in motor control in the macaque monkey.

The present study aimed to describe the cortical connectivity of a sector located in the ventral bank of the superior temporal sulcus in the macaque (intermediate area TEa and TEm [TEa/m]), which appears to represent the major source of output of the ventral visual stream outside the temporal lobe. The retrograde tracer wheat germ agglutinin was injected in the intermediate TEa/m in four macaque monkeys. The results showed that 58-78% of labeled cells were located within ventral visual stream areas other than the TE complex. Outside the ventral visual stream, there were connections with the memory-related medial temporal area 36 and the parahippocampal cortex, orbitofrontal areas involved in encoding subjective values of stimuli for action selection, and eye- or hand-movement related parietal (LIP, AIP, and SII), prefrontal (12r, 45A, and 45B) areas, and a hand-related dysgranular insula field. Altogether these data provide a solid substrate for the engagement of the ventral visual stream in large scale cortical networks for skeletomotor or oculomotor control. Accordingly, the role of the ventral visual stream could go beyond pure perceptual processes and could be also finalized to the neural mechanisms underlying the control of voluntary motor behavior.

Evaluation of forces applied to tissues during robotic-assisted surgical tasks using a novel force feedback technology.

BACKGROUND: The absence of force feedback (FFB) is considered a technical limitation in robotic-assisted surgery (RAS). This pre-clinical study aims to evaluate the forces applied to tissues using a novel integrated FFB technology, which allows surgeons to sense forces exerted at the instrument tips. METHODS: Twenty-eight surgeons with varying experience levels employed FFB instruments to perform three robotic-assisted surgical tasks, including retraction, dissection, and suturing, on inanimate or ex-vivo models, while the instrument sensors recorded and conveyed the applied forces to the surgeon hand controllers of the robotic system. Generalized Estimating Equations (GEE) models were used to analyze the mean and maximal forces applied during each task with the FFB sensor at the "Off" setting compared to the "High" sensitivity setting for retraction and to the "Low", "Medium", and "High" sensitivity settings for dissection and suturing. Sub-analysis was also performed on surgeon experience levels. RESULTS: The use of FFB at any of the sensitivity settings resulted in a significant reduction in both the mean and maximal forces exerted on tissue during all three robotic-assisted surgical tasks (p < 0.0001). The maximal force exerted, potentially associated with tissue damage, was decreased by 36%, 41%, and 55% with the use of FFB at the "High" sensitivity setting while performing retraction, dissection, and interrupted suturing tasks, respectively. Further, the use of FFB resulted in substantial reductions in force variance during the performance of all three types of tasks. In general, reductions in mean and maximal forces were observed among surgeons at all experience levels. The degree of force reduction depends on the sensitivity setting selected and the types of surgical tasks evaluated. CONCLUSIONS: Our findings demonstrate that the utilization of FFB technology integrated in the robotic surgical system significantly reduced the forces exerted on tissue during the performance of surgical tasks at all surgeon experience levels. The reduction in the force applied and a consistency of force application achieved with FFB use, could result in decreases in tissue trauma and blood loss, potentially leading to better clinical outcomes in patients undergoing RAS. Future studies will be important to determine the impact of FFB instruments in a live clinical environment.

Artificial intelligence: revolutionizing robotic surgery: review.

Robotic surgery, known for its minimally invasive techniques and computer-controlled robotic arms, has revolutionized modern medicine by providing improved dexterity, visualization, and tremor reduction compared to traditional methods. The integration of artificial intelligence (AI) into robotic surgery has further advanced surgical precision, efficiency, and accessibility. This paper examines the current landscape of AI-driven robotic surgical systems, detailing their benefits, limitations, and future prospects. Initially, AI applications in robotic surgery focused on automating tasks like suturing and tissue dissection to enhance consistency and reduce surgeon workload. Present AI-driven systems incorporate functionalities such as image recognition, motion control, and haptic feedback, allowing real-time analysis of surgical field images and optimizing instrument movements for surgeons. The advantages of AI integration include enhanced precision, reduced surgeon fatigue, and improved safety. However, challenges such as high development costs, reliance on data quality, and ethical concerns about autonomy and liability hinder widespread adoption. Regulatory hurdles and workflow integration also present obstacles. Future directions for AI integration in robotic surgery include enhancing autonomy, personalizing surgical approaches, and refining surgical training through AI-powered simulations and virtual reality. Overall, AI integration holds promise for advancing surgical care, with potential benefits including improved patient outcomes and increased access to specialized expertise. Addressing challenges and promoting responsible adoption are essential for realizing the full potential of AI-driven robotic surgery.

