Mary Lou Norrie

Practice Effects on Reaction Latency for Simple and Complex Movements

Abstract Henrys “Memory Drum” theory of neuromotor reaction was applied to the learning of simple and complex movements having such short duration that feedback in its classical monitoring aspect was excluded. The theory implied that the amount of program simplification and reorganization in the learning of a simple movement is small and occurs early in the practice curve, while that for a more complex movement is larger and requires more practice to reach the limits of simplification. Subjects were college women divided into simple movement and complex movement groups of 51 each. The simple movement involved a forward movement of the arm while the complex movement required subjects to change the direction of the arm movement twice. Each subject had 50 trials on her task. Since according to theory the organization of the neuromotor program takes place before the movement starts, reaction times were used to indicate time for program organization. Movement time data was also collected. The complex movement...

Effects of Movement Complexity on Choice Reaction and Movement Times

Abstract Two groups of 24 college age men volunteers from activity classes performed a choice reaction time task. One group performed using a simple 4-in. movement from the reaction button to the appropriate response button. The other group performed using a complex movement in which they first moved forward 12 in. to slap a button and then returned to the appropriate response button. Both groups performed 20 trials under each choice condition (1, 2, and 4 choices). For the complex movement tasks the one choice reaction time was significantly faster than the multiple choice reaction times which did not differ significantly. The complex movement group was somewhat slower in movement time under multiple choice conditions. As the number of choices increased the effect of increasing movement complexity on reaction time lessened.

Effects of Unequal Distances and Handedness on Timing Patterns for Simultaneous Movements of Arms and Legs

Abstract Previous research on the ability of people to perform simultaneous movements involving speed and accuracy showed a consistent movement pattern whenever the two limbs moved unequal distances. It was not clear whether the pattern was a function of handedness or the greater distance moved by the preferred hand. The purpose of the present experiment was to study the effect of distance and handedness on movement patterns. Five movement tasks using two simultaneous movements of arms and/or legs were used. The data indicated that for the tasks involving unequal distances the limb having the greater distance to move starts first and finishes last. Also, individual variability for contact time difference (failure to finish the two parts of the movement simultaneously) was greater than that for starting time difference (failure to start both parts together).

Timing of Two Simultaneous Movements of Arms and Legs

Abstract The ability of people to perform simultaneous movements involving speed and accuracy, and the relationships among the several time measures for these movements were studied. Five movement tasks using two simultaneous movements of arms and legs were performed. Reliability of time measures ranged between 0.830 and 0.988. There were no significant differences between the two tasks involving an arm and a leg. Reaction time for tasks involving an arm and leg was slower than for tasks involving two arms. An increase in task complexity resulted in an increase in starting time difference and contact time difference. Common variance between tasks for several time measures was relatively high. For all tasks, except the one using identical movements for the two arms, a consistent movement pattern was found in which the right hand started first and finished last.

Number of Reinforcements and Memory Trace for Kinesthetically Monitored Force Reproduction.

Abstract The effect of the number of reinforcements on the memory trace for a kinesthetically monitored force reproduction task was studied. Sixty college women were divided by a balanced order into three groups of 20 each. One group had one reinforcement, one had five reinforcements, and the third had nine reinforcements. The reproduction attempt was either immediate or after a 30-sec. delay. Analysis of variance for constant error indicated that multiple reinforcements improved the accuracy of performance for immediate reproduction but that the improvement was not retained over a retention interval of 30 sec. The tendency to overshoot the standard occurred for both the immediate and delayed reproduction conditions.

Short-Term Memory Trace Decay in Kinesthetically Monitored Force Reproduction

Abstract The decay of the memory trace for intervals of 1/2 min., 1 1/2 min., and 4 min. between the test stimulus and the reproduction trial was studied for a force reproduction task in which the amount of movement was very small, .13 in. The subject pushed against a handle attached to the top of a steel bar with the preferred hand. Sixty-three women volunteers from college physical education classes performed the experiment. For Part A all subjects first had four trials in which the reproduction was immediate (the control condition). Then they were divided randomly into three subgroups of 21, and each subgroup was assigned to one of the three retention intervals (experimental conditions) for four more trials. In Part B the whole experiment was repeated. For both absolute and algebraic error, analysis of covariance indicated no significant differences at the .05 level among the experimental conditons. Also, no significant differences were found comparing a condition in Part A with its respective conditio...

Effect of Practice on True Score and Intra-Individual Variability for Reaction and Movement Times for Simple and Complex Movements

Abstract The effect of practice on individual differences and intra-individual variability in reaction and movement times were studied for simple and complex, discrete, motor tasks. Changes with practice for intertrial correlations of adjacent trials and the effects of an increasing number of interpolated trials on intertrial correlations were also observed. For both tasks and for both reaction and movement times, the intra-individual variability decreased with practice. The true score variability for reaction time on both tasks and for movement time on the simple task shows little change with practice. On the complex task, true score variability for movement time decreases with practice. For movement time, adjacent trial correlations increase during the early practice trials then remain stable. For reaction time adjacent trial correlations increase throughout practice. Remoteness effects on intertrial correlations were found for both movement and reaction times for both tasks.

Influence of an interpolated non-related motor task on short- and long-term memory learning and retention of a gross motor skill.

A control group of young men (N = 28) continuously practiced climbing a free-standing ladder for 20 1-min. “trials” separated by 1-min. rests; after a 1-wk. layoff they practiced 5 additional trials. The learning trend, of the exponential form, y = c − a1e−k1s − a2e−k2s was not affected by the layoff. Another group (N = 28) performed the skill in the same manner, except that prior to the layoff the 1-min. rests were replaced with practice on the pursuit rotor task. This caused a cumulative learning deficit and forgetting during the layoff. Progressive improvement in 5 post-layoff trials (without the rotor) established relearning and overcame the deficit. These effects were statistically significant. They were thought to be caused by the rotor practice interfering with just-learned ladder skill consolidation, so that the gain in skill was not processed into long-term memory.

Reliability of Constant Error and Within-Individual Variability for Kinesthetically Monitored Force Reproduction

Abstract Sixty college women volunteers performed on each of two days 8 trials of a kinesthetically monitored force reproduction task. The amount of movement of the handle of the apparatus during performance was minimal to avoid contamination of judgment with extent of movement. The reliability of constant error and within-individual variability, the latter a measure of kinesthetic sensitivity, was studied both within and between days. Within-day reliability of constant error was moderate (ranged from .66 to .86). Between-day reliability was .73 using all 8 trials for each day and ranged from .49 to .70 using blocks of four trials. Reliability of within-individual variability was low. Between-days using 8 trials for each day was .37. Using blocks of 4 trials the reliabilities ranged from .05 to .45.

RECIPROCAL INTERFERENCE IN LEARNING TWO INTERLEAVED GROSS MOTOR TASKS

When 1-min. practice trials alternate between two unrelated motor tasks so that total practice is continuous, each task interferes with the learning of the other (n = 28 males). Comparison with control group data (n = 28 males) for each task (practice on the other task being replaced with intertrial rests) shows that interference from the more complex and demanding of the two tasks occurs much earlier (compared with onset of interference from the other) and progresses through a period of cumulating effect which is followed by a period of relatively constant learning deficit.