The Effects of Screen Refresh Rate on Editing Operations Using a Computer Mouse Pointing Device

Two experiments are described in which subjects attempted to locate a specified target word in a short text using a cursor controlled by a computer mouse pointing device. The task was performed at screen refresh rates of 50 Hz, 75 Hz, and 100 Hz. In Experiment 1, both the timing and accuracy of the cursor movement was influenced by screen pulsation. During the early phase of the movement, performance was worse at 100 Hz, whereas in the later, visually guided phase, performance was worse at 50 Hz. In Experiment 2, eye movements were recorded as the task was performed. The results show that the cursor movement is typically preceded by an eye movement and that subjects do not directly inspect the cursor in the early stages of its movement. In the later phase of the movement the cursor is tracked for considerable periods of time. The data suggest that adverse effects of screen pulsation on the control of cursor movement are inherited from penalties incurred during the process of target computation but may also be influenced by concurrent eye movements.     

New methodology applied to bonnet macaques (Macaca radiata) to address some contradictory evidence on manual asymmetries in Old World monkeys

Seven bonnet macaques (Macaca radiata) with strong hand preferences in performing a computer-generated joystick task that required directing a cursor to contact a small stationary target on a monitor were given comparable experience with each hand on the task over a 5-week period. Hand use was randomly restricted to either only the left or only the right hand across trials by automatically inputting into a computer the unique identification numbers of microchips implanted in the forearms of each macaque. Subsequent presentation of a novel task requiring maintenance of contact between a cursor and a moving target revealed no performance difference between preferred and nonpreferred hands or between left and right hands on the basis of number of errors or time to complete the task. The findings suggest that the strong hand preference for these tasks does not derive from a performance advantage for the preferred hand.     

Performance of subgroups of left-handers and right-handers

Fifty-three left-handers with consistent left-hand preferences (CLH), 65 left-handers with inconsistent hand preferences (ILH), and 57 right-handers (RH) were given unimanual and bimanual performance tests involving skill, speed, and strength as well as tests of articulatory speed and verbal fluency. Contrary to claims in the current literature (Ponton, 1987), CLHs and ILHs do not differ in quality and speed of performance, but, in some tests, they do show asymmetries in opposite directions. Thus, when left-handers are treated as a combined group, the faulty impression of a lack of between-hand asymmetries arises. The results suggest that a distinction between CLHs and ILHs yields subgroups with reliably different and distinctive performance patterns which are not trivially attributable to differences in strength of lateralization. CLHs behave much like mirror image RHs, whereas ILHs show a dissociation between strength, fine manual skill, attentional asymmetries.     

光标显示模式对视线交互绩效与用户体验的影响研究

显示与反馈是人机交互的重要设计要素。对于视线交互这种自然人机交互技术,如何呈现视线光标,尚存在争论。本研究选取基于凝视点击范式的文本输入任务,设计了2（有无视点锁定功能）*2（有无实时注视点）被试内实验,探讨光标显示模式对视线交互绩效与用户体验的影响。结果：视点锁定功能可以提升交互绩效和用户体验,有无实时注视点对交互绩效无显著影响;输入速度的提升主要在于该功能能够让被试的视线更快地转移到下一个目标上。研究结果为视线光标的设计与应用提供了指导。     

Crossed-uncrossed difference (CUD) on reaction time and movement time in three two-choice experiments

The present study addresses the robustness and the reliability of the crossed-uncrossed difference (CUD) on a reaction time (RT) and a movement time (MT) component of a prescribed unimanual response to lateralized stimuli. Experiment 1 demonstrated positive CUDs both when a visual warning signal (WS) and an auditory reaction signal (RS) appeared on corresponding and non-corresponding sides of the body. Experiment 2 showed effect of handedness on CUD calculated among right-handers and left-handers. Experiment 3 investigated CUDs through five successive days, indicating that CUDs became steady and reliable although practice affected both RT and MT. All experiments indicated CUD on RT and MT. In addition, Experiments 1 and 2 demonstrated hemispheric asymmetries in favour of an anatomical theory while Experiment 3 did not show any asymmetries and supports an S-R compatibility theory.     

