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This article introduces the systemic-structural activity (SSA) approach to modeling user performance on human-computer interaction tasks. The human operator's eye and computer mouse movements were analyzed, and their interrelationship was investigated in the framework of the SSA theory. A new method of eye movement interpretation is presented. Procedures for development of predictive design models of human performance are also suggested. These design models can be developed based on either purely analytical procedures or a combination of analytical procedures and abbreviated experimental studies. Developed models are task specific and are described in terms of human actions and operations, rather than in terms of the internal cognitive architecture. The design process is considered in terms of stages of the sequential refinement of designed models.

Brain-computer interface (BCI) technology can provide nonmuscular communication and control to people who are severely paralyzed. BCIs can use noninvasive or invasive techniques for recording the brain signals that convey the user's commands. Although noninvasive BCIs are used for simple applications, it has frequently been assumed that only invasive BCIs, which use electrodes implanted in the brain, will be able to provide multidimensional sequential control of a robotic arm or a neuroprosthesis. The present study shows that a noninvasive BCI using scalp-recorded electroencephalographic (EEG) activity and an adaptive algorithm can provide people, including people with spinal cord injuries, with two-dimensional cursor movement and target selection. Multiple targets were presented around the periphery of a computer screen, with one designated as the correct target. The user's task was to use EEG to move a cursor from the center of the screen to the correct target and then to use an additional EEG feature to select the target. If the cursor reached an incorrect target, the user was instructed not to select it. Thus, this task emulated the key features of mouse operation. The results indicate that people with severe motor disabilities could use brain signals for sequential multidimensional movement and selection.

Two types of computer input devices, a conventional mouse and a roller bar one, were studied in terms of muscular activitiy in m. trapezius dexter, m. deltoideus anterior dexter and m. extensor digitorum dexter, and comfort rating. Fifteen university students and employees participated in this study. The order of the devices was random. While a task was performed, electromyography (EMG) data were recorded for each test. Muscular activity was found to be significantly lower for the roller bar mouse than for the conventional one. Comfort rating indicated there was a significant difference in moving a cursor with the conventional mouse compared to the roller bar one. It is concluded that a roller bar mouse allowed the subjects to work closer to the body compared to the conventional one, thus the former can be recommended as a general means of reducing upper extremity musculoskeletal disorders.

Two-button computer mouse users may exhibit sustained, static finger lifting behaviours to prevent inadvertent activations by avoiding finger pressure on the buttons, which leads to prolonged, static finger extensor muscle loading. One hundred graduate students were observed during normal computer work in a university computer facility to qualify and quantify the prevalence of lifted finger behaviours and extended finger postures, as well as wrist/forearm and grip behaviour, during specific mouse activities. The highest prevalences observed were 48% of the students lifted their middle finger during mouse drag activities, and 23% extended their middle finger while moving the mouse. In addition, 98% of the students rested their wrist and forearm (77%) or wrist only (21%) on the workstation surface, and 97% had an extended wrist posture (15 degrees -30 degrees ) when using the mouse. Potential applications of these findings include future computer input device designs to reduce finger lifting behaviour and exposures to risk factors of hand/forearm musculoskeletal pain.

We propose a method for fitting a piecewise parametric curve to a sequence of digitized points such as those acquired from a computer mouse or digitizing pen. The fitting is done on-the-fly rather than after a complete sequence of points has been acquired, thereby providing high-quality parameterized curves for immediate display during drawing. The method is fast, accurate, and robust, handles complex input paths, maintains corners, and ensures at least G 1 continuity at non-corner points. The method uses vector distance fields, which we describe here, to represent the intended input path of the digitized points in order to achieve its quality and performance. Detailed pseudocode is available online.

Research carried out in this technical paper suggests an application of the widely implemented eye tracking techniques. Traditionally, HCI uses mouse, keyboard as an input devices but this paper presents hand free interface between computer and human. Here providing a novel idea to control computer mouse cursor using human eyes movement. It controls mouse moving by automatically affecting the position where eyesight focused. The project mainly comprises of three sections namely Image Capture, Image Processing, and Cursor Control. After capturing image from webcam, the shape of pupil is recognized using Hough Transform and the center coordinate help to determine the exact point on the screen where the user is looking also coordinate will instruct the computer mouse to move specific location. This system is very helpful for solving the HMI problems of the disabled so that it can provide a way for them to communicate with the outside world.

BACKGROUND: A patient whose spinal cord was damaged due to accident may result in Tetraplegia or lose the ability to control his/her daily living environment. Currently, patients must use an invasive tool tongue movement, to help the patient communicate with the external environment. OBJECTIVE: This study designed a non-invasive tongue movement computer mouse system that allows the patient to use tongue movement to control a computer to communicate with the external environment. METHODS: Via a pressure sensor and assistive holder designed in this study, the pressure sensor can be moved using the assistive holder close to the mylohyoid muscle of the patient’s lower jaw. The changes in pressure from the mylohyoid muscle are converted into computer mouse control signals to control a computer to communicate with the external environment. RESULTS: This study is based on ISO9241-Part 9 to design four kinds of training modes with varying difficulties. The data were collected from five able persons participating in the test over 7 days. The data includes throughput, path efficiency, test completion time and reaction time. The data verifies that the proposed system is stable and practical for persons with disabilities. CONCLUSION: The non-invasive computer mouse system for sensing tongue movement can completely breakthrough the limitations of the invasive tongue movement sensing system. This study uses non-invasive, simple tongue movements that correspond to the stretching and shrinking of the lower jaw mylohyoid muscle to control the computer mouse.

