Abstract:

Attentional templates can facilitate the target search process by enhancing relevant information and suppressing irrelevant information during the search task. According to the results of recent studies on the internal mechanism of attentional templates, the main findings are summarized in terms of the information relied on in the establishment of attentional templates (establishment process), the relationship between attentional templates and memory (stored process), and the mechanism of attentional templates promoting search (function mechanism).

Firstly, the semantic information and visual feature information cannot be well separated in the current experimental studies, so it is not clear whether it was based on semantic or visual feature information in the process of establishing the attentional templates. Secondly, in some earlier studies, researchers equate attentional templates with working memory, believing that attentional templates are stored in working memory. However, recent studies have found that attentional templates can be stored in both the working and long-term memory. But the number of templates stored in working memory is still controversial. Some researchers believe that simultaneously searching for two items is worse than searching for one item, as shown by evidence for storing only one template in the working memory. Similar results may be found when two templates are stored in the working memory, such as the following possibilities: when two templates were stored in the working memory simultaneously, each template receive fewer resources compared to storing only one template due to the limited resources of the working memory; when two templates were activated at the same time, the information in the online state will interfere with each other, resulting in poorer performance of searching for two items simultaneously than searching for one item; when two templates are switched to each other, the switch takes time, and the simultaneous memory representation will be damaged, which will also reduce the efficiency of searching for two items at the same time than that of searching for one item. Finally, there are differences in the mechanism of different types of attentional templates. The target template and the template for rejection may promote the search through different mechanisms. The right posterior temporal cortex, anterior superior parietal lobule, bilaterally at the occipital pole and lateral occipital cortex play an important role in promoting the search of the target through the target template. The activation of posterior parietal cortex and the area of posterior parietal cortex bordering precuneus are associated with the templates for rejection in filtering task-irrelevant information.

Furthermore, we know very little about how template information is transmitted and used during visual search. The mechanisms by which templates facilitate search may also vary across populations, and that some findings in normal individuals may not be universally applicable. As well as the controversial in active attentional suppression hypothesis and search and destroy hypotheses for explaining the mechanism of template for rejection in the suppression of distractors. Therefore, future research should pay attention to how the internal information is transmitted during the establishment of attentional templates, the neural mechanisms of attentional templates in different populations, and resolve theoretical disputes about the suppression mechanism of rejection templates.

Key words: attentional templates, rejection template, neural mechanism, memory