Reaction Time Latency Research Articles

The Effects of Plyometric, Tennis-Drills, and Combined Training on Reaction, Lateral and Linear Speed, Power, and Strength in Novice Tennis Players

Reaction time, first-step quickness, lateral (side steps), and forward speed over short distances are important parameters for tennis performance. The aims of this study were: (i) to diagnose the presence of laterality in tennis lateral movements and (ii) to compare the effects of plyometric training (PT), tennis-specific drills training (TDT), and combined training (CT) on performance in tennis-specific movements and power/strength of lower limbs. Sixty-four novice tennis players (21.1 +/- 1.3 years) were equally (n = 16) assigned to a control (C), PT, TDT, or CT. Training was performed 3 times/week for 9 weeks. Testing was conducted before and after training for the evaluation of reaction time (single lateral step), 4-m lateral and forward sprints, 12-m forward sprints with and without turn, reactive ability, power, and strength. There was a significant difference in lateral speed (side-steps) between the 2 sides (P < 0.05). PT, TDT, or CT improved the 4m lateral and forward sprints (P < 0.05). PT and CT improved also the reaction time of the "slow" side (P < 0.05), whereas TDT and CT improved the 12-m sprint performances with and without turn (P < 0.05). Power and strength improved in most tests after PT and CT. Lateral and forward sprints were correlated (r = -0.50 to -0.75; P < 0.05) with power/strength. In conclusion, PT improved fitness characteristics that rely more on reactive strength and powerful push-off of legs such as, lateral reaction time, 4-m lateral and forward sprints, drop jump and maximal force. TDT improved all 4-m and 12-m sprint performances, whereas CT appeared to incorporate the advantage of both programs and improved most tests items. Tennis coaches should be aware that each training regimen may induce more favorable changes to different aspects of fitness.

The effects of a midbrain glioma on memory and other functions: A longitudinal single case study

Our understanding of the effects of midbrain damage on cognition is largely based on animal studies, though there have been occasional investigations of the effects of human midbrain lesions on cognition. This investigation of a rare case of a glioma initially confined to the dorsal midbrain explores the effects of disease progression on IQ, memory, and choice reaction time. Extensive dorsal midbrain damage did not appear to affect IQ and various memory functions (including span, working memory, story recall, and remote memory). Choice reaction time latencies increased, while verbal and spatial learning and long-term memory deteriorated with tumour growth, but it was not clear how far the deterioration reflected midbrain damage or damage outside the midbrain.

Visual attention in adults with developmental dyslexia: Evidence from manual reaction time and saccade latency

Two studies were conducted to investigate visual attention deficits in dyslexia. In Experiment 1, adults with dyslexia and age- and IQ-matched controls completed a simple cueing task; participants responded to briefly presented (20 ms) eccentric targets (3°, 6°, or 9°) with a key press. In Experiment 2, the same participants completed a saccade version of the task, and saccade amplitude, accuracy, and latency were measured. The results revealed comparable performance between the groups on the manual reaction time task. The groups also performed similarly in saccade accuracy and latency. Moreover, neither group showed a visual field asymmetry in their performance, with the exception that adults with dyslexia showed longer saccade latency for 9° targets presented to their left visual field than did controls. However, on the latter measure, the majority (78%) of those with dyslexia performed within the range of the control group. Correlational analyses revealed associations between reading and phoneme awareness in both groups, but phoneme awareness was not associated with visual attention in adult dyslexics. Together, the results are not compatible with a visual attention deficit in adult dyslexia, while they provide support for the phonological deficit hypothesis.

The Right Inferior Frontal Gyrus and Poststroke Aphasia

Recently, a combined repetitive transcranial magnetic stimulation (rTMS) and activation positron emission tomography (PET) study showed essential language function of the right inferior frontal gyrus (IFG) in some right-handed acute poststroke aphasics. We reexamined these patients in the chronic phase to test whether the right IFG remained essential for language performance. We reexamined 9 male right-handed patients, age 41 to 75 years, with aphasia 8 weeks after left hemispheric stroke. rTMS was performed over the maximum activation within the left and right IFG as defined by (15)[O]water PET to interfere with language function. A positive rTMS effect was defined as increased reaction time latency or error rate in the semantic task relative to no stimulation. PET activations of the IFG were observed on the left (2 patients) and bilaterally (7). During rTMS interference over the left IFG, all patients had positive TMS effects, indicating that the left IFG remained essential. Stimulation over the right IFG yielded positive rTMS effects in 2 patients with persisting right IFG activation. Two patients with positive rTMS effects over the right side in the initial study did not show these effects at follow-up. Language performance improved in all patients. Successful regeneration from poststroke aphasia seems to depend more on the integration of available language-related brain regions than on recruiting new brain regions during the rehabilitation process. Restoration of the left hemisphere network seems to be more effective, although in some cases, right hemisphere areas are integrated successfully.

