4.6. Spatial Knowledge Acquisition and Cognitive Maps

In this section, two experimental tasks that attempted to measure the amount of spatial knowledge that had been acquired while performing the field test are examined.  Much has been written about spatial knowledge acquisition and the creation and use of mental or cognitive maps regarding people with severe visual limitations.   For a review, see such authors as Dodds, Howarth, & Carter (1982), Foulke (1983), Golledge (2001), Golledge, Blades, Kitchin, & Jacobson (1999), Golledge, Kitchin, Blades, & Jacobson (2001), Golledge, Klatzky, & Loomis (1996), Jacobson (1993), Kitchin (1994), Kitchin & Jacobson (1997), Lockman, Rieser, & Pick (1981), Long, Rieser, & Hill (1990), Passini (1986), Rieser, Guth, & Hill (1986), Strelow (1985), and Thinus-Blanc & Gaunet (1997) .
 
Despite these reviews and many experiments, there is still little agreement on how blind people perceive, learn, understand, and internalize geographic spatial information.   However, these research reports do uncover information about knowledge structure and content and allows for measurement of some kind of “accuracy” compared to the real environment.   Results from the following two experiments demonstrate the lack of agreement about the skills of people with various degrees of visual experience.   An elegantly crafted experiment showed the effect of specific visual knowledge (blindfolded sighted), previous general visual experience (adventitious) and no visual experience (congenital).   Subject made comparative distance judgments between groups of three named locations (choosing the two that were closest and the two that were furthest apart).  The data showed that, when making distance judgments through walls (as the crow flies), those with no previous vision experience had the most error, those with specific visual knowledge of the layout had the fewest errors, and those with previous visual experience, before losing their sight, fell between those other two groups (Rieser, Lockman, & Pick, 1980) .  Another group of researchers also tested blindfolded sighted, adventitious and congenitally blind people.   Those subjects performed various physical tasks, such as retracing a multi-segment route in reverse, returning to the origin after being led around linear segments, and pointing to targets after locomotion (Loomis et al., 1993) .  In contrast, they found little indication that prior visual experience influences spatial competency.   These differing results can be explained, at least partially, through a closer examination of the subjects and methods.    Rieser et al. tested four subjects in each group, they were all very familiar with the layout, the blind subjects were in the process of receiving blind skills training, and the test was a non-physical recollection of previous knowledge.  In the Loomis et al. experiment, 12 subjects were in each category, they were more independent as travelers, they had no previous knowledge of the environment, and the layout was physically experienced during the test.   This brief summary of two well conducted experiments show some of the reason for differences in theories relating to the skills of people with blindness. These different theories are discussed later (see Section 7.2.1 , Relevance of this Work to Spatial Organization Theories of the Blind ). 
 
The intent of the present research is not to add to the wealth of literature about how spatial information is processed and stored into the cognitive map of the blind user.   Rather, the focus is on examining what can be learned about the source of restrictions that affect travel and accessibility for the blind.   At its core, spatial knowledge acquisition and cognitive map accuracy is a primary concern because these have some utility to the user; the more accurate an individual’s spatial knowledge and mental map, the easier it would be for a person to navigate an environment and gain access from one location to another.   In this section, how the utility of the subject’s knowledge is shown through active field tasks in navigating a new environment is examined.  
 
In the field tests, the blind subjects using RIAS were significantly faster and more efficient in navigating and finding their destination goal than without the system.   To navigate in a new environment, people must actively orient themselves to an object or location destination and proceed toward it.   But, just as a sighted person might be able to complete many path segments and still not acquire a good spatial representation of the area, the navigation accuracy and efficiency, exhibited by RIAS users, does not necessarily mean that spatial knowledge has been acquired, processed, and stored. 
 
