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PubMed1978

The influence of videotape feedback on the self-assessments of psychiatric patients.

The effects of videotape feedback on patients' self-perception were assessed in a study which was a partial replication of an investigation reported by Griffiths and Hinkson (1973). Subjects were randomly allocated to one of three groups. After a semi-structured interview, they were either (1) shown a videotape of the interview, or (2) shown a videotape of another person being interviewed, or (3) engaged in other activities not involving videotape. Patients' self-ratings indicated that videotape feedback has immediate effects on self-assessments of social ease and physical attractiveness. Feedback produced changes in ratings of social ease, but individuals differed in the direction of the change (i.e. whether social ease was "better" or "worse"). The direction of the change was predicted by a questionnaire measure of response style. Feedback also tended to make patients rate themselves as less attractive in the eyes of other people. All changes were, however, temporary and had disappeared at a two-week follow-up. The results are generally consistent with those reported by Griffiths and Hinkson in that they indicate temporary and specific changes in response to videotape feedback. The implications of the results are discussed.

Adolescent↗

PubMed2004

Feedback.

The emergency department provides a rich environment for diverse patient encounters, rapid clinical decision making, and opportunities to hone procedural skills. Well-prepared faculty can utilize this environment to teach residents and medical students and gain institutional recognition for their incomparable role and teamwork. Giving effective feedback is an essential skill for all teaching faculty. Feedback is ongoing appraisal of performance based on direct observation aimed at changing or sustaining a behavior. Tips from the literature and the author's experience are reviewed to provide formats for feedback, review of objectives, and elements of professionalism and how to deal with poorly performing students. Although the following examples pertain to medical student education, these techniques are applicable to the education of all adult learners, including residents and colleagues. Specific examples of redirection and reflection are offered, and pitfalls are reviewed. Suggestions for streamlining verbal and written feedback and obtaining feedback from others in a fast-paced environment are given. Ideas for further individual and group faculty development are presented.

Clinical Clerkship↗

PubMed2005

Fetal programming: excess prenatal testosterone reduces postnatal luteinizing hormone, but not follicle-stimulating hormone responsiveness, to estradiol negative feedback in the female.

Exposure of female sheep fetuses to excess testosterone (T) during early to midgestation produces postnatal hypergonadotropism manifest as a selective increase in LH. This hypergonadotropism may result from reduced sensitivity to estradiol (E2) negative feedback and/or increased pituitary sensitivity to GnRH. We tested the hypothesis that excess T before birth reduces responsiveness of LH and FSH to E2 negative feedback after birth. Pregnant ewes were treated with T propionate (100 mg/kg in cotton seed oil) or vehicle twice weekly from d 30-90 gestation. Responsiveness to E2 negative feedback was assessed at 12 and 24 wk of age in the ovary-intact female offspring. Our experimental strategy was first to arrest follicular growth and reduce endogenous E2 by administering the GnRH antagonist (GnRH-A), Nal-Glu (50 microg/kg sc every 12 h for 72 h), and then provide a fixed amount of exogenous E2 via an implant. Blood samples were obtained every 20 min at 12 wk and every 10 min at 24 wk before treatment, during and after GnRH-A treatment both before and after E2 implant. GnRH-A ablated LH pulsatility, reduced FSH by approximately 25%, and E2 production diminished to near detection limit of assay at both ages in both groups. Prenatal T treatment produced a precocious and selective reduction in responsiveness of LH but not FSH to E2 negative feedback, which was manifest mainly at the level of LH/GnRH pulse frequency. Collectively, these findings support the hypothesis that prenatal exposure to excess T decreases postnatal responsiveness to E2 inhibitory feedback of LH/GnRH secretion to contribute to the development of hypergonadotropism.

Animals↗

PubMed2005

Gender modulates sequential suppression and recovery of pulsatile growth hormone secretion by physiological feedback signals in young adults.