To investigate a new alternative interaction method, called circling interface, for manipulating on-screen objects. To specify a target, the user makes a circling motion around the target. To specify a desired pointing command with the circling interface, each edge of the screen is used. The user selects a command before circling the target.To evaluate the circling interface, we conducted an experiment with 16 participants, comparing the performance on pointing tasks with different combinations of selection method (circling interface, physical mouse and dwelling interface) and input device (normal computer mouse, head pointer and joystick mouse emulator).A circling interface is compatible with many types of pointing devices, not requiring physical activation of mouse buttons, and is more efficient than dwell-clicking. Across all common pointing operations, the circling interface had a tendency to produce faster performance with a head-mounted mouse emulator than with a joystick mouse. The performance accuracy of the circling interface outperformed the dwelling interface.It was demonstrated that the circling interface has the potential as another alternative pointing method for selecting and manipulating objects in a graphical user interface. Implications for Rehabilitation A circling interface will improve clinical practice by providing an alternative pointing method that does not require physically activating mouse buttons and is more efficient than dwell-clicking. The Circling interface can also work with AAC devices.

Biometric identification systems build features, which describe people, using various data. Usually it is not known which of features could be chosen, and a dedicated process called a feature selection is applied to resolve this uncertainty. The relevant features, that are selected with this process, then describe the people in the system as well as possible. It is likely that the relevancy of selected features also mean that these features describe the important things in the measured behavior and that they partly reveal how the behavior works. This paper uses this idea and evaluates results of many runs of feature selection runs in a system, that identifies people using their moving a computer mouse. It has been found that the most frequently selected features repeat between runs, and that these features describe the similar things of the movements. © 2016 Author(s).

Stress is an unpleasant condition that entails negative emotions such as fear, worry and nervousness. Motivated by existing research that accompanies stress with physical reactions like increased heart rate, blood volume, pupil dilation and skin conductance, this work builds on the premise that measuring such reactions in real-time could implicitly identify stress of older adults at work while interacting with a system. For this purpose, an inhouse computer mouse was built with embedded sensors for measuring the users' heart rate, skin conductance, skin temperature, and grip force. We have developed a probabilistic classification algorithm that receives as input these physiological measurements, and accordingly identifies emotional stress events. This work contributes to a large body of research in user modeling, aiming to identify when computer users are stressed, and accordingly provide intelligent interventions and personalized solutions to help reduce their frustration and prevent negative health conditions. 1618 Sponsors: Conference code: 123010

Assisting older adults at work is of critical importance in nowadays fast-emerging computerized environments. Therefore, it is paramount to provide support to mitigate age-related cognitive degradation and to relieve their fear towards technological changes. In this demo paper, we present CogniWin, an integrated framework for providing personalized support to older adults at work, which aims to achieve the above goals and to make them feel more positive in prolonging their stay at work. We present an overall description of the system components and the integration architecture, and highlight the benefits of using the system. 1618 Sponsors: Conference code: 123010

The present study evaluated whether during a matching-to-sample procedure (MTS), the time spent observing stimuli is related to the establishment of selection or rejection controlling relationships in human participants. It also evaluated whether different response topographies (i.e., participants using the keyboard or mouse) would influence the duration of eye fixations. Ten college students participated. The procedure established conditional relationships among six sets of abstract stimuli. Five participants selected the comparison stimuli using a computer mouse and five used a keyboard. An eye-scan device recorded eye movements throughout the training procedure. After participants completed training, probes verified whether the conditional relationships learned were controlled by selection (e.g., if A1, select B1), by rejection (e.g., if A1, reject B2), or both. All participants displayed a similar pattern of stimuli observation. Time spent observing the sample stimulus (e.g., A1) was longer than observing the comparison stimuli (e.g., B1 and B2). Time spent observing S+ (positive stimuli; e.g., B1) was longer than observing S- (negative stimuli; e.g., B2). Duration of eye fixation was not related to selection or rejection controlling relationships, but different response topographies appeared to modulate the amount of time spent observing stimuli.

The procedures presented in this chapter generate points and lines. In an interactive computing environment, points may be introduced by (a) entering their coordinates, (b) clicking with the computer mouse cursor at a location on the computer monitor screen, (c) importing coordinates from an external file, and (d) constructing points by various geometric methods. Of these four means of creating points, the first three are considered to be highly sensitive to the computing environment at hand, and not subject to any geometric considerations. For this reason, they are to be excluded from this publication. Lines and curves, much like points, they too can be generated by fairly much the same means as points. Thus, the procedures to be presented in this chapter are those that pertain to the points and lines that can be created by various constructions with the aide of coordinate geometry. Curves are to be presented in subsequent chapters.

