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Reaction Rate

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The rate of reaction is the change in the amount of a reactant or product per unit time. Reaction rates are therefore determined by measuring the time dependence of some property that can be related to reactant or product amounts. Rates of reactions that consume or produce gaseous substances, for example, are conveniently determined by measuring changes in volume or pressure.
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Enabling High Grayscale Resolution Displays and Accurate Response Time Measurements on Conventional Computers

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Relationship between reaction time and electroencephalographic alpha phase.

E CALLAWAY, C L YEAGER

Science (New York, N.Y.)

|December 9, 1960

Summary

This study demonstrates a reliable link between human alpha brain waves and reaction times. By analyzing electroencephalographic activity and visual reaction times at precise intervals, researchers identified a clear relationship.

Area of Science:

Neuroscience
Cognitive Psychology

Background:

Human electroencephalographic (EEG) activity, specifically the 8 to 13 Hz alpha rhythm, is a well-studied brainwave pattern.
Reaction time, a measure of cognitive processing speed, is influenced by various physiological and psychological factors.

Purpose of the Study:

To establish a reliable method for demonstrating the relationship between alpha electroencephalographic activity and simple visual reaction time.
To identify specific phases of the alpha cycle that correlate with slower reaction times.

Main Methods:

Stimuli were presented at precise 10-millisecond intervals within the alpha cycle.
Reaction times were systematically sampled across different phases of the alpha cycle.
Statistical comparisons were made between reaction times at the slowest phase and control phases.

Keywords:

ELECTROENCEPHALOGRAPHY REACTION TIME

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Main Results:

A statistically significant relationship was demonstrated between specific phases of alpha activity and simple visual reaction time.
The phase of the alpha cycle associated with the slowest reaction times was identified.
Sufficient data were collected for reliable statistical comparisons.

Conclusions:

The findings confirm a demonstrable link between alpha brainwave activity and visual reaction speed.
Precise temporal sampling of EEG and reaction time is crucial for revealing these relationships.
This methodology provides a robust approach for further investigating brain-behavior correlations.