The basic mechanisms that drive the renewal of GH pulses in the human are not understood. Recent ensemble models predict that pulse regeneration requires quenching of an ongoing GH pulse by somatostatin outflow and evocation of a new burst by rebound GHRH release. We reasoned that related principles might explain why women consistently maintain higher-amplitude GH secretory bursts than men. Accordingly, the present study tests the hypothesis that gender modulates the successive dynamics of GH feedback and escape in the morning fasting, when GH pulses are larger in women. To this end, we infused single iv pulses of recombinant human (rh) GH (0, 1, and 3 microg/kg) in eight young men and six women on separate randomly ordered mornings fasting and quantitated serial inhibition and recovery of GH secretion by frequent sampling, immunochemiluminometry, a deconvolution procedure, and regularity analysis. Statistical contrasts revealed gender-comparable peak concentrations and kinetics of rhGH. However, women differed from men by way of: (1) 3.5- and 4.0-fold less feedback suppression of GH secretory-burst mass; (2) more irregular patterns of GH release during negative feedback; and (3) 12-and 14-fold greater postnadir rebound-like GH secretion after rhGH pulses. Mechanistic analyses based on a minimal feedback construct predicted that women generate higher endogenous secretagogue stimulation per unit somatostatin outflow than men. In summary, negative feedback induced by near-physiological GH pulses unmasks prominent gender-related contrasts in hypothalamo-pituitary autoregulation in young adults. A frugal but sufficient explanation of the ensemble outcomes is that women sustain greater hypothalamo-pituitary agonist input than men.

Adult↗

PubMed1983

Suppression of the positive feedback of estradiol benzoate on gonadotropin secretion by an inhibitory analog of luteinizing hormone-releasing hormone (LRH) in oophorectomized rhesus monkeys: evidence for a necessary synergism between LRH and estrogens.

Estrogens have a biphasic effect on gonadotropin (FSH and LH) secretion in human and nonhuman primates. Recent studies suggest that estrogens induce negative as well as positive feedback on gonadotropin secretion by a direct action at the pituitary gland. To further investigate the mechanism by which estrogens modulate gonadotropin secretion, the following experiments were performed. Oophorectomized rhesus monkeys were injected with estradiol benzoate (EB) at a dose of 40 micrograms/kg sc at zero time (controls). Three groups of animals received, additionally, an inhibitory analog of LRH, [Ac-D-p-Cl-Phe1,2, D-Trp3,D-Arg6,D-Ala10]LRH (200 micrograms, sc, daily) at 1) -48 to 48 h, 2) 0-48 h, and 3) 24-48 h from EB treatment, respectively. Blood was collected at -72, -48, -24, and 0 h, every 6 h from 6-84 h, and 96 and 116 h after EB; FSH and LH levels were measured by RIA. Control animals had a 70-80% decrease in baseline FSH and LH levels during the first 24 h after EB injection, followed by a sharp rise to 60-80% above basal levels 42-48 h post-EB. In contrast, animals that received the inhibitory analog of LRH in different regimens had more pronounced and prolonged negative feedback of EB on gonadotropin concentrations. The positive feedback release of FSH and LH was significantly diminished or delayed compared to control values. The results of this study indicate that this inhibitory analog of LRH potentiates the negative feedback and suppresses the positive feedback of EB on gonadotropins, suggesting that estrogens induce the secretion of FSH and LH through a mechanism that involves the action of LRH at the gonadotroph.

Animals↗

PubMed1985

Effects of sex steroids on the positive estrogen feedback mechanism in intact women and castrate men.

