scholarly journals Uncertainty in aiming movements and its association to hand function

2015 ◽  
Vol 21 (3) ◽  
pp. 222-229 ◽  
Author(s):  
Flávia Priscila de Paiva Silva ◽  
Sandra Maria Sbeghen Ferreira de Freitas ◽  
Emelli da Silva Comenalle ◽  
Sandra Regina Alouche
Keyword(s):  
Reaction Time ◽  
Target Location ◽  
Hand Function ◽  
Reaction Times ◽  
Manual Dexterity ◽  
Movement Direction ◽  
Pinch Strength ◽  
Aiming Movements ◽  
Manual Tasks ◽  
The Right

AbstractThe purpose of this study was to analyze the influence of the uncertainty of target location on the planning and execution of aiming movements performed towards the ipsilateral and contralateral directions by the right and left upper limbs. In addition, the association between the performance of aiming movements and the performance of functional manual tasks was investigated. Two tasks were proposed: with prior knowledge of the movement direction (simple reaction time) or not (choice reaction time). The grip strength and manual dexterity were measured. The choice option in response (i.e. uncertainty) influenced planning of the aiming movements, but not its execution, while movements performed towards the contralateral direction were worse in execution as compared to the ipsilateral direction. Manual dexterity was significantly correlated with reaction times, while the performance during movement execution was significantly correlated with handgrip/pinch strength.

scholarly journals Lateralization of attention in adults with ADHD: Evidence of pseudoneglect

2020 ◽  
Vol 63 (1) ◽  
Author(s):  
Bartosz Helfer ◽  
Stefanos Maltezos ◽  
Elizabeth Liddle ◽  
Jonna Kuntsi ◽  
Philip Asherson
Keyword(s):  
Reaction Time ◽  
Visual Field ◽  
Reaction Times ◽  
Study Participant ◽  
Reaction Time Task ◽  
Right Visual Field ◽  
Time Variability ◽  
Incentive Condition ◽  
Reaction Time Variability ◽  
The Right

Abstract Background. We investigated whether adults with attention-deficit/hyperactivity disorder (ADHD) show pseudoneglect—preferential allocation of attention to the left visual field (LVF) and a resulting slowing of mean reaction times (MRTs) in the right visual field (RVF), characteristic of neurotypical (NT) individuals —and whether lateralization of attention is modulated by presentation speed and incentives. Method. Fast Task, a four-choice reaction-time task where stimuli were presented in LVF or RVF, was used to investigate differences in MRT and reaction time variability (RTV) in adults with ADHD (n = 43) and NT adults (n = 46) between a slow/no-incentive and fast/incentive condition. In the lateralization analyses, pseudoneglect was assessed based on MRT, which was calculated separately for the LVF and RVF for each condition and each study participant. Results. Adults with ADHD had overall slower MRT and increased RTV relative to NT. MRT and RTV improved under the fast/incentive condition. Both groups showed RVF-slowing with no between-group or between-conditions differences in RVF-slowing. Conclusion. Adults with ADHD exhibited pseudoneglect, a NT pattern of lateralization of attention, which was not attenuated by presentation speed and incentives.

scholarly journals Independent and interactive effects of thermal stress and mental fatigue on manual dexterity

2020 ◽  
Vol 319 (6) ◽  
pp. R703-R711
Author(s):  
Alessandro Valenza ◽  
Harry Charlier ◽  
Antonino Bianco ◽  
Davide Filingeri
Keyword(s):  
Thermal Stress ◽  
Reaction Time ◽  
Interactive Effect ◽  
Thermal Conditions ◽  
Mental Fatigue ◽  
Manual Dexterity ◽  
Interactive Effects ◽  
Manual Task ◽  
Air Temperatures ◽  
Manual Tasks

