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PubMed1979

Heart rate and finger pulse amplitude during muscular relaxation with frontalis versus forearm EMG feedback.

Twenty-nine volunteers participated in a one-session experiment consisting of 10 min rest followed by a 30 min treatment period. Brief relaxation instructions were given at the beginning of the rest period. The treatment was either frontalis EMG feedback, forearm EMG feedback, or non-contingent stimulation. The two feedback groups showed EMG decreases in their respective target muscles during the no-feedback rest period, with no further decrease during feedback training, indicating that feedback was no more effective than relaxation instructions. Heart rate decreased significantly in both feedback groups. Finger pulse amplitude decreased significantly in the forearm feedback group. It is pointed out that the latter change does not necessarily indicate peripheral vasoconstriction, but may be due to a fall in pulse pressure as a consequence of increased blood flow to the relaxing muscles. The results are unsupportive of the assumption that frontalis relaxation is particularly effective in inducing a generalized relaxation.

Adult↗
PubMed2004

The effect of auditory feedback on phonation threshold pressure measurement.

The effect of auditory feedback on phonation threshold pressure (Pth) measurement was investigated in 14 females with normal, untrained voices. Two measurement systems (Glottal Enterprises MS 100--circumferentially vented mask and Kay Elemetrics Aerophone II--non-circumferentially vented mask) were examined under three conditions: (1) masked, (2) no mask, and (3) masked with enhanced auditory feedback-acoustic signal placed at ears through headphones. Masked with enhanced auditory feedback, in addition to subject training, significantly lowered Pth values regardless of mask design. The amount of auditory feedback provided by different mask designs was investigated and revealed a significant difference. Clinical significance of different auditory feedback levels provided by the two mask designs was investigated. Direct comparison of the mean values between systems was not possible because of each system's design and calibration. Comparisons were accomplished by subtracting means of select-paired conditions (masked/no mask; masked/masked plus masked with enhanced auditory feedback) within each system and then comparing these difference scores from the same paired conditions between each system. No clinical significance in difference scores was revealed because of varying amounts of auditory feedback provided by the masks. Results support the use of enhanced auditory feedback, in addition to subject training, when measuring Pth.

Adult↗
PubMed2000

Influencing NSAID prescribing in primary care using different feedback strategies.

The Audit Commission endorsed the role of the prescribing adviser in promoting safe, rational and cost-effective prescribing by general medical practitioners (GPs). However, whether such roles should involve practice visits, facilitation of educational meetings, production of local bulletins, or a combination of these and other approaches is unclear. Few UK studies have investigated the best methods to influence prescribing on a large scale in primary care. The present study was designed to determine the effectiveness of active compared to passive practice specific prescribing feedback. The programme focused on non-steroidal anti-inflammatory drugs (NSAIDs) since concern has been expressed about their use, which accounts for 4% of volume and 5% of the cost of UK National Health Service drugs prescribed in primary care, Sixty-six of the 91 general medical practices contracted to Gwent Health Authority agreed to participate in the study and were randomly stratified by practice size, locality, fund-holding and dispensing status into 2 groups. Group 1 received active feedback via practice visits from the pharmaceutical prescribing adviser to present prescribing analysis and cost data (PACT) concerning NSAID use. Group 2 received passive feedback, a practice specific prescribing analysis workbook that contained similar information to that given to Group 1 practices. Practices not wishing to enter the study were used as a self selected reference group (Group 3) which received no information on NSAIDs from the prescribing adviser. Practice visits and the distribution and completion of workbooks occurred between September 1993 and March 1994, PACT data for all NSAIDs was used to identify changes in prescribing before and after the programme. A combination of 27 indicators, in terms of items and cost per 1000 patients, were chosen to identify overall changes and potential switches between individual drugs, or to generic alternatives. Comparison of the practices in each of the three groups at analysis revealed similar distribution in terms of stratification criteria. Eleven (38%) Group 2 practices returned completed workbooks. Overview indicators (those not targeted) showed similar trends of either increase or decrease, in cost and volume, across all three groups, whereas targeted indicators demonstrated a more mixed picture between groups. In summary the total number of statistically significant changes for targeted indicators in Groups 1, 2, and 3 were 10, 8 and 1 (changes in items per 1000 patients), and 12, 10 and 3 (changes in cost per 1000 patients) respectively. Targeted indicators revealed more statistically significant changes in Group 1 (active feedback) than Group 2 passive feedback) which showed more changes than Group 3 (reference group). Active feedback was more effective at bringing about a required change than the use of passive feedback; both approaches had more impact than that registered by the reference group. The Group 2 analysis presented included both responders and non-responders, thus a more marked benefit of the workbook was perhaps masked. These results have implications for the future provision of prescribing advice to practices. Advisers currently use both active and passive methods to provide prescribing feedback to practices. The high resource intensiveness of practice visits leads many authorities to rely increasingly on less effective methods such as bulletins. Evaluation of the cost effectiveness of methods used to influence prescribing are required.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1998

