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PubMedDate not supplied

Feedback seeking in children and adolescents: associations with self-perceptions, attachment representations, and depression.

Because the feedback children and adolescents receive is important to their development, 2 experimental studies were designed to examine children's (M = 12 years) and adolescents' (M = 17 years) active selection of the quality of feedback they wish to receive. In both studies evidence emerged that participants' self-perceptions influence their feedback seeking. Participants with positive self-perceptions sought more positive feedback than participants with negative self-perceptions and sought more positive feedback than expected by chance. Participants with negative self-perceptions lacked this tendency to seek positive feedback and sometimes sought less positive feedback than expected by chance. As expected, depression and attachment-related measures were also associated with participants' feedback seeking. Contributions of feedback-seeking patterns to stability and change in children's and adolescents' development are discussed.

Adolescent↗
PubMed1989

The effectiveness of immediate feedback during the objective structured clinical examination.

Using eight different physical examination or technical stations, 400 examinations were conducted to evaluate the effectiveness of immediate feedback during the Objective Structured Clinical Examination (OSCE). The test group comprised 50 medical students who underwent a standard 4-minute examination followed by 2 minutes of feedback. Immediately following feedback the students repeated an identical 4-minute examination scored by the same examiners. The control group consisted of 50 students from the same class who underwent an identical testing sequence, but instead of receiving feedback, they were instructed to continue their examinations for an additional 2 minutes before repeating the stations. Simple repetition of the task did not significantly improve score (mean increase 2.0%, NS). Extending the testing period from 4 to 6 minutes resulted in a small but significant increase in score (mean 6.7%, P less than 0.001). However, there was a much larger increase in the scores obtained following 2 minutes of immediate feedback compared to pre-feedback performance (mean 26.3%, P less than 0.0001). The majority of students and examiners felt that feedback, as administered in this study, was valuable both as a learning and teaching experience. Short periods of immediate feedback during an OSCE are practical and can improve competency in the performance of criterion-based tasks, at least over the short term. In addition, such feedback provides students with valuable self-assessment that may stimulate further learning.

Clinical Competence↗
PubMed2001

The dynamic characteristics of the feedback signal from horizontal cells to cones in the goldfish retina.

1. The dynamic properties of the microcircuitry formed by cones and horizontal cells in the isolated goldfish retina were studied. Cones project to horizontal cells and horizontal cells feed back to cones via a relatively slow negative feedback pathway. 2. The time constant of the feedback signal in cones and of the effect this feedback signal had on the responses of second-order neurons was determined using whole-cell patch clamp and intracellular recording techniques. 3. It was found that the feedback signal in cones had a time constant of around 80 ms, whereas the time constant of the effect this feedback signal had on the second-order neurons ranged from 36 to 116 ms. This range of time constants can be accounted for by the non-linearity of the Ca(2+) current in the cones. In depolarized cones, the feedback-mediated response in second-order neurons had a similar time constant to that of the direct light response of the cone, whereas in hyperpolarized cones, the time constant of the feedback-mediated response in second-order neurons was considerably larger. 4. Further, it was shown that there was no delay in the feedback pathway. This is in contrast to what has been deduced from the response properties of second-order neurons. In one type of horizontal cell, the responses to red light were delayed relative to the responses to green light. This delay in the second-order neurons can be accounted for by the interaction of the direct light response of the medium-wavelength-sensitive cones (M-cones) with the feedback response of the M-cones received from the horizontal cells.

Animals↗
PubMed2001

Effects of delayed auditory feedback (DAF) on the pitch-shift reflex.