Sholl (1996) argues that there are two processes used for successful acquisition and understanding of spatial layouts.   People must understand not only the dynamic person-to-object relationships that occur when navigating a route, but also the stable object-to-object relationships that are anchored in the environment.   Object-to-object relationships can be quite difficult for the blind because there are no visual cues or distal vistas providing knowledge of the spatial arrangement between objects.   In addition, optic flow cannot be accessed to monitor the changing relationships of objects while in motion.   This is why some blind people, though well trained to follow a path, might not easily understand the environment’s spatial arrangement - the relationship between all objects - and might be ignorant of entire sections of space.   For some blind people, any deviation off a known route is “terra incognitae,” and sticking to a known route is the safest, most secure, and, therefore, “optimum” option.   This means that one might have learned and be able to walk a path from A to B and then to C but have little idea how to go from C to A without retracing the route, back through B.  People with limited or no vision might not have a good idea of the object-to-object relationship between C and A, and this task of making “shortcuts” is made even harder because a blind person might have no idea of what type of environment or terrain lies between C and A.   Therefore, potential barriers, obstacles, unsafe surfaces, and general fear and apprehension about new environments restrict some blind people to known routes and locations.  
 
Since cognitive maps are an internal process, there is no way, as yet, to access and analyze them except through measurement of surrogate and externalized methods.  There appears to be no precise and accurate correspondence between internal spatial knowledge and what can be discovered through the use of these externalized measurements or spatial products.   For more information on externalized spatial products , see Golledge (2001) and Kitchin & Jacobson (1997) .  The use of various spatial products can lead to different observations about an individual’s cognitive map.   This problem is evident in the wide range of theories regarding spatial knowledge acquisition for people with vision restrictions.   When different results are found using different spatial products, it makes it difficult to know which measure is “correct.” This produces weak convergent validity, but, when several spatial products reveal similar results, stronger convergent validity is evident.
 
To increase this methodological validity, subjects’ cognitive maps and spatial knowledge (using two different kinds of spatial products ) were examined.   A wayfinding and navigation product was used when subjects were given the opportunity to make several shortcuts in the field test.   The other method used was to examine cognitive maps by asking questions about object-to-object spatial relationships, with a verbal description product, using a simple sentence framing technique.   The verbal description experiment is discussed later in this section.  
 
Every attempt to uncover the internalized map knowledge by an external product has correlation problems.   Using navigation tasks is no exception, and they also add confounding factors.  Subjects might use environmental cues, in addition to their spatial knowledge, to guide their action.   On the other hand, well-controlled laboratory experiments might have less noise, but they can raise questions of external validity.   For example, is the relationship between objects on a tabletop experiment actually relevant to the person or theory being studied?   Can those results be extrapolated to real-world or geographic spaces?   When considering the important tasks of understanding how the blind perceive, learn, and, especially, use real-world space, much can be said for tests that reveal spatial knowledge that exhibits a high degree of usefulness or utility to the people being studied.    

4.6.1. Spatial Knowledge Revealed by Navigation and Wayfinding Tasks

Chapter 3 discussed two of the field transfer tasks where subjects were allowed to take any route they chose to locate the next task destination.   Figure 3.5 shows the routes taken for transfer task 3 and the location of the RIAS transmitters.   There was occasional construction activity , and therefore subjects were guided by the researcher out the front door of the terminal and turned left toward Townsend Street.  They turned left again and walked down Townsend to a cabstand on the street.   No information was given about street names or turn direction; subjects just walked along with, and were guided by, the researcher.   Subjects were then told to find the water fountain in the terminal.   No additional path information was given.   The terminal had side doors facing Townsend Street that led into the station, and these doors were labeled with RIAS transmitters.   No mention had been made of these doors.  
 
To eliminate variance and noise in the data, only those subjects who had no residual vision are reported on.   None of those could see shapes, or objects up close.   There were 20 such subjects in the sample of 30; 11 subjects used their regular method for their first trial at the terminal, and nine used RIAS for their first trial.
 
Air currents and crowd noise might have been available as cues for the blind to enable them to notice or locate the doors to the street.   For the 11 blind subjects that used their regular methods first, only three (27%) made the shortcut through the side doors.   The rest retraced the longer path they had previously taken to the cabstand.   In contrast, all nine (100%) of the blind subjects using RIAS on their first trial used the shortcut.  Although they had not been looking for the door, they appear to have learned about it while scanning around during the previous or current tasks.   No formal data was collected, but the researcher noticed that some subjects heard the side door message while they were looking for Track #2 (in the previous sub-task), after leaving the track door on the guided walk, or from the outside while going to the cabstand.   It was also possible to hear the message while starting to retrace the original path if they were scanning in that direction.   Table 4.12 shows the data for both possible shortcut trials (subjects using NRIAS 2nd did not perform these tasks).   It also shows the results for the within subject condition where subjects tried RIAS on their second trial.   Results for the subjects who reported they could see shapes and objects up close are also shown, along with the total for all 30 subjects.  
 
