Attentional Overload,stress, and simulate Driving Performance

This study tests the hypothesis that driver stress is associated with performance impairment because stress-prone drivers are vulnerable to overload of attentional resources. Eighty young-adult subjects performed a simulated drive concurrently with a grammatical reasoning task, presented either visually or auditorily. Priority assigned to the 2 tasks was also manipulated. In general, the patterns of dual-task interference predicted by attentional resource theory were not found, although interference was apparent with the auditory reasoning task. Measures of vulnerability to driver stress and intrusive cognitions were related to impaired lateral control mainly when task demands were relatively low, contrary to the overload hypothesis. These data indicate that performance in this task paradigm is characterized by adaptive mobilization of effort to meet changing task demands. Stressed drivers adapted to high levels of demand fairly efficiently, but they may be at risk of performance impairment when the task requires relatively little active control. Advantages and disadvantages of the simulator approach are discussed.     

The Structural Constraints and Strategic Control of Resource Allocation

Time-sharing performance was evaluated as a function of the structural configurations of the time-shared tasks and strategic resource-allocation training. A secondary task technique was employed with five task pairs that varied in their structural similarity. The primary task difficulty was time-varying within a trial. Consistent with a common finding in the literature, the global performance measures showed that the degree of task interference increased as the degree of shared resources between the time-shared tasks increased. The moment-by-moment performance, however, revealed that small task interference did not necessarily indicate that the primary task performance was consistently protected against the time-varying difficulty changes. Subjects' failure in protecting the primary task performance was attributed to two possible causes: a skill limitation in the control of resource allocation and a structural limitation inherent in the dual task configuration. This distinction was reinforced by the finding that the strategy training was successful in improving resource allocation for the structurally identical task pair only. Our data demonstrated the role of multiple resource concepts in predicting time-sharing performance in a dynamic environment.     

Determinants of task performance and invested effort: a need for closure by relative cognitive capacity interaction analysis

This study examines the simultaneous effects of need for closure (NFC) and relative cognitive capacity on invested effort and task performance within the integrative analysis framework using behavioral data. Two main results were obtained. First, the authors revealed a significant interaction effect between relative cognitive capacity (manipulated through task difficulty) and NFC (manipulated through time pressure, noise, and fear of invalidity as well as assessed by an individual differences measure) on effort investment. Second, contrary to dispositional NFC, manipulations yielded a "dual effect" because they negatively affected task performance as well as invested effort. The latter result was interpreted as an indication that noise and time pressure manipulations also tax cognitive resources. The two main findings are discussed and the authors go further into the divergences between dispositional and manipulated NFC.     

Cognitive Load in Cross‐Modal Dual‐Task Processing

Unitary‐resource models posit a collective attentional resource responsible for sustaining information processing across all modalities. In contrast, multiple‐resource models presume a system of modality‐independent resources. The two models predict similar within‐modal performance, but seemingly contradictory cross‐modal performance. Discordant outcomes in past research are here hypothesized to result from inconsistent levels of cognitive load imposed within experimental tasks. Participants monitored two simultaneously presented alphabetic letter arrays consisting of the serial presentation of a target and multiple distractors. The dual‐task design required the identification of targets in within‐modal and cross‐modal trials. Cognitive load was manipulated by altering the presentation rate of the letters. While cross‐modal performance was generally superior and cognitive load was associated with decreasing performance, the cross‐modal advantage prominent at low levels of cognitive load was absent under high cognitive load. Therefore, neither resource model can alone account for dual‐task processing, suggesting the role of a hierarchical resource model. Copyright © 2015 John Wiley & Sons, Ltd.     

A dynamic,self-regulatory model of affect and performance: Interactions between states,traits and task demands

State–trait consistency and valence principles were integrated within a dynamic self-regulatory framework to predict interactive effects of state affect, trait affect and task demands on performance. State affect and performance were measured repeatedly as individuals completed a complex and dynamic decision-making task. Task demands were manipulated at the within-person level. The beneficial effect of state positive affect was strongest for individuals with high trait positive affect; however this effect was only evident under high task demands. The detrimental effect of state negative affect was weakest for individuals with high trait negative affect, with this effect being constant across task demand levels. This study demonstrated that state–trait inconsistency can be bad for individuals with high trait positive affect and consistency can be good for individuals with high trait negative affect.     

Attention and memory protection: Interactions between retrospective attention cueing and interference

Visual working memory (VWM) and attention have a number of features in common, but despite extensive research it is still unclear how the two interact. Can focused attention improve VWM precision? Can it protect VWM from interference? Here we used a partial-report, continuous-response orientation memory task to examine how attention and interference affect different aspects of VWM and how they interact with one another. Both attention and interference were orthogonally manipulated during the retention interval. Attention was manipulated by presenting informative retro-cues, whereas interference was manipulated by introducing a secondary interfering task. Mixture-model analyses revealed that retro-cues, compared to uninformative cues, improved all aspects of performance: Attention increased recall precision and decreased guessing rate and swap-errors (reporting a wrong item in memory). Similarly, performing a secondary task impaired all aspects of the VWM task. In particular, an interaction between retro-cue and secondary task interference was found primarily for swap-errors. Together these results suggest that both the quantity and quality of VWM representations are sensitive to attention cueing and interference modulations, and they highlight the role of attention in protecting the feature–location associations needed to access the correct items in memory.     

