Study on the Effect of Spatial Cognition Methods on Indoor Emergency Evacuation

In building re emergencies,way-nding capabilities can affect people's evacuation eciency and chances of survival.The purpose of this paper is to explore the inuence of spatial cognitive methods on people's way-nding ability.In this research, we used VR technology to conduct experiments. In an immersive virtual environment,64 participants were asked to actively explore virtual malls by using YAH navigation and paper maps to nd destinations and complete buying tasks,respectively.After that,32 participants needed to alienate the virtual mall with a time limit,while the else had to complete the same task without a time limit. In the experiment,the participants were exposed to the environment for the rst time and were unfamiliar with it.The results showed that participants using paper maps walked longer(710 m vs 932 m) and took more time(666 s vs 922 s) to complete tasks of evacuating the mall than those who used YAH navigation maps.The ndings also showed that participants spent more time(521 s vs 790 s)looking for exits under time constraints and found evacuation tasks more dicult.This article discusses the mechanisms of these ndings.


Introduction
Fire is a serious disaster in interior buildings.According to the data of the National Fire Authority, in the rst quarter of 2021,a total of 389.77 people died due to building res (https://www.119.gov.cn/article/3xBeByIHerh).In an indoor re,the e ciency of evacuation and the chances of survival are greatly affected by the way-nding 66 .Way-nding is a process of people looking for a destination along path 28 .In essence,it is an action of cognition and problem solving,which consists of cognitive processes such as reading a map,remembering the route, nding the position and maintaining the direction through external features or landmarks 9-18 .
Self-orientation and spatial orientation are two key processes in way-nding.However,with the development of the commercial economy,the tendency to be complicated of the internal structure of buildings not only increases the cognitive burden but also makes it di cult for people to nd their way 2 .People's spatial knowledge of an unfamiliar environment of buildings comes from their cognition of spatial information such as landmarks,routes,and the whole in the environment 49. Spatial knowledge is stored in people's mental representation of space,known as cognitive maps 23 .In the process of waynding,people extract spatial knowledge through cognitive maps 19 and formulate reasonable way-nding strategies to guide way-nding behaviors [50][51] .The ability to nd ways depends on people's use of route knowledge or overall knowledge 2 .
Maps are a major tool for people to obtain spatial information in an unfamiliar built environment 42 ,which is bene cial for people to form cognitive maps covering the overall spatial information 5 .In the process of map navigation,people can obtain spatial geographic information about the entire environment from the map and carry out self-positioning and spatial orientation by combining the mapping between the text interface and environmental graphics 65 .Although paper maps can provide participants with complete spatial geographic information,they also increase the cognitive burden of users,who need to quickly identify spatial information,plan the path and reach the destination within a limited time 48 .
With the development of modern technology,a large amount of spatial geographic information is transmitted electronically through mobile phones and the Internet 75 5 .People who can place themselves in the physical space and space are shown in the map symbol matching, real-time position their position in space 30 68 ,and obtain more spatial information in a short time 78,4 for spatial orientation and routes nding 11,32 .Compared with traditional paper maps,electronic maps have the advantage of quantitative judgment and can better communicate landmarks and route knowledge to users.However,some researchers have proposed that the use of electronic navigation is not good for people to acquire spatial knowledge about the environment 24 25 42 . Moreover,compared with more traditional way-nding methods such as paper maps, technology-assisted way-nding will hinder people's acquisition of spatial knowledge 18 41 42 44 46 .
Because of its real-time and interactive characteristics,electronic maps have been widely used in life However,as a carrier of information describing human life,paper maps still plan an important role in people's way-nding process,which is the priority for people to nd their way 22 . Therefore,it is necessary to compare paper maps and electronic maps in modern society. Previous studies on paper maps and electronic maps mainly focus on outdoor way-nding and exploratory research 5,6 .For example,research on the application of paper maps in modern digital mapping society 22 ;research on indoor navigation using augmented reality 4 etc.,while there are few studies on people using maps for indoor waynding.Second,in previous studies,paper maps and various electronic maps are mainly used in waynding behavior under normal circumstances, such as different studies of augmented reality (AR) and binary navigation electronic maps in people's way-nding behavior 15 .The in uence of different information formats and spatial cognition on individual way-nding performance 2 .There is a lack of research on the design of indoor navigation interfaces compatible with human information processing in emergency situations,such as emergency evacuation 61 .Finally, when people are under great psychological pressure, which type of map is more e cient for evacuation is also a question worth exploring.
To understand indoor way-nding behavior e ciently and accurately, researchers have used various methods,such as questionnaires 12 ,posture estimation 60 ,and real-time tracking methods 29 .However,these experimental methods have some limitations.First,they lack overall experience with the environment.Second,they are expensive.Three,it is di cult for people to collect data and set up a controlled experimental environment.In recent years,virtual reality(VR) has been widely used in the research of human navigation and way-nding behavior 6 30.70 and is a "real or simulated environment that the perceive experiences remotely" 53 .VR (virtual reality) can provide a highly realistic virtual environment (IVE) to evoke participants' psychological and behavioral responses to a simulated environment with high ecological validity 30 61 .The immersive virtual environment (IVE),as a new experimental method,provides a feasible alternative for indoor way-nding behavior research.Using an IVE-based approach,our goal is to examine two questions: First,how do different ways of spatial cognition in indoor environments affect people's ability to nd exist?
Second,how does stress in re evacuation interact with spatial cognitive patterns to affect people's ability to escape re emergencies?