An effective dose of valdecoxib in experimental mouse models of pain

The effects of selective cyclooxygenase-2 (COX-2) inhibitors in biological functions are frequently investigated in animal models. However, there is little data on their analgesic efficacy in experimental animals. This study aimed to determine whether oral gavage of 5 mg/kg valdecoxib in mice is active as an analgesic at this dose and whether it is associated with therapeutic blood levels. A nonselective COX inhibitor, ketorolac, was also investigated for comparison. A total of 106 C57 BL/6N mice were administered a single oral dose of 5 mg/kg of valdecoxib, ketorolac or placebo. The antinociceptive effects of both drugs were tested using hot-plate and formalin tests. For the hot-plate test, reaction time (latency) of the mouse before jumping was recorded. The total time that the mouse spent on licking/biting the injected paw (with dilute formalin) was recorded in the formalin test. Apart from the behavioral tests, plasma concentrations of the drugs at this dose were also determined. Mice were fed with 5 mg/kg of either valdecoxib or ketorolac. Blood samples were collected between 1 and 9 h postingestion. Valdecoxib and ketorolac concentration in the plasma was determined by high performance liquid chromatography with ultraviolet detection (HPLC-UV). Effective antinociception was observed for both drugs in the hot-plate test from 75 min to 2 h after oral dosing. Also, both drug treatments showed a significantly reduced nociceptive response in the second phase in the formalin test (20-30 min after injection). Both valdecoxib and ketorolac showed plasma concentrations comparable to the therapeutic concentrations in humans. A single oral dose of valdecoxib or ketorolac (5 mg/kg) is able to produce a therapeutic analgesic effect in mice.

The Relationship of Aerobic Fitness to Interference Control in Preadolescent Children

Physical inactivity during childhood has steadily increased in recent years, leading to an increased prevalence of being overweight and unfit. Despite a growing body of literature indicating that physical activity may ameliorate or protect against decrements in cognitive performance during adulthood, the relationship between physical inactivity and decrements in cognitive health in children remains absent from public health concerns. PURPOSE: To investigate the relationship between aerobic fitness and executive control cognitive function using a task requiring variable amounts of interference control. METHODS: Forty-eight preadolescent children (Mage = 9.3 yrs) were grouped (i.e., higher-fit, lower-fit) according to their performance on a field test of aerobic capacity using the PACER test of the Fitnessgram, while other demographic variables (e.g., Age, SES, IQ) did not differ between fitness groups. Interference control was measured by event-related brain potential (ERPs) responses and task performance (reaction time, response accuracy) to congruent (e.g., HHHHH) and incongruent (e.g., HHSHH) conditions of an Eriksen flanker task. RESULTS: Results indicated that higher-fit children performed more accurately across conditions of the flanker task when compared to lower-fit children, while group-differences were not observed for reaction time latency. Further, P1 and P3 component amplitudes of the stimulus-locked ERP were larger for higher- compared to lower-fit children across conditions of the flanker task indicating that fitness may be associated with early visual attention processes as well as the allocation of attentional resources to working memory in the stimulus environment. CONCLUSION: The findings indicate that aerobic fitness may non-selectively benefit cognitive function on tasks requiring variable amounts of interference control during preadolescent childhood, and suggest that fitness may relate to improved cognitive health.

Stimulus intensity modifies saccadic reaction time and visual response latency in the superior colliculus

Performance in a reaction time task can be strongly influenced by the physical properties of the stimuli used (e.g., position and intensity). The reduction in reaction time observed with higher-intensity visual stimuli has been suggested to arise from reduced processing time along the visual pathway. If this hypothesis is correct, activity should be registered in neurons sooner for higher-intensity stimuli. We evaluated this hypothesis by measuring the onset of neural activity in the intermediate layers of the superior colliculus while monkeys generated saccades to high or low-intensity visual stimuli. When stimulus intensity was high, the response onset latency was significantly reduced compared to low-intensity stimuli. As a result, the minimum time for visually triggered saccades was reduced, accounting for the shorter saccadic reaction times (SRTs) observed following high-intensity stimuli. Our results establish a link between changes in neural activity related to stimulus intensity and changes to SRTs, which supports the hypothesis that shorter SRTs with higher-intensity stimuli are due to reduced processing time.