The second route where a shortcut was possible occurred after subjects visited Track Door #11 at the far end of the terminal.   See Figure 3.7 for the diagram of that route.  From that door, they were told to go to the street corner that had first been visited, but to prepare to cross the other street.   Again, no street names or directions were given.   There was a series of doors across from the track doors that led to a plaza opening up to the street.   This is the kind of situation where, even if a blind person knew there were doors available, they would not know what was outside the doors, or whether they could get to the corner without barriers or obstacles in the way.   Only two (18%) of the eleven blind subjects, in the first condition, used the shortcut through the doors leading to the outside plaza; the others all walked back down the hall in the opposite direction and went out the main exit that they had learned in the first task.   For the nine blind subjects that used RIAS first, eight (89%) used the door opposite the track door to directly access the corner.   The RIAS transmitter above the door had the message, “Exit to 4 th and King plaza.”   They must have found this message while scanning around the environment (either while walking to Track #11 or when starting the trip to the corner). The message, giving the direction and identity of the doors, appeared to provide them with enough information to attempt navigation in a totally new area of the environment (the plaza area).  
             

Table 4. 12   Ability to Make Shortcuts

 

Cab-stand to

Water Fountain

Track Door #11 to

Corner of King and 4th

 

Regular

Method

1st

Using

RIAS

2nd

Using

RIAS

1st

Regular

Method

1st

Using

RIAS

2nd

Using

RIAS

1st

No

Vision

N = 11

N = 11

N = 9

N = 11

N = 11

N = 9

27%

91%

100%

18%

64%

89%

Some

Shape

N = 2

N = 2

N = 4

N = 2

N = 2

N = 4

100%

100%

100%

0%

50%

100%

Some Objects

N = 2

N = 2

N = 2

N = 2

N = 2

N = 2

50%

100%

100%

50%

100%

100%

             

All

Subjects

N = 15

N = 15

N = 15

N = 15

N = 15

N = 15

40%

93%

100%

20%

67%

93%

 

The propensity to make shortcuts and the spatial knowledge awareness exhibited here is a true measure of the utility of their cognitive map.   Being able to make shortcuts shows an understanding of the object-to-object spatial arrangement and the ability to make efficient route choices, which is the goal or utility of a good mental representation of an environment.   The literature (see above citations) and statements from blind people state that making shortcuts is difficult, and that some people retrace their steps rather then try to figure out if it is possible to take a new route through the environment.   As in the case of a vision-impaired person’s impedance to making transit transfers (see Section 4.5.1 , Impedance Considerations while Making a Transfer Decision ), they would rather stay with a known environment rather then risk obstacles and barriers in a new environment, thus avoiding apprehension and stress.   This inability to access the “best” path is a major restriction to access in new environments and limits independent travel and learning spatial arrangements efficiently.   Instead of being taught a new path by a friend, stranger, or O&M instructor, blind people using RIAS appear to learn an environment on their own and access the environment in the way that it was designed.   An additional benefit of using a system like RIAS is that a person can learn about locations they were not even looking for.   The existence of the doors that were used for the shortcuts appear to have been learned while performing previous, unrelated tasks.   Subjects did not actively search for a shortcut when presented with the next destination; rather, they had already learned and stored that information while doing other tasks.   User comments reported during the experiment also verify how important this ability to discover new knowledge is to the blind.   They are able to learn new environments and locations without having to stick to a known path, follow other people, or ask for help.   Subjects often mentioned “independence” in their comments, and the ability to learn new environments without help and the ability to make shortcuts are major sources of this feeling.   
 
For the two shortcut tests, blind people using their regular method on their first attempt had 22 chances to make a shortcut, and only five times (23%) were subjects able to take full advantage of the potential accessibility in the environment and use the shortest path.   When using RIAS, first time subjects had 18 chances to use a shorter path, and all but one (95%) did so.   As an objective measure of accuracy in navigation, the ability to reduce distance by making correct spatial decisions is fundamental.   RIAS demonstrated its ability to save distance and time for subjects in new environments, making it easier to gain access to more activities.    