Changes in voice pitch auditory feedback to vocalizing subjects elicit compensatory changes in voice fundamental frequency (F0). The neural mechanisms responsible for this behavior involve the auditory and vocal-motor systems, collectively known as the audio-vocal system. Previous work [Burnett et al., J. Acoust. Soc. Am. 103, 3153-3161 (1998); Hain et al., Exp. Brain Res. 130, 133-141 (2000); Larson et al., J. Acoust. Soc. Am. 107, 559-564 (2000)] indicated that this system operates using negative feedback to cancel out low-level errors in voice F0 output. By introducing delays in the auditory feedback pathway, we hoped to transiently "open" the feedback loop and learn which components of the response are most closely related to the timing of the auditory feedback signal. Subjects were presented with pitch-shift stimuli that were paired with a delay of 0, 50, 100, 200, 300, or 500 ms. Delayed auditory feedback did not affect voice F0 response latency or magnitude, but it delayed the timing of later parts of the response. As a further test of the audio-vocal control system, a second experiment was conducted in which delays of 100, 200, or 300 ms were combined with stimuli having onset velocities of 1000 or 330 cents/s. Results confirmed earlier reports that the system is sensitive to velocity of stimulus onset. A simple feedback model reproduced most features of both experiments. These results strongly support previous suggestions that the audio-vocal system monitors auditory feedback and, through closed-loop negative feedback incorporating a delay, adjusts voice F0 so as to cancel unintentional small magnitude fluctuations in F0.

Adolescent↗
PubMed2000

Randomised trial of monitoring, feedback, and management of care by telephone to improve treatment of depression in primary care.

OBJECTIVE: To test the effectiveness of two programmes to improve the treatment of acute depression in primary care. DESIGN: Randomised trial. SETTING: Primary care clinics in Seattle. PATIENTS: 613 patients starting antidepressant treatment. INTERVENTION: Patients were randomly assigned to continued usual care or one of two interventions: feedback only and feedback plus care management. Feedback only comprised feedback and algorithm based recommendations to doctors on the basis of data from computerised records of pharmacy and visits. Feedback plus care management included systematic follow up by telephone, sophisticated treatment recommendations, and practice support by a care manager. MAIN OUTCOME MEASURES: Blinded interviews by telephone 3 and 6 months after the initial prescription included a 20 item depression scale from the Hopkins symptom checklist and the structured clinical interview for the current DSM-IV depression module. Visits, antidepressant prescriptions, and overall use of health care were assessed from computerised records. RESULTS: Compared with usual care, feedback only had no significant effect on treatment received or patient outcomes. Patients receiving feedback plus care management had a higher probability of both receiving at least moderate doses of antidepressants (odds ratio 1.99, 95% confidence interval 1.23 to 3.22) and a 50% improvement in depression scores on the symptom checklist (2.22, 1.31 to 3.75), lower mean depression scores on the symptom checklist at follow up, and a lower probability of major depression at follow up (0.46, 0.24 to 0.86). The incremental cost of feedback plus care management was about $80 ( pound50) per patient. CONCLUSIONS: Monitoring and feedback to doctors yielded no significant benefits for patients in primary care starting antidepressant treatment. A programme of systematic follow up and care management by telephone, however, significantly improved outcomes at modest cost.

Acute Disease↗
PubMed2006

Does telling people what they have been doing change what they do? A systematic review of the effects of audit and feedback.

BACKGROUND: Many people advocate audit and feedback as a strategy for improving professional practice. The main results of an update of a Cochrane review on the effects of audit and feedback are reported. DATA SOURCES: The Cochrane Effective Practice and Organisation of Care Group's register up to January 2004 was searched. Randomised trials of audit and feedback that reported objectively measured professional practice in a healthcare setting or healthcare outcomes were included. REVIEW METHODS: Data were independently extracted and the quality of studies were assessed by two reviewers. Quantitative, visual and qualitative analyses were undertaken. MAIN RESULTS: 118 trials are included in the review. In the primary analysis, 88 comparisons from 72 studies were included that compared any intervention in which audit and feedback was a component to no intervention. For dichotomous outcomes, the median-adjusted risk difference of compliance with desired practice was 5% (interquartile range 3-11). For continuous outcomes, the median-adjusted percentage change relative to control was 16% (interquartile range 5-37). Low baseline compliance with recommended practice and higher intensity of audit and feedback appeared to predict the effectiveness of audit and feedback. CONCLUSIONS: Audit and feedback can be effective in improving professional practice. The effects are generally small to moderate. The absolute effects of audit and feedback are likely to be larger when baseline adherence to recommended practice is low and intensity of audit and feedback is high.

Education, Medical, Continuing↗
PubMed1992

Effect of changing feedback delay on spontaneous oscillations in smooth pursuit eye movements of monkeys.