A Broader Theoretical Model for Feedback in Ambulatory Care.

Ask faculty if they provide feedback and they will likely reply "Sure, it's important, I do it all the time". Ask medical students if they receive feedback and they may say, "We hardly ever get it". Ask most residents if they receive feedback and you get "Rarely, but it's not that helpful anyway". How is it that these perceptions are so strikingly different? Can they be talking about the same thing? If we wish to improve the educational value of feedback, we must understand these differences. One useful clue is provided by the adage "do as I say, not as I do". This saying suggests that there are two types of feedback: that which we can measure against a standard and describe (traditional feedback), and that which comes from being immersed in real situations (situated feedback). This dichotomy is a useful construct from which to understand feedback.

Journal Article↗
PubMed1997

The effect of formal feedback sessions on test security for a clinical practice examination using standardized patients.

OBJECTIVE: To determine the effects of formal feedback on test security for a clinical practice examination administered to successive rotations over a year's time. METHOD: A seven case clinical performance examination was administered to ten rotations of students throughout an academic year in a required Ambulatory Care Clerkship. Three of the cases were developed at Saint Louis University School of Medicine (SLU); four of the cases were developed by the National Board of Medical Examiners (NBME). Immediately following each examination, the examinees participated in a feedback session for just the three SLU cases: checklists were displayed, and details of the cases were discussed. No feedback on the four NBME cases was provided. Student performance in successive rotations on the three cases in which students were given detailed feedback by the faculty was compared with performance on the four cases in which no feedback was given. SAMPLE: Data were collected from 119 students. RESULTS: The interaction of case and group was not significant, indicating no difference in the trend over the ten groups between the three cases for which feedback was provided and the four cases for which it was not. The results showed no significant increasing trend over the ten rotation groups for either cases where feedback was given or withheld. CONCLUSION: The results suggest that the formal feedback sessions did not pose a threat to test security.

Journal Article↗
PubMed2000

Does failure hurt? The effects of failure feedback on pain report, pain tolerance and pain avoidance.

In this study an experiment was conducted to examine whether failure experiences have an effect on pain report, pain tolerance and pain avoidance. Furthermore, it was investigated if negative affectivity (NA) affected the impact of failure feedback on pain report, either as a mediator, in the case of negative state affect, or as a moderator when NA as a personality trait was considered. Fifty-four healthy female volunteers were included and randomly assigned to one of three conditions: (1) failure feedback; (2) success feedback; (3) neutral control task. After the manipulation, subjects were given a cold pressor task in order to obtain pain measures. Regarding the effects of failure feedback on pain report, it was found that, in comparison with success feedback, failure feedback led to increased pain report. With regard to pain tolerance, pain was tolerated for longer when preceded by success feedback than when preceded by failure feedback. Differences between failure and control conditions did not reach significance. With regard to pain avoidance, no differences between the conditions were found. The hypothesized mediating role of negative state affect was not found. Though in the hypothesized direction, no significant effect was found for NA-trait moderating the influence of failure on pain. The discussion focuses on a number of research questions that remain to be answered, and the clinical relevance of the effects of failure and success experiences on pain report and pain tolerance.

Adolescent↗
PubMed2002

Biomechanics feedback for rowing.