Effects of Fencing Training on Motor Performance and Asymmetry Vary With Handedness

Abstract

Previous studies showed that motor asymmetries are reduced in left-handers and after a long-term fencing training in right-handers. Interestingly, left-handed athletes are substantially over-represented in elite fencing. These findings have been speculatively explained by imbalance in experience of fighting opposite handedness opponents resulted from skewed distribution of handedness, i.e. lefties encounter more righties than righties encounter lefties. Whereas these assumptions could be accurate, the underlying mechanisms remain ambiguous. In this study, we investigated effects of fencing training on motor performance and asymmetry with respect to handedness. We compared fencing performance of left- and right-handed fencers in both training and combat conditions. In the combat condition, left-handers won seven out of twelve matches consisted of twelve bouts each. They also showed a significantly longer hit detection time, a measure indicating better quality of fencing attack. In the training condition, left-handed fencers completed fencing board tests significantly faster than right-handers. These findings provide additional factor of superior motor performance to be considered when interpreting over-representation of lefties in elite fencing. Furthermore, our left-handers were less lateralized, which could explain that superior motor performance. This idea is consistent with previous findings of reduced asymmetry in right-handed fencers when comparing to non-athletes.     

Pushing the limits of task difficulty for the right and left hands in manual aiming

The effects of task difficulty on the performance of the two hands in right-handers were examined in a manual-aiming paradigm. In order to examine both simple and complex tasks, movement amplitude, cursor size, and target size were manipulated, resulting in eight different indices of difficulty (as defined by Fitts' Law). Kinematic parameters examined included reaction time, movement time, time to and time after peak velocity, peak velocity, and resultant accuracy. Analysis revealed no differential effects of task difficulty on the overall movement times of the two hands. These results are discussed in light of current theories of manual asymmetries.     

Skill, strength, handedness, and fatigue

Thirty male subjects, 20 of whom were self-classified left-handers and 10 right-handers, were tested on a grip-strength task and a handwriting task with each hand, both under normal conditions and in a situation of induced experimental fatigue. On the basis of questionnaire scores, the left-handers were sub-divided into two groups comprising the 10 most left-handed and the 10 least left-handed subjects. The test of grip strength showed a small but significant deterioration in performance of both hands from fatigue. With the handwriting task, a similar significantly adverse effect of fatigue was recorded for all groups as well as a large significant difference in performance between the preferred and nonpreferred hands under normal conditions, which decreased under fatigue. An explanation of these differential effects is discussed in terms of the greater efficiency of the preferred hand in the highly developed skill of handwriting.     

自适应气泡光标——基于用户的点击增强技术

本研究选取了气泡光标这种典型的点击增强技术作为研究对象,从用户操作习惯和特点出发,提出基于频次算法的和基于时间算法的自适应气泡光标,并试图通过实验研究来探索这两款自适应气泡光标的影响作用。结果显示:(1)基于频次算法的和基于时间算法的自适应气泡光标在操作绩效和主观评价上均显著优于气泡光标;(2)两款自适应气泡光标在操作绩效和主观评价上无显著差异。本研究的结果为点击增强技术的设计优化提供了新的设计思路。     

Hemispheric asymmetries in attentional control: implications for hand preference in sensorimotor tasks

Liepmann (1908) proposed that handedness reflects the greater capacity of one hemisphere to learn the execution of skilled movements. Although asymmetries in motor control are an important basis for hand asymmetries, recent studies have suggested that handedness may be determined by multiple factors. In the present study, we examine how attentional asymmetries may contribute to hand preferences. Right-handed subjects participated in a reaction time task in which they were given preliminary information about where a target stimulus would occur (selective attention) or which hand to use for responding (selective intention). Our findings indicate that these processes influence each other reciprocally and favor a state of optimal attentional and intentional preparation of the right hand. We suggest that these hemispheric asymmetries in attentional control contribute to hand preferences in certain sensorimotor tasks.     

