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PubMed2005

Feedback interventions for college alcohol misuse: what, why and for whom?

In response to the persistent problem of college drinking, universities have instituted a range of alcohol intervention programs for students. Motivational feedback is one intervention that has garnered support in the literature and been adopted on college campuses. This article reviews published outcome studies that have utilized feedback as a major component of an alcohol intervention for college students. Overall, 11 of the 13 reviewed studies (77%) found a significant reduction in drinking as compared to a control or comparison group. While the studies varied widely in terms of population, follow-up period, and feedback content, it appears that feedback can be effective whether delivered by mail, the Internet, or via a face-to-face motivational interview. Feedback seems to change normative perceptions of drinking and may be more effective among students who drink for social reasons. The addition of a group or individual counseling session does not appear to increase the short-term impact of the feedback.

Alcohol-Related Disorders↗
PubMed2005

Altering asymmetric limb loading after hip arthroplasty using real-time dynamic feedback when walking.

OBJECTIVE: To evaluate a walking program incorporating real-time biofeedback to reduce asymmetric limb loading after total hip arthroplasty (THA). DESIGN: Within-subject clinical intervention. SETTING: Biomechanics laboratory. PARTICIPANTS: Volunteers were screened for confounding disorders that could affect their gait other than unilateral THA. Participants included 28 subjects who were evaluated a minimum of 2 months after surgery and ambulatory without assistive devices. INTERVENTIONS: THA subjects were assigned to a feedback, no-feedback, or control group. The feedback group walked on a treadmill 15 minutes, 3 times a week for 8 weeks while matching step-to-step reaction forces. Subjects walking without feedback had equal time. The control group did not train. MAIN OUTCOME MEASURES: Symmetry indices for peak limb-loading force, rate of rise of loading force, and impulse calculated from vertical foot-ground forces. Symmetry index changes were evaluated using 2-factor, repeated-measures analyses of variance with a Tukey post hoc test. RESULTS: Loading rate and impulse equalization improved for the feedback group (P<.01). Loading rate equalization improved for the no-feedback group (P=.01). There were no changes for the control group. CONCLUSIONS: This preliminary study suggests that a treadmill walking program may help persons with a THA achieve a more symmetric gait. Additional investigation of the potential benefits of a rehabilitation program incorporating treadmill walking with and without biofeedback is recommended.

Aged↗
PubMed2000

Social anxiety and self-impression: cognitive preparation enhances the beneficial effects of video feedback following a stressful social task.

Negative and distorted images of the observable self are important in the development and maintenance of social phobia. Previous research has shown that video feedback has potential to correct the distorted self-perception [Rapee, R. M. & Hayman, K. (1996). The effects of video feedback on the self-evaluation of performance in socially anxious subjects. Behaviour Research and Therapy, 34, 315-322]. The present experiment investigated whether the construction of a self-image prior to viewing the video may enhance the therapeutic effects of video feedback. High and low socially anxious individuals gave a speech and then viewed the video of their performance. Half of the sample were given cognitive preparation prior to viewing the video. Cognitive preparation involved asking participants to (1) predict in detail what they will see in the video, (2) form an image of themselves giving the speech and (3) watch the video as though they were watching a stranger. Participants who received cognitive preparation prior to the video feedback made higher ratings of their overall performance and of specific aspects of their performance compared to those who were not given cognitive preparation and compared to the same ratings made prior to the video feedback. These results suggest that the therapeutic effects of video feedback can be enhanced by careful cognitive preparation which maximises the perceived discrepancy between self and video images.

Adolescent↗
PubMed1999

Evaluation, feedback, and remediation in anesthesiology residency training: a survey of 124 United States programs.