4.6.2. Spatial Knowledge Revealed Through Verbal Statements

Another way to measure cognitive map knowledge is to examine spatial products revealed by verbal or written descriptions.   A type of sentence framing technique was used where subjects were asked to give the answers to a series of 20 questions that dealt with both spatial arrangements and knowledge of the environment.   Questions that dealt directly with spatial relationships between concession stands and the ticket window and with relationships between amenities in the waiting room area were used.   Other questions dealt with the spatial arrangement of the track doors, information about the traffic lane configuration of the streets they crossed, names of the streets, and other more general spatial relationships in the terminal environment.   To reduce variance and increase validity, only the subjects who had no useful vision are reported on.  
 
The spatial questions were asked after five transfer tasks were completed, in the NRIAS 1st , NRIAS 2 nd , and RIAS 1st conditions.   Subjects were walked outside the station and rested on a bench facing away from the station to eliminate any cues about the questions that followed.   Subjects had not been told that any spatial questions would be asked and so had no way to cognitively prepare for a spatial test.   The questions were given in such an order that no previous question could give the answer to any further question (see APPENDIX 4 : Subject Questionnaire for San Francisco RIAS Experiment ).  Of the 20 questions asked of the 11 subjects with no useful vision using their regular method on the first trial, 44% were answered correctly.   When these same subjects used RIAS on their second trail, the mean number correct rose to 84%.   In comparison, the nine subjects who used RIAS for their first attempt in the field test got 88% correct.   The use of RIAS was highly significant; the difference between the blind group using their regular method and using RIAS on the second try was (p<.0001) and, when compared to the RIAS first condition, was (p<.0002).   Those using RIAS first actually had better results than the group who used it second, but the order of the condition had no significance (p<.56).    

4.6.2.1. Frequency Distribution of Spatial Knowledge Performance

The frequency distribution of each person’s correct scores in their first trial, between the two groups, was highly skewed in favor of those using RIAS.   The worst scores per subject, out of 20 questions, for those using their regular methods, were two twos, a four, and a five.   The best scores for that group were a 13, two 14’s and a 15.   In contrast, the worse scoring two subjects using RIAS in their first attempt got 12 correct.   Six subjects missed only one question (19 correct), and one person got all 20 questions right.  What made this even more remarkable was that the control, the first time sighted user (FTSU; see Section 1.6.6 , Sighted Subjects for Baseline )got just 16 (80%) correct.   RIAS gave so much information that seven of the nine blind subjects using RIAS first scored higher on these questions than the first time sighted user.   Figure 4.10 shows the frequency distribution of each subject’s correct answers on their first trial, a measure of their spatial awareness.
 

Figure 4. 10   Frequency Distribution of Spatial Awareness


4.6.2.2. Frequency Distribution of Answers to Spatial Questions

The distribution of how well each question was answered was highly skewed toward the RIAS condition.   The three “easiest” questions were answered correctly in the regular method condition by 73, 73, and 82 percent of the subjects.   In contrast, the three hardest questions for RIAS users, after their first field trial, were answered correctly by 67% of the subjects.   Eight of the questions were answered correctly by 100% of the subjects, and another five questions were missed by just one subject when using RIAS.   In the within-subject condition, all regular users scored better after using RIAS.   One person answered an additional 13 questions correctly, another 10; three got nine, and two more got eight more correct on their second trail with RIAS.   For each of the 20 questions, those who used RIAS first scored higher than those who used their regular method first .  Table 4.13 shows the questions numbered and ranked from hardest to easiest in the blind regular condition. 

A variety of different questions was asked, and the next section will discuss these various groups of spatial and information questions.   It is difficult to use externalized spatial products to accurately measure the internal cognitive map.   The main interest here is how that map has real utility for blind travelers, which information is the hardest to learn without vision, and how these gaps in the cognitive map can affect independent travel and accessibility.   Using a mixture of question types removes bias caused by the researcher’s choice of the “correct” way to measure the internalized map and lets the subjects more clearly speak to the contents of their cognitive map and reveal which tasks are difficult to master.  

Table 4. 13   Spatial Question Analysis

Spatial Questions

Trial #1

Regular

Method

Trial #1

Using

RIAS

Type

Q #

 

Percent Correct

   

Which track # did we first start at?