Enhancing stroke rehabilitation with whole-hand haptic rendering: development and clinical usability evaluation of a novel upper-limb rehabilitation device.

INTRODUCTION: There is currently a lack of easy-to-use and effective robotic devices for upper-limb rehabilitation after stroke. Importantly, most current systems lack the provision of somatosensory information that is congruent with the virtual training task. This paper introduces a novel haptic robotic system designed for upper-limb rehabilitation, focusing on enhancing sensorimotor rehabilitation through comprehensive haptic rendering. METHODS: We developed a novel haptic rehabilitation device with a unique combination of degrees of freedom that allows the virtual training of functional reach and grasp tasks, where we use a physics engine-based haptic rendering method to render whole-hand interactions between the patients' hands and virtual tangible objects. To evaluate the feasibility of our system, we performed a clinical mixed-method usability study with seven patients and seven therapists working in neurorehabilitation. We employed standardized questionnaires to gather quantitative data and performed semi-structured interviews with all participants to gain qualitative insights into the perceived usability and usefulness of our technological solution. RESULTS: The device demonstrated ease of use and adaptability to various hand sizes without extensive setup. Therapists and patients reported high satisfaction levels, with the system facilitating engaging and meaningful rehabilitation exercises. Participants provided notably positive feedback, particularly emphasizing the system's available degrees of freedom and its haptic rendering capabilities. Therapists expressed confidence in the transferability of sensorimotor skills learned with our system to activities of daily living, although further investigation is needed to confirm this. CONCLUSION: The novel haptic robotic system effectively supports upper-limb rehabilitation post-stroke, offering high-fidelity haptic feedback and engaging training tasks. Its clinical usability, combined with positive feedback from both therapists and patients, underscores its potential to enhance robotic neurorehabilitation.

Virtual Needle Insertion with Enhanced Haptic Feedback for Guidance and Needle-Tissue Interaction Forces.

Interventional radiologists mainly rely on visual feedback via imaging modalities to steer a needle toward a tumor during biopsy and ablation procedures. In the case of CT-guided procedures, there is a risk of exposure to hazardous X-ray-based ionizing radiation. Therefore, CT scans are usually not used continuously, which increases the chances of a misplacement of the needle and the need for reinsertion, leading to more tissue trauma. Interventionalists also encounter haptic feedback via needle-tissue interaction forces while steering a needle. These forces are useful but insufficient to clearly perceive and identify deep-tissue structures such as tumors. The objective of this paper was to investigate the effect of enhanced force feedback for sensing interaction forces and guiding the needle when applied individually and simultaneously during a virtual CT-guided needle insertion task. We also compared the enhanced haptic feedback to enhanced visual feedback. We hypothesized that enhancing the haptic feedback limits the time needed to reach the target accurately and reduces the number of CT scans, as the interventionalist depends more on real-time enhanced haptic feedback. To test the hypothesis, a simulation environment was developed to virtually steer a needle in five degrees of freedom (DoF) to reach a tumor target embedded in a liver model. Twelve participants performed in the experiment with different feedback conditions where we measured their performance in terms of the following: targeting accuracy, trajectory tracking, number of CT scans required, and the time needed to finish the task. The results suggest that the combination of enhanced haptic feedback for guidance and sensing needle-tissue interaction forces significantly reduce the number of scans and the duration required to finish the task by 32.1% and 46.9%, respectively, when compared to nonenhanced haptic feedback. The other feedback modalities significantly reduced the duration to finish the task by around 30% compared to nonenhanced haptic feedback.

