<p>In this study, the effects on concentration of attention, cognitive activity such as memory was examined in consideration of humans' cognitive characteristic over 3D images about the partial 3D image which changed a part of picture. The experiment of concentration of attention was carried out by measuring reaction time in visual search task using a simple visual target and eye fixation while viewing natural color image. On the other hand, the experiment of cognitive effect such as memory, the searching time until the changes are recognized were computed using the change blindness subject. That needs the cognitive activity of comparing by memorizing a picture temporarily while turning a look for detection of change. As a result, it was suggested by the partial 3D image that an object has the cognitive effect which is easy to go up to consciousness and to remain in memory.</p>