STUDY OBJECTIVE: To provide a review of evaluation, feedback, and remediation methods in United States residency programs during 1995 to 1996. The information gathered is to serve as a framework for discussions within and among programs regarding ways to enhance their current processes of evaluation, feedback, and remediation, and to serve as a baseline for future assessments. DESIGN, SETTING AND SUBJECTS: A three-page survey was mailed to program directors of each of the 145 anesthesiology programs listed in the Accreditation Council for Graduate Medical Education (ACGME/NRMP) Directory. MEASUREMENTS AND MAIN RESULTS: Quantitative and qualitative responses were sought about the resident evaluation process (including techniques of gathering information, frequency of evaluations, faculty compliance, and modes of offering feedback), departmental clinical competence committee, probation and remediation policies for problem residents, and the use of formal examinations. There was an 85.5% response rate. Frequency of evaluation of residents ranged from daily to quarterly: evaluations used both narrative comments and rating scales in 89% of institutions. Faculty compliance in the evaluation process was greater than 75% in 45.1% of programs. Only 25 (20.2%) programs offered formal training about resident evaluation to their faculty. Clinical competence committee meetings averaged five times annually. Ninety-five percent of committees were chaired by someone other than the department chairperson and 27% had resident members. A written policy regarding problem residents was used by 67.7% of programs, a formal probation policy by 82.2%. Standardized tests to provide feedback and guidance to residents existed in 48.3% of programs. CONCLUSIONS: There is a tremendous variety of techniques and methodologies employed among anesthesiology residency programs with regard to evaluation, feedback, and remediation, within the framework of the ACGME guidelines. Faculty training in the assessment of and feedback to residents is one area in which many programs can begin to strengthen their current procedures.

Accreditation↗
PubMed1999

Abnormal response to negative feedback in depression.

BACKGROUND: Recent studies have suggested that subjects with depression suffer a diagnosis-specific motivational deficit, characterized by an abnormal response to negative feedback that endures beyond clinical recovery. Furthermore, it has been suggested that negative feedback may motivate non-depressed controls, but not depressed patients, to improve their performance in neuropsychological tests. METHODS: We describe two studies. The first compared performance on the simultaneous and delayed match to sample (SDMS) task from the CANTAB neuropsychological test battery, in 20 patients with severe depression with 20 with acute schizophrenia, 40 with chronic schizophrenia and 40 healthy controls. The second examined the performance of depressed patients with diurnal variation in symptoms and cognitive function. RESULTS: All patients groups showed impairments on the simultaneous and delayed match to sample task compared to controls. Depressed patients did not show an abnormal response to negative feedback. Controls did not show a motivational effect of negative feedback. Depressed patients with diurnal variation showed no variation in their response to perceived failure. There was no evidence of abnormal response to negative feedback in any patient group using the 'runs test' or of a motivational effect in controls. Conditional probability analysis was not independent of the total number of errors made in the SDMS task. CONCLUSIONS: Further studies are suggested to examine whether an abnormal response to negative feedback characterizes particular subgroups of patients suffering from depression.

Acute Disease↗
PubMed1995

Modification of dysfunctional patterns of sexual response through autonomic arousal and false physiological feedback.

Effects of autonomic arousal and positive-false vaginal blood volume (VBV) feedback were examined to identify how cognitive and physiological mechanisms mediate sexual arousal, and can be modified to reverse dysfunctional processes. Sixty-four matched sexually dysfunctional women were randomly assigned to 4 conditions: autonomic arousal-evoking or neutral-control preexposure film stimulus paired with an erotic stimulus, and positive-false VBV feedback or no feedback. Results revealed the following: (a) general autonomic arousal enhanced genital arousal; false feedback increased (b) expectations of sexual arousal, (c) actual vasocongestive response, and (d) the subsequent experience of sexual arousal; (e) heightened expectations with false feedback were followed by an increase in actual genital response within 30 s, and (f) the combined effects of autonomic arousal and false feedback enhanced expectations and subsequent genital arousal to levels comparable with those of sexually functional women (E.M. Palace & B.B. Gorzalka, 1990) within 3 min.

Adult↗
PubMed2002

Creating a positive experience of research for people with psychiatric disabilities by sharing feedback.

This paper describes a consumer evaluation that explored the reflections of persons with psychiatric disabilities on receiving individualized feedback following participation in a community research project. Findings indicate that feedback is an important element of research, offering a valued means to reciprocate participants' contributions. Feedback can facilitate mutual learning, fostering hope and empowerment, while participation in performance tests without feedback may reinforce negative self-evaluations. Feedback needs sensitive presentation and discussion, focused on strengths, to be experienced as worthwhile and respectful by people with psychiatric disabilities. This is particularly important as their self-identities may already be undermined by experiences of mental illness. Researchers need dedicated time, resources, and training to incorporate individual feedback in research.