Age-related Changes of Reaction Time and p300 for Low-contrast Color Stimuli: Effects of Yellowing of the Aging Human Lens

We measured reaction time (RT), P300, and subjective evaluation for color Landolt-Cs with a gray color background presented on a CRT display. Seven young and 7 elderly subjects (mean ages: 21.6 and 68.4 years, respectively) participated, and the young subjects wore glasses with filters simulating spectral transmittance of an aging human lens as a test condition. The results for young subjects not wearing the filters showed that RT and P300 latency are constant among different test colors. In contrast, the results for elderly subjects showed that RT and P300 varied substantially depending upon the test colors and RT and P300 latency became longer than those of young subjects, particularly for gray and blue stimuli. In addition, the results for the young subjects with filters showed tendencies similar to those in elderly subjects. These results indicate that the yellowing of the human lens strongly influences reaction time and cognition time for color targets, suggesting that wearing the filters enables the young to simulate RT qualitatively as well as visibility of the elderly because both the simulated filter and the aging human lens modify the effective luminance, effective luminance contrast and effective color difference between the color target and the background on the retina. We also found that the reciprocal of RT and P300 latency could be expressed in a multiple regression model consisting of effective luminance, effective luminance contrast, effective color difference and age. Absolute values of RT and P300 latency in young subjects with filters, however, did not quantitatively coincide with those of the elderly subjects. There were differences of RT and P300 latency between the young with filters and the elderly, indicating that higher order age-related delay could be involved.

Dissociable effects in reaction time performance after unilateral cerebral infarction: A comparison between the left and right frontal cortices in rats

Reaction time performance reflects the speed of information processing, both in humans and lower vertebrates like the rat. The present study compared reaction time performance in rats following unilateral infarction to the frontal cortex. The objective was to model cognitive impairment as it is seen in humans after stroke. Rats were trained in a reaction time paradigm, after which unilateral cortical infarction was induced photochemically. Reaction time performance was differentially affected after unilateral infarction to either the left or right frontal cortex, whereas sham operation did not result in a significant alteration in reactivity. An overall increase in reaction time of about 10% was present at 4 weeks after frontal infarction. In addition, a lateralized reaction time deficit occurred very early after right frontal infarction as an increase of 10–15% in trials directed towards the contralesional side. Additional analyses showed that these reaction time deficits can be explained differently: the former as a gradual and general decrease in the speed of information processing, whereas the latter shows specific impairment to initiate a contralateral motor response. The former matches well with the mental slowing observed in stroke patients, whereas the latter resembles a neglect phenomenon. We conclude that measuring reaction time performance after frontal cortical infarction in rats could offer a useful tool to model particular human cognitive impairments following cerebral infarction.

Development of a behavioral task measuring reward “wanting” and “liking” in rats

It has been suggested that reward “wanting” and “liking” are mediated by separable brain systems. To facilitate neuropharmacological and neurophysiological research on this issue we developed a behavioral task with putative measures of reward “wanting” and “liking” available on a trial-by-trial basis. We were able to test whether our measures were sensitive to changes in thirsty rats' “wanting” and “liking” of liquid reward by manipulating its delay, taste and volume. We found that three of our putative “wanting” measures (anticipatory errors, reaction time and reward collection latency) were affected by upcoming reward delay and/or taste and our putative “liking” measure (post-reward licking) was sensitive to variations in reward taste and volume. To cross-validate our measures with previous pharmacological work we tested rats following acute, systemic administration of drug compounds that globally enhance serotonin and noradrenaline (imipramine), dopamine (GBR 12909) and opioid (morphine) function. Imipramine augmented the effects of delay and taste on reward “wanting”, GBR 12909 attenuated the effects of delay on reward “wanting” and the effects of taste on reward “liking”, and morphine reduced the effect of delay on a measure of reward “wanting”. Since morphine failed to affect reward “liking” but has been previously found to enhance reward “liking” in taste reactivity tests, our measure requires further pharmacological validation. However, this task shows potential to assess the specific neural mechanisms that contribute to the impact of reward parameters on “wanting” and “liking”.