Factors that affect boat speed are important determinants of rowing performance and should form the basis of feedback to rowers and their coaches. Biomechanical analysis of rowing has led to variables that are causally linked to boat speed. With modern technology, these variables can be measured and feedback can be presented instantaneously on-water, or be presented simultaneously with video after the event. This paper demonstrates the links between the criterion of success in rowing, the time for completing 2000 m and the forces acting on the boat, and describes an instrumentation system for providing feedback of these variables to rowers and coaches. These feedback techniques have been used with rowers from national to Olympic competition standard. Aspects of technique have been linked to the determinants of boat speed and several examples are presented here. The motor learning literature supports the effectiveness of kinetic information feedback for the improvement of motor skill and provides a relevant conceptual framework for the improvement of rowing performance. However, although rowers and their coaches value this feedback, further research must be undertaken to establish a sound basis for comparing the effectiveness of such feedback compared with traditional styles, such as verbal feedback of performance.

Biofeedback, Psychology↗
PubMed2005

Effect of augmented feedback on motor function of the affected upper extremity in rehabilitation patients: a systematic review of randomized controlled trials.

OBJECTIVE: Assessment of the available evidence regarding the effect of augmented feedback on motor function of the upper extremity in rehabilitation patients. METHODS: A systematic literature search was performed to identify randomized controlled trials that evaluated the effect of augmented feedback on motor function. Two reviewers systematically assessed the methodological quality of the trials. The reported effects were examined to evaluate the effect of therapeutic interventions using augmented feedback and to identify a possible relationship with patient characteristics, type of intervention, or methodological quality. RESULTS: Twenty-six randomized controlled trials were included, 9 of which reported a positive effect on arm function tests. Follow-up measurements were performed in 8 trials, 1 of which reported a positive effect. Different therapeutic interventions using augmented feedback, i.e. electromyographic biofeedback, kinetic feedback, kinematic feedback, or knowledge of results, show no difference in effectiveness. CONCLUSION: No firm evidence was found of effectiveness regarding the use of augmented feedback to improve motor function of the upper extremity in rehabilitation patients. Future studies should focus more on the content, form and timing of augmented feedback concerning the therapeutic intervention. It should be emphasized that motor learning effects can only be determined by re-examining the population after a follow-up period.

Arm↗
PubMed2004

Cortico-striatal contributions to feedback-based learning: converging data from neuroimaging and neuropsychology.

The striatum has been widely implicated in cognition, but a precise understanding of its role remains elusive. Here we present converging evidence for the role of the striatum in feedback-based learning. In a prior functional imaging study, healthy controls showed striatal activity during a feedback-based learning task, which was decreased when the same task was learned without feedback. In the present study, we show that individuals with striatal dysfunction due to Parkinson's disease are impaired on the feedback-based task, but not on a non-feedback version of the same task. Parkinson's patients and controls also used different learning strategies depending on feedback structure. This study provides direct behavioural evidence from humans that cortico-striatal systems are necessary for feedback-based learning on a cognitive task. These findings also link between learning impairments in Parkinson's disease and the physiological and computational evidence for the role of midbrain dopaminergic systems in feedback processing.

Aged↗
PubMed1986

Changes in heart rate during feedback control of respiration.

Subjects received one of eight treatments: practice at increasing heart rate with heart-rate feedback, practice at decreasing heart rate with heart-rate feedback, practice at increasing heart rate without heart-rate feedback, practice at decreasing heart rate without heart-rate feedback, practice at increasing respiration rate with respiratory feedback, practice at decreasing respiration rate with respiratory feedback, practice at increasing respiration rate with respiratory instructions only, practice at decreasing respiration rate with respiratory instructions only. Heart rate, Respiration rate, and Respiration depth were measured. Analysis indicated that subjects who controlled respiration with respiratory feedback reliably increased and decreased heart rate; subjects who controlled respiration with respiratory instructions only reliably increased but not decreased heart rate; subjects in the respiratory-feedback conditions showed higher heart-rate increase and decrease than heart-rate increase and decrease of subjects in the other six conditions.

Adult↗
PubMed1984

Differential effects of feedback sensitivity upon learned control of skin temperature.

