The relationship between task difficulty and motor performance complexity

Difficult tasks are commonly equated with complex tasks across many behaviors. Motor task difficulty is traditionally defined via Fitts’ law, using evaluation criteria based on spatial movement constraints. Complexity of data is typically evaluated using non-linear computational approaches. In this project, we investigate the potential to evaluate task difficulty via behavioral (motor performance) complexity in a Fitts-type task. Use of non-linear approaches allows for inclusion of many features of motor actions that are not currently included in the Fitts-type paradigm. Our results indicate that tasks defined as more difficult (using Fitts movement IDs) are not associated with complex motor behaviors; rather, an inverse relationship exists between these two concepts. Use of non-linear techniques allowed for the detection of behavioral differences in motor performance over the entire action trajectory in the presence of action errors and among neutrally co-constrained effectors not detected using traditional Fitts’-type analyses utilizing movement time measures. Our findings indicate that task difficulty may potentially be inferred using non-linear measures, particularly in ecological situations that do not obey the Fitts-type testing paradigm. While we are optimistic regarding these initial findings, further work is needed to assess the full potential of the approach.     

Effects of two retention interval components on performance differences between study-test and anticipation methods in paired-associate learning

Given that the retention interval consists of two qualitatively different and operationally distinguishable components, both separate and joint effects of them were necessary to assess their relative dominance in controlling both significant and nonsignificant performance differences between anticipation and study (reinforcement)-test methods; thus illuminating results thought inconsistent for about two decades. Three paired-associate learning experiments, with a total of 167 university students, were conducted with both massed (no intercycle or Type I interval) and spaced (30 sec Type 1 intervals) practice within each experiment. Both significantly and nonsignificantly superior performance resulted for the study-test method vis-à-vis the anticipation method with massed practice without practice. Findings support the retention interval hypothesis (Izawa, 1972) which is further strengthened when augmented with the capacity to account for the absolute performance differences between methods.     

On the relationship between task performance and associated verbalizable knowledge

Three experiments explore the relationship between performance on a cognitive task and the explicit or reportable knowledge associated with that performance (assessed here by written post-task questionnaire). They examine how this relationship is affected by task experience, verbal instruction and concurrent verbalization. It is shown that practice significantly improves ability to control semi-complex computer-implemented systems but has no effect on the ability to answer related questions. In contrast, verbal instruction significantly improves ability to answer questions but has no effect on control performance. Verbal instruction combined with concurrent verbalization does lead to a significant improvement in control scores. Verbalization alone, however, has no effect on task performance or question answering.     

The relationship between initial errorless learning conditions and subsequent performance

This experiment explores a suggestion by [Maxwell, J.P., Masters, R.S.W., Kerr, E., Weedon, E. (2001). The implicit benefit of learning without errors. Quarterly Journal of Experimental Psychology A 54, 1049-1068] that an initial bout of implicit motor learning confers beneficial performance characteristics, such as robustness under secondary task loading, despite subsequent explicit learning. Participants acquired a complex motor skill (golf putting) over 400 trials. The environment was constrained early in learning to minimize performance error. It was predicted that in the absence of explicit instruction, reducing error would prevent hypothesis testing strategies and the concomitant accrual of declarative (explicit) knowledge, thereby reducing dependence on working memory resources. The effect of an additional cognitive task on putting performance was used to assess reliance on working memory. Putting performance of participants in the Implicit-Explicit condition was unaffected by the additional cognitive load, whereas the performance of Explicit participants deteriorated. The relationship between error correction and episodic verbal reports suggested that the explicit group were involved in more hypothesis testing behaviours than the Implicit-Explicit group early in learning. It was concluded that a constrained, uninstructed, environment early in learning, results in procedurally based motor output unencumbered by disadvantages associated with working memory control.     

Effects of task interdependence on the relationship between helping behavior and group performance

The authors examine whether task interdependence moderates the relationship between the helping form of organizational citizenship behavior (OCB) and group performance. In a laboratory study, 62 groups with 3 members each completed a card-sequencing activity in which the level of task interdependence among group members was manipulated. Independent evaluators assessed helping by viewing videotapes of the groups' interactions during the sequencing activities. Performance was measured as a combined function of group speed and accuracy. Two prior field studies reported contradictory results regarding the impact of helping on group performance. Results from this study suggest that task interdependence may explain these results, and that the relationship between helping and group performance depends on the level of task interdependence required of group members.     

