Effect Of Secondary Task Research Articles

Task integration as a factor in secondary-task effects on sequence learning

In several studies it has been found that implicit sequence learning is impaired by the concurrent performance of a secondary task. In most studies the task was to count high-pitched tones when high-pitched and low-pitched tones were presented in a random sequence. In this paper the hypothesis is examined that dual-task interference in the particular combination of tasks results from task integration, in particular from the learning of an integrated visual-auditory sequence in which every second (auditory) element is random. Instead of the tone-counting task a similar go/no-go task was used in which foot responses to high-pitched tones were performed. In Exp. 1 the sequence of tones was random in one condition, but in two other conditions repeated tone sequences of 5 and 6 elements were combined with visual sequences of 6 elements. Under dual-task test conditions, implicit learning of the visual as well as the auditory sequences was better with the auditory sequence of 6 elements than of 5 elements, while under single-task test conditions the nature of the tone sequence had no effect. In Exp. 2 the superior implicit learning with the 6-element sequence was replicated with different test procedures in which either the visual or auditory sequence was changed to random or in which the two sequences remained intact but were shifted by one element relative to each other. Randomization of the visual or auditory sequences not only impaired visual or auditory RT, respectively, but also impaired RT to stimuli in the other modality, and this cross-modal effect was almost as strong as the intra-modal effect of randomization. Finally, in Exp. 3 it was shown that integrated visual-auditory sequences are learned only when responses to both of them are required, but not when the tones can be neglected. These results are consistent with a conception of implicit learning as (at least partly) a basic and nonselective type of learning of all potentially behaviorally relevant relations between stimuli in the environment and one's own actions.

Secondary-task effects on sequence learning.

With a repeated sequence of stimuli, performance in a serial reaction-time task improves more than with a random sequence. The difference has been taken as a measure of implicit sequence learning. Implicit sequence learning is impaired when a secondary task is added to the serial RT task. In the first experiment, secondary-task effects on different types of sequences were studied to test the hypothesis that the learning of unique sequences (where each sequence element has a unique relation to the following one) is not impaired by the secondary task, while the learning of ambiguous sequences is. The sequences were random up to a certain order of sequential dependencies, where they became deterministic. Contrary to the hypothesis, secondary-task effects on the learning of unique sequences were as strong or stronger than such effects on the learning of ambiguous sequences. In the second experiment a hybrid sequence (with unique as well as ambiguous transitions) was used with different secondary tasks. A visuo-spatial and a verbal memory task did not interfere with the learning of the sequence, but interference was observed with an auditory go/no-go task in which high- and low-pitched tones were presented after each manual response and a foot pedal had to be pressed in response to high-pitched tones. Thus, interference seems to be specific to certain secondary tasks and may be related to memory processes (but most likely not to visuo-spatial and verbal memory) or to the organizations of sequences, consistent with previous suggestions.

‘Pseudoautomatization’ in manual control: a simulation study

Within the framework of models of central capacity, automatization (as indicated by decreasing dual-task interference over the course of practice) can be attributed to a change of the performance-resource function, such that performance becomes better for a given amount of capacity, and performance decrements become smaller for a given reduction in capacity. In general, automization is considered as a change in human information processing that makes it less susceptible to disturbances by secondary tasks. By way of simulation it is demonstrated that in user-machine systems ‘pseudoautomatization’ can occur. This is a decline of dual-task interference without any alteration of the secondary-task effects on human information processing such as are thought to underlie automatization. Pseudoautomatization is discussed as a potential fallacy in interpreting system-performance measures and as a means by which human operators potentially immunize user-machine systems against disturbances of human information proc...

Effects of secondary tasks on search performance.

Two experiments studied the effect of secondary task load on continuous visual search. Two effects were observed when a secondary task was applied. Search speed (which is assumed to reflect the efficiency of nontarget rejection) was impaired, whereas target detection distance (which presumably reflects the efficiency of target detection) increased. These findings are explained in the framework of a two-process model of visual search which assumes that two operations are performed simultaneously during each fixation, that is, automatic detection and controlled search. The secondary task interferes with the operation of controlled search which reacts to this impairment by way of a compensatory slow-down of search speed. This gain in time also benefits the operation of automatic detection which converts the temporal gain into a spatial extension of the area under its control.

On adaptive characteristics of human operator in control task

By means of spectral analysis, the adaptive characteristics of human operators in simple pursuit control task was examined. The frequency responses of human operators were fairly dependent on controlled elements and handling devices which was used. As the controlled element lag increased, more effective phase-lead equalizations were caused in the operators' responses. However, because of their inherent time delay, nobody could realize the positive phase shift and system performances were gradually deteriorated. For the second order oscillatory element, the subjects couldn't inhibit their oscillatory behaviors sufficiently.It was also attempted the examine the effect of secondary task to the control task by adding a visual detectio-n task the subjects. The average system error was slightly increased than that of the ease without the secondary task.

Secondary task effects on serial verbal learning.

Secondary task effects on serial verbal learning.

The organization of skilled response

A series of experiments concerned with the ways in which responses become organized is discussed. The principle parameter in most studies was stimulus coherence, and tracking tasks were used as a vehicle because graded responses permit detailed and fine-grained analyses. Both spatial and temporal coherence are used in response organization, and type of response strategy varys with degree of stimulus coherence. The effects of secondary tasks, sequence length and task coding were also examined.