Prospective Memory and Divided Attention

In three experiments, we manipulated the processing demands of a concurrent task to test the hypothesis that an event-based prospective memory task satisfies a criterion of automaticity proposed by Hasher and Zacks (1979). As in the previous studies, a prospective memory task (pressing a key whenever a target word was presented) was embedded within a short-term memory task (remembering seven words). In addition, participants performed a concurrent memory task which varied in difficulty. Participants repeated either 0 to 6 randomly generated digits or a single word. In all three experiments, short-term memory performance was influenced by the concurrent memory load. Prospective performance, in contrast, was not affected by the memory load even though an attempt was made to increase the difficulty of the prospective task by manipulating the specificity of the target instructions (Experiment 2) and the number of target words (Experiments 2 and 3). The results are discussed within the framework of automatic processing.     

Effects of resource availability and importance of behavior on the experience of crowding.

According to the interference formulation, participants in a crowded setting will experience interference to the extent that behavioral goals conflict with environmental conditions. The importance of the behavioral goals directly affects not only the magnitude of the interference but also the mechanism by which people cope with interference. It was reasoned that important goals would induce a more active coping strategy in a crowded setting than in an uncrowded setting and would maintain task performance at the price of increasing crowding stress. When the behavioral goal is unimportant, decrements in task performance preclude a rise in stress. A laboratory study manipulated group size, in order to vary the availability of resources, and the importance of the task behavior. The predictions were confirmed, and partial confirmation was obtained for predictions involving the effects of the internal-external personality dimension. The meaning of the results is discussed in terms of other findings in the literature on crowding and the mediating role of the type of mechanism used to cope with interference.     

Selective reaching: evidence for multiple frames of reference

Students participated in 3 experiments investigating the use of environment- and action-centered reference frames in selective reaching. They pointed to a green target appearing either with or without a red distractor. Target-distractor distance was manipulated, and distractor interference (difference between distractor trials and no-distractor trials) was measured in reaction time, movement time, and movement endpoint. Target-distractor distance determined the dominant frame of reference. Small distances evoked an environment-centered framework that encoded targets within an external context. Large distances evoked an action-centered framework that encoded targets relative to the start position of the hand. Results support the hypothesis that the brain represents spatial information in multiple frames of reference, with the dominant frame of reference being dependent on the task demands.     

提取干扰对内隐记忆的影响

以往研究多认同内隐记忆不会受到干扰的影响,但主要集中于编码时的干扰不会影响随后的内隐记忆提取成绩,而对于提取时的干扰是否也不会影响内隐记忆成绩仍存在疑义。该文在实验1采用学习-测验范式,通过在提取阶段设置同时干扰任务进一步考察提取干扰与内隐记忆的关系,结果表明提取干扰下并未发现明显的启动效应,即提取干扰破坏了内隐记忆。为进一步探讨内隐记忆的提取干扰效应是否源于记忆与干扰刺激同时呈现所引起的知觉表征竞争,实验2改变了记忆与干扰刺激的呈现顺序,结果表明不论干扰刺激在记忆项目之前或之后呈现,启动效应均受到影响。相比之下,提取干扰对再认成绩的影响并不明显(实验3)。上述结果表明,内隐记忆的提取干扰效应是源于一般认知资源的竞争,在提取过程中任何能够产生认知资源竞争的变量设置都可能会削减内隐测验中的启动效应。     

An analysis of memory-based theories of automaticity

Memory-based theories of automaticity predict that performance in a memory search task which is automatic will not require a representation of the memory set in working memory. The information contained in working memory was manipulated by inserting an interference task between the presentation of a memory set and a probe stimulus in a memory search task. The interference task prevented rehearsal, necessitating the retrieval of the memory set from long-term memory in variably mapped (VM) conditions. Performance in consistently mapped (CM) conditions provided strong support for memory-based theories of automaticity. With CM practice, both the effects of memory load and the effect of the interference task were eliminated. Furthermore, there was a temporal coupling in the reduction of these two effects with consistent practice. Monte Carlo simulations of memory-based automaticity predict such a temporal coupling. Automaticity is viewed as a continuum reflecting the relative contribution of the direct memory access of past solutions from long-term memory on performance.     

Eye movements and a dynamic stimulus situation

Two experiments were conducted to investigate performance with and without voluntary eye movements in a dynamic stimulus situation. Experiment I used a combined tracking and prediction task. Level of training, complexity of the signal, and visual region sampled were the variables of interest. Experiment II manipulated the same variables in only the prediction task. Thus, the amount of attention allotted to the prediction task was varied between experiments. The d' measure indicated that under peripheral vision instructions accuracy on the prediction task was the same as under foveal vision instructions provided that: (1) the level of task complexity was low, (2) the subjects were well trained, and (3) only the prediction task was performed, or in the dual task situation only visual regions near the fovea were sampled. All other combinations of the variables resulted in a lower performance scores under peripheral vision instructions. Results are interpreted within the framework of current theories of the functional visual field.     