We studied the effects of prolonged testosterone treatment on ovulatory function and positive estrogen feedback in women and of prolonged estrogen priming on gonadotropin feedback in castrate men. An estrogen provocation test was carried out in 4 groups of transsexual subjects: 12 female transsexuals in their early follicular phase (days 3-5; group 1A), 8 females who had been treated with Depo-testosterone (T) for 3-6 months (group 1B), 11 men who had been castrated 3 months previously (group 2A), and 4 male castrates treated with oral estrogen for 3 months starting 3 months after castration (group 2B). The estrogen provocation test consisted of 3 GnRH tests (100 micrograms) carried out immediately before (0 h) and 44 and 92 h after an im injection of estradiol valerate (10 mg). Responses to the estrogen provocation test in women with normal menstrual cycles (group 1A) were typically female. After initial suppression at 44 h, a LH surge (positive feedback) occurred at 92 h. Pituitary responsiveness, however, was amplified both at 44 and 92 h. Prolonged T priming of women in group 1B did not inhibit the estrogen-induced LH surge, nor was the amplitude of the surge blunted. Removal of androgens and other testicular factors (group 2A) did not result in the appearance of an estrogen-induced LH surge. On the other hand, prolonged estrogen priming in male castrates (group 2B) resulted in activation of the positive feedback mechanism; a LH surge in response to the estrogen provocation occurred. The results of the present study imply that 1) contrary to an earlier suggestion, testosterone does not block or blunt the LH surge, indicating that it is probably not responsible for suppressing the LH surge in normal men; 2) testosterone can cause ovulatory failure without suppressing the LH surge in women; and 3) prolonged estrogen priming may be involved in activation of the positive feedback mechanism in humans.

Adult↗

PubMed1997

Specific linkages among luteinizing hormone, follicle-stimulating hormone, and testosterone release in the peripheral blood and human spermatic vein: evidence for both positive (feed-forward) and negative (feedback) within-axis regulation.

We have investigated possible (negative) feedback and (positive) feed-forward activity within the human male gonadotropic axis by measuring serum concentrations of LH, FSH, and testosterone in blood sampled frequently and for a prolonged interval (every 20 min for 19 h) simultaneously from the peripheral circulation and the left spermatic vein. Cross-correlation analysis with time lag was used to evaluate relationships among serial serum LH, FSH, and/or testosterone concentrations over time (i.e. consistency or dissociation of trends in concentrations). Separately, Cluster analysis was applied to identify discrete LH, FSH, and testosterone pulses, which were cataloged for possible peak coincidence. The hypergeometric probability distribution was then used to test the null hypothesis that LH, FSH, and testosterone pulses are randomly associated. Cross-correlation analysis revealed: 1) peripheral blood LH and testosterone concentrations correlate positively at lags of 40-120 min with LH increases preceding testosterone increases, viz., feed-forward (P < 0.001); 2) LH and FSH concentrations in peripheral blood are positively correlated in simultaneous blood samples, as well as when FSH lags LH by 20 min (P < 0.01); 3) unexpectedly, LH and FSH concentrations in peripheral blood are inversely related at a lag of 80-100 min (P = 0.002) and 0.004, respectively) where LH lags FSH; 4) LH and testosterone concentrations in the spermatic vein show strongly positive correlations at lags of 80, 100, and 120 min (P = 0.002, 0.004, and 0.021, respectively); 5) spermatic vein testosterone concentrations correlate negatively with peripheral blood LH concentrations 20 or 40 min later (P = 0.012 and 0.05, respectively), which indicates autonegative feedback; and 6) in contrast, testosterone levels in the spermatic vein correlate negatively with FSH values in the periphery 100 and 120 min later (P < 0.01), indicating more delayed negative feedback of testosterone on serum FSH concentrations. Discrete pulse coincidence analysis disclosed: 1) a total of 30 testosterone pulses in the spermatic vein and 25 testosterone pulses in peripheral blood, with 28 LH and 29 FSH pulses in the periphery; 2) individual LH and FSH peak concordance was significantly nonrandom for FSH pulse maxima lagging LH pulse maxima by 20 min (P < 0.05 vs. randomness), with 6 observed coincidences vs. 2.9 +/- 1.5 (SD) expected; 3) peripheral LH pulses and spermatic vein testosterone pulses were strongly nonrandomly coupled at an 80-min lag, with 8 events observed vs. 3.0 +/- 1.5 events expected (P = 0.004); and 4) LH peaks in peripheral blood followed testosterone peaks in the spermatic vein by 40 min in a nonrandom manner, specifically, n = 11 observed vs. 3.0 +/- 1.5 expected (P < 0.001), indicating possible LH escape from testosterone's negative feedback. In summary, physiological regulation of the human male LH, FSH, and testosterone axis comprises multidirectional interactions, consisting of both (positive) feed-forward and (negative) feedback coupling. Based on a concept of network integration, we propose that age and other pathophysiological factors might modulate and/or disrupt these dynamic within-axis multihormonal linkages.

