Learning a Spatial Skill for Surgery : How the Contributions of Abilities Change With Practice

reasoning 27.0 (7.5) 26.8 (7.4) Mental rotation 34.9 (18.5) 38.9 (19.4) Visualization of views 11.5 (7.8) 12.8 (8.3) Values in parentheses indicate standard deviations. 492 M. Keehner et al. Copyright # 2006 John Wiley & Sons, Ltd. Appl. Cognit. Psychol. 20: 487–503 (2006) participants with the task) comprised five target boxes that were relatively easy to solve because they required laparoscope rotations that deviated no more than 59 from the starting position. Four sets of learning trials were more difficult; each set comprised five target boxes requiring rotations between 60 and 180 . A final transfer set of trials comprised five novel target boxes with the same difficulty parameters as the boxes in the learning trials. In all sets of trials, the five target boxes were distributed across space in a quasi-random configuration. Procedure The experiment was divided into one pre-learning session (in which the psychometric tests were administered) and 12 learning sessions (in which the laparoscope task was administered), scheduled over three weeks. In the first laparoscope learning session, participants were informed about the general purpose and procedure of the study. The experimenter described the angled lens without giving information that would suggest a specific strategy for its use, as this is the norm in real surgical training. Participants familiarized themselves with the laparoscopic workstation by completing the five simple practice trials. Thereafter, participants completed 12 learning sessions, each comprising 4 sets of 5 boxes each. In each session, the four sets of learning trials were presented in a random order, determined by a Latin square. The first learning session lasted up to 60 minutes, and subsequent learning sessions lasted between 30 minutes and 5 minutes (on average, time spent in the learning sessions decreased as learning progressed). Participants had no more than one learning session per day. Sessions were scheduled on consecutive days where possible, with a maximum of one day’s break allowed per week (with the exception of the two intervening weekends, when no learning sessions occurred). In the final session, participants completed the transfer trials immediately following the last set of learning trials. Each set began with the participant zooming out (by drawing the laparoscope back) to increase the field of view so that all five boxes were visible. When the participant was ready, the experimenter initiated the trial via a key press, and one target box turned from red to green. The participant’s task was to manoeuvre the laparoscope to look directly into Figure 2. Virtual reality set-up in the simulated laparoscope task. See text for details Abilities in learning a spatial skill 493 Copyright # 2006 John Wiley & Sons, Ltd. Appl. Cognit. Psychol. 20: 487–503 (2006) the target box, so that the inside of the box could be seen straight on. When the laparoscope had been positioned correctly, the colour of the box changed back to red, indicating successful completion of that target. A box in a different location then turned green, indicating that it was the next target. It was generally necessary to zoom out between targets to bring the next target into view. Participants proceeded until they had looked directly into all five boxes. The order of boxes was randomized in each set of trials. Participants were instructed to complete the task as quickly as possible. Response time was recorded automatically. The maximum time allowed per box was 3 minutes. If a box was not solved within this period, a time of 180 seconds was assigned to that trial.