Many occupations and sports require high levels of manual dexterity under thermal stress and mental fatigue. Yet, multistressor studies remain scarce. We quantified the interactive effects of thermal stress and mental fatigue on manual dexterity. Seven males (21.1 ± 1.3 yr) underwent six separate 60-min trials characterized by a combination of three air temperatures (hot, 37°C; neutral, 21°C; cold, 7°C) and two mental fatigue states (MF, mental fatigue induced by a 35-min cognitive battery; no-MF, no mental fatigue). Participants performed complex (O’Connor test) and simple (hand-tool test) manual tasks pre- and posttrial to determine stressor-induced performance changes. We monitored participants’ rectal temperature and hand skin temperature (Thand) continuously and assessed the reaction time (hand-click test) and subjective mental fatigue (5-point scale). Thermal stress ( P < 0.0001), but not mental fatigue ( P = 0.290), modulated Thand (heat, +3.3°C [95% CI: +0.2, +6.5]; cold, −7.5°C [−10.7, −4.4]). Mental fatigue ( P = 0.021), but not thermal stress ( P = 0.646), slowed the reaction time (∼10%) and increased subjective fatigue. Thermal stress and mental fatigue had an interactive effect on the complex manual task ( P = 0.040), with cold-no-MF decreasing the performance by −22% [−39, −5], whereas neutral-MF, cold-MF, and heat-MF by −36% [−53, −19], −34% [−52, −17], and −36% [−53, −19], respectively. Only mental fatigue decreased the performance in the simple manual task (−30% [−43, −16] across all thermal conditions; P = 0.002). Cold stress-induced impairments in complex manipulation increase with mental fatigue; yet combined stressors’ effects are no greater than those of mental fatigue alone, which also impairs simple manipulation. Mental fatigue poses a greater challenge to manual dexterity than thermal stress.

Effect of Visual Complexity in Identification of Tachistoscopic Images

1994 ◽  
Vol 78 (3) ◽  
pp. 971-978 ◽  
Author(s):  
Robert Geheb ◽  
Keith E. Whitfield ◽  
Linda Brannon
Keyword(s):  
Reaction Time ◽  
Left Hemisphere ◽  
Right Hemisphere ◽  
Visual Complexity ◽  
Reaction Times ◽  
Right Cerebral Hemisphere ◽  
The Mean ◽  
The Times ◽  
The Right ◽  
Mean Reaction Time

The present study of gender differences in hemispheric processing involved identification of tachistoscopically presented images of varying complexity. A computerized tachistoscopic program was administered to 24 men and 34 women. Time to identify contour and detailed pictures presented to the left or right cerebral hemisphere was recorded. Mean reaction time for contour pictures was significantly faster than for detailed pictures, and mean reaction time to the right hemisphere was significantly faster than that to the left hemisphere. The mean reaction time for men to identify pictures exposed to the left hemisphere was significantly slower than that for exposure to the right hemisphere for women. The mean reaction time for both men and women to identify contour pictures exposed to the right hemisphere was significantly faster than the mean time to identify detailed pictures presented to the left hemisphere. The interaction of gender, hemisphere, and complexity was also significant in that mean reaction times for men to identify detailed pictures presented to the left hemisphere were slower than the times for women to identify contour pictures presented to the right hemisphere. The results are discussed in relation to theories about hemispheres, gender, and differences in picture features.

Temperament and attentional focus: Reaction time indicators of bias and cue salience

2009 ◽  
Vol 37 (3) ◽  
pp. 289-297
Author(s):  
Elizabeth R. Spievak ◽  
Anne M. Murtagh
Keyword(s):  
Reaction Time ◽  
Trait Anxiety ◽  
Target Location ◽  
Response Times ◽  
Reaction Times ◽  
Self Esteem ◽  
Attentional Focus ◽  
Personality Variables ◽  
Cue Salience ◽  
Trial Participants

This study was designed to test and extend prior work that linked personality variables, incentive cues and target detection reaction times. Participants completed a task in which they believed they might gain or lose points, depending upon the target location and their reaction time. After each trial, participants received a randomly generated positive or negative "feedback" message. Those higher in neuroticism showed shorter reaction times on trials following positive feedback. Participants higher in neuroticism and trait anxiety and those with lower scores for self-esteem and venturesomeness were more attentive to point-loss cues. Response times were longer for those who scored higher in trait anxiety and lower in self-esteem. Implications for understanding individual differences in attention and feedback response are discussed.

scholarly journals Effects of target location and uncertainty on reaching movements in standing position

2012 ◽  
Vol 26 (3) ◽  
pp. 485-493 ◽  
Author(s):  
Luiz de França Bahia Loureiro Junior ◽  
Sandra Maria Sbeghen Ferreira de Freitas ◽  
Paulo Barbosa de Freitas
Keyword(s):  
Reaction Time ◽  
Target Location ◽  
Movement Time ◽  
Target Position ◽  
Standing Position ◽  
Reaching Movements ◽  
Radial Error ◽  
Arm Reaching ◽  
The Right

