Biomedical subjects

J T Quinn

Publications and source records attributed to J T Quinn.

10 recordsLinked to original sources

PubMed1983

Time requirements of changes in program and parameter variables in rapid ongoing movements.

Two experiments investigated the differences in processing time requirements of two types of modifications of a rapid ongoing movement. In response to a signal presented at either 0, 100, or 200 msec after initiation of a 400-msec horizontal arm movement, subjects attempted to either increase the speed of the movement or to reverse it. EMG modification latencies were shorter in the former condition than in the latter indicating a difference in processing-time requirement between modification types. The results support the generalized motor program hypothesis of Pew (1974) and Schmidt (1976) in that increasing the speed of an ongoing movement may require modification of a parameter variable while reversing movement direction requires the implementation of a new motor program.

Journal Article↗

PubMed1980

Target-size influences on reaction time with movement time controlled.

The variable that affect motor programming time may be studied by changing the nature of the response and measuring the subsequent changes in reaction time (RT). One notion of motor programming suggests that aiming responses with reduced target size and/or increased target amplitude require more "complex" motor programs that require longer RTs. In a series of five experiments which movement time (MT) was experimentally varied target size neither influences RT when the movement amplitude was 2 or 30 cm nor when the target sizes differed by as much as a factor of 16:1. Increasing the movement amplitude from 15 to 30 cm also had no influence on RT. Movement time, however, did affect RT, with 200-msec movements having longer RTs than 120-msec movements. Target size and movement amplitude did not appear to be factors that influence programming time or program complexity.

Journal Article↗

PubMed1979