Participants
In total,64 participants with normal vision or correction,no color blindness or other eye diseases were included in our research,and 32 participants were men;the other participants were women.They were randomly divided into 4 groups of 16 people,equally male and female.The experimental groups as shown in Table 2.The participants in the included articles had a mean age of 22-23 years and an equal percentage of men and women.Each participant received 50 CNY for their participation.The participants were informed that they could quit the experiment at any time and were asked to sign an informed consent form before the experiment began.The study was approved by the Ethics Committee of Sichuan Normal University and all experimental procedures were performed in accordance with the Declaration of Helsinki.

Experimental equipment
To compare the different in uences of modern navigation systems and traditional paper maps on emergency evacuation behavior in indoor res,we selected one of the common navigation methods in VR,the YAH navigation map,which can be marked in real time for participant spatial locations that can be experimented with,and a traditional paper map to experiment.

Experimental environment scenario
In April 2021,a major re in a commercial square in Anhui Province resulted in four deaths. In this experiment,we selected it as the script and took a medium-sized shopping mall as the experimental scene.Before the re in the mall,the milk tea shop is launching a new ice cream.To eat the ice cream,everyone crowded in front of the milk tea shop to wait.In the experiment,all participants needed to arrive from the same mall entrance to buy ice cream at the milk cream store selling ice cream.

Experimental scene
The IVE used in this study is the rst oor of a large virtual shopping mall,50 meters long, 40 meters wide,and 4 meters high.As seen in Fig. 1,there are 15 east-west stores in the mall,and a comprehensive mall is distributed in the center of the mall,including jewelry,clothing and other shops.Milk tea shop,route,and re point have been replaced by small red ag,color line,and ve-pointed star,respectively.
The mall has designed 4 conventional entrances and exits and ve evacuation routes,as shown in Fig.   2.Furthermore,the participants did not walk through the walls across the IVE.As shown in a pentagram symbol in Fig. 1,there is 1 re site for emergency re experiment conditions.Flames at the re point can spread to 3 m*4 m and smoke to a considerable area to ensure that they can be seen anywhere in the mall (Fig. 3).