Australia↗
PubMed2003

Interactive faculty development seminars improve the quality of written feedback in ambulatory teaching.

We performed a pre-post study of the impact of three 90-minute faculty development workshops on written feedback from encounters during an ambulatory internal medicine clerkship. We coded 47 encounters before and 43 after the workshops, involving 9 preceptors and 44 third-year students, using qualitative and semiquantitative methods. Postworkshop, the mean number of feedback statements increased from 2.8 to 3.6 statements (P =.06); specific (P =.04), formative (P =.03), and student skills feedback (P =.01) increased, but attitudinal (P =.13) and corrective feedback did not (P =.41). Brief, interactive, faculty development workshops may refine written feedback, resulting in more formative specific written feedback comments.

Ambulatory Care↗
PubMed1983

Rapid visual feedback processing in single-aiming movements.

A major line of behavioral support for motor-program theory derives from evidence indicating that feedback does not influence the execution and control of limited duration movements. Since feedback cannot be utilized, the motor-program is assumed to act as the controlling agent. in a classic study, Keele and Posner observed that visual feedback had no effect on the accuracy of 190-msec single-aiming movements. Therefore visual feedback processing time is greater than 190 msec, and, more importantly, limited duration movements are governed by motor programs. In the present paper, we observed that visual feedback can affect the spatial accuracy of movement with durations much less than 190 msec. We hypothesize that visual feedback can aid motor control via processes not associated with intermittent error corrections.

Journal Article↗
PubMed1991

Methodology for motor learning: a paradigm for kinematic feedback.

Knowledge of results (KR)--information feedback about goal achievement--has been one of the most extensively examined variables in motor learning. In most natural movement learning situations, however, instructors more common]y provide augmented information regarding various kinematic or kinetic aspects of the movement pattern itself (sometimes termed knowledge of performance, KP). But despite the inherent interest in kinematic feedback, several factors reviewed here have operated to inhibit its study, the most important of which has been the lack of a suitable laboratory task and paradigm. The limitations of earlier paradigms have concerned (a) the use of overly simple motor behaviors, probably to minimize the problems in kinematic measurement, (b) the tendency for the environmental goal or the task to be isomorphic with the kinematic pattern, and (c) thc failure to use transfer or retention tests as measures of learning effects of the feedback manipulations. In this article, we describe our efforts to create a new paradigm for kinematic feedback, the rationale for its development, and the details of its operation. Finally, we provide evidence that the task and paradigm are sensitive to manipulations of kinematic feedback, providing some assurance that the paradigm can potentially answer future research questions about the role of kinematic feedback for learning.

Journal Article↗
PubMed2000

Stress reactivity after maximal exercise: the effect of manipulated performance feedback in endurance athletes.

This study was designed to assess the effect of performance feedback on stress reactivity after recovery from maximal exercise. Forty competitive athletes were recruited to complete a maximal exercise test. Performance feedback was manipulated after the exercise test to give four groups: (1) high performance, (2) low performance, (3) accurate feedback and (4) no exercise control. Cardiovascular reactivity was assessed during psychological stress. The results indicate that accurate feedback participants experienced lower relative reactivity to stress (lower mean arterial pressure) than their no-exercise counterparts. These results demonstrate that the stress-buffering effect of exercise extends to maximal exercise. In addition, high-performance participants experienced lower relative reactivity than low-performance participants. Thus, low-performance feedback was sufficient to remove the buffering effect of exercise. There were no differences between the high-performance and accurate feedback conditions, or between the low-performance and control conditions.

Adolescent↗
PubMed1991

Entrainment of Syrian hamsters to short photoperiod T-cycles does not reverse the inhibitory nature of feedback lighting on the photoperiodic response.