Fixed-interval performance: The dynamics of behavior and the interval length

Postreinforcement pauses from successive intervals under various fixed-interval schedules (ranging from 15 seconds to 480 seconds in length) were subjected to lag-1 autocorrelation analysis. Results from both rats and pigeons suggested that there was a consistent tendency for pause values in successive intervals to be weakly positively related. This tendency did not appear to change systematically with interval length and was exhibited both when the reinforcer magnitude was constant and when it was variable at different interval values. The findings do not support suggestions that the dynamic properties of performance under fixed-interval schedules vary systematically with interval length, and are in the opposite direction from some previous findings suggesting that measures of behavior (such as post-reinforcement pause length or number of responses) in successive intervals are inversely related.     

Strategic capacity sharing between two tasks: evidence from tasks with the same and with different task sets

The goal of the present study was to investigate the costs and benefits of different degrees of strategic parallel processing between two tasks. In a series of experiments with the dual-task flanker paradigm, participants were either instructed to process the tasks serially or in parallel, or—in a control condition—they received no specific instruction. Results showed that the participants were able to adjust the degree of parallel processing as instructed in a flexible manner. Parallel processing of the two tasks repeatedly led to large costs in performance and to high crosstalk effects compared to more serial processing. In spite of the costs, a moderate degree of parallel processing was preferred in the condition with no specific instruction. This pattern of results was observed if the same task set was used for the two tasks, but also if different ones were applied. Furthermore, a modified version of the central capacity sharing (CCS) model (Tombu and Jolicoeur in J Exp Psychol Hum Percept Perform 29:3–18, 2003) was proposed that accounts also for crosstalk effects in dual tasks. The modified CCS model was then evaluated by fitting it successfully to the present data.

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Length of the postfeedback interval and learning of probabilistic inference tasks

Learning of negative linear and J-shaped cue-criterion relations in single-cue learning tasks was studied in an experiment which varied the length of the postfeedback interval. Contrary to the predictions from a hypothesis construction model assuming that subjects construct hypotheses from the data provided by the task, there was no effect of the postfeedback interval. The results were interpreted to mean that the subjects' constructions are based on elements stored in memory, rather than on data from the task.     

The influence of task variation and maintenance tasks on the learning and affect of autistic children

Analyses of autistic children's learning and affect have begun to consider the role of antecedent variables, including the manner with which tasks are sequenced within instructional sessions. Within the context of a simultaneous-treatments design, this experiment evaluated autistic children's affect and rate of task acquisition under three experimental conditions. The conditions were (1) a constant task condition in which only one acquisition task was presented per session; (2) a varied-acquisition-task condition, in which 10 acquisition tasks were randomly interspersed throughout each session; and (3) a varied-with-maintenance-task condition, which randomly interspersed 5 acquisition tasks and 5 which had been previously acquired. The results showed significantly more efficient learning under the varied-maintenance condition, with no consistent differences separating the other two conditions. In addition, observers' ratings of the children's affect showed that the most positive judgments were produced by the varied-maintenance condition. The varied-acquisition condition was next while the constant task condition always produced the least favorable ratings. These findings are discussed in relation to the literature on massed versus distributed practice, stimulus variation, and success-induced motivation. The implications for upgrading the treatment and education of handicapped children are also reviewed.     

Feedback-seeking culture moderates the relationship between positive feedback and task performance

Current Psychology - Research exploring feedback in the form of workplace performance appraisals or in educational contexts, is common. However, there is a dearth of research to inform...     

The relationship between personality, approach to learning and academic performance

This study considers the relationship between students' approaches to learning, as measured by a short-form of Entwistle and Tait's (1995) Revised Approaches to Studying Inventory (RASI), the Big Five personality factors, as measured by Cattell's 16PFi, and the background variables of age, gender and prior educational achievement and academic performance. Subjects were 146 social science undergraduate students at a university in Scotland. Structural equation modelling identifies the Big Five personality factor scores account for between 22.7% and 43.6% of the variance across scores on the three approach to learning dimensions. Four of the Big Five personality factors and the three approach to learning dimensions were found to be poor predictors of academic performance. A linear regression analysis with academic performance as the dependent variable and age, prior educational attainment and conscientiousness as independent variables, accounted for 24.1% of the variance in performance. Our investigation suggests approach to learning is a subset of personality. However, we conclude it makes sense to measure these two groups of variables separately in educational settings.     