A neurophysiological study of the detrimental effects of alprazolam on human action monitoring

In order to adapt their behavior to different unexpected situations, humans need to be able to monitor their performance and detect and correct errors. Benzodiazepines have long been shown to impair performance in humans, but the performance-related neurophysiological processes targeted by these drugs remain largely unknown. In the present article, we assessed the impact of alprazolam administration on relevant aspects of action monitoring, i.e., the monitoring of response conflict and the detection and correction of errors by means of neurophysiological measures. Multichannel event-related brain potentials (ERPs) were recorded to assess the impact of the benzodiazepine alprazolam (0.25 mg and 1.00 mg) on action monitoring and motor preparation in a group of twelve healthy male volunteers who participated in a double-blind cross-over placebo-controlled clinical trial involving a letter flanker task. Error detection was evaluated using the error-related negativity (ERN); response conflict on correct trials was measured by means of the N2 amplitude difference between congruent and incongruent trials; motor preparation was assessed by means of the lateralized readiness potentials (LRPs); and post-error adjustments were assessed by measuring post-error slowing in reaction time. Alprazolam significantly reduced the amplitude of the ERN and the number of corrective responses and increased reaction time and LRP latencies. The drug had no effect on amplitude differences in the N2 component between congruent and incongruent trials or on post-error slowing. Thus, alprazolam was shown to affect brain correlates of error detection (ERN) and motor preparation (LRPs), while it did not disturb conflict monitoring on correct trials (N2) or post-error adjustments of behavior.

Role of the Contralateral Inferior Frontal Gyrus in Recovery of Language Function in Poststroke Aphasia

Functional neuroimaging studies have demonstrated right inferior frontal gyrus (IFG) activation in poststroke aphasia. It remains unclear whether this activation is essential for language performance. We tested this hypothesis in a positron emission tomography (PET) activation study during a semantic task with repetitive transcranial magnetic stimulation (rTMS) on right-handed patients experiencing poststroke aphasia and examined whether rTMS stimulation over the right and left IFG would interfere with language performance. Eleven patients with left-sided middle cerebral arterial infarction, 50 to 75 years of age, were tested with the Aachen Aphasia Test Battery and underwent (15)O-H2O PET activation during a semantic task within 2 weeks after stroke. PET activation images were coregistered to T1-weighted MRIs. Stimulation sites were determined on renderings of head and brain over the maximum activation within left and right IFG. rTMS was performed with 20% maximum output (2.1 T), 10-s train duration, at 4 Hz frequency. A positive rTMS effect was defined as an increased reaction time latency or error rate in the semantic task. PET activations of the IFG were observed on the left (3 patients) and bilaterally (8 patients). Right IFG stimulation was positive in 5 patients with right IFG activation, indicating essential language function. In a verbal fluency task, these patients had a lower performance than patients without right-sided TMS effect. In some poststroke aphasics, right IFG activation is essential for residual language function. However, its compensatory potential seems to be less effective than in patients who recover left IFG function. These results suggest a hierarchy in recovery from poststroke aphasia and a (limited) compensatory potential of the nondominant hemisphere.

Late event-related potentials and movement complexity in young adults with Down syndrome

Objectives. – Through event-related potential (ERP) recording, to better understand the perceptive-motor slowness in adults with Down syndrome (DS); in particular, to assess whether motor preparation influences the speed of allocation of perceptual attention as reflected by the P3 latency. Patients and methods. – ERPs were obtained in adults with and without DS through an auditory oddball paradigm under a passive and two active (simple vs. complex motor response) conditions. Reaction times (RTs) were recorded in the two active conditions. Results. – There was no influence of movement complexity on either RT or P3b latency in the control group. In the DS group, RT was delayed under simple vs. complex conditions whereas P3b latency was not affected. N2a and N2b were often missing in DS individuals. Conclusion. – Motor preparation processes per se rather than interaction with perceptual attention could be defective in individuals with DS when the motor component of the response is minimal.

THE DOSE-DEPENDENT EFFECT OF METHYLPHENIDATE ON PERFORMANCE, COGNITION AND PSYCHOPHYSIOLOGY

The effects of methylphenidate (MPH) on 32 healthy human male volunteers (aged 18 to 25 years, mean age=22.26) were examined using a within-subject design. Each participant attended six testing periods, held once per week. Within each testing period, three repeat testing sessions were undertaken: pre-medication, on-medication and two hours post-medication. In these sessions, dose was manipulated (placebo, 5 mg, 15 mg or 45 mg) according a double-blind placebo design. In this report, we focus on behavioral, autonomic arousal (heart rate, skin conductance) and psychophysiological (ERP) data acquired during the working memory task. We found increased autonomic arousal (heart rate, skin conductance and blood pressure) with MPH. A linear reduction in reaction time, omission errors and target P3 latency, and a corresponding increase in background P3 amplitude was observed with increased MPH dose. The relationship between these measures supported an increase in performance and underlying brain function with MPH. To our knowledge, this is the first paper to use behavioral, arousal and electrophysiological measures in an integrative approach to study the effects of MPH on healthy adults.

