- Email: [email protected]
Computerized Assessment of the Ability for Transformation of Visual Mental Images
IFAC DECOM-TT 2004 Automatic Systems for Building the Infrastructure in Developing Countries October 3 - 5, 2004 Bansko, Bulgaria
COMPUTERIZED ASSESSMENT OF THE ABILITY FOR TRANSFORMATION OF VISUAL MENTAL IMAGES
Anelia Popandreeva Bulgarian Academy of Sciences - ICSR
Abstract. Transformation of visual mental images according cognitive theories is a subprocess of view imagery. Software test for asseement of the ability for mental rotation includes 24 tasks. Each of them consists of 5 figures, one of wich is a mirror figure of other. The tested person has to discover the mirror figure. The software is designed in two versions for running on any IBM-compatible personal computer operating under MS-DOS or Windows. Object-oriented approach for development of the software has been applied. Classes and their relationships are described. . Copyright © 2004 IFAC Keywords: Diagnostic tests, Object- Oriented Programming.
INTRODUCTION Transformation of visual mental images according cognitive theories is a sub-process of view imagery. Mental rotation is a basic transformation. It is a part of many tests (Biederman, I., 1994). In the first test for assessment mental rotation stimuli are letters in normal and mirror position. The tested person has to rotate them mentally to upright position. In the following tests stimuli are changed with digits, symbols or forms. 1. ASSESSMENT OF THE MENTAL ROTATIONS OF FIGURES IN 2D SPACE Test procedure includes 24 sets of stimulus. Stimuli are digits, letters and figures. Each set consists of 4
figures and one mirror figure. They are rotated on different angle (Terzieva, M et al. 1996). For the assessment has been developed computerized test. Test begins with instruction for the tested person. It is followed by an example. After that 24 tasks are presented to the tested person in the same order. Each task consists of 5 figures and the tested person has to discover the mirror figure in this set (fig.1). The time for visualization of the stimuli can be defined before beginning the test procedure. The true answers are weighted with 1 and false answers are weighted with 0. The software test records each answer and time for them for each task. After that it calculates the number of answers for different tasks and its percent of all answers (fig.2).
2.1. Requirements for computer test Test consists of 24 sets of figures. Each set includes one figure rotated in four different angles and one mirror figure. Each of the figures is drown of sequence of seesaw lines and/or arcs. Each set is visualized and the time for answer is calculated. Answer has to be defined as true or false answer. Test has to have ability for limiting the time for test procedure. Before testing identification data for tested person have to be input and saved. Test has to begin with instruction and example. Report of the test has to include personal data, time for test, and number of true answers, type and time for each answer.
Fig.1. Mental rotations in 2D space Rotation Number Years:
Name
On figure 3 is shown diagram of basic elements of the computer test.
True answers - 12 -> 50 % Time for test -
0 min
1+ 2+ 3g 4+ 5g 6g 7+ 8+
17 g 18 + 19 g 20 + 21 g 22 + 23 g 24 +
3.03 sec 1.92 sec 1.04 sec 1.54 sec 0.77 sec 1.04 sec 0.82 sec 2.09 sec
9+ 10 g 11 g 12 g 13 + 14 + 15 g 16 +
0.93 sec 0.82 sec 0.82 sec 1.16 sec 1.43 sec 0.77 sec 0.99 sec 0.83 sec
26.26 sec 0.77 sec 0.93 sec 0.61 sec 0.77 sec 0.66 sec 0.60 sec 0.87 sec 1.05 sec
Person Data
Instruction
Figure
Answer
Timer
Report
Fig.2. Report of the test. 2. OBJECT -ORIENTED APPROACH FOR DEVELOPMENT OF THE SOFTWARE Object-orientation is a technique for development of software organized as a number of objects that interact. Among the most benefits of designing the software with object-oriented approach is understanding, moulding the problem domain more naturally, developing the software systems from reusable modules, using the programming languages, which are close to the solved problems and which allow efficient user-defined types, and information hiding (Booch, G, 1991). The most popular objectoriented design methods are Booch (Booch, G, 1991), OOSD ( Wasserman et al., 1990), and HOOD methods ( HOOD, 1989). Booch’s method is one of the best-worked-out design methods. It is not tied to programming language. It has very reach notation of structure. A convergence of object-oriented methods led to the unified modeling language ( UML) notation ( Booch et al., 1999). Computerized test for assessment of the ability for transformation of visual mental images has been designed with Booch’s method.
