Before, during and after you disappear: aspects of timing and dynamic updating of the real-time action simulation of human motions

The detailed dynamics of action simulation was investigated using the occluder paradigm: a point light actor (PLA) was shown, then briefly occluded from view, during which period action simulation was generated. Following occlusion, the PLA reappeared, either a progression of the motion as it should be post-occlusion or temporally shifted earlier/later. Participants made judgements on whether the reappearing PLA was too early or too late to be a correct continuation (Experiments 1 and 3) or whether it was a veridical continuation or not (Experiment 2). Over three experiments we asked how action simulation is affected by motion information before, during and after occlusion. Reducing motion presented before occlusion retained the accuracy of action simulation judgements. Presenting 4 frames (67 ms) of PLA motion during the occluder duration dynamically updates or altogether regenerates the action simulation. Reducing the duration of the test motion after the occluder decreases judgement precision, which we interpret as a limitation in the process of postdictive motion judgments. Overall, this is further evidence that the action simulation process is remarkably adapted to making human motion predictions.     

The surgical anxiety questionnaire (SAQ): development and validation

Objective: Preoperative anxiety is often assessed using general anxiety measures; existing specific measures might lack content coverage and/or are not psychometrically validated. This study aimed to develop a new self-report measure of surgery-specific anxiety and test its psychometric properties.

Design: The surgical anxiety questionnaire (SAQ) was developed from themes identified in qualitative research and reviewed by an interdisciplinary expert team. It was administered preoperatively to 135 patients (56% female, mean age 51) on the day of surgery alongside additional measures of preoperative anxiety, state anxiety, perceived stress, depression and social desirability. Follow-up assessment was conducted immediately post-surgery and two weeks post-surgery (n?=?114) to examine recovery and predictive validity of the scale.

Results: Factor analysis revealed a three component structure, including: concerns about health (six items), concerns about recovery (four items) and concerns about procedures (four items). Three additional items of relatively high concern were retained in the total score (17 items). The SAQ displayed good reliability, validity (content, construct and predictive) and adequate overall psychometric properties.

Conclusions: Preliminary results suggest that the SAQ is a promising tool for measuring preoperative anxiety and predicting recovery. Recommendations for future research include employing a confirmatory factor analysis and examining test-retest reliability.