PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Video feedback”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 541 records · Page 30Linked to original sources

Strategies to support families of children with end-stage renal failure.

The burden of care for families looking after children with end-stage renal failure can be considerable, especially when it involves home peritoneal dialysis and supplementary feeding. Good communication with the family and between team members delivering the multidisciplinary care is essential. Stress may be partly reduced by meeting the information needs and supplementing the spoken word with booklets, videos, tape-recorded interviews and play preparation for children. Families greatly appreciate a continuum of care between the hospital and community which is enhanced by team members visiting the home, nursery/school and primary care physician to impart and update knowledge. Respite care is essential for home dialysis patients. It can be enhanced by an evening baby-sitting service and the involvement of a home care renal nurse, as well as a holiday support strategy. Participation of the families in a regular parents support group provides not only an opportunity to integrate families into the unit, but also allows direct feedback on issues affecting the quality of care.

Child↗

Using a virtual reality temporal bone simulator to assess otolaryngology trainees.

OBJECTIVE: The objective of this study is to determine the feasibility of computerized evaluation of resident performance using hand motion analysis on a virtual reality temporal bone (VR TB) simulator. We hypothesized that both computerized analysis and expert ratings would discriminate the performance of novices from experienced trainees. We also hypothesized that performance on the virtual reality temporal bone simulator (VR TB) would differentiate based on previous drilling experience. STUDY DESIGN: The authors conducted a randomized, blind assessment study. METHODS: Nineteen volunteers from the Otolaryngology-Head and Neck Surgery training program at the University of Toronto drilled both a cadaveric TB and a simulated VR TB. Expert reviewers were asked to assess operative readiness of the trainee based on a blind video review of their performance. Computerized hand motion analysis of each participant's performance was conducted. RESULTS: Expert raters were able to discriminate novices from experienced trainees (P < .05) on cadaveric temporal bones, and there was a trend toward discrimination on VR TB performance. Hand motion analysis showed that experienced trainees had better movement economy than novices (P < .05) on the VR TB. CONCLUSION: Performance, as measured by hand motion analysis on the VR TB simulator, reflects trainees' previous drilling experience. This study suggests that otolaryngology trainees could accomplish initial temporal bone training on a VR TB simulator, which can provide feedback to the trainee, and may reduce the need for constant faculty supervision and evaluation.

Cadaver↗

Small-group videotape training for psychotherapy skills development.

OBJECTIVE: Psychotherapy instructors have used video technology to train residents for over 40 years. Though it has met with some controversy, many will argue that videotape review is essential for self-directed learning and accurate psychotherapy supervision. METHODS: The author describes a technique of small-group videotape training as provided in a psychiatry residency training program. RESULTS: He reviews the merits and limitations of this format and suggests simple and inexpensive technical approaches to augment this training. CONCLUSION: The author concludes that small-group videotape training is an efficient psychotherapy training format that encourages self-monitoring and the exchange of supportive peer feedback.

Clinical Competence↗

Defensive evaluation of antismoking messages among college-age smokers: the role of possible selves.

This study hypothesized that individuals respond to antismoking messages in a biased or defensive manner to the degree that smoking is a personally relevant activity for them. The authors operationalized the personal relevance of smoking variously as smoking behavior (smoking status, rate, duration, and recent attempts to quit), endorsement of the smoker stereotype, and importance of smoking behavior as an identity within the self-concept (current self and possible selves). In the experiment, smokers (n = 82) and nonsmokers (n = 105) privately viewed several antismoking video segments. Smoking status, current smoking identity, and long-term future smoking identity were significantly associated with a defensive evaluation of antismoking messages. The study concludes that the concept of possible selves (H. Markus & P. Nurius, 1986) is critical in understanding college-age smoking and in the design of effective antismoking campaigns.

Adolescent↗

Training, assessment and competency in gynaecologic surgery.

The trainee gynaecologist requires specific teaching to achieve competency in gynaecological surgery. Basic skills such as knot tying and suturing should be acquired outside the operating theatre. They can be learned on simulations, including bench models, using synthetic materials, life-like models and animal tissue. Video training equipment is useful for the development of basic laparoscopic hand-eye coordination. Intermediate and advanced skills require simulations using more sophisticated bench models, live animals and virtual reality computerised systems. Structured teaching and assessment methods are essential. Surgical skills training models should be reliable and valid, and can be incorporated into an objective structured clinical examination, which could be used to assess individual development and allow progression through a training programme. Simulation training does translate into improved operative performance. Supervised operating experience on patients is crucial to training and should be assessed regularly using a global rating form with constructive feedback to facilitate improvement.

