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Computer mouse motion analysis in computerized screening tests for dementia: Interaction design and analysis
Abstracts: Clinical Assessment / 1 (Suppl 1) (2005) 80% of those with at least some college (Chi-square ⫽ 31.41). ROC curve analyses on the two educational levels revealed that cut-points lead to sensitivities/specificities of .93/.83 (⬍⫽12 yrs) and .77/.83 (13⫹ yrs). Areas under the curve were high (.917 for ⬍⫽ 12 yrs education and .888 for 13⫹ yrs). These findings indicate that the CANS-MCI is an effective screen for the need for full neuropsychological evaluations. However, a larger sample is needed to produce a more robust algorithm for individuals with low levels of education. Multiple screenings over time are recommended for highest predictive validity.
P-054
EEG Z-SCORE PATTERN MATCHING DIAGNOSIS OF AD
Toshimitsu Musha1, Naohiro Suzuki2, Takayoshi Kurachi1, Yukio Kosugi2; 1Brain Functions Lab., Inc., Kawasaki, Japan; 2Tokyo Institute of Technology, Yokohama, Japan Background: Scalp potential distribution of band-limited EEG ␣ component loses smoothness with progress of AD because of developing local impairment of synaptic-neuronal function, and at the same time its activity becomes unstable1). In place of the ␣ component which requires closed eye situation, we examined thecomponent in 13⬃30 Hz, and found that its fluctuation mode can sensitively discriminate or screen AD patients from normal subjects in the early stage. Objective(s): Prevention of dementia requires mass screening which covers a large number of candidates who may become dementia in the near future, and hence a required diagnosis should be inexpensive, non-invasive, sensitive, reliable and easy to operate. We aim at establishing such a diagnosis method as satisfying these requirements. Too large or too small a power fluctuation of thecomponent as compared to the normal one is a sign of abnormality in synapticneuronal activity, and a new diagnosis method for dementia has been developed using this nature. Methods: A scalp potential of the component xj(t) on channel j is recorded with 21 electrodes arranged according to the 10-20 system. Its normalized power variance (NPV) is defined as xj4 /xj22 - 1 where denotes averaging over 2 min. The averaged z-score maps of NPV over 25 very mild (MMSE⫽26⫾1.8) AD patients and 24 moderately severe (MMSE⫽15.3⫾6.4) AD patients, respectively, are made in reference to a group of 40 normal controls, and they are regarded as the standard template maps characterizing these two classes of AD. Then correlation coefficients C of a z-score map of an individual with the template z-score maps are regarded as a measure of likelihood to very mild and moderately severe AD, respectively. Conclusions: The cutoff values of sensitivity vs specificity characteristics to AD as functions of C have cut-off values of 0.67 and 0.75 at C ⫽ 0.2, respectively, for very mild and moderately severe AD. For C ⬎ 0.35 the false positive probability is 20% and for C ⬍ 0.08 the false negative probability is 20% in screening of very mild AD.1) T.Musha, et al., Clinical Neurophysiol, 113(2002)1052-1058.
P-055
COMPUTER MOUSE MOTION ANALYSIS IN COMPUTERIZED SCREENING TESTS FOR DEMENTIA: INTERACTION DESIGN AND ANALYSIS
Amos D. Korczyn1, Aharonson Vered2; 1Sackler School of Medicine, Tel-Aviv University, Tel Aviv, Israel; 2Afeka, Tel-Aviv Academic College of Engineering, Tel Aviv, Israel Background: In many neuropsychological tests the examinee has to point or draw on a paper template. When adapting such tests to the computer, the mouse, the cursor movements on the screen are use instead. Computer mouse usage, however, poses problems which are even more severe than keyboard usage, particularly on elderly, computer naive people. On the other hand, a wealth of data can be derived from analysis of the mouse
S25
movement. Objective: We studied methods for interaction design and analysis to enhance both usability and interpretation of computerized tests using mouse. Methods: We have adapted to computer a cognitive screening test (“strike out a symbol”) with the mouse as a user’s input device. The computer adaptation was designed in a usability lab scenario, with subjects’ comments and performance evaluation as guidelines for the design. The test consisted of 3 successive segments in which the interaction gradually become more complex. The test was administered to 76 subjects, over 50 years old (53 were computer naı¨ve). 35 of the subjects were referred to a memory clinic with complaints on memory impairment while the remainder 41 were age matched controls. Prior to the test, all subjects performed at least 4 computerized cognitive tests that involved keyboard presses, which lasted not more than 30 minutes. The complete session took 40 minutes or less for all subjects. The subjects’ performance was primarily analyzed by response correctness (striking out the correct symbols). Spatial motion analysis determined features related to the quality of cursor movement. Metrics were developed to evaluate speed, variance from expected trajectories and jerkiness. In addition mouse clicking patterns where quantified. Results: Only 22 out of 35 memory clinic subjects (compared to 39 out of the 41 controls) were able to complete the test. Different patterns were observed in the cursor movement metrics between skilled and computer naı¨ve subjects, and between the control and memory impaired group, in either computer skilled or computer naive groups. Conclusion: The results imply that computer mouse interaction may be valuable in screening subjects with memory impairment, but that the interface should be carefully designed to overcome usability problems.