This study investigated the effects of a computer mouse that vibrates after 10 seconds of inactivity to remind the user to release their grip and rest their hand. A laboratory experiment tested the reactions of 11 female and 7 male participants to this vibrating mouse against a conventional mouse to see how it affected Ps performance of 5 tasks, their resting behavior and their mouse preference. No effects on task performance were found between the two conditions. The vibrating mouse induced significantly more resting behavior (p=0.02) and marginally more hand removals (p=0.06). However, it also induced significantly more unsupported hand hovering (p=0.00). Some Ps found that the vibrating mouse was disruptive to their performance. Further investigation of the effects of task type and user technique on the use of the vibrating mouse is needed.

It could be argued that the history of the computer mouse has already been written. It is true that a number of computer magazine articles and sections of books on computer history, along with online archives and Web encyclopedia entries, have described in some detail how the mouse we know today came into existence. However, these writings by and large have described the design, development, and production of the mouse without really assessing the extent to which it has affected our relationship with computing technology. The history of the mouse raises a number of interesting questions: Why did it take so long to become a mass-produced item? How did people react to the introduction of the mouse? What did the mouse represent, and what does it represent today? How and why did it become the single most accepted interface technology?...

This paper presents a novel haptic mouse that can be used as a human-computer interface and offers the capability of displaying properties such as patterns, gratings, and roughness. A small planar-distributed pin array is developed. Since the tactile display unit is small enough to be embedded into a computer mouse, we developed a texture display mouse. The performance of its texture display capability was verified. In addition, two psychophysical experiments have been conducted in order to ascertain the influence of vibrotactile stimuli. The first experiment showed that vibrational stimuli could be effective in the perception of patterns while from the second experiment, the functional relation between perceived roughness and component of vibrotactile stimuli was obtained. The experimental results have been applied to the development of a test-bed program.

Random dot cinematograms were used to probe motion perception in human observers ranging from 23 to 81 years of age. Stimuli were either broadband directional Noise, which produces no experience of global motion flow, or a narrower band directional Signal, which tended to produce experiences of coherent, global direction flow. On each trial, subjects rated their certainty that a Signal had been presented, and used a computer mouse to indicate the direction of perceived global flow. At all ages, sensitivity to motion and accuracy of perceived direction improved significantly as stimulus duration increased from 75 to 470 ms. However, older subjects (>70 years of age) were significantly less sensitive to motion, and were significantly less accurate at identifying the direction of movement. A control experiment, which found that older subjects accurately perceived and remembered the orientation of a line, ruled out the possibility that the observed deficits in motion perception were due to an inability on the part of older subjects to manipulate the computer mouse. Those control results also showed that both younger and older observers maintained robust visual representations over durations ranging from .24 to 6.0 s. The motion detection and identification results obtained from subjects less than 70 years of age were well fit by a simple multichannel model of motion, although different levels of additive internal noise were needed to fit detection data and direction-identification data, suggesting that motion direction and identification are constrained by different mechanisms. To fit the data from the oldest subjects, however, the values of model parameters had to be significantly altered, either by increasing the level of additive internal noise substantially, or by a smaller increase in noise coupled with an increase in the bandwidth of the model’s directionally selective channels. These results are qualitatively consistent with recent neurophysiological studies showing weaker directional selectivity and higher spontaneous noise in visual neurons of senescent monkeys and cats. � 2007 Elsevier Ltd. All rights reserved.

An individual's cardiovascular health is important. The measurement of blood pressure (BP) can be performed nonintrusively during normal daily activities. A study was designed to estimate systolic BP by measuring pulse arrival time (PAT) nonintrusively. PAT was obtained nonintrusively to estimate each individual's BP while he or she worked at a computer. Electrocardiogram (ECG) was measured with a capacitive-coupled electrocardiogram (CC-ECG) system and photoplethysmogram (PPG) was measured using specially installed circuits in a computer mouse. PAT was calculated from CC-ECG and PPG, and compared to PAT measured by the standard method. Three individuals participated in this study. Results correlated well. An equation to estimate BP from the measured PAT was derived for each of three individuals during a training period. Estimated BP was compared with measured BP in a series of experiments under varied BP conditions. For each individual, the estimated BP followed the measured BP within a tolerable error range. This method was also used for long-term BP monitoring. Results showed that this method could be useful for monitoring BP for telemedicine and e-health.

Antipredatory benefits are generally considered important in the evolution and maintenance of animal aggregations. One such benefit is the confusion effect: the reduced ease of prey capture experienced by some predators resulting from an inability to single out and attack an individual prey from a group as a result of cognitive or sensory limitations. Although widely cited, empirical data that do any more than demonstrate the effect are sparse. Here, we use the artificial system of humans attempting to "capture" images on a computer screen using a computer mouse to explore several hypotheses on the properties of the confusion effect. This system has the advantage that we can control the behavior of the prey and eliminate the risk of confounding factors due to differential prey behavior and/or phenotypes in groups of different sizes. One important result of our study is the demonstration that the confusion effect can occur in the absence of these confounding factors and indeed in the absence of complex coordinated behavior between individuals in the prey group (such as are commonly observed in schooling fish). We also demonstrate for the first time that an individual prey item can still benefit from the confusion effect if it is only loosely associated in space with a larger group of similar prey. Both these results suggest that the confusion effect can arise under less specialist circumstances than previously realized, and so the importance of this mechanism in shaping aggregation by prey and predator--prey interactions may be substantially greater than previously considered. Copyright 2007, Oxford University Press.