Clinical Competence↗

Improving the skills of doctors in giving distressing information.

In response to the growing awareness of the need to convey distressing information effectively, four workshops were held for doctors across Britain with the aim of improving skills, knowledge and attitudes. From the unexpectedly large response of 441 nominations, 20 participants were selected for each workshop. Participants identified four major concerns: how to do it; where to give distressing information; how to deal with collusion; and how to survive mentally in the work. After sessions on these areas, participants interviewed a simulated patient and were recorded on videotape for subsequent feedback. The results showed that after brief training, 91% of all participants gave a warning of distressing information, 85% gave the information at the patient's pace, but only 5% attempted to 'pick up the pieces'. Further work is required on this key aspect of clinical work.

Audiovisual Aids↗

Target-directed running in gymnastics: a preliminary exploration of vaulting.

Research to date has demonstrated the importance of running speed and an accurate take-off on gymnastics vaulting performance (Krug et al., 1998; Bohne et al., 2000). Current training practice for gymnastics vaulting is to stereotype the 15-25 m run-ups to the board, which assumes that a fast and reliable approach is best controlled predominantly without visual feedback. Incidences where gymnasts make errors during their run-ups, often landing onto the back of the board, occur frequently, even at the international level. The standard deviation method (e.g. Lee et al., 1982) for identifying visual regulation in long jump run-ups was employed in this first exploration of gymnastics vaulting to examine whether visual regulation processes are utilised. Secondly, the question of how a small number of gymnasts can run fast during the approach and perform more difficult vaults was addressed. Five elite female gymnasts aged 13-15 years performed five round-off entry vaults. One panning 50 Hz video camera recorded each trial from an elevated platform to evaluate the approach step, hurdle, and round-off characteristics, whilst two 250 Hz cameras recorded vaulting performance. Two qualified judges viewed each vaulting trial and provided a performance score. A precursor for a fast take-off from the board when vaulting is to utilise vision early to control the approach kinematics (p = 0.02). High take-off velocity was directly related to judge's score (p = 0.03). Coaches need to supplement gymnasts' vault training to include exercises that improve the gymnasts' ability to visually regulate their gait pattern whilst running.

Adolescent↗

The use of multimedia in the informed consent process.

OBJECTIVE: The goal of the project was to create recommendations and design specifications for a multimedia tool to enhance the informed consent process for clinical trials. The authors focused on the needs of patients with potential cognitive impairment. DESIGN: The authors first performed a needs assessment using focus groups and interviews with health care researchers, institutional review board members, and three groups of patients (who had depression, breast cancer, or schizophrenia). Their feedback was incorporated into the design of a prototype multimedia tool. The design included general modules with information about clinical trials and informed consent as well as trial-specific modules. The authors then used the resulting prototype multimedia tool for informed consent in follow-up focus groups and interviews to obtain feedback on the feasibility and potential effectiveness of using such a tool routinely for clinical trials. RESULTS: The authors showed that it was feasible to adapt a structured multimedia informed consent system to a specific clinical trial and to incorporate techniques to improve the understandability of informed consent content. Patients generally felt the prototype system was useful and could replace the paper document. They felt using the system would be less stressful, because they would have a greater sense of control and could proceed at their own pace. They liked the hierarchic and modular approach to providing information and felt that the use of video made information more understandable. Researchers and institutional review board members also found the system to be valuable in these ways but had concerns about how to review the system for potential biases in presentation and about the legal issues associated with replacing the paper document.

Adult↗

PI3-kinase is essential for ADP-stimulated integrin alpha(IIb)beta3-mediated platelet calcium oscillation, implications for P2Y receptor pathways in integrin alpha(IIb)beta3-initiated signaling cross-talks.

Phosphatidylinositol 3-kinase (PI3K) pathway is important for platelet activation. Recent studies showed that PI3K and oscillative calcium could cross talk to each other and positively regulate integrin alpha (IIb)beta3-mediated outside-in signaling. However, the mechanism of this feedback regulation remains to be further characterized. Here we found that treatments of both PI3K inhibitor wortmannin and P2Y1 inhibitor A3P5P could inhibit granular secretion in platelets. Additionally, when RGD-substrate adherent platelets were treated with the ADP scavenger apyrase to deplete the granular-released ADP, their attachments in engaging with substrates became looser and the frequency of calcium oscillation decreased. Since it is known that ADP stimulates the PI3K and calcium signal primarily through P2Y12 and P2Y1 receptors respectively, our data indicated that integrin alpha(IIb)beta3 downstream PI3K and calcium activation might be not completely coupled to integrin associated signaling complex, but in part through feedback stimulation by granular released ADP. Our data indicates the important roles of PI3K and granular released ADP in coordinating the feedback regulations in integrin alpha(IIb)beta3-mediated platelet activation.