Exercise Leads to Faster Postural Reflexes, Improved Balance and Mobility, and Fewer Falls in Older Persons with Chronic Stroke

To determine the effect of two different community-based group exercise programs on functional balance, mobility, postural reflexes, and falls in older adults with chronic stroke. A randomized, clinical trial. Community center. Sixty-one community-dwelling older adults with chronic stroke. Participants were randomly assigned to an agility (n=30) or stretching/weight-shifting (n=31) exercise group. Both groups exercised three times a week for 10 weeks. Participants were assessed before, immediately after, and 1 month after the intervention for Berg Balance, Timed Up and Go, step reaction time, Activities-specific Balance Confidence, and Nottingham Health Profile. Testing of standing postural reflexes and induced falls evoked by a translating platform was also performed. In addition, falls in the community were tracked for 1 year from the start of the interventions. Although exercise led to improvements in all clinical outcome measures for both groups, the agility group demonstrated greater improvement in step reaction time and paretic rectus femoris postural reflex onset latency than the stretching/weight-shifting group. In addition, the agility group experienced fewer induced falls on the platform. Group exercise programs that include agility or stretching/weight shifting exercises improve postural reflexes, functional balance, and mobility and may lead to a reduction of falls in older adults with stroke.

Neuroimaging-guided rTMS of the left inferior frontal gyrus interferes with repetition priming

Neuroimaging studies of right-handed normal volunteers under semantic word generation tasks have consistently reported left lateralized activation of the anterior inferior frontal gyrus (ifg) which decreased during task repetition. This repetition-related activation decrease has been interpreted as the neurophysiological correlate of repetition priming, a mechanism of implicit memory for initial semantic processing. We interfered with left lateralized ifg activation, as identified by O-15-water PET activation, using repetitive transcranial magnetic stimulation (rTMS) in five right-handed male normal subjects, once using new (unprimed) nouns and once using known (primed) nouns for the procedure. All five subjects exhibited clear left lateralized activations of the triangular part of the left ifg in the PET studies. In all subjects, reaction time latencies were significantly longer during rTMS over the activation sites in the left ifg as compared to latencies off stimulation. Latencies were not affected during stimulation of the right ifg or over the vertex. These effects were observed within the group and in each individual, only if lists of primed nouns were used in the verb-generation task. In conclusion, these results demonstrate that the anterior part of the left ifg is not only involved in semantic processing, but is also essential for repetition priming on semantic tasks since successful interference with rTMS was only observed if lists of primed words were used for the generation task.

Inconsistency in serial choice decision and motor reaction times dissociate in younger and older adults

Intraindividual variability (inconsistency) in reaction time (RT) latencies was investigated in a group of younger ( M = 25.46 years) and older ( M = 69.29 years) men. Both groups performed 300 trials in 2-, 4-, and 8-choice RT conditions where RTs for decision and motor components of the task were recorded separately. A dissociation was evident in that inconsistency was greater in older adults for decision RTs when task demands relating to the number of choices and fatigue arising from time-on-task were high. For younger persons, a weak trend toward greater inconsistency in motor RTs was evident. The results are consistent with accounts suggesting that inconsistency in neurobiological mechanisms increases with age, and that attentional lapses or fluctuations in executive control contribute to RT inconsistency.

Impaired visuospatial divided attention in the spontaneously hypertensive rat

The spontaneously hypertensive rat (SHR) is a potential rodent model for the impulsive, inattentive and hyperactive aspects of attention deficit/hyperactivity disorder. Impaired response inhibition and deficits of visual attention are demonstrable phenotypes of SHR (compared with normotensive Wistar–Kyoto rats), and alterations of catecholaminergic transmission in the prefrontal cortex are thought to contribute to aspects of the phenotypic differences. Here, we investigated the attentional performance of SHR and WKY, using a lateralized reaction time task, a behavioral measure of visuospatial divided attention. SHR acquired the conditional rule of the task normally but exhibited deficient accurate performance when stimulus durations were ultimately decreased to less than 1 s. The alpha-2 agonist guanfacine, which is used clinically to treat symptoms of AD/HD, was without effect on the performance of either SHR or Wistar–Kyoto rats. These data indicate that SHR exhibit performance deficits on a test of visual attention but do not resolve the predictive validity this putative model for AD/HD.

