Characteristics of cursor trajectories controlled by the computer mouse

Cursor movements to targets labelled "stop": a kinematic analysis

The label 'Stop' potentially generates conflict-signifying important corrective action, or a warning not to touch. To examine potential conflict between an incongruent label (i.e. STOP) and an imperative command (i.e. MOVE!), 18 participants used a computer mouse to move a crosshair cursor to targets with superimposed labels. Trials systematically varied Imperative (blank or MOVE!), Label (+GO + or STOP) and movement Distance. Kinematic analyses examined response latency, movement duration and accuracy. Incongruent labels had little impact upon response latencies, but they affected cursor deceleration and the variability of cursor placement. Although reading is assumed to be obligatory, the impact of written labels is not immediate, instead affecting cursor deceleration. Indeed, responses to controls labelled STOP were less accurate than those labelled + GO+. As labelled interfaces can create error versus command confusions, enhancing the discriminability of controls to afford more obvious visible cues as to method of use is recommended. Practitioner summary: Emergency stop and shutdown controls can cause response conflict as their labels signify both urgent corrective actions and 'don't touch'. Response conflict caused by confusing superimposed labels is resolved as cursors near the target control and may result in reduced movement accuracy. Prior warnings may influence resolution of response conflict. Abbreviations: Hz: Hertz; M: Mean; ms: millisecond; mm: millimetre; S: second; SD: Standard Deviation; SE: Standard Error; USB: Universal Serial Bus.

Kinematic markers of skill in first-person shooter video games

Video games present a unique opportunity to study motor skill. First-person shooter (FPS) games have particular utility because they require visually guided hand movements that are similar to widely studied planar reaching tasks. However, there is a need to ensure the tasks are equivalent if FPS games are to yield their potential as a powerful scientific tool for investigating sensorimotor control. Specifically, research is needed to ensure that differences in visual feedback of a movement do not affect motor learning between the two contexts. In traditional tasks, a movement will translate a cursor across a static background, whereas FPS games use movements to pan and tilt the view of the environment. To this end, we designed an online experiment where participants used their mouse or trackpad to shoot targets in both visual contexts. Kinematic analysis showed player movements were nearly identical between contexts, with highly correlated spatial and temporal metrics. This similarity suggests a shared internal model based on comparing predicted and observed displacement vectors rather than primary sensory feedback. A second experiment, modeled on FPS-style aim-trainer games, found movements exhibited classic invariant features described within the sensorimotor literature. We found the spatial metrics tested were significant predictors of overall task performance. More broadly, these results show that FPS games offer a novel, engaging, and compelling environment to study sensorimotor skill, providing the same precise kinematic metrics as traditional planar reaching tasks.

Deconstructing the Functional Significance of the Error-related Negativity (ERN) and Midline Frontal Theta Oscillations Using Stepwise Time-locking and Single-trial Response Dynamics

Error-related electroencephalographic potentials have been used for decades to develop theoretical models of response monitoring processes, study altered cognitive functioning in clinical populations, and more recently, to improve the performance of brain-computer interfaces. However, the vast majority of this research relies on discrete behavioral responses that confound error detection, response cancellation, error correction, and post-error cognitive and affective processes. By contrast, the present study demonstrates a novel, complementary method for isolating the functional correlates of error-related electroencephalographic responses using single-trial kinematic analyses of cursor trajectories and a stepwise time-locking analysis. The results reveal that the latency of the ERN, Pe, and medial-frontal theta oscillations are all strongly positively correlated with the latency at which an initiated error response is canceled, as indicated by the peak deceleration of the initiated movement prior to a corrective response. Results are discussed with respect to current theoretical models of error-related brain potentials and potential relevance to clinical applications.