Adolescent↗

PubMed2001

Differential regulation of gonadotropin secretion by testosterone in the human male: absence of a negative feedback effect of testosterone on follicle-stimulating hormone secretion.

Studies of sex steroid regulation of gonadotropin secretion in the human male have focused primarily on the respective site(s) of negative feedback of testosterone (T) and estradiol (E(2)). The use of pharmacological doses of sex steroids in these studies has precluded conclusions about the relative roles of T and E(2) in gonadotropin feedback. Thus, the aims of the present study were to 1) determine the relative contributions of T vs. E(2) to the sex steroid component of gonadotropin regulation, and 2) distinguish the feedback effects of T that that are direct (i.e. mediated by the androgen receptor) vs. indirect (mediated by aromatization to E(2)). Two experimental interventions were used: 1) inhibition of aromatization by a selective aromatase inhibitor to examine the impact of selective E(2) withdrawal; and 2) acute medical castration to examine the effect of ablating both T and E(2). Sixteen normal (NL) men (mean age, 30.5 +/- 2.2 yr) were studied. Nine NL subjects were treated with the aromatase inhibitor, anastrozole (10 mg, orally, daily, for 5 days). Twelve NL men underwent medical castration with ketoconazole (1-g loading dose followed by 400 mg, orally, four times a day for 5 days). Ketoconazole-treated subjects received concomitant treatment with dexamethasone (0.5 mg twice daily) to prevent the development of adrenal insufficiency. Single blood samples were drawn daily between 0800-1000 h. To ensure that dexamethasone was not altering the gonadotropin response to sex steroid ablation by a direct pituitary effect, five GnRH-deficient men (mean age, 37.6 +/- 3.9 yr) underwent GnRH dose-response studies at baseline and after treatment with dexamethasone (0.5 mg twice daily). Aromatase blockade caused significant lowering of E(2) (33 +/- 3 to 14 +/- 1 pg/mL; P: < 0.0005) with a corresponding increase in T levels (563 +/- 42 to 817 +/- 81 ng/dL; P: < 0.05). Treatment with ketoconazole resulted in equivalent suppression of E(2) (41 +/- 4 to 14 +/- 1 pg/mL; P: < 0.0005), but also induced castrate levels of T (491 +/- 28 to 40 +/- 3 ng/dL; P: < 0.0005). Both treatment regimens were associated with a significant increase in gonadotropin levels. For LH, the percent increase in serum levels after castration was almost 3-fold greater than that seen after selective E(2) withdrawal (275 +/- 23% with ketoconazole vs. 95.6 +/- 21% with anastrozole; P: < 0.005). Despite the divergent changes in T levels with these two maneuvers (a marked decrease after ketoconazole and a significant increase with anastrozole), the percent rise in FSH levels was similar in the two protocols (91 +/- 6% vs. 71 +/- 7%, respectively; P: = NS). Inhibin B levels were unchanged after selective E(2) withdrawal (156 +/- 23 vs. 176 +/- 19 pg/mL), but decreased slightly with ketoconazole (156 +/- 15 to 131 +/- 11 pg/mL; P: < 0.05). In contrast to the effects of glucocorticoid administration on gonadotropin secretion in women, no significant changes were observed in the GnRH-deficient men treated with dexamethasone in terms of mean LH levels (19.8 +/- 3.2 vs. 23.3 +/- 5.4 IU/L), mean LH pulse amplitude after GnRH (16.0 +/- 2.5 vs. 19.0 +/- 5.1 IU/L), or mean FSH levels (8.0 +/- 1.9 vs. 9.2 +/- 2.4 IU/L, pre vs. post). These studies provide evidence of differential regulation of gonadotropin secretion by T in the human male. T exerts both direct and indirect feedback on LH secretion, whereas its effects on FSH appear to be mediated largely by aromatization to E(2). From these data we conclude that in terms of sex steroid feedback, E(2) is the predominant regulator of FSH secretion in the human male.