The effects of target location and uncertainty of target position on reaching movements while standing were investigated. Ten healthy, right-handed adults stood facing a 17'' touchscreen. They were instructed to press with their right index fingertip a push bottom and touch the center of the target displayed on the screen after it was lighted on, moving quickly their arm. The target was shown either ipsi- or contralateral to the right arm and either in a certain or uncertain position. Reaction time (RT), movement time (MT), and radial error (RE) were assessed. Results revealed shorter RT (≈ 35 ms) and smaller RE (≈ 0.19 cm) for certain than for uncertain condition and slightly longer RT (≈ 8 ms) and MT (≈ 18 ms) for reaches towards the contralateral target. In conclusion, the findings of this study showing the effect of uncertainty of target location as well as target position are also applied to arm reaching in standing position.

scholarly journals Effect of Handedness and Footedness on Some Motoric Characteristics in Amateur Soccer Players

2019 ◽  
Vol 7 (12) ◽  
pp. 13
Author(s):  
Deniz Özge Yüceloğlu Keskin ◽  
Osman İmamoğlu ◽  
Menderes Kabadayı
Keyword(s):  
Reaction Time ◽  
Reaction Times ◽  
Hand Preference ◽  
Individual Characteristics ◽  
Soccer Players ◽  
Time Asymmetry ◽  
Left Hand ◽  
Significant Difference ◽  
The Right ◽  
Hands And Feet

The present study aims to compare the strength of right and left legs and reaction times of soccer players depending on their hand and foot preferences. The study included 92 volunteers chosen from amateur soccer players. The measurements conducted on the subjects were anthropometric characteristics, foot reaction times (sound, light) and right and left foot squat parameters. The t-test was used for statistical procedures. Among the amateur soccer players who participated in this study, it was found that 19.57% used left hand and 67.39% used right hand as preferred. Soccer players using both hands equally were found with a rate of 13.4%. In terms of foot preference, it was found that 22.83% of the participants used left foot and 43.48% of the participants used right foot as preferred. The soccer players using both feet equally was found as 33.70%. No significant difference was found between right handers and left handers in reaction time measurements when the soccer players were grouped by hand preference. When compared with left footed players (0.29 sec), only the right foot sound reaction time of right footed players was significantly shorter (0.21 sec) at p<. 05 level. Statistically significant correlation was found between soccer players’ hand and foot preference at a level of p< 0.01. Left footed players had significantly higher left leg mean squat (37.19 kg) when compared with right footed players (32.27 kg). No significant difference was found between right footed (35.36 kg) and left footed (33.98) subjects in terms of mean of right leg squat. Conclusion: According to the hand preference, the proportion of those who use equally two feet increased. Reaction times and force's squat of the dominant hands and feet were better. Training programs for soccer players planned according to individual characteristics including footedness may result in performance increase and decrease in injury as a result of reduced strength and reaction time asymmetry between legs and arms.

Laryngeal and Manual Reaction Times of Stuttering and Nonstuttering Adults

1981 ◽  
Vol 24 (2) ◽  
pp. 192-196 ◽  
Author(s):  
Alan Reich ◽  
James Till ◽  
Howard Goldsmith
Keyword(s):  
Reaction Time ◽  
Vocal Fold ◽  
Pure Tone ◽  
Reaction Times ◽  
Experimental Conditions ◽  
Motor Pathways ◽  
Vocal Fold Vibration ◽  
Vocal Activity ◽  
The Right ◽  
Previous Reaction

This investigation compared the reaction times of thirteen stuttering and thirteen nonstuttering adults for forefinger button pressing, nonspeeeh vocal initiation, and speech-mode vocal initiation. The stutterers and nonstutterers were matched individually for age, sex, and handedness. The reaction-time stimulus in all response conditions was the offset of a 1000-Hz pure tone. Two of the experimental conditions required button pressing with the right and left. forefingers. The remaining four responses required vocal-fold vibration. The nonspeech vocal activity consisted of inspiratory phonation and expiratory throat clearing. The speech-mode vocal activity required production of the isolated vowel//and the word/p/. The results demonstrated that stuttering and nonstuttering adults differed significantly only on tasks requiring speech phonation. These results are compared to previous reaction-time investigations and related to factors which may influence sensory-motor pathways prior to and during speech.