A Computer Mouse Using Blowing Sensors Intended for People with Disabilities

The computer is an important medium that allows people to connect to the internet. However, people with disabilities are unable to use a computer mouse and thus cannot enjoy internet benefits. Nowadays, there are various types of assistive technologies for controlling a computer mouse, but they all have some operational inconveniences. In this paper, we propose an innovative blowing-controlled mouse assistive tool to replace the conventional hand-controlled mouse. Its main contribution is that it uses microphones to induce small signals through the principle of airflow vibration, and it then converts the received signal into the corresponding pulse width. The co-design of software programming enables various mouse functions to be implemented by the identification of the blowing pulse width of multiple microphones. The proposed tool is evaluated experimentally, and the experimental results show that the average identification rate of the proposed mouse is over 85%. Additionally, compared with the other mouse assistive tools, the proposed mouse has the benefits of low cost and humanized operation. Therefore, the proposed blowing control method can not only improve the life quality of people with disabilities but also overcome the disadvantages of existing assistive tools.

Automatic Adjustment of Mouse Settings to Improve Pointing Performance

This article describes the development and evaluation of a software tool for the automatic configuration of mice and other pointing devices. The software is intended to accommodate the needs of people with physical impairments, with a goal of improved productivity and comfort during computer use. We successfully built prototype software that monitors user activity during performance of regular computer tasks and recommends appropriate Windows mouse settings to meet the user's specific needs. Twelve individuals with upper extremity impairments participated in an evaluation study. On average, the recommended settings significantly improved pointing performance for this subject group. The effect on trial time, entries, and error-free trials was significant at the 0.05 level. Trial time showed the strongest effect, improving by 29.3% with the settings recommended by our software. These results suggest that our software can successfully determine the appropriate mouse settings for an individual, yielding significant improvements in pointing performance.

Towards an automatic user profiling system for online information sites

Purpose

– The purpose of this paper is to identify demographic differences based on how users interact with web applications. The research is needed to develop future systems able to adapt the representation of online information to the user’s specific needs and preferences improving its usability. The following question guides this quest: is there a direct relationship between age and/or gender and interaction?

Design/methodology/approach

– GOMS (goals, operators, methods, and selection rules) analysis was used to reduce complex interaction tasks into basic operators like pointing, dragging, typing, etc. An experiment was designed to analyse the user performance in the use of these operators through five complex tasks: point-and-click, drag-and-drop, text selection, text edition and menu selection. The sample comprises 592 individuals which took part in the experiment. The performance was analysed using multivariate regression analysis. User laterality and the the user experience were used as control variables.

Findings

– The factors studied are significant enough to support user classification. The analysis evidenced that men performed significantly better than women when executing interaction pointing and dragging GOMS’s operators, but no significant differences arose with regard to the performance in the typing operators. Older users performed worse in all the interaction tasks. No significant performance differences were detected between left and right-handed users.

Research limitations/implications

– The study pretends to lay the ground for developing artificial intelligence-based classification systems (e.g. neural networks, decision trees, etc.) able to detect significant differences in user performance, classifying users according to their age, gender and laterality.

Practical implications

– This user profiling would drive the organisation, selection and representation of the online information according to the specific preferences and needs of each user. This would allow the design of new personalisation algorithms able to perform dynamic adaptation of user interfaces in order to improve the usability of online information systems.

Originality/value

– This work extends previous research on user performance under a new approach and improved accuracy. First, it relies on the combined and simultaneous analysis of ageing and gender and the use of user laterality and experience as control variables. Second, the use of the GOMS analysis allowed the design of tests that closely resemble the user interaction in online information systems. Third, the size of the sample used in this analysis is much bigger than those used in previous works, allowing a more thorough data analysis which includes the estimation of an advanced model which is quantile regression.

A cross-sectional study examining computer task completion by adolescents with cerebral palsy across the Manual Ability Classification System levels

AIM

The aim of this study was to analyze the cursor trajectories of adolescents with cerebral palsy (CP) when using a mouse for point-and-click computer tasks. By identifying some of the factors limiting cursor movement and gaining a better understanding of human movement, it will be possible to design more accessible computer interfaces.

METHOD

This study evaluated cursor trajectories of 29 individuals with bilateral CP who had different levels of upper limb function as measured by the Manual Ability Classification System, and compared the results with those of 12 adolescents with typical development.

RESULTS

Among adolescents with typical development, movement time increases linearly as the index of difficulty increases (Fitts' law); however, this linearity was not apparent in adolescents with bilateral CP.

INTERPRETATION

Interfaces for members of the population are designed around Fitts' law, with low precision requirements at indices of difficulty lower than 4. We found that interactive displays for adolescents with CP should be limited to an index of difficulty of 2.

