Scene and not seen: Noticing changes in complex environments

Purpose. To investigate- our ability to analyse dynamic, natural scenes with regard to the attributes of their constituent object 5. Methods. A street was videoed 12 tinier from a car travelling at 30km/h. The video; differed only by chaages made in the location, colour, orientation or presence of 3 fron 6 objects. Thirty new videos were generated by mixing two of the 12 videos. Mixing imolved recording 8 frames from video A, 8 frames of a uniform grey image, 8 frames from video B, a further 8 py images, and then back to video A, until 400 frames had been processed. fYalMIee dsfl from each video sequence so as to avoid abrupt chang|| .a poeHipg,M>4bEiJNflaf testing, subjects saw the new videos and had V jjjha .etante ifopM the Kne. Results. Six naive subjects Meeting changes. Subjects' ability taaq$ppiilf feotii by the object changed and the type of wige ObAM Witt O tfete nevfe-r noticed whereas changes in a fr fft lifef BS flfff 5d at a similar diataece from the roadaide, were'Minwra noticed (98%) If noticed, changes were always ascribed To the correct object, but wg often misclassif ed as to the type of change (up to 30% for one of therobjects). The tirfleylelay between t le detection of each change was remarkably tjonsiatcat (as 3.5), The removal of object; was significantly more noticeable than claes ifisobjaettour, locajpn or orientation Comparable results have also been obtained in a virtual mode Frhis environment permitting better stimulus control and subject interaction. GjrtJEisions By using th; video mixing technique described above, it has been friri analyse the speed and accuracy of the analysis of a dynamic real-world scenssfsfe results demonstrate that il e instantaneous, full and detailed perception of a,8pi which we experience, is simply illusory, confirming other work on static scenes. Fwork also demonstrates that including multiple changes may cause changes to be ffoticed but falsely categorised, and th it the delay between each report of a change ia remarkably consistent, suggesting a tine-windowed shifting of attention.