Intertrial correlations

A more complex correlations procedure involves correlating all the practice trials with each other. This approach provides

Table 13.1 the intetrial correlation matrix from performance on a rhymic arm movement task reported by thomas and halliwell (the correlations are based on the spatial eror scores from the task.)

Information about the relationship between the performance scores of any to trials. The common finding from this analysis has been that trials that are close to each other in time are more highly corelated than trials that are frather from each other. This between-trials relationship follows what has been called a `superdiagonal from. This tern describes the way the trial-to-trial correlations appear on a correlations matrix that compares all trials againts each other with te same trials located on both the vertical and the horizontal axes of the matrix. The correlations of a trial with the trial that succeds it, such as that of trial 2 with trial 3, is found just above the diagonal of the matrix, where a trial would be correlated with iteself. On the basis of the prefix super to mean above, a superdiagonal form occurs when the highhest correlation in the matrix are along the diagonal that is just above the main diagonal of the matrix. An excellent example of this approach is in one of the few motor skill studies to apply this approach. In an experiment by thomas and halliwell (1976), participant learned three motor skills: the rotary pursuit task, the stabilitometer task and a rhytmic arm movement task. The corralation matrix in table 13.1 presents the results of participants inttial fifteen trials side of the body to a visual target in the time with a metronome. Both spatial and temporal eror constituted the performance score. As you can see in the table, the highest between-trial correlations are typically along the diagonal lacated just above the man diagonal of the correlation matrix. As you can see by looking to your right to compare a particular trial to other trials, the correlation between trials farther away is generally lower. For examplle, the correlation between trials 4 and 5 is 0,73, wheareas the corralation between trials 4 and 12 drops to 0.15. thus, these result provider additional evidence that performance early in partice is a poor predictor of performance later in pratice.

The relationship between motor abilities and the stages of learning

The third approach to investigating the relationship between performance achivement early and later in learning is to compare the motor abilities that acount for performance achievement at each stage.although controversy exists concerning whether the abilities associated with performance remain constant or change during skill learning, the prevailing view is that abilities required to performance remain constand or change during skill learning, the prevailing view is that abilities required to perform a skill can change as the person becoms more proficent at performing the skill. This means that the abilities related to performing the skill in the early stage of learning may not be the same as those related to performance in later stages. When considered in terms of how poorly we can predict performance between early and later stages of learning, this view provides a basis for accounting for this poor prediction.

ackerman (1988, 1992) provider insight into these change when he proposed a model broadly describing the relationship between the types of abilities that are primarily responsible for performance in each of the fits and posner model (discuassed in chapter 12) figure 13.2 presents a graphic representation of this relationship. In the cognitive stage of learning, in which the learner must acquire knowledge about task goal, rules, and strategies,general cognitive and broad-content abilities predominate to account for performance. General cognitive abilities include reasoning, problem solving and verbal abilities, among other; broad-content abilities include spatial orientation, atetntion control.

As the person progresses to the associative stage, perceptual speed ability becoms more predominant in acounting for performance. This includes the facility to solve problems related to visual search and memory use. Finally in the autonomous phase, the demand on perceptual and motor abilities increases so that

Ability structure

General cognitive and broad-content abilities

Perceptual speed ability

Perceptual and motor abilities

stage of skill learning

cognitive phase

assoclatieve phase

autonomous phase

figure 13.2

they become the abilities that are most highly corelated with performance.

Ackermam (1992) cites several examples of experiments that provider support for his model. In addition, he associates the relationship between the types of abilities that account for permonce and the three learning stages. He indicates that the simple relationship between abilities and learning stage show in figure 13.2 may relete only to skills in which motor performance requirements of the task are critical for task performnce and the information processing requirements of the task are critical for task performance and the information processing requirement do not change in various contexts in which the skill is performed. Altough ackermen does not use motor skill classification terminology. His description of thase types of tasks would be most closely related to those classified in chapter 1 as closed motor skills in which regulatory conditions do not change from trial to trial. In contrast for skil where information processing demands change from one situasion to anoter, the three types of abilities do not change in thier relationship to performance at each stage of learning ackerman presented evidence basad on the learning of an air traffic controller task as an example of this type of skill.

The Ackirman model must be viewed as general description of three broad categories of humam abilities and their relationship to skill performance at various stage of learning. Un fortunately, we do not know enough about the task specifity aspect of the model to relate it to specific sport skills or skils of daily living. We must wait for additional research to provide this information. However. because the progressen presented in the model depicited in figure 13.2 is in general agreement with other views (e. G., fleishman & mumfrod, 1989) about the chage of the abilities- performance relationship

during skill acquisition. We can view this model as a key component of the explanation for poor early to later learning stage performance for most complexs motor skills.

The key poin is that it is very difficult to predict futere achiement in learning a motor skill when bas the prediction on early performance only, abilities that account for a person’s level of performance change in importance as the person moves from the early stage of learning to later stages. those abiities that are importand later in accounting for a person’s performance score early in practice. Howover, prediction of future performance improves if the techer, coach or therapist is aware of both the specific abilities that are esential to performance in the different stage of learning. And also the corresponding abilities within the learner.