Ninety subjects participated in a skin temperature biofeedback study concerning the effects of feedback sensitivity. Subjects were randomly assigned to a high sensitivity, low sensitivity, or a no-feedback condition. Based upon previous research, it was predicted that the low sensitivity condition would produce superior skin temperature warming and greater reduction of autonomic arousal. Also, it was predicted that both feedback conditions would be superior to the no-feedback condition for skin temperature control and reduction of autonomic arousal. The results indicated that low sensitivity feedback was not superior to high sensitivity feedback for skin temperature control, but did produce greater reduction of autonomic variables. The prediction that feedback was superior to no-feedback was also confirmed.

Adolescent↗
PubMed2001

Feedback effects on cost-benefit learning in perceptual categorization.

Two experiments were conducted in which the effects of different feedback displays on decision criterion learning were examined in a perceptual categorization task with unequal cost-benefits. In Experiment 1, immediate versus delayed feedback was combined factorially with objective versus optimal classifier feedback. Immediate versus delayed feedback had no effect. Performance improved significantly over blocks with optimal classifier feedback and remained relatively stable with objective feedback. Experiment 2 used a within-subjects design that allowed a test of model-based instantiations of the flat-maxima (von Winterfeldt & Edwards, 1982) and competition between reward and accuracy (Maddox & Bohil, 1998a) hypotheses in isolation and of a hybrid model that incorporated assumptions from both hypotheses. The model-based analyses indicated that the flat-maxima model provided a good description of early learning but that the assumptions of the hybrid model were necessary to account for later learning. An examination of the hybrid model parameters indicated that the emphasis placed on accuracy maximization generally declined with experience for optimal classifier feedback but remained high, and fairly constant for objective classifier feedback. Implications for cost-benefit training are discussed.

Adult↗
PubMed1991

[Effects of feedback and changing criterion on the control of skin temperature].

Effects of feedback and changing criterion procedure on the skin temperature control and cognitive events (motivation, perceived control of skin temperature, and sensations accompanied with autogenic training) during an autogenic training (AT) were examined. Fifteen male students, five of each, were assigned to either AT with feedback under a fixed criterion (AT-FC), AT with feedback under a changing criterion (AT-CC), or AT without feedback (AT-NF) groups. Subjects were asked to increase the temperature of the right index finger using the AT in 12 training sessions. The criterion of feedback was fixed in the AT-FC group while it was increased in the AT-CC group when the temperature had satisfied the criterion in the previous session. Feedback had no effect on the performance of skin temperature control. However, it functioned as a cue for the judgement of performance and weakened the feeling of heaviness of the limbs. Changing criterion improved the performance gradually and increased the perceived efficacy of AT. These results suggested that the arousal elicited by feedback stimuli might suppress the feedback effect, and that the criterion could control the pattern of skin temperature change.

Adolescent↗
PubMed2005

Effectiveness of repeated video feedback in the acquisition of a surgical technical skill.

BACKGROUND: Previously we evaluated the effectiveness of videotaped feedback as a teaching tool for surgical residents using 3 different core skills in the field of orthopedics. Our results revealed no significant differences in technical skill among surgical residents who were exposed to videotaped feedback and those who were not. Several limitations in the study were identified, including the presence of only a single exposure to videotaped feedback. In the present study we included repeated exposures to determine if skill acquisition was enhanced. METHODS: Thirty-three surgical residents were randomly assigned to receive either no videotaped feedback (control group) or repeated video feedback over 3 consecutive weekly practice sessions on a vascular anastomosis bench model. On the fourth week, vascular surgeons blinded to the 2 groups evaluated the residents on the same vascular anastomosis task using a global rating scale and technical checklist forms. RESULTS: Twenty-six (79%) of the residents participated. Independent t tests comparing the scores of each of the 2 different measures between the control group and repeated videotaped feedback group revealed no statistically significant differences. CONCLUSIONS: There was no significant difference in the performance of a vascular anastomosis in a bench-training model between residents who were exposed to video feedback over several practice sessions and those who received no video feedback.

Clinical Competence↗
PubMed1990

Feedback in myoelectric prostheses.