Fig.3. Basic elements of the test 2.2. Design Proceeding from the requirements it is possible to define key abstractions PersonData, Instruction, Timer, Figures( Stimuli), Answers. Logical structure of the system is presented with class and object diagrams. During development the software tool classes PersonData, Test, Figure, Answers, Instruction and Stimuli have been designed. Class Test organizes the test procedure. It consists of (uses) classes PersonData, Instruction, Stimuli and Answers. Class PersonData includes member-variables and member-functions for identification of the tested person. Class Test includes variables and functions for running the picture test, for saving and printing the results from the test. Class Instruction includes functions for introducing the tested person to the test procedure. Class Stimuli consists of( uses) class Figure. Class Figure includes variables and functions for initialization and drawing 5 figures. Class Answers saves time for answer and defines type of answer – true or false. Class Timer registers times for test and
for each answer. Classes Timer and Answers are connected through functions friends. Figure 4 shows class diagram for developed test. Figure 5 shows notation for the relationships between classes. 1
1
PersonData
Test
1
1
includes member-variables and member-functions for identification of the tested person. Class TFormTest consists of( uses) class Figure, Answer, Timer and Instruction. Class Instruction includes functions for introducing the tested person to the test procedure. Class Figure includes variables and functions for initialization and drawing 5 figures. Class Answers saves time for answer and defines type of answer – true or false. Class Timer registers times for each answer and when previously defined time for test finishes it terminates the test.
1 24
1
Answers
Instruction
TFormMenu
Instruction
TFormTestRot Answer 1
Figure
Stimuli
5
1
Person Timer
Figure
Timer
Fig.4. Class diagram of developed test
uses inherits
Fig.6. Class diagram for Windows version of the test
After finishing the test results and personal data are saved in the file for future statistical data processing. Future developing of the test is connected with including a database for saving and retriving data for different assessment persons.
friend class
module
Fig.5. Notation for diagrams Figure 6 shows class diagram for Windows version of the test. Class Test is replaced with two classes TFormMenu and TFormTestRot. Class TFormMenu includes functions and objects for visualization main form of the test and for saving and printing the results from the test (fig 7). It uses class TFormTestRot that starts test procedure in separate form. Class TFormMenu uses class Person that
Fig.7. Main Form of the Windows Test
RotFig1
RotFig2
RotFig3
Fig.8. Modules in designed test REFERENCES Class diagrams describe the logical static design of the software test. Physical design of the software may be differ from the logical. Module diagrams describe the physical structure of the software test. Each module consists of separately compiled classes and functions in C++. The software test consists of three modules. Module RotFig1, RotFig2, RotFig3 ( fig.8). Module RotFig1 consists of classes TFormMenu and Person. These are classes, which consists of classes and member-functions for setting the parameters of the test, input personal data and saving the results and data. Module RotFig2 consists of classes TFormTestRot and Timer. Classes and functions in this module are responsible for organizing visualization of the stimuli, registering the answers and times. Module RotFig3 consists of classes Instruction, Answer, and Figure. These are classes, member functions and data for particular test. CONCLUSIONS A software test for testing the disorders of visual object recognition connected with transformation of visual mental images with original Bulgarian set of objects has been designed. The test has been tested and validated in Medical Academy – Sofia, clinic of Neurology. Object-oriented approach for developing the software has been applied.