Creative puppet therapy reduces hallucinations in patients diagnosed with schizophrenia: Preliminary findings.

Anomalous experiences and hallucinations characterize schizophrenia. This study aimed at determining the efficacy of creative puppet therapy (CPT; creation of a puppet with malleable DAS) to reduce severe anomalous experiences and hallucinations among patients diagnosed with schizophrenia. Double-blinded, controlled trials were performed on a convenience sample of 24 patients from a mental health center. The intervention group of 12 patients (who created puppets) and the pseudo-treatment group of 12 patients (who were involved in outdoor leisure trips) were compared to the control group of 12 control participants (who created puppets). Cardiff Anomalous Perceptions Scale (CAPS) assessed hallucinations; Emotional Expression Inventory (EEXI) assessed the emotional expression of one's own puppet. Puppet facial features were measured. Results showed that CPT effectively reduced (d = -4.00) hallucination frequency in patients. Hallucination reduction occurred across all sensory modalities, but touch and bodily interoception. Exteroceptive vs. interoceptive hallucinations was the most valuable classification in patients. Compared to controls, puppets created by patients expressed more negative emotions and had larger eye diameters, shorter noses, and larger whole face width. Eye diameter was correlated with fear, sadness, anger, and disgust, and whole face width with boredom. Fragmented-self integration of schizophrenia through CPT treatment might exploit aggregative dominance of the patient's own body.

Effectiveness of anti-psychiatric treatment on visual and haptic perceptual disorder for a patient with Alzheimer's disease: A case report.

BACKGROUND: Perception is frequently impaired in patients with Alzheimer's disease (AD). Several patients exhibit visual or haptic hallucinations. CASE SUMMARY: A 71-year-old Chinese man presented with visual and haptic hallucinations he had been experiencing for 2 weeks. The clinical manifestations were the feeling of insects crawling and biting the limbs and geison. He looked for the insects while itching and scratching, which led to skin breakage on the limbs. He was treated with topical and anti-allergic drugs in several dermatology departments without any significant improvement. After admission, the patient was administered risperidone (0.5 mg) and duloxetine (2 mg/day). One week later, the dose of risperidone was increased to 2 mg/day, and that of duloxetine was increased to 60 mg/day. After 2 weeks of treatment, the patient's sensation of insects crawling and biting disappeared, and his mood stabilized. CONCLUSION: This patient manifested psychiatric behavioral symptoms caused by AD brain atrophy. It was important to re-evaluate the patient's cognitive-psychological status when the patient repeatedly went to the hospital for treatment. Follow-up attention to cognitive function and the consideration of perceptual deficits as early manifestations of AD should be considered.

A Machine Learning Approach to Classifying EEG Data Collected with or without Haptic Feedback during a Simulated Drilling Task.

Artificial Intelligence (AI), computer simulations, and virtual reality (VR) are increasingly becoming accessible tools that can be leveraged to implement training protocols and educational resources. Typical assessment tools related to sensory and neural processing associated with task performance in virtual environments often rely on self-reported surveys, unlike electroencephalography (EEG), which is often used to compare the effects of different types of sensory feedback (e.g., auditory, visual, and haptic) in simulation environments in an objective manner. However, it can be challenging to know which aspects of the EEG signal represent the impact of different types of sensory feedback on neural processing. Machine learning approaches offer a promising direction for identifying EEG signal features that differentiate the impact of different types of sensory feedback during simulation training. For the current study, machine learning techniques were applied to differentiate neural circuitry associated with haptic and non-haptic feedback in a simulated drilling task. Nine EEG channels were selected and analyzed, extracting different time-domain, frequency-domain, and nonlinear features, where 360 features were tested (40 features per channel). A feature selection stage identified the most relevant features, including the Hurst exponent of 13-21 Hz, kurtosis of 21-30 Hz, power spectral density of 21-30 Hz, variance of 21-30 Hz, and spectral entropy of 13-21 Hz. Using those five features, trials with haptic feedback were correctly identified from those without haptic feedback with an accuracy exceeding 90%, increasing to 99% when using 10 features. These results show promise for the future application of machine learning approaches to predict the impact of haptic feedback on neural processing during VR protocols involving drilling tasks, which can inform future applications of VR and simulation for occupational skill acquisition.