Experiments examining the photoperiodic effects of various light-dark cycles unexpectedly demonstrated that light during the subjective night is not necessarily photoinductive to the reproductive system of long day breeders. Feedback lighting (illumination in response to locomotor activity) and a high-frequency light-dark cycle with 1 minute (m) of light followed with 1 minute of dark (LD1m:1m) failed to maintain reproductive function in Syrian hamsters despite exposing the animal to 5-6 hours of light per cycle during the subjective night. In an effort to determine why feedback lighting and LD1m:1m do not maintain reproductive function, male Syrian hamsters were exposed to one of the following lighting conditions for ten weeks: a light-dark cycle with 14 hours of light followed by a 10 hour light-dark cycle of 1 minute of light followed by 1 minute of dark ¿LD14:10(1m:1m)¿; a cycle of a 14 hour light-dark cycle of 1 minute of light followed by 1 minute of dark, followed by 10 hours of dark ¿LD14(1m:1m):10)¿; a light-dark cycle of 2 hours of light and 21 hours of dark (LD2:21); a light-dark cycle of 2 hours of light and 22 hours of dark (LD2:22); LD2:21 in conjunction with feedback lighting (LD2:21/FB); LD2:22 in conjunction with feedback lighting (LD2:22/FB); constant dark (DD) or constant light (LL). All hamsters exposed to LD14(1m:1m):10 entrained. Only 7 of 12 hamsters exposed to LD14:10(1m:1m) entrained. This supports previous findings, which suggest that the circadian system has difficulty differentiating between LD1m:1m and LL. Exposure to LD2:22 and DD induced testicular regression, while LL, LD2:21 and LD14(1m:1m):10 maintained reproductive function, as expected. The addition of approximately 5 hours of nocturnal illumination by feedback lighting, however, not only failed to prevent reproductive regression in LD2:22, but attenuated the stimulatory nature of LD2:21. This suggests that feedback lighting is not only not stimulatory, but may be actively inhibitory. Perhaps this is due to a photoinhibitory effect of multitransitional nocturnal illumination. This hypothesis is supported by the finding that LD14:10(1m:1m) allows regression, while LD14(1m:1m):10 is stimulatory. These findings also imply that the state of the circadian system is instrumental in the reproductive system's interpretation of a light signal.

Activity Cycles↗
PubMed2006

Effects of visual feedback therapy on postural control in bilateral standing after stroke: a systematic review.

OBJECTIVE: To establish whether bilateral standing with visual feedback therapy after stroke improves postural control compared with conventional therapy and to evaluate the generalization of the effects of visual feedback therapy on gait and gait-related activities. DESIGN: A systematic review. METHODS: A computer-aided literature search was performed. Randomized controlled trials and controlled clinical trials, comparing visual feedback therapy with conventional balance treatments were included up to April 2005. The methodological quality of each study was assessed with the the Physiotherapy Evidence Database scale. Depending on existing heterogeneity, studies with a common variable of outcome were pooled by calculating the summary effect-sizes using fixed or random effects models. RESULTS: Eight out of 78 studies, presenting 214 subjects, were included for qualitative and quantitative analysis. The methodological quality ranged from 3 to 6 points. The meta-analysis demonstrated non-significant summary effect-sizes in favour of visual feedback therapy for weight distribution and postural sway, as well as balance and gait performance, and gait speed. CONCLUSION: The additional value of visual feedback therapy in bilateral standing compared with conventional therapy shows no statistically significant effects on symmetry of weight distribution between paretic and non-paretic leg, postural sway in bilateral standing, gait and gait-related activities. Visual feedback therapy should not be favoured over conventional therapy. The question remains as to exactly how asymmetry in weight distribution while standing is related to balance control in patients with stroke.

Adult↗
PubMed1993

The effects of auditory feedback from the nucleus cochlear implant on the vowel formant frequencies produced by children and adults.

Cochlear implants provide an auditory signal with which profoundly deaf users may monitor their own speech production. The vowel production of two adults and three children who used the Nucleus multiple-electrode cochlear implant was examined to assess the effect of altered auditory feedback. Productions of words were recorded under conditions where the talkers received auditory feedback (speech processor turned on) and where no auditory feedback was provided (speech processor turned off). Data were collected over 3 days at weekly intervals. First and second formant frequencies were measured and the data were analysed to assess significant differences between auditory feedback conditions, vowel context, and data collection points. Overall, the results varied across talkers, across the data collection days, and depended on the consonant environment of the vowel. However, two effects of auditory feedback were noted. First, there was a generalized shift in first formant frequencies between the processor on and processor off conditions across three of the five subjects, but the shift differed in direction for each subject. Second, for three of the five talkers, the two front vowels /epsilon/ and /i/ were more neutralised in the absence of auditory feedback. However, this effect was less pronounced than that noted by previous studies.

