engleski

Visual working memory capacity for emotional facial expressions

The capacity of visual working memory is limited to no more then four items, and at the same time, it is limited not only by the number of objects, but also by the total amount of information that needs to be memorized. For example, Alvarez & Cavanagh (2004) discovered inverse relation between the information load per object and the number of objects that can be stored into visual working memory. They found that visual working memory capacity is the lowest for shaded cubes or Chinese letters, and highest for colored squares. The objective of the present experiment was to assess and quantify visual working memory capacity for emotional facial expressions. In order to estimate the capacity, change detection paradigm was applied. Twenty-four participants were presented with pictures of human emotional facial expressions, in 1008 experimental trials per participant. Each trial began with a presentation of a fixation mark, which was followed by a short simultaneous presentation of six emotional facial expressions. After that, a blank screen was presented, and after such interstimulus interval, one facial expression was presented at one of previously occupied locations. Participants had to answer if the facial expression presented at test is different or identical as the expression presented at that same location before the retention interval. Capacity was estimated by the formula constructed by Pashler (1988), which is adopted from signal detection theory, and the formula provided by Švegar (2008), which computes the memory capacity directly via the percentage of correct answers. The conclusion of the experiment is that we can not simultaneously hold more then two or three emotional facial expressions in our working memory. According to Pashler, visual working memory capacity for facial expressions equals round 3.07, while according to Švegar, it is limited to approximately 2.14 expressions.

visual working memory capacity; emotional facial expressions; change detection paradigm

nije evidentirano