Relations among hand preference,craniofacial asymmetry,and ear advantage in young subjects

The relations for hand preference with craniofacial asymmetry and ear advantage, and between craniofacial asymmetry and ear advantage were investigated in young healthy subjects. Ear advantage was recorded as duration of hearing, craniofacial asymmetry by computerized tomography in 44 right-handed and 38 left-handed male and female high school students. Right-handers had a right ear advantage and a larger left craniofacial region, whereas left-handers had a left ear advantage and a larger right craniofacial region. These results are consistent with the speculation that hand preference may be related to craniofacial and consequently aural asymmetries.     

The Measurement of Handedness by Preference and Performance Tests

Hand preference and hand proficiency were compared on 50 male subjects (30 self-classified left-handers and 20 self-classified right-handers) according to their responses to a 20 item questionnaire and their performances on a handwriting and a grip-strength task. Performance differences between the two sides for each group were not related to overall preference assessments but were positively associated with hand preferences on corresponding questionnaire items. Distributions of the performance differences between the two sides for the right- and left-handers were well separated for handwriting but completely overlapped for grip strength. Significant correlations between the performances on each side were recorded on both tasks. The results stress the importance of using the same criteria in making preference vs. performance comparisons and highlight the need to recognize and control the influence of previous training or experience.     

Accessing the asymmetrical representations of causal relations and hierarchical relations in semantic memory

In a speeded aiming task, participants were trained to move a cursor with a mouse from a start position to target locations when the mouse–cursor relationships were either normal or reversed (vertically, horizontally, or both vertically and horizontally). Testing, which occurred after a 5-min delay, involved either the same or a different reversal condition. Response times improved across training, but no transfer occurred when reversal conditions were changed between training and testing. Specificity of training effects extended even to performance with the highly familiar normal mouse. Normal mouse use was slowed by a factor of two to three with training on a reversed mouse although the effect was transient in that case. To contend with a reversed mouse, participants apparently adopt a global inhibition strategy, suppressing all normal movements (and replacing them with sensorimotor remapped movements) but disinhibiting movements along any nonreversed dimension (selectively disengaging the sensorimotor remapping).     

Asymmetries in processing horizontal and vertical dimensions

The aim of this study was to determine whether the referential term on the horizontal dimension corresponds to the dominant hand and whether the referential term on the vertical dimension is independent of handedness. In order to verify the hypothesis, right-handers, left-handers, and ambidextrous subjects were required to verify and falsify statements including the words ABOVE and BELOW and the words LEFT and RIGHT. The results showed that right-handers were faster in verifying and falsifying the statements containing the term RIGHT, whereas left handers were faster in verifying and falsifying those containing the term LEFT. Ambidextrous subjects, however, showed no sign of asymmetry in the positional judgments of stimuli along the horizontal dimension. By contrast, right-handers, left-handers, and ambidextrous subjects were equally faster in verifying and falsifying the statements containing the term ABOVE than the statements containing the term BELOW. The relation between the positive term on the horizontal dimension and the dominant hand can be explained by the fact that, in the absence of any asymmetries in the physical world, the dominant hand can furnish a natural reference direction for judgments related to this dimension.     

利手与内隐左右空间情感效价关系的眼动研究

为探明手动作流畅性和情感材料呈现空间在不同利手者左右空间情感偏好中的关系,本研究将情绪Stroop范式和眼动测量相结合,通过反应速度和眼动数据将动作流畅性和空间情感注意偏向相分离,并考察其交互作用。结果发现右利手个体的反应速度存在优势手效应,不同利手者在使用左手时表现出对优势手同侧空间的内隐情感偏好,表明右利手个体的反应速度存在优势手流畅性的主导作用,手动作流畅性和内隐空间情感偏好的作用可以分离。     

MRI Asymmetries of Broca''s Area: The Pars Triangularis and Pars Opercularis

Broca's area, which includes the pars triangularis (PTR) and pars opercularis (POP), is a neuroanatomic region important in speech-language production. Previous data demonstrated that PTR asymmetries are highly correlated with language dominance determined by selective hemispheric anesthesia or Wada testing, suggesting that asymmetries of the PTR may, in part, predict language dominance. The POP, however, has not been measured on volumetric magnetic resonance imaging (MRI), and therefore, it is unclear whether morphological asymmetries of the POP exist, and whether these asymmetries differ in right- and left-handers. The purpose of this study was to determine if measurable asymmetries of the POP exist on MRI, and whether the direction of the asymmetries differ in right- and left-handers. The PTR and POP were measured on volumetric MRI scans of 16 right-handers and 16 left-handers matched for age and gender. There was a significant leftward asymmetry of the PTR in right- and left-handers, although the asymmetry was reduced in the left-handers. In contrast, there was a leftward asymmetry of the POP in right-handers, and a rightward asymmetry in the left-handers. Handedness, derived from a handedness inventory, was positively correlated with POP asymmetry.     