Actins↗

Application of robotics in congenital cardiac surgery.

Over the past 5 years, robotic systems that combine advanced endoscopic imaging with computer-enhanced instrument control have been used for both coronary revascularization and intracardiac procedures in adults. In addition, endoscope positioning systems and articulated instruments with a robotic wrist mechanism have further expanded the potential applications for robotics in cardiac surgery. In pediatric cardiac surgery, potential applications can be divided into simple scope manipulation versus the use of 3-dimensional imaging and a robotic wrist for dissection and reconstruction. A voice-controlled robotic arm for scope manipulation can facilitate current pediatric thoracoscopic procedures such as ligation of patent ductus arteriosus and division of vascular rings. By using an advanced imaging system along with a robotic wrist, more complex extracardiac and even intracardiac procedures can be performed in children. Examples include coarctation repair, septal defect repair, and mitral or tricuspid valvuloplasty. Furthermore, with adequate intracardiac imaging, a robot-assisted off-pump approach to intracardiac pathology is conceivable. New real-time 3-dimensional echocardiography now offers sufficient resolution to enable such procedures, while the addition of instrument tracking, haptic feedback, and novel tissue fixation devices can facilitate safe and reliable intracardiac repair without extracorporeal circulation.

Cardiac Surgical Procedures↗

Robotics and telesurgery--an update on their position in laparoscopic radical prostatectomy.

Laparoscopy is handicapped by the reduction of the range of motion from six to only four degrees of freedom. In complicated cases (i.e. radical prostatectomy), there is often a crossing of the hands of surgeon and assistant. Finally, standard laparoscopes allow only 2D-vision. This has a major impact on technically difficult reconstructive procedures such as laparoscopic radical prostatectomy. Solutions include the understanding of the geometry of laparoscopy, but also newly developed surgical robots. During the last five years, there has been an increasing development and experience with robotics in urology. This article reviews the actual results focussing on the benefits and problems of robotics in laparoscopic radical prostatectomy. Own experiences with robot-assisted surgery include more than 1200 laparoscopic radical prostatectomies using a voice-controlled camera-arm (AESOP) as well as six telesurgical interventions with the da Vinci-system. Substantial experimental studies have been performed focussing on the geometry of laparoscopy and new training concepts such as perfused pelvitrainers and models for simulation of urethrovesical anastomosis. The recent literature on robotics in urology has been reviewed based on a MEDLINE/PUBMED research. The geometry of laparoscopy includes the angles between the instruments which have to be in a range of 25 degrees to 45 degrees ; the angles between the instrument and the working plane that should not exceed 55 degrees ; and the bi-planar angle between the shaft of the needle holder and the needle which has to be adapted according to the anatomical situation in range of 90 degrees to 110 degrees . 3-D-systems have not yet proved to be effective due to handling problems such as shutter glasses, video helmets or reduced brightness. At the moment, there are only two robotic surgical systems (AESOP, da Vinci) in clinical use, of which only the da Vinci provides stereovision and all six degrees of freedom (DOF). To date, more than 3000 laparoscopic radical prostatectomies have been performed worldwide at 92 centres with this system. The main advantage of the system represents the translation of open surgical skills to laparoscopy. Despite recent development of basic tools (e.g. bipolar forceps) for the da Vinci robot, investment and maintenance costs still represent the major problem of the device. Additionally, the device does not provide any haptic sense (i.e. tactile feedback). Robotic surgery represents a turning point of surgical research. However, broad use of robotic systems is limited mainly because of the high investment and running costs. Interestingly, more than in the field of cardiac surgery, there seems to be a need for telemanipulators in urology, mainly to reduce the learning curve of standard laparoscopy. However, new training concepts used in combination with mono-tasking computerized robots (AESOP) have proved their efficacy associated with a significant cost reduction.

Journal Article↗

A light-emitting diode light standard for photo- and videomicroscopy.

