Jensen has reported several studies that have demonstrated a significa
nt relationship between measures of choice reaction time (RT) and IQ,
and has concluded that speed of information processing is causally rel
ated to the development of intelligence. All of these studies have emp
loyed a procedure that separates decision time (DT) from movement time
(MT), and which assumes that the time from stimulus onset to the rele
ase of a home key accurately measures DT. Recently, Smith and Carew (1
987) provided evidence that some subjects use task strategies which sh
orten and thus bias their DTs. Such a strategy may invalidate speed of
information processing explanations of past DT-IQ results. The presen
t study replicates the Smith and Carew finding, and provides prelimina
ry information on the relationship between both masked and unmasked RT
measures and intelligence test scores. The results indicate that the
addition of a mask (to prevent strategy use in RT tasks) adds a consta
nt amount of time to the average 1-, 2-, 4-, and 8-choice DTs, and doe
s not change the slope of the function relation mean DT across stimulu
s complexity. As significant negative correlations between mean DT and
IQ (Wechsler Adult Intelligence Scale - Revised and the Raven Advance
d Progressive Matrices) were observed in both masked and unmasked RT c
onditions, it is suggested that: strategy use in this procedure does n
ot cause the relationship between DT and IQ reported in previous exper
iments. MT variables and IQ were negatively correlated. Slope of mean
DT across choice and IQ were not significantly correlated. These resul
ts suggest that the Hick information processing model of intelligence
should be replaced.