Asymmetries in the regulation of visually guided aiming

An experiment was conducted to examine the contribution of sensory information to asymmetries in manual aiming. Movements were performed in four vision conditions. In the full-vision condition (FV), subjects were afforded vision of both the hand and the target throughout the course of the movement. In the ambient-illumination-off condition (AO), the room lights were extinguished at movement initiation, preventing vision of the moving limb. In the target-off (TO) condition, the target was extinguished upon initiation of the movement. In a no-vision (NV) condition, ambient illumination was removed and the target was extinguished upon initiation of the response movement. Results indicated that accuracy was superior in the full-vision and target-off conditions and when movements were made by the right hand. Movements made by the right hand were also of shorter mean duration. The magnitudes of performance asymmetries were uninfluenced by vision condition. Analyses of movement kinematics revealed that movements made in conditions in which there was vision of the limb exhibited a greater number of discrete modifications of the movement trajectory. On an individual-trial basis, no relationship existed between accuracy and the occurrence of discrete modifications. These data suggest that although vision greatly enhances accuracy, discrete modifications subserved by vision reflect the imposition of nonfunctional zero-order control processes upon continuous higher-order control regimes.     

Asymmetries in the Regulation of Visually Guided Aiming

An experiment was conducted to examine the contribution of sensory information to asymmetries in manual aiming. Movements were performed in four vision conditions. In the full-vision condition (FV), subjects were afforded vision of both the hand and the target throughout the course of the movement. In the ambient-illumination-off condition (AO), the room lights were extinguished at movement initiation, preventing vision of the moving limb. In the target-off (TO) condition, the target was extinguished upon initiation of the movement. In a no-vision (NV) condition, ambient illumination was removed and the target was extinguished upon initiation of the response movement. Results indicated that accuracy was superior in the full-vision and target-off conditions and when movements were made by the right hand. Movements made by the right hand were also of shorter mean duration. The magnitudes of performance asymmetries were uninfluenced by vision condition. Analyses of movement kinematics revealed that movements made in conditions in which there was vision of the limb exhibited a greater number of discrete modifications of the movement trajectory. On an individual-trial basis, no relationship existed between accuracy and the occurrence of discrete modifications. These data suggest that although vision greatly enhances accuracy, discrete modifications subserved by vision reflect the imposition of nonfunctional zero-order control processes upon continuous higher-order control regimes.     

Colour correspondence effects between controlled objects and targets

It is increasingly popular to use movement trajectories as a measure of mental processes related to task performance. Often this is accomplished by moving a cursor to a target on a computer screen. However, the relation between features of the cursor and the targets is rarely, if at all, considered. In five experiments, we examined whether moving a cursor to a target was affected by the relation between their colours, even when this relation was task irrelevant. In Experiments 1–3, a mouse-controlled cursor was moved to one of two coloured targets. Results showed colour correspondence effects in latency to initiate a response, duration of movement times, and movement trajectories when the relationship between cursor and target colours was task relevant (Experiment 1) and when only the cursor colour was task relevant (Experiment 2), but not when only the target was task relevant (Experiment 3). Follow-up experiments using single targets showed that colour correspondence effects occurred as long as attention was dedicated to the colour of the cursor, even when neither the cursor nor the target colour was relevant to selecting the correct movement (Experiments 4 and 5). Furthermore, when the relation between cursor and target colours is task irrelevant, colour correspondence effects for response initiation times are uncorrelated with those for movement times and movement trajectories. We interpret the observed correspondence effect in terms of response coding, although attention cueing may also play a role, and suggest that greater consideration of cursor features is needed when examining movement trajectories in choice reaction tasks.