Measurement of reaction times in healthy subjects

Summary

The number of alternative stimuli plus the number of alternative responses and the reaction times are strongly related. But the exact relation is questionable. The law of Hick postulates a logarithmic fit and has dominated the discussion. The question arises whether new data fit Hick’s law or some other law. Five subjects with nearly 10,000 measurements were used to answer this question. A linear relation was found between reaction time and the number of alternatives when the number of alternatives is not too high. With more alternatives, the relationship is clearly non-linear.