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The effect on reaction time (RT) and movement time (MT) of remembering which one of several targets to move to was investigated in 18 participants who completed 416 trials in each task. On each trial, participants moved their index finger from a central, illuminated switch (the stimulus) to one of eight targets located on the circumference of a 6 cm radius circle. A visual cue (illumination of the target) informed the participant of the appropriate target. In the memorised delay task, the cued target was lit for 300 ms followed by a variable (450-750 ms) foreperiod during which the participant was required to remember the location of the target until the stimulus light was extinguished. In the non-memorised delay task, the target remained lit during the entire foreperiod (750-1050 ms) until the response was completed. At the "go" signal (stimulus light extinguished) participants moved as quickly and accurately as possible to the cued target. Both RT and MT were significantly (p<0.05) longer in the memorised delay task. The increase in RT shows that remembering which target imposed a greater load on motor preparation even though all the information needed for preparing the response was presented in the cue at the beginning of each trial. The increase in MT raises the possibility that movement execution was also programmed during motor preparation.

Franklin Henry's "memory drum" theory of neuromotor reaction (Henry & Rogers, 1960) was one of the most influential studies of the response programming stage of information processing. The paper is the most-cited study ever published in the "Research Quarterly for Exercise and Sport." However, few people know there is a noteworthy error in the paper, namely in the description of the C movement, the most complicated of the three responses studied. Henry himself was unaware of the error for nearly 20 years after the paper's publication. The purpose of our paper is to accord the factual record its due respect by revealing the history about the error and its correction. The data are in the form of the original 1960 paper which describes the C movement, a paper by Howell (1953), and personal letters from Henry dating from 1979, when the error was first discovered, and continuing through 1986. In one letter, Henry attributed the error to a mild and specific form of aphasia, manifested by word reversals, from which he suffered throughout his scholarly life. Such a revelation makes the career of this remarkable scholar even more remarkable. (Contains 2 figures and 1 note.)

In the monkey, reaction time in a precued delayed response task was found to be faster when the animals had to remember the precue than when it was continually available (Smyrnis, Taira, Ashe, & Georgopoulos, 1992). We investigated whether this reflects a general principle that applies to all types of precued tasks. However, we found the opposite result in a simpler task in humans. Our findings suggest that the beneficial effect of a memory requirement on reaction time in the monkey may reflect an effect of task difficulty, rather than a fundamental process involved in all precued movement tasks. [ABSTRACT FROM AUTHOR]

The effect of foreperiod length on reaction time in memorized (MM) and nonmemorized (NM), precued, delayed responses was investigated. Six subjects participated in one long and one short foreperiod schedule testing session. An aiming task, using elbow supination/pronation, in response to a visual stimulus was employed. In the MM condition, target spatial information was available for a fraction of the foreperiod duration. In the NM condition, target information was available continuously until the subject attained the target position. Subjects responded with a significantly longer latency in the long foreperiod schedule. Within each foreperiod schedule, the shortest foreperiod resulted in significantly longer reaction time. However, the absolute value of foreperiod did not have a major effect on reaction time latency. Memorization and nonmemorization conditions did not affect reaction time. [ABSTRACT FROM AUTHOR]