1. Our goal was to discriminate between two classes of models for pursuit eye movements. The monkey's pursuit system and both classes of model exhibit oscillations around target velocity during tracking of ramp target motion. However, the mechanisms that determine the frequency of oscillations differ in the two classes of model. In "internal feedback" models, oscillations are controlled by internal feedback loops, and the frequency of oscillation does not depend strongly on the delay in visual feedback. In "image motion" models, oscillations are controlled by visual feedback, and the frequency of oscillation does depend on the delay in visual feedback. 2. We measured the frequency of oscillation during pursuit of ramp target motion as a function of the total delay for visual feedback. For the shortest feedback delays of approximately 70 ms, the frequency of oscillation was between 6 and 7 Hz. Increases in feedback delay caused decreases in the frequency of oscillation. The effect of increasing feedback delay was similar, whether the increases were produced naturally by dimming and decreasing the size of the tracking target or artificially with the computer. We conclude that the oscillations in eye velocity during pursuit of ramp target motion are controlled by visual inputs, as suggested by the image motion class of models. 3. Previous experiments had suggested that the visuomotor pathways for pursuit are unable to respond well to frequencies as high as the 6-7 Hz at which eye velocity oscillates in monkeys. We therefore tested the response to target vibration at an amplitude of +/- 8 degrees/s and frequencies as high as 15 Hz. For target vibration at 6 Hz, the gain of pursuit, defined as the amplitude of eye velocity divided by the amplitude of target velocity, was as high as 0.65. We conclude that the visuomotor pathways for pursuit are capable of processing image motion at high temporal frequencies. 4. The gain of pursuit was much larger when the target vibrated around a constant speed of 15 degrees/s than when it vibrated around a stationary position. This suggests that the pursuit pathways contain a switch that must be closed to allow the visuomotor pathways for pursuit to operate at their full gain. The switch apparently remains open for target vibration around a stationary position. 5. The responses to target vibration revealed a frequency at which eye velocity lagged target velocity by 180 degrees and at which one monkey showed a local peak in the gain of pursuit.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMedDate not supplied

Improving patient feedback about and outcomes with antidepressant treatment: a study in eight community pharmacies.

OBJECTIVE: To determine (1) whether telephone follow-up using a standardized telemonitoring tool can influence the nature and extent to which antidepressant users provide feedback to pharmacists, (2) whether patient characteristics are associated with the extent of patient feedback, and (3) how patient feedback affects subsequent outcomes after controlling for patient characteristics. DESIGN: Randomized, controlled, experimental design. SETTING: Eight Wisconsin community pharmacies within a large managed care organization. PATIENTS: 60 patients presenting new antidepressant prescriptions. INTERVENTIONS: Three monthly telephone calls from pharmacists providing structured education and monitoring. MAIN OUTCOME MEASURES: Frequency of patient feedback to pharmacists, antidepressant knowledge, beliefs, percentage of missed doses, depression symptom scores, and perceptions of progress. RESULTS: Compared with usual care patients (n=32), pharmacist-guided education and monitoring (PGEM) patients (n=28) provided significantly more feedback to pharmacists regarding different aspects of their antidepressant therapy even after controlling for patient characteristics. Regression results also showed that patient feedback was significantly associated with greater antidepressant knowledge, positive antidepressant beliefs, and perceptions of progress after 3 months. Patient feedback was unrelated to nonadherence and depressive symptoms. CONCLUSION: Structured education and monitoring by pharmacists significantly improves the level of patient feedback to pharmacists, and such feedback may help pharmacists identify and address their patients' misconceptions, concerns, and progress with antidepressant therapy.

Adult↗
PubMed1977

Dynamics and mechanics of corticosteroid feedback at the hypothalamus and anterior pituitary gland.

Corticosteroid feedback mechanisms were investigated at the hypothalamic level using the rat hypothalamus in vitro and the pituitary level using basal hypthalamic-lesioned rats. Both fast and delayed corticosteroid feedback effects were demonstrated at the level of the hypothalamus and pituitary gland with doses of corticosteroids within or near the physiological range. These two phases of feedback were separated temporally by a 'silent period' during which no feedback was apparent. Studies on the mechanism of action of corticosteroids at the hypothalamic level showed that the fast feedback mechanism acts by inhibition of release whilst the delayed feedback mechanism acts by inhibition of both synthesis and release. The fast feedback action of corticosterone does not appear to act by excitation of neuroinhibitory pathways since neither picrotoxin nor phentolamine prevented the feedback action of corticosteroids in vitro. Corticosterone inhibition of corticotrophin releasing factor release was overcome by depolarization of the membrane with K+ suggesting that the mechanism of action of the fast feedback of corticosteroids is by membrane stabilization.