Because there is little empirical data available on how well young children are able to use a computer mouse, the present study examined their proficiency in clicking on small objects at various positions on the screen and their skill in moving objects over the screen, using drag-and-drop and click-move-click. The participants were 104 children from Kindergarten 2 and Grade 1. The results show that children in Kindergarten 2 clicked and moved slower than children in Grade 1. Nearly all of the children were able to click within 3 mm horizontally and 6 mm vertically from the centre of a 3 mm target. The findings also demonstrate that in educational software drag-and-drop is the most appropriate movement procedure as it was found to be faster than click-move-click and resulted in fewer interaction errors. Interesting differences between horizontal and vertical movements were found. It is concluded that young children are generally well capable of using a mouse to operate educational software, making this a suitable input device for such applications. © 2005 Elsevier Ltd. All rights reserved.

International audience; We present a simple method for measuring end-to-end latency in graphical user interfaces. The method works with most optical mice and allows accurate and real time latency measures up to 5 times per second. In addition, the technique allows easy insertion of probes at different places in the system I.e. mouse events listeners - to investigate the sources of latency. After presenting the measurement method and our methodology, we detail the measures we performed on different systems, toolkits and applications. Results show that latency is affected by the operating system and system load. Substantial differences are found between C++/GLUT and C++/Qt or Java/Swing implementations, as well as between web browsers.

The Waste Electrical and Electronic Equipment (WEEE) cause a major ecological problems. This paper shows how to reuse an optical mouse and CD reader into disuse in the implementation of a linear low-cost scanner to be used for educational purposes. The heart of the device, the ADNS2610 sensor of AVAGO, has ability to record images in grayscale. It is equipped with optical navigation technology for computer mouse applications among other possible uses. The mechanical part of a CD reader is also rescued to perform the linear movement of the scanner.

This paper delineates a vision based interface for regulating a computer mouse via 2D hand gestures. The evolution of Human Computer Interaction (HCI) has diverted the interest of researchers towards natural interaction techniques in recent years. Numerous applications of real time hand gesture based recognition in the real world have been deployed where we interact with computers. Hand gestures rely upon camera based color detection technique. This method mainly focuses on the use of a Web Camera to develop a virtual HCI device in a cost effective manner. This paper proposes a vision based system to control various mouse activities such as left and right clicking using hand gestures to make the interaction more efficient and reliable.

People unable to use hands to interact with computers do require special devices to gain access to information technology services. The rise of do-it-yourself (DIY) electronics makes it possible to release construction kits of a wide range of gadgets, including hands-free computer mice. In this paper we present one such building kit for a full-featured computer mouse that is controlled by head movements. The result kit includes an easy-to-find bill of materials, instructions to build the device and to use it. The first experiments showed that the mouse was working fine with people that have good control on head movements but that its embedded program must be customized for other individuals.

Computer work is characterized by sedentary static workload with low-intensity energy metabolism. The aim of our study was to evaluate the dynamics of skin surface temperature in the hand during prolonged computer mouse work under different ergonomic setups. Digital infrared imaging of the right forearm and wrist was performed during three hours of continuous computer work (measured at the start and every 15 minutes thereafter) in a laboratory with controlled ambient conditions. Four people participated in the study. Three different ergonomic computer mouse setups were tested on three different days (horizontal computer mouse without mouse pad, horizontal computer mouse with mouse pad and padded wrist support, vertical computer mouse without mouse pad). The study revealed a significantly strong negative correlation between the temperature of the dorsal surface of the wrist and time spent working with a computer mouse. Hand skin temperature decreased markedly after one hour of continuous computer mouse work. Vertical computer mouse work preserved more stable and higher temperatures of the wrist (&gt, 30 °C), while continuous use of a horizontal mouse for more than two hours caused an extremely low temperature (&lt, 28 °C) in distal parts of the hand. The preliminary observational findings indicate the significant effect of the duration and ergonomics of computer mouse work on the development of hand hypothermia.

V okviru diplomskega dela smo razvili razširitev aplikacije za prikaz žil s podporo za uporabo dveh dodatnih navigacijskih naprav (3D-miška Connexion Space navigator in brezdotična navigacijska naprava Leap Motion), ki sta predstavljali razširitev možnih vhodnih naprav poleg miške in tipkovnice za manipulacijo pogleda na 3D-model ožilja. Poleg same implementacije podpore za napravi v aplikacijo smo izpeljali uporabniško študijo, s katero smo ocenili primernost in enostavnost uporabe naprav v aplikaciji. Rezultate smo zbirali s podatki, ki so bili računalniško zajeti med interakcijo uporabnikov z napravami, ko so reševali različne manipulacijske naloge ter z reševanjem vprašalnikov SUS (System Usability Scale), ki predstavljajo enega izmed orodij, s katerim lahko ocenjujemo uporabniške vmesnike. Analiza rezultatov je potrdila, da je 3D-miška v takšnem okolju bolj uporabna ter tudi izpostavila nekatere pomanjkljivosti brezdotične navigacijske naprave Leap Motion. As part of the thesis we have developed applications for the extension of the vein display with support for two additional navigation devices (3D Connexion Space Navigator Mouse and hand gesture based navigation device Leap Motion) which represented an extension of possible input devices besides the keyboard and a mouse to manipulate the view of 3D model of neck veins. In addition to the implementation of support for the device in the application we carried out a user study in which we assessed the usability and ease of use of devices in the application. The results consisted from data we collected from the users' experience while they solved various manipulation tasks and the answers received from questionnaires SUS (System Usability Scale) which constitute one of the tools with which we can assess interfaces. Analysis of the results confirmed that the 3D mouse is more useful in such an environment and also highlighted some shortcomings of the hands free navigation device Leap Motion.