This article briefly reviews the history of the use of feedback in artificial limbs. It suggests that researchers have concentrated unduly upon the use of feedback to control prehensile force or joint angle and advocates a broader perspective. In that context, the article presents a comprehensive view of the need for feedback in myoelectric prostheses. The difficulties of designing transducers to meet the stringent demands of prosthetics applications are considered, and problems inherent in several alternatives are identified. Various means of conveying feedback information to the amputee are reviewed in some detail. The concept of feedback in control systems is introduced in the context of closed-loop control of a prosthesis. The surprisingly good performance of skilled users of myoelectric prostheses is noteworthy implying that the distinction between sensory and proprioceptive feedback may be somewhat artificial. By integrating these two feedback types a satisfactory feedback system may become an attainable goal.

Artificial Limbs↗
PubMed1991

Loss of glucocorticoid fast feedback in depression.

A rate-sensitive fast-feedback inhibition of stress-induced corticotropin secretion by glucocorticoids is well documented in rats. Studies in patients with Cushing's disease or adrenal insufficiency have also supported the existence of fast feedback in humans. However, few studies exist in normal healthy subjects or depressed patients. This study compared fast-feedback inhibition of beta-endorphin/beta-lipotropin secretion by hydrocortisone in 16 control subjects and 16 depressed patients. A fast-feedback effect of hydrocortisone on beta-endorphin/beta-lipotropin secretion during the hour of the hydrocortisone infusion was demonstrated in control subjects. Depressed patients demonstrated no increase in beta-endorphin/beta-lipotropin concentrations during the infusion. These data suggest a decreased sensitivity to glucocorticoid fast feedback in depressed patients and complement existing studies demonstrating decreased sensitivity to proportional feedback by dexamethasone in depressed patients. We believe the data presented herein are the first demonstration that abnormal feedback occurs at the level of the brain rather than pituitary in depressed patients.

Adrenocorticotropic Hormone↗
PubMed1984

Motivation to obtain self-relevant feedback in depressed college students.

Thirty depressed and 30 nondepressed college students completed a social judgment task. Students initially received either positive, negative, or no preliminary feedback and were told that they could obtain more extended feedback about their performance at a cost of $.20 for each unit of feedback. As predicted, depressed students were willing to relinquish a greater amount of money to obtain self-relevant feedback. Additionally, depressed and nondepressed Ss were more motivated to obtain additional feedback after they had received positive or no preliminary feedback than after they had received negative preliminary feedback. Results support Rehm's (1977) description of a heightened need for external reassurance among depressed persons.

Adult↗
PubMed2026

Providing Feedback on Previous Pain Scores Did Not Affect Weekly Pain Variability: A Cohort-Nested Randomised Study.

BACKGROUND: Spinal pain is one of the leading causes of disability worldwide and repeated symptom monitoring is increasingly used to capture its fluctuating nature. However, repeated pain assessments may be influenced by prior responses, potentially affecting longitudinal patterns of pain reporting. This study examined whether providing feedback on prior pain scores influenced within-person variability in weekly pain intensity ratings and retention over 60 weeks. METHODS: This randomised study evaluating a methodological feature of repeated pain assessment was embedded within a cohort of adults with spinal pain referred to an outpatient hospital clinic. Participants (n = 2448) were randomised 1:1 to weekly pain intensity ratings (0-10 numerical rating scale) either with feedback ('You answered [X] last week') or without feedback. Analyses included participants with ≥ 40% valid responses (n = 1883), of whom 948 received feedback and 935 did not. The primary outcome was within-person variability in pain intensity, quantified using the root mean square of successive differences. Secondary outcomes included additional fluctuation metrics and the number of weeks with missing responses. RESULTS: No meaningful between-group differences were observed for the primary outcome (mean difference -0.04 points [95% confidence interval -0.08 to 0.01]) or secondary outcomes, including retention rates. Sensitivity analyses yielded consistent findings. CONCLUSIONS: Providing participants with feedback on their previous pain score did not meaningfully influence within-person pain variability or retention during 60 weeks of weekly monitoring. These findings aid the interpretation of repeated longitudinal pain assessments by showing that the observed variability was robust to this specific study design. SIGNIFICANCE: This randomised study showed that providing participants with feedback on prior pain scores did not meaningfully alter weekly pain variability or retention during 60 weeks of longitudinal monitoring. These findings contribute to the interpretation of repeated longitudinal pain assessments in spinal pain research and suggest that weekly pain reporting patterns are robust to prior-pain feedback during long-term symptom monitoring.

Humans↗