Acetylcholine↗
PubMed1975

Effects of field-articulation and feedback on perception of intermediate visual-kinesthetic position.

High and low field-articulators were compared on the accuracy with which they could adjust a rod to intermediate visual-kinesthetic positions while blindfolded, under four sensory-feedback conditions. Independent groups of 10 Ss were given auditory, visual, kinesthetic, or no sensory feedback for 16 trials and then tested on 8 trials without sensory feedback. High field-articulators were significantly more accurate on the feedback trials for all sensory-feedback conditions but not in terms of mean absolute error. The mean constant error on the test trials was significantly lower for the high field-articulators on all feedback conditions except for visual feedback where the low field-articulator had a lower constant error. Both the high and low field-articulators became more accurate and learned more in judging visual-kinesthetic position when auditory feedback was given. Low field-articulators showed significant improvement in accuracy with kinesthetic feedback. The results supported the hypothesis that intermediate directions can be learned and supported previous perceptual research.

Adolescent↗
PubMed1999

Speaking speed effects on delayed auditory feedback disruption of speech fluency.

24 Italian medical students performed a task of verbal fluency. 12 students (the control group) receiving Normal Auditory Feedback and 12 students receiving Delayed Auditory Feedback (delay of 200 msec.) performed six trials in six different experimental settings: normal or increased speaking rate, and, for each condition, once with bilateral input of the auditory feedback, once to the right ear, and once to the left ear. At the normal speaking rate, the disruptive effect of delayed feedback was confirmed. As the speaking rate increased, the total number of errors increased within the control group but decreased within the group given delayed feedback, although the total number of errors was always greater for the latter. In addition, speech was more disrupted when the auditory input was returned to the right ear (left hemisphere) for all the different conditions: Normal and Delayed Auditory Feedback, normal and increased speaking rate. In particular, the left hemisphere was less resistant to the disruptive effect of the delayed feedback than the right hemisphere. From these results, we suggest that, when speaking more quickly, one uses more central mechanisms of movement programming (cortical-cerebellum-thalamus-cortical, cortical-corpus striatum-thalamus-cortical, and cortical-thalamus-cortical circuits), or attentional control (cortico-reticular-cortical circuits) than peripheral mechanisms (tactile, proprioceptive, and acoustic circuits). This may explain the decreased disruptive influence of delayed auditory feedback on speed, fluency, and quality at increased speaking rates. Hemispheric specialization processes, however, may explain the more pronounced susceptibility of the left hemisphere or the less pronounced susceptibility of the right hemisphere during the delayed feedback condition. In fact, the former processes phonemic, grammatical, and lexical features of words whilst the latter is competent in using metaphors and prosody in controlling the emotional aspects of language. Moreover, the right hemisphere is more active on attentional tasks.

Acoustic Stimulation↗
PubMed1996

Resistive eccentric exercise: effects of visual feedback on maximum moment of knee extensors and flexors.

One of the most important features of isokinetic dynamometry is the accurate assessment of muscular function. One of the main factors affecting the accuracy of isokinetic parameters during maximum activation efforts is visual feedback. The purpose of this study was the examination of the effects of visual feedback on maximum moment measurements of the knee extensors and flexors during isokinetic eccentric activations. Twenty-five males performed five maximal efforts at angular velocities of 30 degrees/sec and 150 degrees/sec with and without visual feedback on a Biodex dynamometer. Visual feedback was provided as real time display of the moment output. A three-factor analysis of variance test revealed significant differences between the moments recorded with visual feedback and the nonvisual feedback maximum moments of knee extensors and flexors at both speeds. The mean extension peak moments at 30 degrees/sec and 150 degrees/sec under visual feedback condition were approximately 7.2 and 6.4% higher than the nonvisual feedback moments, respectively. The increase for the knee flexor moment was 8.7 and 9% for slow and fast speeds, respectively. These findings suggest that visual feedback can improve maximum eccentric output and should be provided during assessment of maximum eccentric strength on an isokinetic dynamometer.