The Effects of Latex Examination Gloves on Hand Function: A Pilot Study

1995 ◽  
Vol 39 (10) ◽  
pp. 582-585 ◽  
Author(s):  
Benny J. Moore ◽  
Sudheer R. Solipuram ◽  
Michael W. Riley
Keyword(s):  
Grip Strength ◽  
Occupational Safety ◽  
Hand Function ◽  
Manual Dexterity ◽  
Pinch Strength ◽  
Health Administration ◽  
Power Grip ◽  
Latex Glove ◽  
Bare Hand ◽  
Dental Professionals

Over the last decade the use of latex examination gloves by dental professionals has increased significantly. The proliferation in latex glove use is primarily due to recommendations and guidelines established by both the Centers far Disease Control and the Occupational Safety and Health Administration. Because a significant number of dental professionals are wearing latex examination gloves, it is important to understand the limitations and restrictions associated with wearing these gloves. This study investigated the effects of hand condition on three-jaw chuck pinch strength, power grip strength and manual dexterity. Hand condition consisted of three levels: (1) bare hand, (2) hand with a normal sized latex examination glove and (3) hand with a tight fitting latex examination glove. The results of the study indicated that latex examination gloves do not have an effect on three-jaw chuck pinch strength or power grip strength. However the study suggested that ill-fitting latex examination gloves significantly reduce manual dexterity.

The Processing Speed of Visual and Verbal Movement Information by Adults with and Without Down Syndrome

2001 ◽  
Vol 18 (2) ◽  
pp. 156-167 ◽  
Author(s):  
Timothy N. Welsh ◽  
Digby Elliott
Keyword(s):  
Down Syndrome ◽  
Developmental Disabilities ◽  
Processing Speed ◽  
Target Location ◽  
Reaction Times ◽  
Visual Cue ◽  
Aiming Movements ◽  
Rapid Aiming Movements ◽  
Visual Conditions

Previous research has indicated that individuals with Down syndrome (DS) have difficulties processing auditory movement information relative to their peers with undifferentiated developmental disabilities. The present study was conducted to assess whether a model of atypical cerebral specialization could explain these findings. Thirteen adults with Down syndrome (8 men, 5 women), 14 adults with undifferentiated developmental disabilities (7 men, 7 women), and 14 adults without disabilities (8 men, 6 women) performed rapid aiming movements to targets under three conditions: a visual cue at the target location, a visual cue remote from the target location, or a verbal cue. Results revealed that, while the reaction times did not differ between the two groups with disabilities across conditions, the participants with DS, unlike their peers, had significantly longer movement times in the verbal than in two visual conditions. These results are consistent with the model of biological dissociation.

Inhibition of Return without Visual Awareness

Perception ◽  
1996 ◽  
Vol 25 (1_suppl) ◽  
pp. 175-175
Author(s):  
K Watanabe ◽  
S Shimojo
Keyword(s):  
Reaction Time ◽  
Binocular Rivalry ◽  
Inhibition Of Return ◽  
Visual Awareness ◽  
Reaction Times ◽  
Horizontal Line ◽  
Vertical Segment ◽  
Line Segments ◽  
Eye Dominance ◽  
The Right

When a cue and a target are successively presented at the same location, reaction times to discriminate the location of the target are longer than when they are at different locations (inhibition of return: IOR). We found that visual awareness of the cue was not necessary for IOR to occur. Both eyes dichoptically viewed 9 × 9 scattered arrays of vertical or horizontal line segments. To avoid effects of eye dominance and binocular rivalry, cue displays were presented briefly (33, 50, or 200 ms). Three types of cue displays were randomised: (i) no cue: horizontal segments for the left (right) eye and vertical segments for the right (left) eye; subjects perceived scattered binocularly-combined crosses, (ii) binocular (fusible) cue: displays for both eyes had cue elements (a horizontal or vertical segment popping out among orthogonal background segments) and identical interocularly; subjects easily perceived the cue; (iii) dichoptic cue: displays for both eyes had cues at the same location, but all the segments were interocularly orthogonal. Here, because of the brief presentation that horizontal and vertical segments were just combined binocularly, and subjects could see only scattered crosses. Thus, they could not be aware of the cue, which exists at the monocular level. After the cue display disappeared, the target displays [same as the cue display in (ii), but with an independent location of the pop-out target] were presented (ISI=400, 800, or 1200 ms). Reaction time to discriminate location of the target was measured for three subjects who fixated on a fixation point. In our results, IOR took place in conditions (ii) and (iii). This suggests that localisation of the cue occurs without visual awareness, which then leads to IOR.

Sign in / Sign up

Export Citation Format

Share Document