Computer mouse usage features could be used to distinguish web page visitors. Particular data instances representing user's navigation actions are insufficient when used separately to perform classification with basic k-nearest neighbors (kNN) classifier. We propose a modification of kNN method in which instances of the same class form groups. Finding the nearest neighbors is based on measuring distance between histograms representing distributions of values for the corresponding groups. The paper provides a series of experiments on dataset from 100 web visitors. It describes comparison of several distance metrics as well as different levels of grouping. Combination of non-parametric tests statistics for measuring distance and suitable size of groups improves classification success rate significantly.

When using virtual-reality paradigms to study animal behaviour, careful attention must be paid to how the animal's actions are detected. This is particularly relevant in closed-loop experiments where the animal interacts with a stimulus. Many different sensor types have been used to measure aspects of behaviour, and although some sensors may be more accurate than others, few studies have examined whether, and how, such differences affect an animal's behaviour in a closed-loop experiment. To investigate this issue, we conducted experiments with tethered honeybees walking on an air-supported trackball and fixating a visual object in closed-loop. Bees walked faster and along straighter paths when the motion of the trackball was measured in the classical fashion – using optical motion sensors repurposed from computer mice – than when measured more accurately using a computer vision algorithm called ‘FicTrac’. When computer mouse sensors are used to measure bees' behaviour, they modified their behaviour and achieved improved control of the stimulus. This behavioural change appears to be a response to a systematic error in the computer mouse sensor that reduces the sensitivity of this sensor system under certain conditions. Although the large perceived inertia and mass of the trackball relative to the honeybee is a limitation of tethered walking paradigms, observing differences depending on the sensor system used to measure bee behaviour was not expected. This study suggests that bees are capable of fine-tuning their motor control to improve the outcome of the task they are performing. Further, our findings show that caution is required when designing virtual-reality experiments, as animals can potentially respond to the artificial scenario in unexpected and unintended ways.

This paper presents a method for detecting patterns in the usage of a computer mouse that can give insights into user's cognitive processes. We conducted a study using a computer version of the Memory game (also known as the Concentration game) that allowed some participants to reveal the content of the tiles, expecting their low-level mouse interaction patterns to deviate from those of normal players with no access to this information. We then trained models to detect these differences using task-independent input device features. The models detected cheating with 98.73% accuracy for players who cheated or did not cheat consistently for entire rounds of the game, and with 89.18% accuracy for cases in which players enabled and then disabled cheating within rounds.

This paper presents a method for analyzing users' computer mouse interaction data with the aim to implicitly identify task completion difficulty while interacting with a system. Computer mouse motion streams and users' skin conductance signals, acquired via an in-house developed computer mouse, and users' feedback were investigated as reactions to task difficulty raising events. A classification algorithm was developed, producing real-time user models of user hesitation states. Preliminary results of a study in progress with seven older adults at work (age 56+) provide initial indications about links between mouse triggering states of user hesitation and task completion difficulty. Copyright is held by the author/owner(s). 18 1019 1024 Sponsors: ACM Special Interest Group on Computer-Human Interaction (ACM SIGCHI) Conference code: 116996 Cited By :4

Two-button computer mouse users may exhibit sustained lifted finger behaviors to prevent inadvertent activations by avoiding finger pressure on the buttons, leading to prolonged finger extensor muscle loading. One hundred graduate students were observed during normal computer work in a university computer facility to qualify and quantify the prevalence of lifted finger behaviors and extended finger postures, as well as wrist/forearm support, during specific mouse activities. The highest prevalences observed were 48% of the students lifted their middle finger during mouse drag activities, and 23% extended their middle finger while moving the mouse. In addition, 98% of the students rested their wrist and forearm (77%) or wrist only (21%) on the workstation surface. These findings indicate that two-button mouse users do lift and hold their fingers during computer work, while supporting their wrist/forearms. Potential applications include ergonomic design strategies to reduce exposure to risk factors that may contribute to hand/forearm musculoskeletal pain.

This study tested the notion that an equivalence relation may include a response when differential responses are paired with stimuli presented during training. Eight normal adults learned three kinds of computer mouse movements as differential response topographies (R1, R2, and R3). Next, in matching-to-sample training, one of the response topographies was used to select a comparison stimulus B (B1, B2, or B3) conditionally upon presentation of sample stimulus A (A1, A2, or A3), and to select stimulus D (D1, D2, or D3) conditionally upon presentation of stimulus C (C1, C2, or C3). After two sample–comparison–response relations (ABR and CDR) were established, 18 sample–comparison relations were tested (BA, DC, RA, RB, RC, RD, AC, CA, AD, DA, BC, CB, BD, DB, AA, BB, CC, and DD). In the RA, RB, RC, and RD tests, the differential responses (R1, R2, and R3) were used as sample stimuli. All subjects made class-consistent comparison selections in the tests. This study provides evidence that responses may become members of an equivalence class.