9

78

BI

1

Where do the doors across from tracks 9-12 lead?

18

78

BI

2

What street is the taxi stand on?

27

67

SN

3

What street did you cross to get to the Muni rail platform?

27

100

SN

4

What street is in front of the train station?

27

100

SN

5

How many train tracks serve the Caltrain station?

27

100

BI

6

Which tracks are closest to the waiting room?

27

67

TS

7

How many lanes and what direction (one way / two way) is this street [to the Muni rail platform]?

27

89

SI

8

Which tracks are closest to the main entrance?

36

67

TS

9

How many lanes and what direction (one way / two way) is this street [in front of the train station]?

45

78

SI

10

Which track door # is closest to track door 7?               

45

100

TA

11

Which track door # is closest to track door 6?               

55

100

TA

12

What concession counter is closest to the train area?

55

89

CS

13

Which concession counter is closest to or across from the ticket window?               

55

100

CS

14

What amenity is closest to the phone?

55

100

AS

15

What amenity is furthest from the phone?

55

89

AS

16

The highest track # is closest to which of the other transit modes we visited

64

78

GS

17

Which amenity is closest to the water fountain?

73

89

AS

18

Which concession counter is closest to the front street?    

73

89

CS

19

What concession counter is closest to the Candy counter?

82

100

CS

20

Mean correct spatial questions

44

88

   

4.6.2.3. Cognitive Map Knowledge And Spatial Awareness In A New Environment.

The question types and answers in the general order they appear on the table, sorted from hardest to easiest to learn, are discussed.   The order was determined by the answers of the people using their regular methods of navigation.
4.6.2.3.1. Building Information (BI) Questions #1, 2 and 6
Only one blind subject answered the hardest question (#1) using regular methods of orientation.   Even our FTSU (control) did not know the answer.   Subjects were walked to the beginning location of the test with their eyes closed and started with their back to the door.   There was little utility in knowing where they started from and few cues available to gain this knowledge.   With RIAS, subjects got this question right 78% of the time.   The next hardest question (#2) asked about the doors across from tracks 9-12 and where they led.   Only two (18%) subjects knew the answer without RIAS.   Since most of the regular method subjects did not even use these doors (for the shortcut) they had little knowledge that the doors even existed.   With RIAS, 78% knew the correct answer.   The other question put in this general building information group was #6, asking for the total number of tracks at the station.   The highest track number actually visited was #11 and, without knowledge of the track layout and extent of the hallway, there were few ways to know the correct answer.   For the regular orientation group, three people (27%) knew there were actually 12 track doors.   All subjects using RIAS got that question correct.   These three questions asked about information that was not directly needed to complete the field test, and the results show that this information was not learned by most of the regular method subjects.   Those using RIAS picked up this information quite well, even though it was not critical to the task and they were not required to navigate to those locations.  This ability to pick up information about locations while doing other tasks is often impossible without sight, unless an active and physical search is undertaken.   To be able to learn about the environment while simply walking through it is what vision allows, and this ability to easily gather spatial information helps make sighted navigation so much more efficient.  
4.6.2.3.2. Street Names (SN) Questions #3,4, and 5
The names of the streets were never mentioned during the experiment, although some subjects certainly learned them before making the trip to the Caltrain station.  Street names are also not necessary to make successful locomotion but can add enormously to general spatial understanding and the ability to make crucial spatial decisions.   Questions 3, 4, and 5 all dealt with the names of the three streets, and, for these questions, only three people (27%) got them right without the orientation and identity help provided by RIAS.   The control (FTSU) also did not know the names of the three streets.   For the street they did not cross (Townsend), 67% of the subjects got that question correct after using RIAS.   They likely learned that name while scanning toward the side (shortcut) doors.   Subjects crossed 4th and also King Street, and, with RIAS, they heard the name of the street being crossed while they waited for the “WALK” message.   All subjects using RIAS knew the correct answers for those two questions.   There is little doubt that, although not necessary for successful locomotion, knowing the names of streets in the environment helps spatial decision-making and spatial orientation and adds to general knowledge and peace of mind.    
4.6.2.3.3. Tracks, Spatial (TS) Questions #7 and 9
Two questions, 7 and 9, asked about the relationship between track doors and other locations in the terminal building.   Of those using their regular orientation skills of orientation, only three (27%) knew which tracks were across from the waiting room, and four (36%) knew which tracks were closest to the main entrance hallway.   When using RIAS, subjects got both of those questions right 67% of the time.   Again, this knowledge was relevant, but not critical, for the navigation task, but the higher scores show that the use of auditory cues gave better spatial knowledge of the environment.   It is quite difficult for blind people to get enough distal cues to understand the relationships between locations in a large open space.   With no visual cues to spatial arrangements, blind travelers must often go to a wall and search along it until finding a location.   Later, they might be at the opposite wall to find other locations.   If the open space between these two locations is an area that is too large to comprehend without vision, they might have little or no knowledge of the spatial relationship between the two locations.   The two locations might even be directly across from each other, but this knowledge can be hard or impossible to acquire, at least without much physical activity. 
4.6.2.3.4. Street and Lane Information (SI) Questions #8 and 10
Crossing streets safely and successfully requires gaining information from various modalities.  One listens to traffic sounds and tries to determine the shape of the intersection, traffic flow and speed, lane direction, and turn lane cycle information.   Two questions (8 and 10) asked about the two streets that were crossed in the experiment.   They asked about how many lanes the subjects had crossed and whether they were one-way or two-way streets.  The regular users got 27% and 45% of these two questions correct, even though they crossed each of the streets twice.   RIAS users got 87% and 78% correct on the same two streets.   This information is not mandatory for successful locomotion, but the knowledge certainly adds to the safety and success of a street crossing.   For instance, not knowing that a street is one or two ways or has an extra turn lane could lead to serious accidents or death.   It also helps to know lane and direction information in advance so that one can know what to listen for while waiting to cross the street
4.6.2.3.5. Track Arrangement (TA) Questions #11 and 12

