Erlotinib Educates Itself, Scheduling A Arctic Cruise
To perform the orientation constancy task, the subject ... Length constancy task To evaluate length constancy, participants were presented with 5 lengths of bars (5AFC: 3 cm by either 9, 12, 15, 18, or 21 cm), while the bar was placed in one of four orientations (0, 90, 45, or ?45�� relative to vertical; clockwise rotations correspond to positive angles) (Figure ?(Figure1B).1B). Participants were asked to determine the length of the bar presented independent of the angle that it was presented at. The subject was seated about 81 cm from the bar to be evaluated. Participants first performed the task with the vOICe device (original task) and then with vision (touch for the blind; control task) in each session. The bar lengths and angles were randomized in order for each session, which included 20 trials for each task performance (original and then control). Head tilt instructions varied across subjects (further information is provided in the length constancy training details section). Before starting the training, participants were briefly shown the line lengths in a subset of the angles. Participants were given feedback for each trial, and if necessary shown an example line length following a trial as a reminder. The vOICe device Participants used a vOICe device to learn the constancy tasks. The vOICe device uses a camera embedded in a pair of sunglasses or a webcam attached externally to glasses. Sighted participants were requested to close their eyes during training and evaluation, and wore opaque glasses and/or a mask to block direct visual input. The camera provided a live video feed of the environment, and a small portable computer was used to MCF2L encode the video into sound in real time. The vOICe software was obtained online at seeingwithsound.com and was used for the video-to-sound encoding. Two blind participants were forced to transition from one camera and device setup to another setup part way through training due to device failure; their data did not indicate any difficulty with this transition. In principle, any technical differences in the vOICe device setup would not make any difference in terms of training efficiency and task performance, except for possible minor differences in spatial perception due to the gain of the camera, camera field of view, and camera placement. In particular, field of view changes between cameras may alter the absolute size of the line however we did not want participants to memorize the sound durations (or another auditory feature) for each of the bars, and re-iterate that memorized element. Rather, we wanted participant to learn how to interpret vOICe and learn how to identify different line lengths at different angles (as is done in vision). The training sessions were video recorded for later data analysis. The participants were informed of the recording and consented to it.