The Surgical Outcomes of Modified Intraocular Lens Suturing with Forceps-Assisted Haptics Extraction: A Clinical and Basic Evaluation.

Background/Objectives: Postoperative intraocular lens (IOL) tilt is a risk associated with IOL scleral fixation. However, the cause of IOL tilt during IOL suturing remains unclear. Therefore, this study aimed to evaluate the surgical outcomes of a modified IOL suturing technique and investigate the factors contributing to postoperative IOL tilt and decentration. Methods: We included 25 eyes of 22 patients who underwent IOL suturing between April 2018 and February 2020. A modified IOL suturing technique that decreased the need for intraocular suture manipulation was used. Factors contributing to IOL tilt and decentration were investigated using an intraoperative optical coherence tomography (iOCT) system. Results: The mean postoperative best-corrected visual acuity improved from 0.15 ± 0.45 to -0.02 ± 0.19 (p = 0.02). The mean IOL tilt angle at the last visit after surgery was 1.84 ± 1.28 degrees. The present study reveals that the distance of the scleral puncture site from the corneal limbus had a stronger effect on IOL tilt; meanwhile, the suture position of the haptics had a greater effect on IOL decentration. Conclusions: The modified IOL suturing technique, which avoids intraocular suture handling, had favorable surgical outcomes with improved postoperative visual acuity and controlled IOL tilt and decentration. Accurate surgical techniques and careful measurement of distances during surgery are crucial for preventing postoperative IOL tilt and decentration.

Tactile Sensing and Rendering Patch with Dynamic and Static Sensing and Haptic Feedback for Immersive Communication.

Wearable human-machine interface (HMI) with bidirectional and multimodal tactile information exchange is of paramount importance in teleoperation by providing more intuitive data interpretation and delivery of tactilely related signals. However, the current sensing and feedback devices still lack enough integration and modalities. Here, we present a Tactile Sensing and Rendering Patch (TSRP) that is made of a customized expandable array which consists of a piezoelectric sensing and feedback unit fused with an elastomeric triboelectric multidimensional sensor and its inner pneumatic feedback structure. The primary functional unit of TSRP is mainly featured with a soft silicone substrate with compact multilayer structure integrating static and dynamic multidimensional tactile sensing capabilities, which synergistically leverage both triboelectric and piezoelectric effects. Additionally, based on the air chamber created by the triboelectric sensor and the converse piezoelectric effect, it provides pneumatic and vibrational haptic feedback simultaneously for both static and dynamic perception regeneration. With the aid of the other variants of this unit, the array shaped TSRP is capable of simulating different terrains, geometries, sliding, collisions, and other critical interactive events during teleoperation via skin perception. Moreover, immediate manipulation can be done on TSRP through the tactile sensors. The preliminary demonstration of TSRP interface with a completed control module in robotic teleoperation is provided, which shows the feasibility of assisting certain tasks in a complex environment by direct tactile communication. The proposed device offers a potential method of enabling bidirectional tactile communication with enriched key information for improving interaction efficiency in the fields of robot teleoperation and training.

Effects of Haptic Feedback Interventions in Post-Stroke Gait and Balance Disorders: A Systematic Review and Meta-Analysis.

