Abstract: The study of attentional capture has focused primarily on measuring the effect of an irrelevant stimulus on task performance, termed implicit attentional capture. In essence, these studies explore how well observers are able to ignore something that they expect but know to be irrelevant. By contrast, several new paradigms that explore the same issue have found unexpected objects often fail to capture attention, termed “inattentional blindness.” Many researchers are extremely interested in this field and have consequently conducted many researches related to this subject. They have explored (1) the effect of stimulus familiarity, size, location, and distance; (2) the similarity between attended and unattended stimuli; (3) the zone of attention; (4) perceptual load; and (5) expectation and expertise on inattentional blindness. The current study aims to examine the effect of stimulus type and consistency of semantic representation on inattentional blindness.
The study employed a two-factor mixed design. The participants comprised 40 subjects who attended the baseline tests involving pictures and words and 52 subjects who attended the inattentional blindness experiment. The attended stimulus type was the between-subject factor, while the consistency of semantic representation was the within-subject factor. The attended picture group and attended word group each included 23 valid subjects. Using superimposed picture and word streams, we explored the effect of stimulus type and consistency of semantic representation on inattentional blindness. An ANOVA was performed to analyze the results. We explored the baseline recognition score of pictures and words; moreover, we compared the inattentional blindness scores with baseline scores.
The results showed that in comparison to baseline scores, inattentional blindness was significant when the superimposed pictures and words were presented. Regardless of whether the attended stimuli were pictures or words or whether the representation between the pictures and words was consistent, Subjects were able to detect words more easily when the words and pictures had the same semantic representation. In addition, unattended stimuli captured the attention of subjects more easily when they had the same semantic representation as the attended stimuli.
Inattentional blindness provides a new visual angle for the research of attentional capture. Traditional implicit paradigms explore how well observers are able to ignore something that they expect but know to be irrelevant, whereas in explicit attentional capture, the critical question is how likely are subjects to notice something that is potentially relevant but unexpected. In this research, we found that meaning was an important factor in attentional capture. Moreover, the results provided some useful suggestions for advertisements. If advertisement producers would like the audience to be influenced by their advertisements, then they should display pictures that the audience is interested in and subsequently, in the background, present their products using words. Furthermore, for better attention capture, the representation of objects using both pictures and words is recommended

Key words: inattentional blindness, stimulus type, consistency of semantic representation, attended stimulus, unattended stimulus