Adult↗

PubMed2004

The effect of tactile feedback on pantomime of tool use in apraxia.

OBJECTIVE: To investigate whether apraxic patients' better performance with real tools compared to miming is due to the tactile feedback provided by holding the tool. METHODS: Ten patients with aphasia and apraxia from left hemisphere damage were asked to demonstrate the use of 12 tools and objects under three conditions: miming with empty hands, miming with an implement shaped like the handle of the tool, and using the real tool with its corresponding object. RESULTS: Whereas real tool use was much better than pantomime in all patients, tactile feedback from the isolated handle facilitated miming only in some and deteriorated it in others so that across the group there was no significant improvement. CONCLUSIONS: The better performance of real than of pretended tool use does not depend on tactile feedback per se, but on the mechanical affordances and constraints of tools and objects transmitted by this feedback in real use. Tactile feedback deprived of these contents and restricted to the shape of the handle does not substantially help produce the appropriate action.

Adult↗

PubMed1995

Feedback for participants in a health survey: feasible and useful.

The use of quantitative methods has often limited the communication between researchers and research participants to being one-sided. Use of feedback in survey-oriented research is one possibility for creating a more communicative relationship. After doing a postal survey of 2000 Finnish 45 to 64-year-old women about their climacterium we produced a feedback leaflet about the main results of the study and about climacterium in general and sent it to all respondents (n = 1713). Later a postal questionnaire concerning the feedback leaflet was sent to a consecutive sample of every eighth (n = 200) woman, of whom 153 (76%) responded. Most of the women gave neutral or positive responses to the content of the leaflet. There was more interest in the feedback among the younger and pre-menopausal groups than among the older or postmenopausal women. Some women wanted more information about climacterium-related issues than was possible to give in the space of eight pages. According to this experiment, feedback offers fresh view-points and valuable critique for researchers as a result of being more in contact with respondents.

Communication↗

PubMed2002

Glass-fiber self-mixing intra-arterial laser Doppler velocimetry: signal stability and feedback analysis.

We have developed a blood velocimeter based on the principle of self-mixing in a semiconductor laser diode through an optical fiber. The intensity of the light is modulated by feedback from moving scattering particles that contain the Doppler-shift frequency. Upon feedback the characteristics of the laser diode change. The threshold current decreases, and an instable region may become present above the new threshold. The amplitude of the Doppler signal turns out to be related to the difference in intensity between situations with and without feedback. This amplitude is highest just above feedback. The suppression of reflection from the glass-fiber facets is of paramount importance in the obtaining of a higher signal-to-noise ratio. Using an optical stabilization of the feedback, we optimized the performance of the laser-fiber system and the Doppler modulation depth and clarified its behavior with a suitable physical model. We also investigated the effect of the finite coherence length of the laser. We tested the efficiency of the self-mixing velocimeter in vivo with the optical glass fiber inserted in the artery with endoscopic catheters, both in upstream and in downstream blood flow conditions. For the latter we used a special side-reflecting device solution for the fiber facet to allow downstream measurements.