Figure 1.1 shows the twelve tracks serving the Caltrain terminal.   Tracks 1 and 2 are separated by a wide concrete shared boarding platform, and this pattern is repeated up to the final shared boarding platform for tracks 11 and 12.   There are two sets of double doors that open from the terminal onto each shared platform.   Thus, doors for track 1 and track 2 are directly next to each other, while track 3 is quite a distance away (where it is next to the door for track 4).   The spatial arrangement of the doors and tracks is not easily discernable without sight.   Two questions were asked to determine if the subjects had learned the spatial arrangement of the track layout.   Questions 11 and 12 asked subjects to state which track door # was closest to another.  The people using their regular skills got 45% and 55% of these two questions correct.   Even after visiting various track doors three times, about half still did not show knowledge that the doors were arranged in groups of two (with the odd number door on the right and the even one on the left).   This is critical information needed to make efficient navigation and full use and access of a train terminal.   With the use of the information provided by the auditory and directional cues, 100% of the subjects knew that the doors were arranged in groups of two, so that track #8 was closest to #7 and track #5 was closest to #6.   There is a high utility associated with having this type of information.   Since there was no Braille or tactile information on the doors, it could have taken quite a while for a blind person to understand this arrangement and extrapolatethis arrangement to all platform doors in the current environment.

4.6.2.3.6 Concessions, Spatial (CS) Questions #13,14,19, and 20

During the field test, subjects visited all three concession stands and the ticket window (twice) in the main hallway.   The person-to-object information they acquired while walking to these locations appears to have been formed into a better object-to-object understanding than other types of locations.   For questions 13 and 14, subjects using normal orientation skills got 55% of those questions correct.   In contrast, with RIAS, one of the questions was answered correctly by 100% of the subjects, and the other question had one incorrect answer (89%.)   Regular users answered 73% and 82% of the other two questions about the spatial arrangement of the concession stands correctly, and, with RIAS, they scored 89 and 100% respectively.   Clearly, the active search and navigation allowed subjects to understand these types of spatial relationships better than some of the other types of locations.   The area between the four locations was quite small and fairly easy to understand.  