A light calibration system consisting of a compact light-emitting diode (LED) source with feedback control of intensity is described. The source is positioned in the focal plane of the microscope objective and produces flat-field illumination of up to 31 microW. The source can be easily used to determine the performance of microscope optics and camera response. It can also be used as a standard light source for calibration of experimental systems. Selectable light intensities are produced by controlling the LED input power via a feedback circuit consisting of a photodiode that detects output light intensity. Spectral coverage extends between 550 and 670 nm using green, yellow and red LEDs mounted side by side, which are selected individually. The LED chips are encapsulated in plastic diffusers which homogenize the light, and a flat field of illumination is obtained through a thin 1-mm-diameter aperture positioned directly over each chip. Provision is made for insertion of Ronchi rulings over the aperture to enable measurements of contrast modulation in a uniform field. The light may be pulse-modulated to assess camera response times and the device can be synchronized with video frames. Narrow bandpass interference filters can be placed between the objective lens and the LED source to produce monochromatic light without affecting the spacing of controlled light intensities since emission spectra do not shift appreciably over the range of LED powers chosen in this design. Results of tests using controlled light intensity and uniform illumination are presented.

Calibration↗

Portfolio learning in general practice vocational training--does it work?

Reflective learning has been widely addressed as an important learning mechanism in the educational literature. The creation of portfolios has been seen as a mechanism to promote this, though there has been little exploration of the place of a portfolio in general practice training. This study examined the introduction of a model of a portfolio learning strategy into one training region. The model had been developed by previous pilot work. The study explored the model in terms of its usefulness in general practice training and its relationship to reflective learning. An educational facilitator was used to support this introduction. Workshops and written material were developed to disseminate and refine ideas generated in the pilot study. This was followed by visits to trainer/general practice registrar (GPR) pairs over a 2-year period. These visits included semistructured interviews, which were tape-recorded and analysed using qualitative methods. Additional written resources, video and audio material as well as new workshops were designed with the researched participants in order to promote the development of the concepts of portfolio learning. Sixty interviews were carried out over a 2-year period with 44 pairs of trainers and GPRs. This included a total of 27 trainers and 44 registrars. Eighteen pairs were interviewed twice. Two focus groups were used at the end of the project. Portfolios have a place to play in general practice vocational training. They act as a bridge between hospital and general practice. They can be used to develop a learner-centred curriculum, explore difficult emotive concerns and facilitate feedback. They do not suit all learning styles. Their use is determined by a cost-benefit analysis described in this study.

Education, Medical, Graduate↗

Visual tracking and recognition using appearance-adaptive models in particle filters.

We present an approach that incorporates appearance-adaptive models in a particle filter to realize robust visual tracking and recognition algorithms. Tracking needs modeling interframe motion and appearance changes, whereas recognition needs modeling appearance changes between frames and gallery images. In conventional tracking algorithms, the appearance model is either fixed or rapidly changing, and the motion model is simply a random walk with fixed noise variance. Also, the number of particles is typically fixed. All these factors make the visual tracker unstable. To stabilize the tracker, we propose the following modifications: an observation model arising from an adaptive appearance model, an adaptive velocity motion model with adaptive noise variance, and an adaptive number of particles. The adaptive-velocity model is derived using a first-order linear predictor based on the appearance difference between the incoming observation and the previous particle configuration. Occlusion analysis is implemented using robust statistics. Experimental results on tracking visual objects in long outdoor and indoor video sequences demonstrate the effectiveness and robustness of our tracking algorithm. We then perform simultaneous tracking and recognition by embedding them in a particle filter. For recognition purposes, we model the appearance changes between frames and gallery images by constructing the intra- and extrapersonal spaces. Accurate recognition is achieved when confronted by pose and view variations.

Algorithms↗

Learning of Sequential Finger Movements in Man: A Combined Kinematic and Positron Emission Tomography (PET) Study.

The cerebral structures participating in learning of a manual skill were mapped with regional cerebral blood flow (rCBF) measurements and positron emission tomography in nine healthy volunteers. The task was a complicated right-hand finger movement sequence. The subjects were examined at three stages: during initial practice of the finger movement sequence, in an advanced stage of learning, and after they had learnt the finger movement sequence. Quantitative evaluation of video tapes and electromyographic records of the right forearm and hand muscles demonstrated that the finger movements significantly accelerated and became more regular. Significant mean rCBF increases were induced in the left motor hand area, the left premotor cortex, the left supplementary motor area, the left sensory hand area, the left supplementary sensory area and the right anterior lobe of the cerebellum. During the learning process significant depressions of the mean rCBF occurred bilaterally in the superior parietal lobule, the anterior parietal cortex and the pars triangularis of the right inferior frontal cortex. The mean rCBF increases in these structures during the initial stage of learning were related to somatosensory feedback processing and internal language for the guidance of the finger movements. These activations disappeared when the subjects had learnt the finger movement sequence. Conversely, the mean rCBF significantly rose during the course of learning in the midsector of the putamen and globus pallidus on the left side. It is suggested that during the learning phase of this movement sequence, the basal ganglia were critically involved in the establishment of the final motor programme.