Background: Haptic feedback is an established method to provide sensory information (tactile or kinesthetic) about the performance of an activity that an individual can not consciously detect. After a stroke, hemiparesis usually leads to gait and balance disorders, where haptic feedback can be a promising approach to promote recovery. The aim of the present study is to understand its potential effects on gait and balance impairments, both after interventions and in terms of immediate effects. Methods: This research was carried out using the following scientific databases: Embase, Scopus, Web of Science, and Medline/PubMed from inception to May 2024. The Checklist for Measuring quality, PEDro scale, and the Cochrane collaboration tool were used to assess the methodological quality and risk of bias of the studies. Results: Thirteen articles were chosen for qualitative analysis, with four providing data for the meta-analysis. The findings did not yield definitive evidence on the effectiveness of haptic feedback for treating balance and gait disorders following a stroke. Conclusions: Further research is necessary in order to determine the effectiveness of haptic feedback mechanisms, with larger sample sizes and more robust methodologies. Longer interventions and pre-post design in gait training with haptic feedback are necessary.

Benefits of using virtual reality in cariology teaching.

BACKGROUND: Virtual Reality (VR) has been widely used as an useful educational tool in modern dentistry and is considered as an alternative training tool adjunct to conventional training methods. OBJECTIVE: This study was designed to investigate the effectiveness of VR haptic-enhanced simulators for training undergraduate dental students during practical cariology pre-clinical caries excavation sessions. METHODS: A total number of 76 students were recruited for this study. Students were randomly divided into 2 groups (38 students each). The experimental group (VR-Start group), students performed caries removal at the VR haptic-enhanced simulator prior to practicing on natural extracted teeth. Conversely, the control group (Natural Tooth-Start Group), students exposed to VR simulation training after practicing on extracted natural teeth. An evaluation questionnaire was disseminated among students to evaluate their self-confidence, perceived clinical skills and their perception of providing better care to patients in the future. They were also invited to express their opinions on the usefulness of VR simulator in comparison with conventional learning methods. RESULTS: The outcome of Chi-square test showed no significant difference in students' response among this study groups (p > 0.05). Moreover, the outcome of this study revealed that both student groups considered virtual reality as a useful learning tool. Majority of students (90%) superiorly ranked experience gained from practicing on natural carious teeth. They also clearly stated that virtual reality allowed them to practice more and improve their self-confidence level as well as eye-hand coordination. CONCLUSIONS: Virtual reality simulator is a useful learning tool which can benefit undergraduate dental students at their pre-clinical stage; but, it cannot totally replace the conventional caries excavation.

Haptic experience of bodies alters body perception.

Research on media's effects on body perception has mainly focused on the role of vision of extreme body types. However, haptics is a major part of the way children experience bodies. Playing with unrealistically thin dolls has been linked to the emergence of body image concerns, but the perceptual mechanisms remain unknown. We explore the effects of haptic experience of extreme body types on body perception, using adaptation aftereffects. Blindfolded participants judged whether the doll-like stimuli explored haptically were thinner or fatter than the average body before and after adaptation to an underweight or overweight doll. In a second experiment, participants underwent a traditional visual adaptation paradigm to extreme bodies, using stimuli matched to those in Experiment 1. For both modalities, after adaptation to an underweight body test bodies were judged as fatter. Adaptation to an overweight body produced opposite results. For the first time, we show adiposity aftereffects in haptic modality, analogous to those established in vision, using matched stimuli across visual and haptic paradigms.

MRI-compatible and sensorless haptic feedback for cable-driven medical robotics to perform teleoperated needle-based interventions.