In spite of the rapid increase of computer use in our everyday life, not much effort is undertaken to take measures to prevent Musculoskeletal Disorders(MSDs). In this paper, we suggest a movable armrest which would lower the exposure to the MSDs, especially on the vicinity of arm. The aim of this study is to determine whether there are differences in wrist angle variations, forearm muscular loads, comfort and normal performance between the invented movable armrest and a conventional armrest when using a computer mouse. Eight experienced VDU workers performed a standardized simple task set which consists of 15 detailed tasks with each armrest. The wrist angle variations in the right arm were registered by electrogoniometer and the muscle activities in the shoulder, deltoid and two extensors in the forearm were also registered by electromyograph. The subjects rated perceived comfort while performing the tasks with each armrest. Working with the invented armrest, compared to general, gave significantly decreased wrist angle variations at most of the detailed tasks of both biaxial movements. Moreover, as the distance of targets increased, the difference of muscle activities in two different situations trend to be increasing. At the same time, in work with invented armrest, the subjects rated more comfort and they showed decreased normal performances in 8 detailed tasks which were mainly caused by macro moving time.

An earlier experiment demonstrated both possibilities and problems with reading a virtual map with a haptic mouse, the VTPlayerTM, the task being to locate states on a US map. The result was that addition of tactile matrix information had no effect on performance. The aim of the present experiment was to investigate the possibilities of improving the usefulness of the device by introducing two software modifications, one concerning texture within the states, another concerning temporal relations between tactile and auditory information when a state is entered. It was found that the former modification had a significant positive effect, but not the latter. The conclusion is that a haptic mouse may be a useful aid for non-visual reading of virtual maps, but that the software has to be optimized for touch. The general problem of how to use a computer mouse efficiently without visual feedback has also to be solved.

The wrist and thumb postures adopted during the use of three different types of computer mouse (mini mouse; standard mouse; MouseMan) to perform eight standardized tasks were evaluated. Thirty elementary students between seven to twelve years of age were studied using a magnetic tracking system. The peak value and angular range of motion of the wrist and thumb extension/flexion and radial/ulnar deviation were measured during performing 8 standard tasks. There were statistically significant larger values in the standard mice with regard to extreme wrist extension. Angular range of wrist extension observed for the standard mice were also much higher than the mini mouse and MouseMan. There were statistically significant larger values in the MouseMan with regard to extreme wrist ulnar deviation, and an average decrease in extreme thumb flexion and angular range of thumb flexion. The results from the questionnaire showed that most elementary students preferred to use the standard mouse (40%) next was the MouseMan (37%); and the last the mini mouse (23%). The recommendation of mouse types based on the hand length for elementary students was not statistically significant in our study.

Upper extremity musculoskeletal complaints and disorders are frequently reported among visual display units (VDU) workers. These complaints include cold forearms, hands or fingers. OBJECTIVE: The aim of this systematic review was to gain an insight into the relationship between objective and subjective temperature decrease and musculoskeletal disorders (MSDs) in the upper extremity in a VDU work environment by (internal or external) cooling of the arm and hand. Two questions were formulated: (1) Is a VDU work environment (temperature between 15 and 25 degrees C) associated with temperature decrease of the arm, hand or fingers in healthy subjects? (2) Is there a difference in arm, hand and finger temperature between patients with upper extremity MSDs and healthy subjects in a VDU work environment? METHODS: Through a systematic literature search in six databases between 1989 and October 2005, 327 articles were retrieved and 17 included. RESULTS: Forearm, hand and finger temperature significantly decreases when the ambient temperature (between 15 and 25 degrees C) decreases. The skin temperature in the hand that uses a computer mouse is lower than the other hand in the same ambient temperature. At baseline, no objective temperature differences are found between patient groups and controls, whereas in patients with cold hand complaints, lower skin temperatures are found compared to controls. The association between temperature (changes) in the forearm, hand or fingers during VDU work, and MSDs in the upper extremity is not clear. CONCLUSION: There is no consistent evidence available for the association between upper extremity MSDs and temperature changes in forearm, hand or fingers in an office work environment

A method called “SymbolDesign” is proposed that can be used to design user-centered interfaces for pen-based input devices. It can also extend the functionality of pointer input devices, such as the traditional computer mouse or the Camera Mouse, a camera-based computer interface. Users can create their own interfaces by choosing single-stroke movement patterns that are convenient to draw with the selected input device, and by mapping them to a desired set of commands. A pattern could be the trace of a moving finger detected with the Camera Mouse or a symbol drawn with an optical pen. The core of the SymbolDesign system is a dynamically created classifier, in the current implementation an artificial neural network. The architecture of the neural network automatically adjusts according to the complexity of the classification task. In experiments, subjects used the SymbolDesign method to design and test the interfaces they created, for example, to browse the web. The experiments demonstrated good recognition accuracy and responsiveness of the user interfaces. The method provided an easily-designed and easily-used computer input mechanism for people without physical limitations, and, with some modifications, has the potential to become a computer access tool for people with severe paralysis.