Biederman, I.,(1994) Recognition by components: A theory of human image understanding. Psychological Review, pp.115-147. Booch, G, (1991), Object Oriented Design with Applications, Benjamin/Cummings Publishing Company Inc. Booch, G., Rumbaugh, J., and Jacobson I., ( 1999), The Unified Modeling Language, Adison-Wesley Reading, MA. HOOD Working Group (1989), HOOD Reference manual, Issue 3.0, European Space Agency, Noordwijk, Netherlands. Wasserman A.I., Pircher P.A. and Muller R.J. ( 1990). The object-oriented structured design notation for software design representation, IEEE Computer, March, 1990, 5062. M.Terzieva, B.Alexandrova, A.Petrov, I.Tournev, L.Mavlov, ( 1996), A Study on visio-perceptive and Imagery Abilities – II Assessment of Visual Ment al Image Generation and Transformation, Bulgarian Journal of Psychology, No 4 (in Bulgarian)
COMPUTERIZED ASSESSMENT OF THE ABILITY FOR TRANSFORMATION OF VISUAL MENTAL IMAGES
Anelia Popandreeva Bulgarian Academy of Sciences - ICSR
Abstract. Transformation of visual mental images according cognitive theories is a subprocess of view imagery. Software test for asseement of the ability for mental rotation includes 24 tasks. Each of them consists of 5 figures, one of wich is a mirror figure of other. The tested person has to discover the mirror figure. The software is designed in two versions for running on any IBM-compatible personal computer operating under MS-DOS or Windows. Object-oriented approach for development of the software has been applied. Classes and their relationships are described. . Copyright © 2004 IFAC Keywords: Diagnostic tests, Object- Oriented Programming.
INTRODUCTION Transformation of visual mental images according cognitive theories is a sub-process of view imagery. Mental rotation is a basic transformation. It is a part of many tests (Biederman, I., 1994). In the first test for assessment mental rotation stimuli are letters in normal and mirror position. The tested person has to rotate them mentally to upright position. In the following tests stimuli are changed with digits, symbols or forms. 1. ASSESSMENT OF THE MENTAL ROTATIONS OF FIGURES IN 2D SPACE Test procedure includes 24 sets of stimulus. Stimuli are digits, letters and figures. Each set consists of 4
figures and one mirror figure. They are rotated on different angle (Terzieva, M et al. 1996). For the assessment has been developed computerized test. Test begins with instruction for the tested person. It is followed by an example. After that 24 tasks are presented to the tested person in the same order. Each task consists of 5 figures and the tested person has to discover the mirror figure in this set (fig.1). The time for visualization of the stimuli can be defined before beginning the test procedure. The true answers are weighted with 1 and false answers are weighted with 0. The software test records each answer and time for them for each task. After that it calculates the number of answers for different tasks and its percent of all answers (fig.2).
2.1. Requirements for computer test Test consists of 24 sets of figures. Each set includes one figure rotated in four different angles and one mirror figure. Each of the figures is drown of sequence of seesaw lines and/or arcs. Each set is visualized and the time for answer is calculated. Answer has to be defined as true or false answer. Test has to have ability for limiting the time for test procedure. Before testing identification data for tested person have to be input and saved. Test has to begin with instruction and example. Report of the test has to include personal data, time for test, and number of true answers, type and time for each answer.
Fig.1. Mental rotations in 2D space Rotation Number Years:
Name
On figure 3 is shown diagram of basic elements of the computer test.
True answers - 12 -> 50 % Time for test -
0 min
1+ 2+ 3g 4+ 5g 6g 7+ 8+
17 g 18 + 19 g 20 + 21 g 22 + 23 g 24 +
3.03 sec 1.92 sec 1.04 sec 1.54 sec 0.77 sec 1.04 sec 0.82 sec 2.09 sec
9+ 10 g 11 g 12 g 13 + 14 + 15 g 16 +
0.93 sec 0.82 sec 0.82 sec 1.16 sec 1.43 sec 0.77 sec 0.99 sec 0.83 sec
26.26 sec 0.77 sec 0.93 sec 0.61 sec 0.77 sec 0.66 sec 0.60 sec 0.87 sec 1.05 sec
Person Data
Instruction
Figure
Answer
Timer
Report
Fig.2. Report of the test. 2. OBJECT -ORIENTED APPROACH FOR DEVELOPMENT OF THE SOFTWARE Object-orientation is a technique for development of software organized as a number of objects that interact. Among the most benefits of designing the software with object-oriented approach is understanding, moulding the problem domain more naturally, developing the software systems from reusable modules, using the programming languages, which are close to the solved problems and which allow efficient user-defined types, and information hiding (Booch, G, 1991). The most popular objectoriented design methods are Booch (Booch, G, 1991), OOSD ( Wasserman et al., 1990), and HOOD methods ( HOOD, 1989). Booch’s method is one of the best-worked-out design methods. It is not tied to programming language. It has very reach notation of structure. A convergence of object-oriented methods led to the unified modeling language ( UML) notation ( Booch et al., 1999). Computerized test for assessment of the ability for transformation of visual mental images has been designed with Booch’s method.