P-056
THE ALZHEIMER’S DISEASE ASSESSMENT SCALE - COGNITIVE SUBSCALE (JAPANESE VERSION): THE PERFORMANCE IN COMMUNITY-DWELLING PEOPLE WITH MILD COGNITIVE IMPAIRMENT
Chiine Kodama1, Hiroko Noguchi2, Toru Kinoshita3, Shin Hidaka4, Megumi Sasaki4, Fumio Yamashita2, Takashi Asada4; 1National Center Hospital for Mental, Nervous and Muscular Disorders, Kodaira, Japan; 2 National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Japan; 3Kodama Clinic, Shinagawa, Japan; 4 University of Tsukuba, Tsukuba, Japan Background: The evaluation of cognitive status change in elderly with mild cognitive impairment (MCI) over years is important, because recent studies indicated that people with MCI have a high risk of progression to dementia or Alzheimer’s disease (AD). The AD Assessment Scale-Cognitive Subscale (ADAS-cog) is a useful cognitive test for assessing change in people with AD. In Japan, the Japanese version of the ADAS-cog (ADASJcog) is also used widely for AD assessment, but the performance on it in persons with MCI has not been reported. Objective(s): To compare the performance on ADAS-Jcog for MCI (ADAS-Jcog-MCI) in MCI persons with normal elderly and AD patients. ADAS-Jcog-MCI is an extended version of original ADAS-Jcog including two additional subtests (word list delayed recall and attention). Methods: 1708 community-dwelling individuals aged 65 and over, were evaluated by a neuropsychological battery and other clinical measures in the Tone Project, an epidemiologic survey on the prevalence of pre-dementia. As a part of survey, 373 subjects participated in a following intervention trial, and 94 subjects out of 373 were evaluated by ADAS-Jcog-MCI. On the score of the neuropsychological battery, 66 subjects were categorized into cognitively normal, and 9 subjects met operational criteria for amnestic MCI that memory domain showed an impairment of ⬎1.0SD and no difficulty in any other area of cognitive functioning compared with the age- and education-specific norms. 10 AD patients were recruited from two memory clinics and
P-054
EEG Z-SCORE PATTERN MATCHING DIAGNOSIS OF AD
Toshimitsu Musha1, Naohiro Suzuki2, Takayoshi Kurachi1, Yukio Kosugi2; 1Brain Functions Lab., Inc., Kawasaki, Japan; 2Tokyo Institute of Technology, Yokohama, Japan Background: Scalp potential distribution of band-limited EEG ␣ component loses smoothness with progress of AD because of developing local impairment of synaptic-neuronal function, and at the same time its activity becomes unstable1). In place of the ␣ component which requires closed eye situation, we examined thecomponent in 13⬃30 Hz, and found that its fluctuation mode can sensitively discriminate or screen AD patients from normal subjects in the early stage. Objective(s): Prevention of dementia requires mass screening which covers a large number of candidates who may become dementia in the near future, and hence a required diagnosis should be inexpensive, non-invasive, sensitive, reliable and easy to operate. We aim at establishing such a diagnosis method as satisfying these requirements. Too large or too small a power fluctuation of thecomponent as compared to the normal one is a sign of abnormality in synapticneuronal activity, and a new diagnosis method for dementia has been developed using this nature. Methods: A scalp potential of the component xj(t) on channel j is recorded with 21 electrodes arranged according to the 10-20 system. Its normalized power variance (NPV) is defined as xj4 /xj22 - 1 where denotes averaging over 2 min. The averaged z-score maps of NPV over 25 very mild (MMSE⫽26⫾1.8) AD patients and 24 moderately severe (MMSE⫽15.3⫾6.4) AD patients, respectively, are made in reference to a group of 40 normal controls, and they are regarded as the standard template maps characterizing these two classes of AD. Then correlation coefficients C of a z-score map of an individual with the template z-score maps are regarded as a measure of likelihood to very mild and moderately severe AD, respectively. Conclusions: The cutoff values of sensitivity vs specificity characteristics to AD as functions of C have cut-off values of 0.67 and 0.75 at C ⫽ 0.2, respectively, for very mild and moderately severe AD. For C ⬎ 0.35 the false positive probability is 20% and for C ⬍ 0.08 the false negative probability is 20% in screening of very mild AD.1) T.Musha, et al., Clinical Neurophysiol, 113(2002)1052-1058.
