Abstract:

In real life, people occasionally perceive an object as something non-existent, called pareidolia. Among all forms of pareidolia, people are more likely to recognize a face from an object. Face pareidolia has been widely utilized in art, advertising, and design, but its occurrence mechanisms remain unclear. Previous studies have used various paradigms to explore the occurrence mechanisms of face pareidolia. According to the different paradigms used, the occurrence mechanisms of face pareidolia have been deeply discussed from top-down and bottom-up visual signal processing pathways. However, due to the variety of paradigms, face pareidolia occurrence mechanisms and potential applications are still in their infancy. There has been no systematic theoretical construction either. Based on the two visual processing pathways, we categorize two types of paradigms: the pareidolia monitoring paradigm (face pareidolia in a bottom-up pathway) and the pareidolia discrimination paradigm (face pareidolia in a top-down pathway). To provide future research insights, we summarize the two paradigms from three perspectives, including stimuli, experimental procedures, and measurements. In addition, according to the perceptual prediction model, there are similarities and differences in the occurrence mechanisms of the two paradigms. Both paradigms have analogy, association, and prediction processes. However, the pareidolia monitoring paradigm focuses on rapid prediction generation through a single analogy and association process. The pareidolia discrimination paradigm focuses on the subjective expectation codes feedback to the analogy association process and then affects the subsequent prediction. In addition, the applications of facial illusions in clinical diagnosis, product, and advertising packaging are also listed. First, children with autism are less likely to produce face pareidolia than normal children, but they are still able to have face pareidolia. Moreover, there are connections between visual illusions and visual hallucinations in clinical diagnosis. Pareidolia could be used as a measurement of subclinical hallucinations. In commercial applications, the prominence of pareidolia elements in paintings, architecture, and advertising can attract consumers’ attention and facilitate their emotional or trait attributions to objects and consumer behavior. Future studies are suggested to develop new paradigms to explore further the interaction between top-down and bottom-up mechanisms of face pareidolia.

Key words: face pareidolia, face processing, occurrence mechanisms