The purpose of this study was to evaluate the median nerve sonographically and estimate the prevalence of carpal tunnel syndrome (CTS) in computer mouse users. Forty-nine right wrists of 49 employees who had used a computer mouse were included in the study. Thirty-three right wrists of 33 non-mouse user employees were studied as a control group. Both the mouse user and non-mouse user employees underwent sonography and electromyography (EMG). Axial sonograms of the median nerve were obtained proximally, in the middle and distally in the carpal tunnel. At each level, flattening ratio and the cross-sectional area of the median nerve were calculated. We found no significant difference in any parameters between mouse users and control group ( p>0.05). However, when we compared mouse users according to the presence of pain, there was a significant increase in the cross-sectional area of the median nerve proximally in the mouse users having pain ( p2 and five (62.5%) had a distal flattening ratio over three. Prolonged use of a mouse may pose an occupational risk for employees. Sonography can serve as an initial step in symptomatic patients for diagnosis of CTS.

This study examined whether alternating between the preferred and non-preferred hands whilst using a computer mouse could be a viable injury prevention strategy within the workplace. Subjects ( n =30) were randomly assigned to either the control or experimental group, and participated in a 3 week training program involving 30 min of daily practice using only the preferred hand (control group) or both hands (experimental group). Control of the mouse by the non-preferred hand improved significantly (experimental group only) following training. The non-preferred hand for experimental group subjects also reached a level of proficiency equivalent to the preferred hand for work-related tasks. As a result, subjects felt more comfortable using their non-preferred hand for mouse work. The results suggest that with only minimal training, alternating between the preferred and non-preferred hands during work may not substantially reduce productivity. Relevance to Industry Occupational overuse syndrome is prevalent among workers who interact with computers for long sessions, especially when the mouse is the predominant input device. While seeking engineering control solutions to many of these workplace situations, ergonomists may also apply administrative controls to good effect. Sharing mouse activity between the preferred and non-preferred hands may, therefore, provide a viable injury prevention strategy to decrease the risk of unilateral mouse-related injuries.

Given the proliferation of touch-sensitive screen technologies, the factors contributing to efficiency of cursor control device were examined to better inform choice and design of Graphical User Interfaces. Fitts' law can be used to describe the relative efficiency of these cursor control devices. Experiment One required 18 participants to move a cursor between targets depicted upon a WACOM PL400 display graphics tablet, over various amplitudes, using a computer mouse or stylus, examining the speed and accuracy of cursor placement. The touch sensitive screen allowed faster acquisition of targets than the mouse. Since the mouse has a higher control/display ratio (gain) than the touch sensitive screen, Experiment Two addressed manipulation of the gain settings on computer mouse performance. Low gain offered some accuracy benefits. Possible posture problems associated with the touch sensitive screen were explored in Experiment Three. Screen orientation had little effect upon cursor positioning performance, suggesting the benefits of the touch sensitive screen can be transferred to user-friendly postures.

1. Human subjects were exposed to partial- and whole-body heating and cooling in a controlled environmental chamber to quantify physiological and subjective responses to thermal asymmetries and transients. 2. Skin temperatures, core temperature, thermal sensation, and comfort responses were collected for 19 local body parts and for the whole body. 3. Core temperature increased in response to skin cooling and decreased in response to skin heating. 4. Hand and finger temperatures fluctuated significantly when the body was near a neutral thermal state. 5. When using a computer mouse in a cool environment, the skin temperature of the hand using the mouse was observed to be 2–3 °C lower than the unencumbered hand.

Motories gestremde persone vind dit moeilik om ’n rekenaar te gebruik vanwee die feit dat hulle nie ’n muis kan beheer nie. In hierdie artikel word die ontwerp, implementering en evaluering van ’n oogknipbeheerde rekenaarmuis vir gebruik deur gestremde persone beskryf. Die deteksie van willekeurige oogknippe word deur middel van die weerkaatsing van infrarooi- (IR-) lig vanaf die vel langs die oog bewerkstellig, terwyl onwillekeurige knippe verwerp word. Dit stel motories gestremde persone, wat nie meer die gebruik van hul arms het nie, in staat om ’n rekenaar te bedryf. Al die funksies van ’n PS2-muis word geemuleer.

We tested the assumption that implicit attitude measures are related to automatic behavior, while explicit attitude measures are related to reflective behavioral intentions. In our study, attitudes towards persons with AIDS were assessed with both the Implicit Association Test (IAT) and an explicit attitude measure. Behavioral intentions were measured through a questionnaire. Automatic approach and avoidance predispositions were operationalized as the speed with which a computer mouse was either pulled towards (approach) or pushed away from the body (avoidance). Consistent with our expectations, the IAT was related to the automatic approach and avoidance behaviors, while the explicit attitude measure was related to behavioral intentions. These findings support the idea that automatic and reflective processes exert independent effects on behavior.

Many researchers have recommended the focus-window tracking (FWT) technique to study the course of information acquisition and visual attention. In FWT, the stimulus is blurred, and the subject scans for information by moving a clear window with a computer mouse. We show that poor calibration of the blur filter will bias search behavior in FWT because diagnostically useful information may leak through a filter even though the subjects are unaware of it. To provide a valid index of information acquisition, FWT requires an information filter that is calibrated to the task.