Effects of information-presentation mode and task complexity on the learning of probabilistic inference tasks

Learning of two-cue probabilistic inference tasks was studied in a 2 level of information-presentation mode (visual access to an ordered array of cue values vs. no such access) by 2 levels of task complexity (linear vs. nonlinear cue-criterion relations). The results replicated earlier findings in that performance was better in the linear tasks than in the nonlinear ones, and also showed that visual access to an ordered array of cue values facilitated performance, viz. there were no interactions. The results were interpreted as evidence that at least part of the suboptimal performance in ordinary experiments of this kind is due to cognitive strain introduced by the lack of control of the sequence of instances of cue-criterion pairs.     

An investigation of the relationship between trait emotional intelligence and emotional task performance

This study examined the relationships between trait emotional intelligence (EI) and tasks involving the recognition of facial expressions of emotion. Two facial expression recognition tasks using the inspection time (IT) paradigm assessed speed of emotional information processing. An unspeeded emotion recognition task was also included, and a symbol IT task was used to assess speed of processing of non-emotional information. It was found that scores on all three emotion-related tasks were strongly intercorrelated, as were scores on the three IT tasks. The two emotional IT scores remained significantly correlated when symbol IT performance was partialled out. This finding, together with the associations between the speeded (IT) and unspeeded face tasks suggests that the association between the emotional IT tasks is not entirely accounted for by general processing speed, and that a general emotion-processing ability also contributes to performance on these tasks. An EI subscale assessing Appraisal of Emotions was significantly correlated with performance on the emotional IT tasks, suggesting that self-reports of emotional perception ability do relate to performance measures.     

Retention interval and intertrial interval in a serial learning or delayed discrimination task

In each of four experiments, rats were provided with the same three-event decreasing series (18-1-0) of 0.045-g food pellets in a runway. Tracking, running fast to 18 pellets and running slow to 1 and 0 pellets, was investigated as a function of the temporal interval elapsing between the events of the series (the retention interval), shifts in retention interval, and number of trials each day (or the intertrial interval), a trial being defined as presentation of each of the three events of the series. Neither retention interval, which varied from 15 s to 30 min in various investigations, nor shifts in retention interval affected tracking when only one trial was given each day. But when more than one daily trial was given, tracking was acquired more slowly and was disrupted by a shift in retention interval from 15 s to 5 min. Tracking was also disrupted by a shift from one to two trials each day. These results indicate that when given one 18-1-0 trial each day, the rat partitions events on a first-event/subsequent-event basis; that little forgetting occurs even at long retention intervals; that somewhat different memories signal events when one or more than one 18-1-0 trial occurs each day; and that retention interval deficits can arise owing to the same or similar memories' signaling different events. The results described limit the generality of three hypotheses suggested in two recent investigations: that as retention interval increases, rats find it increasingly difficult to remember and utilize serial position cues; that tracking in serial tasks is not influenced by number of trials each day; and that there are specific stimuli associated with each retention interval which, when changed, necessarily disrupt performance.     

Motivational determinants of motor performance: The hidden second task

Summary The present study was designed to test facilitating and debilitating effects of motivational processes on motor behavior. It was predicted that motivational processes have a more pronounced effect on motor performance when control is frequently transferred to attentional mechanisms (i. e., early in the acquisition phase). The results were consistent with this expectation. A strong motive to achieve success and pretreatment designed to enhance achievement motivation were associated with an increase in the quality of performance. A strong tendency to engage in state-oriented cognitive activities, by contrast, (e.g., thinking about the potential threat to one's selfesteem resulting from failure) was associated with poorer performance, It is concluded that experiments on motor behavior in which subjects are instructed to perform a single motor task may actually involve dual-task (or even multiple-task) performance if some part of the subjects' attentional capacity is used for task-irrelevant cognitive activities.     