Experimental design
In this experiment,participants were divided into four groups,two of which needed to experiment by using paper maps,while the other two groups were required under the guidance of the YAH navigation map.In the experiment, the participants needed to complete the buying and evacuation tasks.As shown in Table 2.
During the buying task,participants in the paper map and YAH navigation map groups needed to arrive at the milk tea shop at normal walking speed (1.2 m/s) to buy ice cream.Participants in the YAH navigation map group needed to set 5 coupons in the designated shop in turn using the following routes:from the entrance,successively through the bookstore,dining area, lounge,department store area,and clothing store to the makeup shop.After the participants arrived at the milk tea shop, res suddenly occurred,and the participants were required to perform the evacuation task and leave the mall as soon as possible.For evacuation tasks,we used the design between participants in 2 (spatial cognition mode:paper maps and YAH navigation maps)*2 (experimental condition:time limit and no time limit).Before the experiment,the experimenter needed to calculate the average time when the participants of the paper and YAH navigation map groups evacuated without the evacuation time limit(according to previous studies,we assumed that the evacuation time obeys the normal distribution) and calculate the limited evacuation time (the mean reduces a standard difference) as the time limit condition of the experiment.Participants in the other two papers and YAH navigation maps were evacuated under experimental time constraints.
The entire experiment lasted approximately 4 mintes-5 mintes to ensure that the participants could complete the experimental task.During the experiment,the participants used their own navigation aids to nd the way,and they all participated for the rst time and were unfamiliar with the experimental scene.The ve evacuation routes designed in the experiment are as follows:route 1 is 40 m;route 2 is 30 m,which is the shortest evacuation route;route 3 is 60 m,which is the longest evacuation route;route 4 is 42 m;and route 5 is 50 m.As seen in Fig. 2.

Experimental procedure
The main experimental procedure of this study are summarized in Table 1.Participants arrive at the laboratory to sign the consent form and ll in the basic personal information:age,gender,occupation and so on.Then,participants were required to ll in the PANAS mood scale,enter the corresponding room showing the simple virtual environment,be familiar with the use of navigation map,operate the lever and complete the relevant tasks in the virtual environment.
Then,the experiment o cially began.In the rst stage,the participants of the map group freely explored the mall and arrived at the milk tea store;the YAH map group visited the designated store under the guidance of navigation to accumulate the discount coupons in proper order.The differences between the paper map group and the YAH navigation map group participants are that the paper map group participants have greater degrees of freedom in the route decisions.
In the experiment,the experimenter needed to calculate the average time when the participants of the paper and YAH navigation map groups evacuated without the evacuation time limit and calculate the limited evacuation time as the time limit condition of the experiment.Then, participants in the other two teams of paper and YAH navigation maps were evacuated under experimental time constraints.Upon arriving at the milk tea shop,a sign saying "you've arrived at your destination,please leave the mall as soon as possible (within 33 seconds)" appeared in front of the participants.Both virtual ames and smoke occur simultaneously.
After the experiment,participants completed the PANAS mood scale again to test the participants' psychological stress before and after the trail,as shown in Table 1.Participants will then need to answer the following questions: (1) Rating the use of maps and navigation; (2) Scores the di culty of way-nding and evacuation; (3)Evaluates the vividness of virtual shopping malls.

Data analysis way-nding behavior analysis
In this study,we collected six measurements to assess the performance,mainly their walking time,walking distance and route selection in the buying and evacuation tasks.The main ndings of these data are summarized in the following Tables 3,4,5,6,7,8: First,we analyzed the walking time and walking distance of buying tasks 2 (spatial cognitive method: paper map group or YAH navigation map group) and 2 (experimental conditions:time limit and no time limit) between the participants.The results showed that there were no signi cant differences in spatial cognitive patterns in terms of walking distance of the buying task: (F(1,30)  Finally,the experimental results also show that there is no interaction between gender and spatial cognition;that is,there is no interaction between gender and spatial cognition on the walking time and distance of snatching and evacuation tasks.
We also performed an ANOVA with 2 (spatial cognition mode: paper map or YAH navigation map) * 2 (experimental conditions:time limit and no time limit) * 2 (evacuation behavior:time or distance).We investigated whether different spatial cognitive approaches and experimental conditions interacted with evacuation time.The results showed that different spatial cognition and experimental conditions interact with evacuation time and under evacuation time limit,in contrast to the participants in the YAH navigation map,participants using paper maps were evacuated at longer distances ( To test for differences in sex in experiments,we performed ANO variance on 2 (spatial cognitive mode:paper or YAH navigation maps) * 2 (experimental conditions:time limit and no time limit) * 2 (gender:male or female).Experimental results showed that neither the main effect of sex nor the interaction effect between sex and other independent variables were signi cant.