4.6.2.3.6. Amenity, Spatial (AS) Questions #15,16, and 18
Each of the subjects visited three amenities in the waiting room during the field test.  They found the “correct” bathroom, the phones, and the water fountain.   This was a very small area; the locations were just a few feet away from each other, although they were on three different   (90 degree separation) walls.   Although these locations were almost touching each other, only 55% of the normal orientation subjects were able to identify what was closest to the phone and also what was furthest from the phone.   RIAS users scored 100 and 89% on those 2 questions respectively.   Regular navigation subjects scored 73% when asked what was closest to the water fountain, and RIAS users scored 89% on that question.    
4.6.2.3.7. General Spatial (GS) Question #17
There was one question that did not fit any of the groups.   It dealt with not just the terminal but with the entire area that had been navigated, including the cab stand, the bus shelter across 4 th Street, and the Muni rail station across King Street.   The question asked subjects to identify which transit mode was closest to the highest track # at the terminal.   The Muni rail station was directly across one sidewalk and two lanes of traffic from the highest track number.   The cab stand and bus shelter were much further away.   RIAS users got this general spatial question correct 78% of the time, and, without the system, subjects got this correct 64% of the time.   Results on this question were probably confounded by some subjects not considering closest to mean “as the crow flies” distance.”

4.6.3. Summary of Spatial Knowledge Acquisition and Cognitive Maps   

A researcher using some type of externalized means of measurement must extract the information stored in a person’s cognitive map.   Different spatial products are likely to reveal differing amounts and types of information.   Two methods were used to gain more convergent validity and concentrated on testing if these observed internalized spatial representations had utility for the user.  
 
  • Except for one trial, all subjects using RIAS (95.5 correct) were able to identify unvisited doors and make a successful shortcut to the next destination.
     
  • With their normal methods, all but 3 attempts (23% correct) led to making the longer (retrace) path, not having the knowledge to make a shortcut.
     
  • RIAS allowed users to find information they were not actively searching for and use it later to affect more efficient travel.
     
  • All 20 spatial and knowledge questions were answered correctly by more people when using RIAS.   There were many incorrect answers for the regular users; and most RIAS users scored exceedingly well.   In fact, 78% of the RIAS users scored better than the fully sighted first time visitor (control).  
     
  • Regular navigation skills led to higher correct scores for spatial locations that they had visited quite often.   The best results were those associated with the relationships between concession stands and the ticket window, the amenities in the waiting room, and the general layout of the entire site.   All these types of places were visited multiple times, and this helped increase their accuracy.  
     
  • Subjects that used their regular orientation skills had little success incorporating knowledge about places that they did not actively visit.   They had difficulty knowing the names of the streets that they had used and also the information about the streets’ characteristics.
     
  • Subjects without RIAS also had trouble understanding the arrangement of the track doors, even after 3 visits.  
     
    Cognitive mapping research concerned with blind travel provides information on what restrictions exist and what cues are missing.   It allows the testing of assistive devices against known behavior and spatial awareness.   These two experiments, assessing subjects’ ability to make shortcuts and spatial knowledge, provide information about how hard it is to learn spatial information without vision, unless the area is accessed repeatedly.   Blind users trying to navigate unknown spaces can be at a great disadvantage, and that affects their ability to have ready access to many new environments.   Many cannot easily, efficiently, or independently learn new environments without much effort or training.   This incomplete spatial knowledge affects the ability to gain reasonable access and could be a reason why many blind people report very limited travel behavior or never venture out alone.   Even with multiple visits, spatial relationships remain elusive for some.   The ability to increase one’s spatial knowledge with auditory signs, by providing easy access to missing directional and identity cues, allows for independent and dignified wayfinding.   These auditory cues allow blind users to gain some of the critical spatial information that a sighted person can access, and they allow for efficient behavior such as the ability to make shortcuts and learn the layout of an environment.  
     
    By comparing cognitive mapping results of an assistive aid such as RIAS to the regular method baseline, much needed knowledge is gained about what cues are needed and how to best present these navigation cues to a user.   These two tests provide evidence that, with the availability of additional cues giving direction and location identity, blind people can form an accurate cognitive knowledge of an area just as well as a sighted person.  They can learn locations without visiting them and are able to use this knowledge (utility) to take advantage of the access potential of an environment, something that has previously been denied to them.   This empirical evidence should put to rest the notion that there are inherent flaws in the ability to acquire spatial knowledge without sight.   Blind people appear to have the processing ability required to understand geographic space, and it is the lack of accessible cues that can cause inferior spatial knowledge.   It appears that RIAS provided essential spatial information that was mostly lacking, thus allowing blind travelers to use spatial skills that are otherwise suppressed.
     
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