Adult↗
PubMed2004

The effect of visual and haptic feedback on computer-assisted needle insertion.

OBJECTIVE: We present a study evaluating the effects of visual and haptic feedback on human performance in a needle insertion task. MATERIALS AND METHODS: A one-degree-of-freedom needle insertion simulator with a three-layer tissue model (skin, fat and muscle) was used in perceptual experiments. The objective of the 14 subjects was to detect the puncture of each tissue layer using varying haptic and visual cues. Performance was measured by overshoot error-the distance traveled by the virtual needle after puncture. RESULTS: Without force feedback, real-time visual feedback reduced error by at least 87% in comparison to static image overlay. Force feedback, in comparison to no force feedback, reduced puncture overshoot by at least 52% when visual feedback was absent or limited to static image overlay. A combination of force and visual feedback improved performance, especially for tissues with low stiffness, by at least 43% with visual display of the needle position, and by at least 67% with visual display of layer deflection. CONCLUSION: Real-time image overlay significantly enhances controlled puncture during needle insertion. Force feedback may not be necessary except in circumstances where visual feedback is limited.

Adult↗
PubMed1976

Acute and reversible inhibition of tubuloglomerular feedback mediated afferent vasoconstriction by the calcium-antagonist verapamil.

UNLABELLED: In order to analyze the role of afferent vasomotor activity in mediating tubuloglomerular feedback response, we studied the effect of the intravenously applied Ca++ antagonist Verapamil on proximal stop flow pressure (SFP). In Wistar rats SFP was recorded continuously upstream of a solid paraffin block under either zero or 50 nl/min loop perfusion rate with artificial tubular fluid. The latter elicits maximal feedback response. Similar experiments were performed on heminephrectomized rats which are known to exhibit a highly sensitive feedback response. RESULTS: Verapamil given as a single dose (0.05-0.15 mg/kg b.w., i.v.) resulted in a transient decrease of mean arterial blood pressure of about 10 to 20 mmHg (1 to 3 min), SFP was unaltered during zero loop perfusion. Verapamil applied during a feedback stimulated SFP decrease (50 nl/min loop perfusion) caused restoration of normal SFP for 6 to 10 min indicating an acute and reversible interference of this drug with feedback regulation. Reversal of feedback response was complete in both groups of rats irrespective of the large difference in their feedback sensitivity. Thus: 1. The Ca++ antagonist is a complete inhibitor of feedback mediated SFP changes, 2. decreased SFP during high loop perfusion rate could be titrated back to normal by continuous infusion of Verapamil (dose 0.04 mg/kg-min), 3. Furthermore, feedback regulation of SFP could be prevented by infusion of the drug just prior to increasing loop perfusion rate.

Animals↗
PubMed1975

Feedback as a source of information and as a source of noise in absolute judgments of loudness.

Two experiments investigated the effects of feedback on absolute judgements of loudness. In Experiment 1, subjects received aceurate, unreliable, or no feedback. While feedback improved the information transmitted in judgments, it gave lower d' values than no feedback. These results were not compatible with a signal detection model with a noisy sensory stage and a decision stage with a fixed criterion, but suggested that criteria move in response to feedback and thus contribute judgmental noise to perceptual processes. Further confirmation for a variable criterion was obtained in Experiment 2, where reliability of feedback was held constant, but feedback was biased to favor some response alternatives more than others. Biased feedback shifted the positions of criteria, but also increased the inertia of some criteria in responding to feedback which caused changes in d'.

Auditory Perception↗
PubMed2003

Fear of feedback.

