A two-state model of simple reaction time

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on RT is the attempt by Baumeister and Joubert(1969). They varied
the relative frequency of the various FPs to manipulate the
expectancy. But, the FPs used by them were 2,4,8,16 sec. These
FPs are highly discriminable so that we suspect that the subject
might be unduly forced to develop the expectancy during the
experiment.
2) In some experiments reviewed by Niemi and Naatanen(1981),
FPs were very short, i.e., shorter than 1 sec, and in others,
they were very long, i.e., longer than 10 sec. For too short FPs,
the subject may not be able to prepare his motor system before the
presentation of the stimulus when no warning signal is used.
When too long FPs are used, we suspect that multiple preparation
may be invoked, i.e., the process of simple reaction for longer
FPs may not be the same as that for other FPs.
3) Analyzing the data from trained and unexperienced subjects
separately, Naatanen and Merisalo(1977) found differences between
the two kinds of subjects in the sensitivity of the RT to
manipulations of experimental conditions. In general, as to
the kind of the subjects, experimenters used trained subjects or