Results
The focus of this experimental study is the spatial cognitive e ciency of participants under different spatial cognitive modalities and therefore a comparative analysis between spatial cognitive e ciencies under different spatial cognitive modalities.Participants shared spatial cognition in two categories (paper maps and YAH navigation maps).First,in the analysis of path selection for participants,as shown in Fig. 6 below,path selection varies greatly between groups and spatial cognitive methods,and path selection varies signi cantly.In normal evacuation tasks,4 participants (25%) chose the shortest path 2 using the paper map,while 8 participants (50%) chose path 2 using the YAH navigation map.With the evacuation time limit,3 participants(19%) using the paper map selected the shortest path 2,while 12 participants(75%) using the YAH navigation map selected path 2, as shown in Fig. 6: In the experimental scenario of this paper,we designed the shortest path,route 2.We analyzed in our experiments that the percentage of participants using the YAH navigation maps who correctly selected the shortest route was 63% compared to participants using paper maps. Experimental results showed that participants using YAH navigation maps had more spatial cognition than those using paper maps,namely,that YAH navigation maps were more favorable to participants' access to spatial knowledge.

Subjective evacuation and analysis
We summarized all the subjective evaluations of the participants.First,we performed a mixed design ANOVA of 2 (experimental stage: before or after experiment) * 2 (experimental conditions: time limit and no time limit),which was an internal factor and experimental condition between subjects.The results showed signi cant differences in fear ratings before and after the experiment.Participants with the evacuation time limit felt more afraid after the experiment than before the experiment,while participants without the evacuation time limit group did not differ greatly in mood changes before and after the experiment.These results suggest that participants did change in psychological pressure with evacuation time limits compared to the no time limit group.We also performed a mixed design ANOVA of 2(experimental conditions:time limit and no time limit)*2(gender:male or female).Experimental results showed that female participants were more prone to changes in psychological stress than male participants.
Based on this basis,we also estimated an ANOVA of the di culty of buying task and evacuation task 2 (spatial cognitive mode:paper or YAH navigation map group) *2 (experimental condition: time limit and no time limit),which showed that different spatial cognitive methods signi cantly affected the di culty,which participants using paper maps considered harder to complete than participants using the YAH navigation map.The results also showed that for the di culty evaluation of the evacuation task,the difference in experimental conditions had signi cant effects and that participants with an evacuation time limit than no evacuation time limit participants considered a successful evacuation task harder.No other major or interaction effects were signi cant.
Finally, this paper was also tested for independence for each of the following confounders, including the degree of participants' familiarity with the VR environment and the vividness of the virtual environment.

Discussion
The main ndings and effects of this study are summarized in Table 9.This section discusses these ndings in further detail.
Effect of different spatial cognition methods on evacuation behavior.
In conclusion, the results of this study show that the participants of paper map groups walk for a long distance and time during buying tasks.YAH navigation maps can save subject cognitive resources 64 .Participants using paper maps require intensive,complex spatial knowledge acquisition and processing processes.This is consistent with the conclusions of Kruger and Munzer,where mobile navigation techniques better communicate landmarks and routes to users for route nding compared to traditional maps.In addition,during the experiment,the YAH navigation map group tried to follow the planned route of navigation,so it was shorter than the average length of the route of the paper map group.This is demonstrated by a review of the experimental video,with a detour or return of 19% (6 of 32) in the paper maps,causing them to spend more time on the longer route completing the buying task.
The results also show that the paper map group participants walked longer in the evacuation task than the YAH navigation map group participants and considered the task more di cult.The main reason for this difference between the two groups of participants is as follows: rst,the goal of the evacuation task.The goal in this study is to nd the mall exit.In the evacuation task,the participants do not need a complete space cognitive map,and the space knowledge related to the exit location is su cient to help participants nd the exit of the mall.Cao Li jun and others also found that participants with some spatial knowledge tended to evacuate through the routes they were familiar with.Second,participants exploring the space along the route speci ed in the YAH navigation map do not need to compare the spatial representation on the map with the environment to nd the speci ed location.They can follow the realtime guidance of the navigation map and maintain a relatively stable forward direction,the direction of the exit.Finally, in the experimental process,the paper map group participants may go in the wrong direction,circle or return behavior,causing confusion regarding spatial cognition.In summary,in the case of indoor re bursts,the YAH navigation map is more conductive to guiding people's emergency evacuation behavior.