Distinguishing Users By Pointing Performance in Laboratory and Real-World Tasks

Accurate pointing is an obstacle to computer access for individuals who experience motor impairments. One of the main barriers to assisting individuals with pointing problems is a lack of frequent and low-cost assessment of pointing ability. We are working to build technology to automatically assess pointing problems during every day (or real-world) computer use. To this end, we have gathered and studied real-world pointing use from individuals with motor impairments and older adults. We have used this data to develop novel techniques to analyze pointing performance. In this article, we present learned statistical models that distinguish between pointing actions from diverse populations using real-world pointing samples. We describe how our models could be used to support individuals with different abilities sharing a computer, or one individual who experiences temporary pointing problems. Our investigation contributes to a better understanding of real-world pointing. We hope that these techniques will be used to develop systems that can automatically adapt to users’ current needs in real-world computing environments.

A kinematic analysis of directional effects on mouse control

The directional effects associated with cursor movement controlled by a computer mouse have long been studied to improve mouse performance during precise tasks. However, those studies have rarely considered the kinematic variables associated with directional effects and have only analysed the projection of trajectories along the main axes of movement, eventually reducing the original dimensions of the data. In addition, as the angle of approach has a limited number of levels, it has been difficult to observe singular behaviour in the horizontal directions. In this study, we investigated the directional effects on kinematic variables when using a mouse to select circular targets. In this experiment, the measured trajectory of 16 different angles of approach was measured after separating the x and y components. The results revealed interesting biomechanical and cognitive features of mouse control and led to the suggestion of two improvements to be made upon the typical mouse design.

Effects of age and psychomotor ability on kinematics of mouse-mediated aiming movement

The objective of this research is to understand the influence of age and age-related psychomotor ability on the process of mouse-mediated aiming movement. It is premised on the notions that (1) mouse-mediated aiming movements can be better understood via studying its kinematics and (2) age is a surrogate variable in kinematic differences, and that age-influenced fundamental factors such as psychomotor ability may have a more direct effect. As expected, age kinematic differences were detected. However, when comparing with age, age-influenced psychomotor ability (i.e. manual dexterity) contributed more substantially to the variances of kinematics in the ballistic phase. For homing phase, in addition to manual dexterity, age-influenced wrist-finger speed was also a significant contributor. In future studies, it is suggested that components of visual processing should be included for better understanding of its role as an age-influenced fundamental ability in aiming movements. Applications of this research are discussed.

PRACTITIONER SUMMARY

This paper presents empirical data showing age effects in movement kinematics are chiefly mediated by age-related changes in psychomotor ability. Our findings provide additional data for existing and newer performance enhancement solutions, especially for those targeting older adults.

The effect of direction on cursor moving kinematics

There have been only few studies to substantiate the kinematic characteristics of cursor movement. In this study, a quantitative experimental research method was used to explore the effect of moving direction on the kinematics of cursor movement in 24 typical young persons using our previously developed computerized measuring program. The results of multiple one way repeated measures ANOVAs and post hoc LSD tests demonstrated that the moving direction had effects on average velocity, movement time, movement unit and peak velocity. Moving leftward showed better efficiency than moving rightward, upward and downward from the kinematic evidences such as velocity, movement unit and time. Moreover, the unique pattern of the power spectral density (PSD) of velocity (strategy for power application) explained why the smoothness was still maintained while moving leftward even under an unstable situation with larger momentum. Moreover, the information from this cursor moving study can guide us to relocate the toolbars and icons in the window interface, especially for individuals with physical disabilities whose performances are easily interrupted while controlling the cursor in specific directions.