Journal Article↗

Deprivation of straw bedding alters PGF(2alpha)-induced nesting behaviour in female pigs.

Sows are highly motivated to build a maternal nest on the day preceding parturition. A model for nest building has been established in pigs, in which exogenously administered prostaglandin F(2alpha) (PGF(2alpha)) may be used to elicit nesting behaviour in cyclic, pseudopregnant and pregnant pigs. The aim of this experiment was to examine the effects of deprivation of straw bedding on PGF(2alpha)-induced nest building in pseudopregnant Large White gilts. Oestradiol valerate injections (5 mg/day) were given on days 11-15 of the oestrous cycle to induce pseudopregnancy. The pigs were housed individually in a pen (2.8x1.7 m) and provided with 2-kg fresh straw each day. On the test day, on day 46 or 47 of pseudopregnancy, half of the pigs were deprived of straw (substrate effect) and they were injected intramuscularly with saline or 15 mg of PGF(2alpha) (Lutalyse, Upjohn) (treatment effect) allocated in a Latin-square design. Behaviour was recorded onto video tapes for 1 h either side of treatment for analysis using a computerised event recorder. PGF(2alpha)-treated pigs housed in bare or strawed pens showed significantly higher frequencies of pawing and rooting, and stood for longer than saline-treated controls. This treatment effect has been previously shown to be comparable to pre-partum nest building. The removal of straw significantly reduced the frequency of pawing and the duration of rooting by PGF(2alpha)-treated pigs. The results demonstrate that nesting behaviour can be initiated by exogenously administered PGF(2alpha) and is further modified by the provision of straw. This suggests that PGF(2alpha)-induced nesting behaviour is subject to environmental feedback.

Journal Article↗

Feeding kinematics of phyllomedusine tree frogs.

Previous studies have demonstrated that the phyllomedusine hylids possess highly protrusible tongues, a derived characteristic within the family Hylidae. In the present study, the kinematics of the feeding behavior of a phyllomedusine species, Pachymedusa dacnicolor, was analyzed using high-speed video (180 frames s-1). Its behavior was compared with that of Hyla cinerea, a species with a weakly protrusible tongue. P. dacnicolor exhibits a faster rate of tongue protraction, a longer gape cycle and more variable feeding kinematics than H. cinerea. In addition, the tongue is used in a unique 'fly-swatter' fashion, to pin the prey to the substratum as the frog completes the lunge. The rapid tongue protraction, extended gape cycle and fly-swatter action may have evolved in response to a diet of large, rapidly moving insects. In addition, several duration variables of the feeding cycle were greater for misses than for captures and drops, which suggests that sensory feedback rather than biomechanics controls gape cycle duration.

Analog-Digital Conversion↗

Auditory biofeedback in spastic diplegia.

Using a simple auditory feedback device that produces a continuous buzzing signal on heel contact, we studied the effects of augmented auditory biofeedback on the gait of four spastic diplegic children. The purpose of the biofeedback was to attempt to increase dorsiflexion at heel strike without causing other compensatory changes at the knee and hip, which might lead to crouch gait. We measured velocity, stride length, and thigh, knee, and ankle angles at the heel strike, midswing, and toe-off phases of gait. Four subjects, aged 5-8 years, were given a standard gait training program, supplemented with biofeedback two times per week in a clinical setting and 1 h daily in a home program over an 8-week period. Three computer video gait analyses of the sagittal plane were conducted without biofeedback in the pre- and posttraining conditions and twice with biofeedback over the course of treatment. We performed linear regression analysis of joint angles at heel strike, midswing, and toe-off as a function of days into the study for each patient. Angle-angle diagrams for a test subject before, during, and after treatment indicate changes toward a normal gait pattern with biofeedback. The linear regression analysis showed a statistically significant (p less than 0.01) shift toward dorsiflexion at heel strike with repeated exposure to biofeedback. A compensatory crouch gait was not induced. The linear regression analyses for hip and knee angles were not statistically significant (p greater than 0.25), indicating a disassociation of movement among hip, knee, and ankle.

Acoustic Stimulation↗