{'fraction_non_alphanumeric': 0.014857881136950904, 'fraction_numerical': 0.009689922480620155, 'mean_word_length': 5.122529644268774, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
A Study on Perceptual Processing of Teeth Images with Occluded Areas Based on the Analysis of Event-related Potential

Based on visually obtained information such as a spatial arrangement of teeth and tooth shape, dentists can distinguish the tooth type by extracting and collating dental features. They can perform tooth identification regardless of whether the presented tooth images are complete or incomplete. The aim of this study was to clarify the cognitive information processing of tooth images with occluded area. The subjects were 11 fifth-year dental students with both dental knowledge and experience of clinical training（average age 23.8 years）. The complete tooth images or incomplete tooth images（with occluded areas）were presented according to certain conditions, and an electroencephalogram analysis was performed focusing on event related potential. The P300 is an evoked potential that occurs 300 ms after an event and is composed of P3a and P3b. They are thought to be the stage for information processing after re-ceiving visual information. In our study, the results of P3a showed that the occipital and temporal regions adjacent to the ventral pathway were more active in incomplete image processing than complete image processing but that the activity decreased in the parietal region. In P3b, the activity of the parietal region close to the dorsal pathway was higher, but the activity of the temporal region was lower. It was concluded that the visual complement was done for the recognition of the occluded tooth images.