Non-target flanker effects on movement in a virtual action centred reference frame

Visual selective attention is thought to underly inhibitory control during pointing movements. Accounts of inhibitory control during pointing movements make differential predictions about movement deviations towards or away from highly salient non-target flankers based on their potential cortical activation and subsequent inhibition: (1) Tipper et al. (Vis Cogn 4:1-38, 1997) "response vector model" predicts movements away from highly salient flankers; (2) Welsh and Elliott's (Q J Exp Psychol 57:1031-1057, 2004a and J Mot Behav 36:200-211, 2004b) "response activation model" predicts movements towards highly salient flankers early in the response, that is resolved by a race for inhibition. To eliminate the confounds of physical properties, such as obstacle avoidance and information cues of non-target objects, pointing was conducted in a virtual environment (graphical user interface). Participants were 14 skilled computer users who moved a computer cursor with a mouse to virtual targets. Analysis revealed non-target flankers significantly interfered with movement consistent with action centred selective attention, and reflecting a proximity-to-hand effect. Spatial analysis revealed evidence of highly salient flankers attracting movement, and less salient flankers repelling movement, supporting Welsh and Elliott's response activation model. These effects were achieved in a virtual 2D environment where interference caused by the physical properties of objects was less cogent.

The locus of adaptation to altered gain in aimed movements

Altered gain settings cause a mismatch between the actual movement amplitude across the surface and the distance covered on a real time visual display. The present study pursued three objectives of how adaptation to altered gain affects aimed motor behavior. First, we replicated findings of an earlier study reporting a negative linear relation between gain and both target acquisition time and end-point variability. This means that our data do not agree with the classic U-shaped relation between gain and acquisition time. Second, our results proved to be robust when we manipulated movement difficulty by varying target distance. And third, dividing a movement into four successive sections on the basis of key kinematic events revealed the locus of the adaptation to altered gain within movement execution. Time differences between gain conditions proved to start at a very early part of the movement, but appeared to be absent in the final movement section. In contrast, differences between gain conditions regarding the use of online feedback were also present in the last part of the movement during which the final target approach takes place.

Forward/up directional incompatibilities during cursor placement within graphical user interfaces

Within graphical user interfaces, an indirect relationship between display and control may lead to directional incompatibilities when a forward mouse movement codes upward cursor motions. However, this should not occur for left/right movements or direct cursor controllers (e.g. touch sensitive screens). In a four-choice reaction time task, 12 participants performed movements from a central start location to a target situated at one of four cardinal points (top, bottom, left, right). A 2 x 2 x 2 design varied directness of controller (moving cursor on computer screen or pen on graphics tablet), compatibility of orientation of cursor controller with screen (horizontal or vertical) and axis of desired cursor motion (left/right or up/down). Incompatibility between orientation of controller and motion of cursor did not affect response latencies, possibly because both forward and upward movements are away from the midline and go up the visual field. However, directional incompatibilities between display and controller led to slower movement with prolonged accelerative phases. Indirect relationships between display and control led to less efficient movements with prolonged decelerative phases and a tendency to undershoot movements along the bottom/top axis. More direct cursor control devices, such as touch sensitive screens, should enhance the efficiency of aspects of cursor trajectories.

A new approach to the mouse arm syndrome

OBJECTIVES

The study validates a new computer mouse concept. The tested device is a small mouse with a pivoting pen-shaped handle. The hypothesis behind the design is the assumptions that the pen grip requires less static tension than the normal mouse grip and that fine-motor, high precision tasks normally are done with finger movements with forearm at rest.

METHODS

Four muscles were monitored with electromyography (EMG) during work with a new mouse and with a traditional mouse.

RESULTS

EMG activity was significant lower, in M. pronator teres--46%, M. extensor digitorum--46%, M. trapezius--69%, and M. levator scapulae--82%, during work with the new mouse as compared to the traditional mouse.

CONCLUSION

Altering the design of the computer mouse can significantly reduce muscular tension.

Mouse movements of motion-impaired users: a submovement analysis

Understanding human movement is key to improving input devices and interaction techniques. This paper presents a study of mouse movements of motion-impaired users, with an aim to gaining a better understanding of impaired movement. The cursor trajectories of six motion-impaired users and three able-bodied users are studied according to their submovement structure. Several aspects of the movement are studied, including the frequency and duration of pauses between submovements, verification times, the number of submovements, the peak speed of submovements and the accuracy of submovements in two-dimensions. Results include findings that some motion-impaired users pause more often and for longer than able-bodied users, require up to five times more submovements to complete the same task, and exhibit a correlation between error and peak submovement speed that does not exist for able-bodied users.