Aged↗
PubMedDate not supplied

Estimating one's own systolic blood pressure: effects of feedback training.

This study was aimed at discovering the ability of subjects to estimate absolute levels of systolic blood pressure after feedback of daily blood pressure information. Twenty-one subjects were studied who had shown a variation of at least +/- 20 mm Hg in systolic pressure during 8 days of base-line measurements. Subjects' estimates were found to be moderately accurate even before any specific blood pressure information feedback was given (mean error was +/- 12.4 mm Hg). Then during 15 days of information feedback, subjects' accuracy improved, e.g., for 10 subjects who were given correct information feedback the mean error was +/- 7.4 mm Hg, a highly significant improvement. This is a high degree of accuracy-especially in comparison with the mean variation of +/- 5.8 mm Hg from 1 min to the next in their systolic blood pressure. The learning of one's range of blood pressures appeared to be the principal component of the improvement. Range information had been provided by giving the subject his range of fluctuation for the 8-day base-line period, and by daily blood pressure information feedback immediately after each estimate. Two types of estimators were distinguished: Those who were relatively accurate versus those who were inaccurate in estimating at their own extremes of blood pressure. Those who were inaccurate at their own extremes (1) paid less attention to the feedback of information they were provided with as well as to the internal cues from their own blood pressure and (2) were more field independent.

Attention↗
PubMed2004

Control of Turing pattern formation by delayed feedback.

The effect of the global delayed feedback technique on Turing pattern formation is investigated in the modified Lengyel-Epstein two-variable model. Feedback intensity, delay time, and feedback-imposing time (the period of time that feedback is present in the system) are all found to be of significant influence on Turing pattern formation time. Under appropriate parameter settings, delayed feedback could suppress or induce the Turing pattern if the feedback intensity is strong enough.

Journal Article↗
PubMed2005

Advanced information feedback in intelligent traffic systems.

The optimal information feedback is very important to many socioeconomic systems like stock market and traffic systems aiming to make full use of resources. As to traffic flow, a reasonable real-time information feedback can improve the urban traffic condition by providing route guidance. In this paper, the influence of a feedback strategy named congestion coefficient feedback strategy is introduced, based on a two-route scenario in which dynamic information can be generated and displayed on the board to guide road users to make a choice. Simulation results adopting this optimal information feedback strategy have demonstrated high efficiency in controlling spatial distribution of traffic patterns compared with the other two information feedback strategies, i.e., travel time and mean velocity.

Journal Article↗
PubMed1989

Stromal Phosphate Concentration Is Low during Feedback Limited Photosynthesis.

It has been hypothesized that photosynthesis can be feedback limited when the phosphate concentration cannot be both low enough to allow starch and sucrose synthesis at the required rate and high enough for ATP synthesis at the required rate. We have measured the concentration of phosphate in the stroma and cytosol of leaves held under feedback conditions. We used non-aqueous fractionation techniques with freeze-clamped leaves of Phaseolus vulgaris plants grown on reduced phosphate nutrition. Feedback was induced by holding leaves in low O(2) or high CO(2) partial pressure. We found 7 millimolar phosphate in the stroma of leaves in normal oxygen but just 2.7 millimolar phosphate in leaves held in low oxygen. Because 1 to 2 millimolar phosphate in the stroma may be metabolically inactive, we estimate that in low oxygen, the metabolically active pool of phosphate is between negligible and 1.7 millimolar. We conclude that halfway between these extremes, 0.85 millimolar is a good estimate of the phosphate concentration in the stroma of feedback-limited leaves and that the true concentration could be even lower. The stromal phosphate concentration was also low when leaves were held in high CO(2), which also induces feedback-limited photosynthesis, indicating that the effect is related to feedback limitation, not to low oxygen per se. We conclude that the concentration of phosphate in the stroma is usually in excess and that it is sequestered to regulate photosynthesis, especially starch synthesis. The capacity for this regulation is limited by the coupling factor requirement for phosphate.

Journal Article↗