PURPOSE: Surgical robotics have demonstrated their significance in assisting physicians during minimally invasive surgery. Especially, the integration of haptic and tactile feedback technologies can enhance the surgeon's performance and overall patient outcomes. However, the current state-of-the-art lacks such interaction feedback opportunities, especially in robotic-assisted interventional magnetic resonance imaging (iMRI), which is gaining importance in clinical practice, specifically for percutaneous needle punctures. METHODS: The cable-driven 'Micropositioning Robotics for Image-Guided Surgery' (µRIGS) system utilized the back-electromotive force effect of the stepper motor load to measure cable tensile forces without external sensors, employing the TMC5160 motor driver. The aim was to generate a sensorless haptic feedback (SHF) for remote needle advancement, incorporating collision detection and homing capabilities for internal automation processes. Three different phantoms capable of mimicking soft tissue were used to evaluate the difference in force feedback between manual needle puncture and the SHF, both technically and in terms of user experience. RESULTS: The SHF achieved a sampling rate of 800 Hz and a mean force resolution of 0.26 ± 0.22 N, primarily dependent on motor current and rotation speed, with a mean maximum force of 15 N. In most cases, the SHF data aligned with the intended phantom-related force progression. The evaluation of the user study demonstrated no significant differences between the SHF technology and manual puncturing. CONCLUSION: The presented SHF of the µRIGS system introduced a novel MR-compatible technique to bridge the gap between medical robotics and interaction during real-time needle-based interventions.

Cutaneous Electrohydraulic (CUTE) Wearable Devices for Pleasant Broad-Bandwidth Haptic Cues.

By focusing on vibrations, current wearable haptic devices underutilize the skin's perceptual capabilities. Devices that provide richer haptic stimuli, including contact feedback and/or variable pressure, are typically heavy and bulky due to the underlying actuator technology and the low sensitivity of hairy skin, which covers most of the body. This article presents a system architecture for compact wearable devices that deliver salient and pleasant broad-bandwidth haptic cues: Cutaneous Electrohydraulic (CUTE) devices combine a custom materials design for soft haptic electrohydraulic actuators that feature high stroke, high force, and electrical safety with a comfortable mounting strategy that places the actuator in a non-contact resting position. A prototypical wrist-wearable CUTE device produces rich tactile sensations by making and breaking contact with the skin (2.44 mm actuation stroke), applying high controllable forces (exceeding 2.3 N), and delivering vibrations at a wide range of amplitudes and frequencies (0-200 Hz). A perceptual study with 14 participants achieves 97.9% recognition accuracy across six diverse cues and verifies their pleasant and expressive feel. This system architecture for wearable devices gives unprecedented control over the haptic cues delivered to the skin, providing an elegant and discreet way to activate the user's sense of touch.

[Virtual reality-brain computer interface hand function enhancement rehabilitation system incorporating multi-sensory stimulation].

Stroke is an acute cerebrovascular disease in which sudden interruption of blood supply to the brain or rupture of cerebral blood vessels cause damage to brain cells and consequently impair the patient's motor and cognitive abilities. A novel rehabilitation training model integrating brain-computer interface (BCI) and virtual reality (VR) not only promotes the functional activation of brain networks, but also provides immersive and interesting contextual feedback for patients. In this paper, we designed a hand rehabilitation training system integrating multi-sensory stimulation feedback, BCI and VR, which guides patients' motor imaginations through the tasks of the virtual scene, acquires patients' motor intentions, and then carries out human-computer interactions under the virtual scene. At the same time, haptic feedback is incorporated to further increase the patients' proprioceptive sensations, so as to realize the hand function rehabilitation training based on the multi-sensory stimulation feedback of vision, hearing, and haptic senses. In this study, we compared and analyzed the differences in power spectral density of different frequency bands within the EEG signal data before and after the incorporation of haptic feedback, and found that the motor brain area was significantly activated after the incorporation of haptic feedback, and the power spectral density of the motor brain area was significantly increased in the high gamma frequency band. The results of this study indicate that the rehabilitation training of patients with the VR-BCI hand function enhancement rehabilitation system incorporating multi-sensory stimulation can accelerate the two-way facilitation of sensory and motor conduction pathways, thus accelerating the rehabilitation process.

Implementation of machine learning models as a quantitative evaluation tool for preclinical studies in dental education.