The objective of the present study was to gain insight into the effects of precision demands and mental pressure on the load of the upper extremity. Two computer mouse tasks were used: an aiming and a tracking task. Upper extremity loading was operationalized as the myo-electric activity of the wrist flexor and extensor and of the trapezius descendens muscles and the applied grip- and click-forces on the computer mouse. Performance measures, reflecting the accuracy in both tasks and the clicking rate in the aiming task, indicated that the levels of the independent variables resulted in distinguishable levels of accuracy and work pace. Precision demands had a small effect on upper extremity loading with a significant increase in the EMG-amplitudes (21%) of the wrist flexors during the aiming tasks. Precision had large effects on performance. Mental pressure had substantial effects on EMG-amplitudes with an increase of 22% in the trapezius when tracking and increases of 41% in the trapezius and 45% and 140% in the wrist extensors and flexors, respectively, when aiming. During aiming, grip- and click-forces increased by 51% and 40% respectively. Mental pressure had small effects on accuracy but large effects on tempo during aiming. Precision demands and mental pressure in aiming and tracking tasks with a computer mouse were found to coincide with increased muscle activity in some upper extremity muscles and increased force exertion on the computer mouse. Mental pressure caused significant effects on these parameters more often than precision demands. Precision and mental pressure were found to have effects on performance, with precision effects being significant for all performance measures studied and mental pressure effects for some of them. The results of this study suggest that precision demands and mental pressure increase upper extremity load, with mental pressure effects being larger than precision effects. The possible role of precision demands as an indirect mental stressor in working conditions is discussed.

Study objectives The objectives of this study were as follows: (1) to compare results of the discrete and the continuous methods for measuring breathlessness; (2) to examine test-retest reliability; (3) and to test the hypothesis that patients with COPD have higher slopes and lower x-intercepts and absolute thresholds for power production, oxygen consumption ( o 2 ), and minute ventilation as independent variables and breathlessness ratings as the dependent variable, as compared with healthy subjects. Design Visit 1 (familiarization) and visit 2 and visit 3 (2 days apart) with randomized assignment of the discrete and continuous methods for subjects rating breathlessness during cycle ergometry. Setting Cardiopulmonary exercise laboratory in a university medical center. Participants Twenty-four patients with COPD (mean age, 66 ± 8 years [± SD]) and 24 healthy subjects (mean age, 66 ± 10 years). Interventions None. Measurements and results Ratings of breathlessness on the Borg scale on cue with subjects moving and pressing the computer mouse button to indicate a rating (discrete method) or by moving the position of the mouse to adjust a vertical bar to indicate a change in breathlessness (continuous method). There were no significant differences in results between visit 2 and visit 3. Although peak exercise variables were similar with the discrete and continuous methods, both groups provided significantly more ratings of breathlessness with the continuous method. Patients with COPD exhibited higher slopes, lower x-intercepts, and lower absolute thresholds (breathlessness rating ≥ 0.5 [“just noticeable”] on the Borg scale) for power production and o 2 -breathlessness compared with healthy subjects (p Conclusions Elderly patients with COPD and healthy subjects are able to use the continuous method successfully. Reliability is excellent for both methods. The continuous method provides a greater number of breathlessness ratings over the course of exercise, and allows the clinician to calculate an absolute threshold and just-noticeable differences. Regression parameters and absolute thresholds discriminate between patients with COPD and healthy subjects.

With the spread of visual display terminals (VDT) in offices, the numbers of workers using VDT and the working hours at such equipment have increased rapidly in recent years. Also, preventive measures for fatigue have been proposed and the office-working environment has been improved. To examine the effects of the rapid changes in working conditions and environment on the health of VDT workers, we conducted a questionnaire survey in 2002. A self-reported questionnaire was distributed to 3,927 office workers; 2,374 (60.5%) responded. Subjects whose questionnaires had missing data were excluded from analysis. As a result, 1,406 (male: 1,069, female: 337) workers aged 20 to 59 were subjected to analysis. By a logistic regression model, we examined the association between VDT use and visual and musculoskeletal symptoms. Prevalence of eye strain and/or pain (72.1%) was the highest, followed by neck stiffness and/or pain (59.3%), low back stiffness and/or pain (30.0%) and hand or arm strain and/or pain (13.9%). Women consistently reported more discomfort than men. As a result of the logistic regression model, eye strain and/or pain was associated with dissatisfaction with airflow, but not with factors affecting visual symptoms as reported in previous studies, for example, reflection of light and blurred characters on the screen. It was thought that airflow appeared as a risk factor because the lighting environment had been improved in offices to prevent reflection of light on the screen. Neck stiffness and/or pain was associated with raising the shoulders during VDT work, the unsuitable shape of the computer mouse for a hand, and the inconvenient arrangement of the mouse in relation to the body. Hand or arm strain and/or pain were associated with the arrangement of the mouse and inappropriate height of the desk. Low back stiffness and/or pain were associated with dissatisfaction with the chair and using the keyboard without a wrist rest. Although measures to prevent fatigue had been implemented for VDT workers, risk factors for musculoskeletal symptoms would be the same as in previous studies.