Effect of the experimental conditions with evacuation restrictions on the evacuation behavior
The results of this experiment also show that the participants spent more time searching out the mall exit and considered the evacuation task more di cult.These results are consistent with those of Cao Li jun (2019),etc.,where participants in re emergency conditions escape longer than participants nding exits in normal conditions.These ndings indicated that the evacuation time limits had important effects on the participants' evacuation performance during the evacuation task.First,the participants produced a stress psychological response to re incidents and felt more scared after the experiment than before the experiment 66,47 .People in re emergencies have greater physical and psychological stress,different perception patterns,different behavior patterns,and poor road-nding ability 45 .
Proulx's pressure model (1993) also shows that people will feel fear or stress in the face of a sudden re.In this paper,we control people's psychological stress by controlling evacuation time and nd that participants have greater psychological pressure in the time limit compared to participants in the no timelimited group.There was a signi cant increase in pressure in the time-limited compared to participants in the no time-limited group.A signi cant increase in pressure creates a high pressure stats that limits people's ability to deal with environmental information effectively 45 and leads to a decrease in evacuation e ciency.
Meanwhile, the results also showed that there was no signi cant difference in the walking distance of the successful evacuation.This suggests that although the presence of evacuation time limits can affect the subject's ability to perceive and process environmental information,these restrictions do not affect their ultimate success in nding the right route to the exit.
Finally,we nd that the experimental conditions with evacuation time limit have no signi cant effect on the vividness of the virtual environment and the participants' familiarity with the virtual environment.Therefore,it can be shown that the differences in the trial times in this study were not caused by individual differences.
Effect of different spatial cognition methods on the spatial cognition e ciency Participants in paper map groups varied signi cantly in the choice of paths.Using paper maps, 7 people selected path 2 (22%);the YAH navigation map group subjects also differed signi cantly in path selection,with 20 people selected path 2 (63%).In this paper,we control for factors such as gender,population density and spatial cognition within the two groups and consider only the different route selection between groups.Experimental results show that the YAH navigation maps choose the shortest route (22% vs 63%) compared with the participants in paper maps,namely,the YAH navigation map is more conducive to obtaining spatial knowledge about the environment and improving people's spatial cognitive e ciency of the environment.This is inconsistent with the results of Golledge and Aslan that technology-assisted routing reduces spatial knowledge gained compared to more traditional pathnding methods such as using paper maps.

Limitations
There are some limitations in the study of this paper,which can be corrected in future research.First,the experiment only considered the impact of two spatial cognitive methods on people's ability to explore roads in re.Due to the lack of research on other spatial cognitive methods,other spatial cognitive methods can be studied in the future.Second,the number of participants is limited,so the results are not very representative;expanding and including human age and expertise will be a good choice in the future.Finally,way-nding is a complex cognitive process,and each of these steps may be affected by spatial cognitive methods and re emergencies. In the future,it will be possible to study the in uence of dynamic changes in re on way-nding behavior.

Conclusion
Our study demonstrated several conclusions.First,the YAH navigation map is more bene cial to guide the behavior of emergency evacuation.Second,the YAH navigation mapping group is more conducive to obtaining spatial knowledge about the environment and improving people's spatial cognition e ciency of the environment.Finally,psychological stress will limit people's ability to effectively process environmental information and reduce evacuation e ciency. Tables   Table 1 Experimental procedure   Table 2 The Experimental groups         The waking distance and walking time of different spatial cognition methods

Figure 5
Walking distance and time of different experimental conditions Figure 6