PURPOSE AND OBJECTIVE: Objective, valid, and reliable evaluations are needed in order to develop haptic skills in dental education. The aim of this study is to investigate the validity and reliability of the machine learning method in evaluating the haptic skills of dentistry students. MATERIALS AND METHODS: One-hundred fifty 6th semester dental students have performed Class II amalgam (C2A) and composite resin restorations (C2CR), in which all stages were evaluated with Direct Observation Practical Skills forms. The final phase was graded by three trainers and supervisors separately. Standard photographs of the restorations in the final stage were taken from different angles in a special setup and transferred to the Python program which utilized the Structural Similarity algorithm to calculate both the quantitative (numerical) and qualitative (visual) differences of each restoration. The validity and reliability analyses of inter-examiner evaluation were tested by Cronbach's Alpha and Kappa statistics (p = 0.05). RESULTS: The intra-examiner reliability between Structural Similarity Index (SSIM) and examiners was found highly reliable in both C2A (α = 0.961) and C2CR (α = 0.856). The compatibility of final grades given by SSIM (53.07) and examiners (56.85) was statistically insignificant (p > 0.05). A significant difference was found between the examiners and SSIM when grading the occlusal surfaces in C2A and on the palatal surfaces of C2CR (p < 0.05). The concordance of observer assessments was found almost perfect in C2A (κ = 0.806), and acceptable in C2CR (κ = 0.769). CONCLUSION: Although deep machine learning is a promising tool in the evaluation of haptic skills, further improvement and alignments are required for fully objective and reliable validation in all cases of dental training in restorative dentistry.

Interoceptive training with real-time haptic versus visual heartbeat feedback.

The perception of signals from within the body, known as interoception, is increasingly recognized as a prerequisite for physical and mental health. This study is dedicated to the development of effective technological approaches for enhancing interoceptive abilities. We provide evidence of the effectiveness and practical feasibility of a novel real-time haptic heartbeat supplementation technology combining principles of biofeedback and sensory augmentation. In a randomized controlled study, we applied the developed naturalistic haptic feedback on a group of 30 adults, while another group of 30 adults received more traditional real-time visual heartbeat feedback. A single session of haptic, but not visual heartbeat feedback resulted in increased interoceptive accuracy and confidence, as measured by the heart rate discrimination task, and in a shift of attention toward the body. Participants rated the developed technology as more helpful and pleasant than the visual feedback, thus indicating high user satisfaction. The study highlights the importance of matching sensory characteristics of the feedback provided to the natural bodily prototype. Our work suggests that real-time haptic feedback might be a superior approach for strengthening the mind-body connection in interventions for physical and mental health.

The impact of virtual reality haptic simulators in pre-clinical restorative dentistry: a qualitative enquiry into dental students' perceptions.

PURPOSE: In the realm of restorative dentistry, the integration of virtual reality haptic simulation (VRHS) for learning operative skills has garnered varied perceptions among dental students. Therefore, the aim of this study was to delve deep into undergraduates dental students' perceptions related to the impact of VRHS in pre-clinical restorative dentistry. METHODS: A homogeneous purposive sampling method was utilized to gather data from third-year undergraduate dental students (n = 23) at the College of Dental Medicine, Qatar University, to thoroughly investigate their views on the impact of VRHS on their learning experience in preparing a standard class I cavity. An explorative qualitative method using face-to-face focus group sessions were conducted in English during 2023. Focus group sessions were recorded and transcribed using Microsoft Teams. Two authors independently read the transcripts, coded the text, and manually analyzed text using an inductive thematic approach. RESULTS: A total of 21 (91.3%) students participated in this study. Analysis of 3 focus group interviews revealed five primary themes summarized with the term "MASTR" (M = manual dexterity, A = assessment, S = sequence, T = training, and R = realism). Based on frequency of reported themes, students perceived realism/ lifelike nature of VRHS requiring further enhancement to achieve the desired learning objective. CONCLUSION: Although, VRHS play a crucial role in modern dental education, offering innovative solutions for training, evaluation, and feedback, the need to enhance their ability to simulate real-life dental procedures and learning environment (realism), coupled with interactive and immersive learning experiences were the most frequently raised theme by students. In terms of curriculum design and learning pedagogies, dental educators should consider the appropriate sequence when integrating VRHS within the undergraduate curricula.