Cross-Sectional Change of Biological Maturity and Neuromuscular Response Ability in Adolescent Soccer Players

2118 It has been recognized that during adolescence skilled athletes develop a faster neuromuscular response time than non-athletes. Since large individual differences can appear between skeletal maturity and chronological age (CA), the relationship between skeletal maturity and the development of neuromuscular response is unclear. PURPOSE: The purpose of this study was to clarify the relation between development of biological maturity and neuromuscular response ability evaluated from reaction time (RT), premotor time (PMT) and negative waveform latency obtained between 150 to 400 msec later from the reaction stimulus at the electroencephalogram (N200). METHODS: Eighteen male adolescent soccer players (age range: 10.3 to 12.9 years) from the Japanese professional soccer club participated in this study. Biological maturity was evaluated from X-ray of left hand and wrist according to skeletal age (SA) using TWII methods. Visual go/no-go task was employed and subjects were asked to respond to the target stimuli by pushing both hand and foot response switches. PMT of the fiexor pollicis longus and gastrocnemius medialis was also measured. N200 was recorded at the central scalp area based on the international 10–20 methods. RESULTS: The RT as measured from the foot switch shortened from 10 to 12 years of age (536.8 ± 51.7, 501.7 ± 108.1, 448.0 ± 33.3 msec respectively) and it showed a stronger correlation to SA (r = −0.67, p<0.01) as compared to CA (p = −0.49, p<0.05). PMT of the hand and foot correlated more significantly to SA (r = −0.62, p<0.01; r = −0.71, p<0.001) than that of CA (r = −0.59, p<0.05; r = −0.59, p<0.05). It was noteworthy that development of N200 had significant correlation to SA (r = −0.51, p<0.05), however it did not well correlate to CA. CONCLUSIONS: The results of this study indicate the development of neuromuscular response ability such as premotor time and N200 may be influenced by the development of biological maturity (skeletal age) in adolescent soccer players. In conclusion, considering the biological maturity is necessary to investigate the development of neuromuscular response ability in adolescent.

Cross-Sectional Change of Biological Maturity and Neuromuscular Response Ability in Adolescent Soccer Players

2118 It has been recognized that during adolescence skilled athletes develop a faster neuromuscular response time than non-athletes. Since large individual differences can appear between skeletal maturity and chronological age (CA), the relationship between skeletal maturity and the development of neuromuscular response is unclear. PURPOSE: The purpose of this study was to clarify the relation between development of biological maturity and neuromuscular response ability evaluated from reaction time (RT), premotor time (PMT) and negative waveform latency obtained between 150 to 400 msec later from the reaction stimulus at the electroencephalogram (N200). METHODS: Eighteen male adolescent soccer players (age range: 10.3 to 12.9 years) from the Japanese professional soccer club participated in this study. Biological maturity was evaluated from X-ray of left hand and wrist according to skeletal age (SA) using TWII methods. Visual go/no-go task was employed and subjects were asked to respond to the target stimuli by pushing both hand and foot response switches. PMT of the fiexor pollicis longus and gastrocnemius medialis was also measured. N200 was recorded at the central scalp area based on the international 10–20 methods. RESULTS: The RT as measured from the foot switch shortened from 10 to 12 years of age (536.8 ± 51.7, 501.7 ± 108.1, 448.0 ± 33.3 msec respectively) and it showed a stronger correlation to SA (r = −0.67, p<0.01) as compared to CA (p = −0.49, p<0.05). PMT of the hand and foot correlated more significantly to SA (r = −0.62, p<0.01; r = −0.71, p<0.001) than that of CA (r = −0.59, p<0.05; r = −0.59, p<0.05). It was noteworthy that development of N200 had significant correlation to SA (r = −0.51, p<0.05), however it did not well correlate to CA. CONCLUSIONS: The results of this study indicate the development of neuromuscular response ability such as premotor time and N200 may be influenced by the development of biological maturity (skeletal age) in adolescent soccer players. In conclusion, considering the biological maturity is necessary to investigate the development of neuromuscular response ability in adolescent.