Human performance on an analogue of an interval bisection task

Two experiments used normal adult human subjects in an analogue of a time interval bisection task frequently used with animals. All presented durations were defined by the time between two very brief clicks, and all durations were less than 1 sec, to avoid complications arising from chronometric counting. In Experiment 1 different groups of subjects received standard durations of either 0.2 and 0.8 or 0.1 and 0.9 sec and then classified a range of durations including these values in terms of their similarity to the standard short (0.2- or 0.1-sec) and long (0.8- or 0.9-sec) durations. The bisection point (defined as the duration classified as "long" on 50% of trials) was located at 0.43 sec in the 0.2-0.8 group, and at 0.46 sec in the 0.1-0.9 group. Experiment 2 replicated Experiment 1 using a within-subject procedure. The bisection point of both 0.2- and 0.8 sec and 0.1- and 0.9-sec durations was found to be 0.44 sec. Both experiments thus found the bisection point to be located at a duration just lower than the arithmetic mean of the standard short and long durations, rather than at the geometric mean, as in animal experiments. Some other performance measures, such as difference limen, and Weber ratio, were, however, of similar values to those found in bisection tasks with animals. A theoretical model assuming that humans bisect by taking the difference between a presented duration and the short and long standards, as well as having a bias to respond "long", fitted the data well. The model incorporated scalar representations of standard durations and thus illustrated a way in which the obtained results, although different from those found with animal subjects, could be reconciled with scalar timing theory.     

The effect of training and handedness on the performance of two simple motor tasks

In the first experimental series nine right-handed and nine left-handed subjects were tested on each side on two tasks. The first task measured the accuracy of reproduction of pressure in attempted extension of the elbow joint, and the second the speed of oscillation of attempted flexion and extension of the elbow joint. The results showed no significant difference in performance on the two sides in the accuracy task but a significant difference in performance on the speed task.

In the second experimental series the effect of 15-minutes daily training on each of two tasks over a four-week period was investigated on six subjects. The two tasks were the same as those used in the first experimental series, and attempted movement at the metacarpo-phalangeal joint as well as the elbow joint was studied. The mean results of all subjects showed a significant reduction in the mean error of the “accuracy” task over the training period for both the finger and arm. However, further analysis suggests that this may have been due to a clarifying of the subjects' concept of the target value rather than an improvement in his ability to grade the appropriate muscle contractions. A significant increase in the mean speed of oscillation over the training period was also recorded for both finger and arm. This improvement was accompanied in most instances by a corresponding decrease in variation of cycle length of the individual oscillations, which is interpreted as an improvement in the subjects' “timing” of the appropriate muscle contractions.     

The impact of stimulus-specific practice and task instructions on response congruency effects between tasks

In task switching experiments participants have to respond to the same set of stimuli while task instructions vary (e.g., digit stimuli are assigned to left- or right-sided key presses by means of magnitude vs. parity classification). Response congruency effects denote worse performance for a stimulus, which is associated with different responses in the two tasks as compared to a stimulus, which is associated with the same response. Previous research suggests that such effects reflect direct links between stimuli and responses acquired in the course of experimental practice. In the current study we investigated the impact of stimulus-specific practice and task instruction by reversing the S–R mapping of one task (Experiment 1) or replacing one task with a new one (Experiment 2) in the second half of an experimental session. Consistent with the direct link account, S–R links practiced during the first half of the experiment largely determined congruency effects despite altered task instructions. Furthermore, the results suggest that previously practiced S–R links (a) can be relatively quickly overwritten by practicing a novel S–R mapping, and (b) are subject to passive decay when no longer in use.     

Information processing abilities and performance on two perceptual-motor tasks

The purpose of this study was to investigate whether the hypothesized information-processing mechanisms, thought to be reflected by the slope and intercept of the regression of choice reaction time on stimulus information or information transmitted could account for performance on two novel laboratory tasks. In addition, analyses were performed to determine whether these theorized mechanisms represent stable within individual abilities or task specific capabilities. Analysis indicated that the slopes obtained from two different choice reaction time paradigms were unrelated while intercepts were moderately correlated. Examination of the pattern of zero-order correlations further showed that regression components were not meaningfully related to performance on either novel task, suggesting that knowledge of information-processing mechanisms, as assessed in choice RT paradigms, did not enhance the understanding of performance in more complex tasks.