Distraction by unexpected sounds: comparing response repetition and response switching.

Numerous studies using oddball tasks have shown that unexpected sounds presented in a predictable or repeated sequence (deviant vs. standard sounds) capture attention and negatively impact ongoing behavioral performance. Here, we examine an aspect of this effect that has gone relatively unnoticed: the impact of deviant sounds is stronger for response repetitions than for response switches. Our approach was two-fold. First, we carried out a simulation to estimate the likelihood that stimuli sequences used in past work may not have used balanced proportions of response repetition and switch trials. More specifically, we sought to determine whether the larger distraction effect for response repetitions may have reflected a rarer, and thereby more surprising, occurrence of such trials. To do so, we simulated 10,000 stimuli sets for a 2-AFC task with a proportion of deviant trial of 0.1 or 0.16. Second, we carried out a 2-AFC oddball task in which participants judged the duration of a tone (short vs. long). We carefully controlled the sequence of stimuli to ensure to balance the proportions of response repetitions and response switches across the standard and deviant conditions. The results of the stimuli simulation showed that, contrary to our concerns, response switches were more likely than response repetitions when left uncontrolled for. This suggests that the larger distraction found for response repetition in past work may in fact have been underestimated. In the tone duration judgment task, the results showed a large impact of the response type on distraction as measured by response times: Deviants sounds significantly delayed response repetitions but notably accelerated switches. These findings suggest that deviant sound hinder response repetition and encourage or bias the cognitive system towards a change of responses. We discuss these findings in relation to the adaptive nature of the involuntary detection of unexpected stimuli and in relation to the notion of partial repetition costs. We argue that results are in line with the binding account as well as with the signaling theory.

Effectiveness of the Godelieve Denys-Struyf (GDS) method in people with low back pain: cluster randomized controlled trial.

BACKGROUND: The Godelieve Denys-Struyf method (GDS) is a motor learning intervention that may be applied in group or individualized sessions. OBJECTIVE: The study objective was to compare the effectiveness of routine physical therapy, group GDS (GDS-G) sessions, and group and individualized GDS (GDS-I) sessions. DESIGN: This was a cluster randomized controlled trial. SETTING: The study took place in 21 primary care physical therapy units ("clusters") of the Spanish National Health Service (SNHS). PARTICIPANTS: The participants were 461 people with subacute and chronic low back pain (LBP). INTERVENTION: Clusters were randomized into 3 groups. All participants received medical treatment and a 15-minute group education session on active management. Additional interventions were as follows: control (fifteen 40-minute sessions of transcutaneous electrical nerve stimulation, microwave treatment, and standardized exercises), GDS-G (eleven 50-minute group GDS sessions), and GDS-I (the same 11 sessions plus four 50-minute individualized GDS sessions). MEASUREMENTS: Primary outcomes at baseline and 2, 6, and 12 months later were LBP and pain referred down the leg (separate pain intensity numeric rating scales) and disability (Roland-Morris Questionnaire [RMQ]). Secondary outcomes were use of medication and self-reported health (mental and physical component summaries of the 12-Item Short-Form Health Survey [SF-12]). Separate linear mixed models for LBP, pain referred down the leg, and disability were developed to adjust for potential confounders. Randomization, outcome assessment, and data analyses were masked. RESULTS: At 12 months, disability improved 0.7 (95% confidence interval [CI]=-0.4, 1.8) RMQ point in the control group, 1.5 (95% CI=0.4, 2.7) RMQ points in the GDS-I group, and 2.2 (95% CI=1.2, 3.2) RMQ points in the GDS-G group. There were no differences in pain. LIMITATIONS: The amount of exercise was smaller in the control group, and GDS-I sessions were provided by junior physical therapists. CONCLUSIONS: The improvement in disability was slightly higher with group GDS sessions than with the program routinely used in clusters within the SNHS. Adding individualized GDS sessions eliminated this advantage. Further studies should compare the GDS with other types of exercise.

Conocimiento de los médicos y la población cubana sobre los ensayos clínicos / Knowledge of the Cuban doctors and population about the clinical assays

Se elaboraron y validaron 2 encuestas con el objetivo de determinar la percepción y el conocimiento de los médicos y el público sobre los ensayos clínicos. Los médicos fueron encuestados en instituciones hospitalarias hasta un total de 267 especialistas. Se encuestó una muestra de 405 personas tomadas al azar de la población en general. Algunos médicos y el público en general tienen dificultades para explicar que es un ensayo clínico. En Cuba se han incrementado los conocimientos sobre los ensayos clínicos, sin embargo, aún no existe una cultura general sobre este tipo de investigación. Deben aprovecharse todas las posibilidades de los medios de comunicación para la divulgación de temas relacionados con los ensayos clínicos