Nobody likes performance reviews. Subordinates are terrified they'll hear nothing but criticism. Bosses think their direct reports will respond to even the mildest criticism with anger or tears. The result? Everyone keeps quiet. That's unfortunate, because most people need help figuring out how to improve their performance and advance their careers. This fear of feedback doesn't come into play just during annual reviews. At least half the executives with whom the authors have worked never ask for feedback. Many expect the worst: heated arguments, even threats of dismissal. So rather than seek feedback, people try to guess what their bosses are thinking. Fears and assumptions about feedback often manifest themselves in psychologically maladaptive behaviors such as procrastination, denial, brooding, jealousy, and self-sabotage. But there's hope, say the authors. Those who learn adaptive techniques can free themselves from destructive responses. They'll be able to deal with feedback better if they acknowledge negative emotions, reframe fear and criticism constructively, develop realistic goals, create support systems, and reward themselves for achievements along the way. Once you've begun to alter your maladaptive behaviors, you can begin seeking regular feedback from your boss. The authors take you through four steps for doing just that: self-assessment, external assessment, absorbing the feedback, and taking action toward change. Organizations profit when employees ask for feedback and deal well with criticism. Once people begin to know how they are doing relative to management's priorities, their work becomes better aligned with organizational goals. What's more, they begin to transform a feedback-averse environment into a more honest and open one, in turn improving performance throughout the organization.

Adaptation, Psychological↗
PubMed1997

A polysynaptic feedback circuit in rat visual cortex.

Feedback connections from extrastriate cortex to primary visual cortex (V1) in the primate may provide "top-down" information that plays a role in visual attention and object recognition. Our work in a rodent model of corticocortical circuitry demonstrates that feedback pathways synapse preferentially with pyramidal cells in V1 () and favor excitation over inhibition in cortical microcircuits (). To investigate the polysynaptic circuits activated by feedback inputs, we studied chains of neurons postsynaptic to feedback connections using a combination of axonal tract tracing and anterograde degeneration. This approach enabled independent labeling of local collaterals of forward-projecting neurons in V1 and feedback connections from extrastriate lateromedial (LM) visual area to V1. Postsynaptic targets were identified in the electron microscope after retrograde transport of biotinylated dextran amine (BDA) to identify dendrites of forward-projecting neurons (i.e., from V1 to LM) and postembedding immunogold labeling to identify GABAergic interneurons. The results show that feedback connections provide strong monosynaptic input to forward-projecting neurons in V1. These neurons in turn make local connections that preferentially form synapses with other pyramidal cells ( approximately 97%), many of which were identified as forward-projecting neurons. This indicates that feedback pathways provide input directly to neurons which make the reciprocal forward connection, and that feedback-recipient forward-projecting neurons are strongly interconnected. The function of these excitatory networks within V1 may be to amplify feedback activity and provide a circuit for modulation of striate cortical activity by top-down influences.

Animals↗
PubMed2007

Effect of multisource feedback on resident communication skills and professionalism: a randomized controlled trial.

OBJECTIVE: To determine whether augmenting standard feedback on resident performance with a multisource feedback intervention improved pediatric resident communication skills and professionalism. DESIGN: Randomized controlled trial. SETTING: Children's Hospital Medical Center, Cincinnati, Ohio, from June 21, 2004, to July 7, 2005. PARTICIPANTS: Thirty-six first-year pediatric residents. INTERVENTIONS: Residents assigned to the multisource feedback group (n = 18) completed a self-assessment, received a feedback report about baseline parent and nurse evaluations, and participated in a tailored coaching session in addition to receiving standard feedback. Residents in the control group (n = 18) received standard feedback only. The control group and their residency directors were blinded to parent and nurse evaluations until the end of the study. MAIN OUTCOME MEASURES: Residents' specific communication skills and professional behaviors were rated by parents and nurses of pediatric patients. Both groups were evaluated at baseline and after 5 months. Scores were calculated on each item as percentage in the highest response category. RESULTS: Both groups had comparable baseline characteristics and ratings. Parent ratings increased for both groups. While parent ratings increased more for the multisource feedback group, differences between groups were not statistically significant. In contrast, nurse ratings increased for the multisource feedback group and decreased for the control group. The difference in change between groups was statistically significant for communicating effectively with the patient and family (35%; 95% confidence interval, 11.0%-58.0%), timeliness of completing tasks (30%; 95% confidence interval, 7.9%-53.0%), and demonstrating responsibility and accountability (26%; 95% confidence interval, 2.9%-49.0%). CONCLUSION: A multisource feedback intervention positively affected communication skills and professional behavior among pediatric residents.

Adult↗