P-055
COMPUTER MOUSE MOTION ANALYSIS IN COMPUTERIZED SCREENING TESTS FOR DEMENTIA: INTERACTION DESIGN AND ANALYSIS
Amos D. Korczyn1, Aharonson Vered2; 1Sackler School of Medicine, Tel-Aviv University, Tel Aviv, Israel; 2Afeka, Tel-Aviv Academic College of Engineering, Tel Aviv, Israel Background: In many neuropsychological tests the examinee has to point or draw on a paper template. When adapting such tests to the computer, the mouse, the cursor movements on the screen are use instead. Computer mouse usage, however, poses problems which are even more severe than keyboard usage, particularly on elderly, computer naive people. On the other hand, a wealth of data can be derived from analysis of the mouse
S25
movement. Objective: We studied methods for interaction design and analysis to enhance both usability and interpretation of computerized tests using mouse. Methods: We have adapted to computer a cognitive screening test (“strike out a symbol”) with the mouse as a user’s input device. The computer adaptation was designed in a usability lab scenario, with subjects’ comments and performance evaluation as guidelines for the design. The test consisted of 3 successive segments in which the interaction gradually become more complex. The test was administered to 76 subjects, over 50 years old (53 were computer naı¨ve). 35 of the subjects were referred to a memory clinic with complaints on memory impairment while the remainder 41 were age matched controls. Prior to the test, all subjects performed at least 4 computerized cognitive tests that involved keyboard presses, which lasted not more than 30 minutes. The complete session took 40 minutes or less for all subjects. The subjects’ performance was primarily analyzed by response correctness (striking out the correct symbols). Spatial motion analysis determined features related to the quality of cursor movement. Metrics were developed to evaluate speed, variance from expected trajectories and jerkiness. In addition mouse clicking patterns where quantified. Results: Only 22 out of 35 memory clinic subjects (compared to 39 out of the 41 controls) were able to complete the test. Different patterns were observed in the cursor movement metrics between skilled and computer naı¨ve subjects, and between the control and memory impaired group, in either computer skilled or computer naive groups. Conclusion: The results imply that computer mouse interaction may be valuable in screening subjects with memory impairment, but that the interface should be carefully designed to overcome usability problems.
P-056
THE ALZHEIMER’S DISEASE ASSESSMENT SCALE - COGNITIVE SUBSCALE (JAPANESE VERSION): THE PERFORMANCE IN COMMUNITY-DWELLING PEOPLE WITH MILD COGNITIVE IMPAIRMENT
Chiine Kodama1, Hiroko Noguchi2, Toru Kinoshita3, Shin Hidaka4, Megumi Sasaki4, Fumio Yamashita2, Takashi Asada4; 1National Center Hospital for Mental, Nervous and Muscular Disorders, Kodaira, Japan; 2 National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Japan; 3Kodama Clinic, Shinagawa, Japan; 4 University of Tsukuba, Tsukuba, Japan Background: The evaluation of cognitive status change in elderly with mild cognitive impairment (MCI) over years is important, because recent studies indicated that people with MCI have a high risk of progression to dementia or Alzheimer’s disease (AD). The AD Assessment Scale-Cognitive Subscale (ADAS-cog) is a useful cognitive test for assessing change in people with AD. In Japan, the Japanese version of the ADAS-cog (ADASJcog) is also used widely for AD assessment, but the performance on it in persons with MCI has not been reported. Objective(s): To compare the performance on ADAS-Jcog for MCI (ADAS-Jcog-MCI) in MCI persons with normal elderly and AD patients. ADAS-Jcog-MCI is an extended version of original ADAS-Jcog including two additional subtests (word list delayed recall and attention). Methods: 1708 community-dwelling individuals aged 65 and over, were evaluated by a neuropsychological battery and other clinical measures in the Tone Project, an epidemiologic survey on the prevalence of pre-dementia. As a part of survey, 373 subjects participated in a following intervention trial, and 94 subjects out of 373 were evaluated by ADAS-Jcog-MCI. On the score of the neuropsychological battery, 66 subjects were categorized into cognitively normal, and 9 subjects met operational criteria for amnestic MCI that memory domain showed an impairment of ⬎1.0SD and no difficulty in any other area of cognitive functioning compared with the age- and education-specific norms. 10 AD patients were recruited from two memory clinics and