Fig.3. Basic elements of the test 2.2. Design Proceeding from the requirements it is possible to define key abstractions PersonData, Instruction, Timer, Figures( Stimuli), Answers. Logical structure of the system is presented with class and object diagrams. During development the software tool classes PersonData, Test, Figure, Answers, Instruction and Stimuli have been designed. Class Test organizes the test procedure. It consists of (uses) classes PersonData, Instruction, Stimuli and Answers. Class PersonData includes member-variables and member-functions for identification of the tested person. Class Test includes variables and functions for running the picture test, for saving and printing the results from the test. Class Instruction includes functions for introducing the tested person to the test procedure. Class Stimuli consists of( uses) class Figure. Class Figure includes variables and functions for initialization and drawing 5 figures. Class Answers saves time for answer and defines type of answer – true or false. Class Timer registers times for test and
for each answer. Classes Timer and Answers are connected through functions friends. Figure 4 shows class diagram for developed test. Figure 5 shows notation for the relationships between classes. 1
1
PersonData
Test
1
1
includes member-variables and member-functions for identification of the tested person. Class TFormTest consists of( uses) class Figure, Answer, Timer and Instruction. Class Instruction includes functions for introducing the tested person to the test procedure. Class Figure includes variables and functions for initialization and drawing 5 figures. Class Answers saves time for answer and defines type of answer – true or false. Class Timer registers times for each answer and when previously defined time for test finishes it terminates the test.
1 24
1
Answers
Instruction
TFormMenu
Instruction
TFormTestRot Answer 1
Figure
Stimuli
5
1
Person Timer
Figure
Timer
Fig.4. Class diagram of developed test
uses inherits
Fig.6. Class diagram for Windows version of the test
After finishing the test results and personal data are saved in the file for future statistical data processing. Future developing of the test is connected with including a database for saving and retriving data for different assessment persons.
friend class
module
Fig.5. Notation for diagrams Figure 6 shows class diagram for Windows version of the test. Class Test is replaced with two classes TFormMenu and TFormTestRot. Class TFormMenu includes functions and objects for visualization main form of the test and for saving and printing the results from the test (fig 7). It uses class TFormTestRot that starts test procedure in separate form. Class TFormMenu uses class Person that
Fig.7. Main Form of the Windows Test
RotFig1
RotFig2
RotFig3
Fig.8. Modules in designed test REFERENCES Class diagrams describe the logical static design of the software test. Physical design of the software may be differ from the logical. Module diagrams describe the physical structure of the software test. Each module consists of separately compiled classes and functions in C++. The software test consists of three modules. Module RotFig1, RotFig2, RotFig3 ( fig.8). Module RotFig1 consists of classes TFormMenu and Person. These are classes, which consists of classes and member-functions for setting the parameters of the test, input personal data and saving the results and data. Module RotFig2 consists of classes TFormTestRot and Timer. Classes and functions in this module are responsible for organizing visualization of the stimuli, registering the answers and times. Module RotFig3 consists of classes Instruction, Answer, and Figure. These are classes, member functions and data for particular test. CONCLUSIONS A software test for testing the disorders of visual object recognition connected with transformation of visual mental images with original Bulgarian set of objects has been designed. The test has been tested and validated in Medical Academy – Sofia, clinic of Neurology. Object-oriented approach for developing the software has been applied.
Biederman, I.,(1994) Recognition by components: A theory of human image understanding. Psychological Review, pp.115-147. Booch, G, (1991), Object Oriented Design with Applications, Benjamin/Cummings Publishing Company Inc. Booch, G., Rumbaugh, J., and Jacobson I., ( 1999), The Unified Modeling Language, Adison-Wesley Reading, MA. HOOD Working Group (1989), HOOD Reference manual, Issue 3.0, European Space Agency, Noordwijk, Netherlands. Wasserman A.I., Pircher P.A. and Muller R.J. ( 1990). The object-oriented structured design notation for software design representation, IEEE Computer, March, 1990, 5062. M.Terzieva, B.Alexandrova, A.Petrov, I.Tournev, L.Mavlov, ( 1996), A Study on visio-perceptive and Imagery Abilities – II Assessment of Visual Ment al Image Generation and Transformation, Bulgarian Journal of Psychology, No 4 (in Bulgarian)