Animals↗

PubMed2005

Beam shaping by use of hybrid acousto-optics with feedback.

We theoretically demonstrate beam shaping through adaptive feedback in an acousto-optic device with electrical feedback by using experimentally determined parameters. Cases of positive feedback and negative feedback from undiffracted and diffracted orders are investigated. In addition, we demonstrate the dependence of the final value of the induced grating strength in the acousto-optic cell on the feedback parameters.

Algorithms↗

PubMed1986

The effect of alcohol on self-evaluation and perception of negative interpersonal feedback.

Recent theories of alcohol use and misuse assume that alcohol alters cognitive-perceptual mediating processes that indirectly reduce emotional distress. One view is that alcohol enhances perceptions of control and power. Alternatively, it has been suggested that alcohol is used to reduce self-awareness, perceptions of negative feedback and negative self-evaluations. The purpose of this study was to test these two hypotheses. Forty men, all college students, participated in the study and were randomly assigned to the four conditions in a 2 X 2 balanced placebo design. Subjects interacted with a woman confederate at two points in the procedure: first under positive feedback conditions and then, after beverage consumption, under negative feedback conditions. Both sequences were videotaped and eventually viewed by the subjects. Before and after each interaction period and after the videotape procedure, subjects completed rating forms which assessed their self-perceptions. Whereas perceptions of control and power were diminished when subjects were sober, the ratings of intoxicated subjects remained stable after they received negative interpersonal feedback. Alcohol impaired the perception of negative feedback and reduced negative evaluations of the videotaped sequences.

Adult↗

PubMed1990

Ageing does not influence the ultrashort feedback control of GnRH secretion in vitro.

Evidence indicates that long and short feedback systems are altered in the aged male rat. Data also indicate the existence of an ultrashort feedback mechanism controlling GnRH secretion. The present experiments were performed to test whether the ultrashort feedback control of GnRH is operating also in old male rats. Mediobasal hypothalami of 18-month-old male rats were perifused in vitro either in the presence or in the absence of a GnRH agonistic analogue (Buserelin: [D-Ser(TBU)6,Des-Gly10]GnRH ethylamide) and stimulated with 5-min pulses of K+ (for a total of six pulses) in order to test their ability to release GnRH. The hypothalamic fragment was exposed to the GnRH analogue either for a part of the experimental period (at the beginning or at the end) or for the whole duration of the perifusion. In both cases, the presence of the analogue diminished or totally abolished the responses to K+ stimulation. This is in line with the results obtained in young animals. The data suggest that the ultrashort feedback mechanism controlling GnRH release is normally functioning also in aged male rats despite the fact that other types of feedback mechanisms (long and short loop) are substantially altered.

Aging↗

PubMed1989

FSH concentrations and sensitivity to feedback in infant lambs from breeds differing in prolificacy.

Plasma FSH concentration was significantly higher in Romanov than Ile-de-France ewe lambs at 5, 6 and 7 weeks of age (P less than 0.001, P less than 0.02 and P less than 0.02, respectively) and at 5, 6 and 7 weeks of age (P less than 0.001, P less than 0.01 and P less than 0.05, respectively) compared to Finn lambs. FSH concentrations were similar and unaffected by time in Ile-de-France and Finn lambs. Ovariectomy at 5 weeks of age produced similar increases in FSH concentrations in Romanov and Ile-de-France ewe lambs, but at 3 months of age the increase in FSH concentrations after ovariectomy was significantly steeper (P less than 0.02) in Romanov than Ile-de-France lambs. Sensitivity to oestradiol feedback was related to the age of the lambs. At 5 weeks of age, oestradiol (30 micrograms in oil per lamb) produced a significant decrease (P less than 0.001) in FSH concentrations in Romanov and Ile-de-France lambs, demonstrating that negative feedback can be triggered by oestradiol at this age. Positive feedback after an oestradiol challenge was identified in lambs of both breeds at 6 weeks of age. Sensitivity to the negative feedback of follicular fluid compounds was also established at 5-6 weeks and did not differ between breeds. At 9-10 weeks of age, while there was no breed effect of an oestradiol challenge on FSH concentrations, suppression of FSH concentrations by follicular fluid was shorter in Finn than in the other lambs. As all the feedback mechanisms are functional at 5-6 weeks of age, it is likely that the between breed differences of FSH profile during infancy are linked to differences in gonadal development.

