## 4 Discussion  
### Effects of Combined Icon Types on Visual Cognitive Performance of Construal Level Traits Users  
Among the four combined icons of Ci + Ct, Ci + At, Ai + Ct and Ai + At, all users achieved the best response time, match rate, and cognitive fluency with Ci + Ct, followed \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & \multicolumn{3}{c}{**Direct Effect of Combination Design Type**} \\ \hline  & **Coeff** & **Boot-S.E** & **BootLLCI** & **BootULCI** \\ \hline Constant & 0.908 & 0.029 & 0.851 & 0.966 \\ Ci + At & \(-\)0.682 & \(-\)0.682 & \(-\)0.732 & \(-\)0.632 \\ Ai + Ct & \(-\)1.053 & \(-\)1.056 & \(-\)1.172 & \(-\)0.944 \\ Ai + At & \(-\)1.898 & \(-\)1.899 & \(-\)2.055 & \(-\)1.761 \\ \hline \hline \multicolumn{4}{c}{**Indirect Effect of Combination Design Type \(\times\) Construal Level**} \\ \hline  & **Coeff** & **Boot-S.E** & **BootLLCI** & **BootULCI** \\ \hline Ci + At & 0.065 & 0.054 & \(-\)0.037 & 0.173 \\ Ai + Ct & 0.316 & 0.072 & 0.178 & 0.461 \\ Ai + At & 0.394 & 0.094 & 0.218 & 0.585 \\ \hline \hline \multicolumn{4}{c}{**Index of Moderated Mediation**} \\ \hline  & **Index** & **Boot-S.E** & **BootLLCI** & **BootULCI** \\ \hline  & 0.351 & 0.282 & 0.293 & 0.405 \\ \hline \hline \end{tabular}
\end{table} 
Table 6: The mediating effect of cognitive fluency in combination design style and construal level on match rate. Figure 7: The mediating model of cognitive fluency in match rate. Note: \({}^{*}\)\(p\)\(\leq\) 0.05.  
by Ci + At, Ai + Ct and Ai + At. Our findings are consistent with previous research. When the icons are presented in the form of Ci + Ct, because of the high reduction degree of concrete graphics to physical things and the straightness of the text, the graphics' visual attributes and the text's semantic attributes will be quickly encoded directly into the human brain [53]. However, the graphics and text in the combined icon are the same in the source and target domains, or at least belong to the same category. Therefore, the graphics-text semantic network is very close. Therefore, when concrete graphics match concrete text, it is easier to understand, and can lead to the best visual cognitive performance, which can be explained by the dual-coding theory [54]. In the two types of icons of Ci + At and Ai + Ct, the graphic is related to the texts' source and target domain, but it is not in the same category. Hence, the user needs to convert the abstract concept of the textual semantics in the brain to match the concrete graphic, or convert the extended abstract graphic to the corresponding real object, and match this with the concrete text [41; 55; 56]. Among these two types of icons, either the source domain or the target domain needs to be converted, and this means that more cognitive resources are required relative to the type of Ci + Ct. However, the processing of graphic attributes in the human brain is more effective than that of text, so in the two types of icons, the cognitive performance of Ci + At is better than that of Ai + Ct [57]. In Ai + At, both the graphic and text attributes need to be retrieved and converted in the brain before matching, so it is easy to understand why the visual cognition of this type of icon is lower than that of the first three types, and more complex [47]. The Interactive Effect of Combined Icon Types and Construal Level Traits on Users' Visual Cognitive Performance  
In the visual cognition of the combined icon, the subjects judged whether the abstract or concrete graphic and the corresponding text clues were consistent. When both graphic clues and text clues are concrete, the response time, match rate, and cognitive fluency of the two types of users do not significantly differ. The cognitive load is minimal, and almost indistinguishable. Construal level is a stable personality trait. Users with high construal levels are better at initiating abstract coding to represent brain information. On the contrary, users with low construal levels are more inclined to concrete coding.