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Factors influencing the latency of simple reaction time.

Woods DL, Wyma JM, Yund EW, Herron TJ, Reed B - Front Hum Neurosci (2015)

Bottom Line: Mean SRT latencies were short (231, 213 ms when corrected for hardware delays) and increased significantly with age (0.55 ms/year), but were unaffected by sex or education.SRT latencies increased with age while SDT latencies remained stable.Precise computer-based measurements of SRT latencies show that processing speed is as fast in contemporary populations as in the Victorian era, and that age-related increases in SRT latencies are due primarily to slowed motor output.

View Article: PubMed Central - PubMed

Affiliation: Human Cognitive Neurophysiology Laboratory, Veterans Affairs Northern California Health Care System, Martinez CA, USA ; The Department of Neurology, University of California Sacramento, Davis CA, USA ; Center for Neurosciences, University of California Davis, Davis CA, USA ; Center for Mind and Brain, University of California Davis, Davis CA, USA.

ABSTRACT
Simple reaction time (SRT), the minimal time needed to respond to a stimulus, is a basic measure of processing speed. SRTs were first measured by Francis Galton in the 19th century, who reported visual SRT latencies below 190 ms in young subjects. However, recent large-scale studies have reported substantially increased SRT latencies that differ markedly in different laboratories, in part due to timing delays introduced by the computer hardware and software used for SRT measurement. We developed a calibrated and temporally precise SRT test to analyze the factors that influence SRT latencies in a paradigm where visual stimuli were presented to the left or right hemifield at varying stimulus onset asynchronies (SOAs). Experiment 1 examined a community sample of 1469 subjects ranging in age from 18 to 65. Mean SRT latencies were short (231, 213 ms when corrected for hardware delays) and increased significantly with age (0.55 ms/year), but were unaffected by sex or education. As in previous studies, SRTs were prolonged at shorter SOAs and were slightly faster for stimuli presented in the visual field contralateral to the responding hand. Stimulus detection time (SDT) was estimated by subtracting movement initiation time, measured in a speeded finger tapping test, from SRTs. SDT latencies averaged 131 ms and were unaffected by age. Experiment 2 tested 189 subjects ranging in age from 18 to 82 years in a different laboratory using a larger range of SOAs. Both SRTs and SDTs were slightly prolonged (by 7 ms). SRT latencies increased with age while SDT latencies remained stable. Precise computer-based measurements of SRT latencies show that processing speed is as fast in contemporary populations as in the Victorian era, and that age-related increases in SRT latencies are due primarily to slowed motor output.

No MeSH data available.


Stimulus detection time (SDT) as a function of age. SDT was derived by subtracting the movement initiation time in a speeded finger tapping test from SRTs. The linear trend line is from Experiment 1 data.
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Figure 4: Stimulus detection time (SDT) as a function of age. SDT was derived by subtracting the movement initiation time in a speeded finger tapping test from SRTs. The linear trend line is from Experiment 1 data.

Mentions: We found a significant correlation [r = 0.25 (range 0.20–0.30), t(1,1469) = 9.89, p < 0.0001] between SRT latencies measured in the current experiment and MIT, the time needed to depress the response button that had been previously measured in a self-paced finger tapping task conducted on the same day (Hubel et al., 2013a). SDT latencies, obtained by subtracting MIT latencies from SRT latencies, averaged 131.2 ms (SD = 30.2 ms). Figure 4 shows SDT latencies as a function of age. Unlike SRT latencies, SDT latencies did not increase with age [r = -0.02], nor did they differ significantly between male and female subjects [r = 0.05]. Finally, comparisons of the correlations of age with MIT latency and age with SRT latency showed significantly larger correlations of age with MIT latency [r = 0.33 vs. r = 0.24, z = 2.65, p < 0.01].


Factors influencing the latency of simple reaction time.

Woods DL, Wyma JM, Yund EW, Herron TJ, Reed B - Front Hum Neurosci (2015)

Stimulus detection time (SDT) as a function of age. SDT was derived by subtracting the movement initiation time in a speeded finger tapping test from SRTs. The linear trend line is from Experiment 1 data.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4374455&req=5

Figure 4: Stimulus detection time (SDT) as a function of age. SDT was derived by subtracting the movement initiation time in a speeded finger tapping test from SRTs. The linear trend line is from Experiment 1 data.
Mentions: We found a significant correlation [r = 0.25 (range 0.20–0.30), t(1,1469) = 9.89, p < 0.0001] between SRT latencies measured in the current experiment and MIT, the time needed to depress the response button that had been previously measured in a self-paced finger tapping task conducted on the same day (Hubel et al., 2013a). SDT latencies, obtained by subtracting MIT latencies from SRT latencies, averaged 131.2 ms (SD = 30.2 ms). Figure 4 shows SDT latencies as a function of age. Unlike SRT latencies, SDT latencies did not increase with age [r = -0.02], nor did they differ significantly between male and female subjects [r = 0.05]. Finally, comparisons of the correlations of age with MIT latency and age with SRT latency showed significantly larger correlations of age with MIT latency [r = 0.33 vs. r = 0.24, z = 2.65, p < 0.01].

Bottom Line: Mean SRT latencies were short (231, 213 ms when corrected for hardware delays) and increased significantly with age (0.55 ms/year), but were unaffected by sex or education.SRT latencies increased with age while SDT latencies remained stable.Precise computer-based measurements of SRT latencies show that processing speed is as fast in contemporary populations as in the Victorian era, and that age-related increases in SRT latencies are due primarily to slowed motor output.

View Article: PubMed Central - PubMed

Affiliation: Human Cognitive Neurophysiology Laboratory, Veterans Affairs Northern California Health Care System, Martinez CA, USA ; The Department of Neurology, University of California Sacramento, Davis CA, USA ; Center for Neurosciences, University of California Davis, Davis CA, USA ; Center for Mind and Brain, University of California Davis, Davis CA, USA.

ABSTRACT
Simple reaction time (SRT), the minimal time needed to respond to a stimulus, is a basic measure of processing speed. SRTs were first measured by Francis Galton in the 19th century, who reported visual SRT latencies below 190 ms in young subjects. However, recent large-scale studies have reported substantially increased SRT latencies that differ markedly in different laboratories, in part due to timing delays introduced by the computer hardware and software used for SRT measurement. We developed a calibrated and temporally precise SRT test to analyze the factors that influence SRT latencies in a paradigm where visual stimuli were presented to the left or right hemifield at varying stimulus onset asynchronies (SOAs). Experiment 1 examined a community sample of 1469 subjects ranging in age from 18 to 65. Mean SRT latencies were short (231, 213 ms when corrected for hardware delays) and increased significantly with age (0.55 ms/year), but were unaffected by sex or education. As in previous studies, SRTs were prolonged at shorter SOAs and were slightly faster for stimuli presented in the visual field contralateral to the responding hand. Stimulus detection time (SDT) was estimated by subtracting movement initiation time, measured in a speeded finger tapping test, from SRTs. SDT latencies averaged 131 ms and were unaffected by age. Experiment 2 tested 189 subjects ranging in age from 18 to 82 years in a different laboratory using a larger range of SOAs. Both SRTs and SDTs were slightly prolonged (by 7 ms). SRT latencies increased with age while SDT latencies remained stable. Precise computer-based measurements of SRT latencies show that processing speed is as fast in contemporary populations as in the Victorian era, and that age-related increases in SRT latencies are due primarily to slowed motor output.

No MeSH data available.