Animals↗

PubMed1985

Differential effects of gonadectomy on sensitivity to testosterone of brain centres associated with gonadotrophin negative feedback and with mating behaviour in rams.

Castrated sheep were used to study the effects of gonadectomy on sensitivity to testosterone of brain centres associated with gonadotrophin negative feedback and with mating behaviour. In the first experiment serum LH and FSH concentrations were determined in intact rams, recently castrated (2 days and 3 weeks) and long-term castrated animals (greater than 2 years, wethers) during intravenous testosterone infusion at physiological and supraphysiological levels. In intact rams, testosterone infusions effectively suppressed serum LH whilst FSH levels were suppressed only after prolonged infusion at the supraphysiological dose. Recently castrated sheep, which had higher gonadotrophin levels than intact rams, were less sensitive to testosterone feedback. Neither rate of testosterone infusion had any effect on the raised gonadotrophin levels in wethers. In a second experiment gonadotrophin concentrations and mating behaviour were determined in wethers bearing subdermal polydimethylsiloxane implants of testosterone, dihydrotestosterone and oestradiol. Testosterone implants stimulated mating behaviour in all wethers but suppressed gonadotrophins in only a proportion (three out of seven) of the animals. Both oestradiol and dihydrotestosterone suppressed LH and FSH in all wethers, whilst oestradiol, but not dihydrotestosterone, also stimulated mating behaviour. The present findings indicate that testosterone imposes continuing negative feedback on gonadotrophin secretion and that changes in the gonadotrophin regulatory system, which lead eventually to a loss in sensitivity to testosterone feedback, develop soon after gonadectomy. The results also provide the first direct evidence that longterm gonadectomy in male sheep has differential effects on sensitivity to testosterone of brain centres associated with gonadotrophin negative feedback and with mating behaviour.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1986

The effects of performance feedback on the safety of client lifting and transfer.

Individual written and verbal performance feedback was examined to determine its influence on the safety with which physically disabled clients were transferred. Two client-transfer techniques were task analyzed and six direct service providers' on-the-job performance was measured weekly. A multiple baseline across settings and subjects was used to evaluate effects of the feedback. Consumer satisfaction and the costs of the procedures were also assessed. Results showed that feedback was consistently followed by improvements in safe performance. These improvements tended to maintain as feedback was faded. Participants favorably rated the feedback procedure and consistently recommended its use with other staff.

Accident Prevention↗

PubMed1981

Interaction of sensory feedback: a child-adult comparison of oral sensory and temporal articulatory function.

Recent studies have demonstrated a systematic increase in lingual sensory thresholds and a temporal articulatory reorganization in subjects speaking under exposure to auditory masking. These data suggest that auditory and lingual sensory feedback systems exist in a balanced interaction specific to the oral articulations involved in speech production. The present study attempted to gain additional information on this proposed interaction. Lingual sensory and temporal articulatory measurements were obtained from 10 adults and 10 children under each of four feedback conditions: (1) normal feedback, (2) exposure to binaural auditory masking during speech, (3) topical application of anesthesia to the lingual dorsum prior to speech, and (4) combined masking and anesthesia. Analysis indicated that children had lower lingual sensory thresholds than adults in all conditions and that they were more susceptible to the disruption of auditory feedback. Also, measurements of durations of vowels indicated no age-related differences with durations in both groups increasing when auditory feedback was impaired.

Adult↗