A dynamical framework to understand performance trade-offs and interference in dual tasks.

This study demonstrated that the dynamic pattern approach may reconcile resource and outcome conflict theories to explain performance in dual tasks. Participants performed a bimanual coordination task and a reaction time task with different conditions of attentional priority. Results showed a trade-off between pattern variability and reaction time when priority was given to the coordination task. Such a trade-off was indicative of resource allocation. An analysis of perturbation in the bimanual coordination revealed interference, a reputed sign of outcome conflict. Moreover, interference diminished substantially when priority was given to the bimanual task. The coexistence of performance trade-off and outcome conflict suggests that these two phenomena are not mutually exclusive. Rather, both may follow from modifying the coupling between the limbs through attention.     

The influence of temporal selection on spatial selection and distractor interference: an attentional blink study.

Both spatial and temporal selection require focused attention. The authors examine how temporal attention affects spatial selection. In a dual-task rapid serial visual presentation paradigm, temporal selection of a target (T1) impairs processing of a second target (T2) that follows T1 within 500 ms. This process is the attentional blink (AB). To test the effects of withdrawing temporal attention, the authors measured concurrent distractor interference on T2 when the distractors were presented during and outside of the AB. Perceptual interference was manipulated by the similarity in color between T2 and concurrent distractors, and response interference was manipulated by the flanker congruency task. Results showed that perceptual interference was larger during the AB. Response interference also increased during the AB, but only when perceptual interference was high. The authors conclude that temporal selection and spatial selection rely on a common attentional process.     

Interference to ongoing activities covaries with the characteristics of an event-based intention

Previous studies of event-based prospective memory have demonstrated that the character of an ongoing task can affect cue detection. By contrast, this study demonstrated that there is a reciprocal relationship insofar as cue-verification and response-retrieval processes interfered with making a response in the ongoing task. The amount of interference was determined by the type of intention, which was manipulated to affect the complexity of verification and retrospective response retrieval. These relationships were true even when the interference caused by cue detection was separated from a more general effect to ongoing-task performance caused by shifts in attentional allocation policies. The results have theoretical implications for models that attempt to specify the cognitive microstructure of event-based prospective memory.     

Challenge Point: A Framework for Conceptualizing the Effects of Various Practice Conditions in Motor Learning

The authors describe the effects of practice conditions in motor learning (e.g., contextual interference, knowledge of results) within the constraints of 2 experimental variables: skill level and task difficulty. They use a research framework to conceptualize the interaction of those variables on the basis of concepts from information theory and information processing. The fundamental idea is that motor tasks represent different challenges for performers of different abilities. The authors propose that learning is related to the information arising from performance, which should be optimized along functions relating the difficulty of the task to the skill level of the performer. Specific testable hypotheses arising from the framework are also described.     

Visuospatial and verbal memory in mental arithmetic

Working memory allows complex information to be remembered and manipulated over short periods of time. Correlations between working memory and mathematics achievement have been shown across the lifespan. However, only a few studies have examined the potentially distinct contributions of domain-specific visuospatial and verbal working memory resources in mental arithmetic computation. Here we aimed to fill this gap in a series of six experiments pairing addition and subtraction tasks with verbal and visuospatial working memory and interference tasks. In general, we found higher levels of interference between mental arithmetic and visuospatial working memory tasks than between mental arithmetic and verbal working memory tasks. Additionally, we found that interference that matched the working memory domain of the task (e.g., verbal task with verbal interference) lowered working memory performance more than mismatched interference (verbal task with visuospatial interference). Findings suggest that mental arithmetic relies on domain-specific working memory resources.     

Challenge point: a framework for conceptualizing the effects of various practice conditions in motor learning

The authors describe the effects of practice conditions in motor learning (e.g., contextual interference, knowledge of results) within the constraints of 2 experimental variables: skill level and task difficulty. They use a research framework to conceptualize the interaction of those variables on the basis of concepts from information theory and information processing. The fundamental idea is that motor tasks represent different challenges for performers of different abilities. The authors propose that learning is related to the information arising from performance, which should be optimized along functions relating the difficulty of the task to the skill level of the performer. Specific testable hypotheses arising from the framework are also described.     

Instructional strategy effects on the retention and transfer of procedures of different difficulty level

In the present study, the effects of two instructional strategies on the retention and transfer of procedures of different difficulty level were investigated. Difficulty level was manipulated by providing a different number of cues during training. The instructional strategies differed with respect to the amount of contextual interference. Sixty-four subjects were randomly assigned to either a high interference group or a low interference group. Retention and transfer were measured immediately following training and after a three-week delay. The dependent variables were number of errors and decision time. Results showed no differences between the two training groups over the various difficulty levels. Results further showed that retention performance increased as fewer cues were available during practice. It is suggested that ‘delayed automatization’ can account for the observed increment in performance level. It is further suggested that contextual interference may produce delayed automatization of task performance but is only effective if relationships can be discovered in the learning material.     

How is performance limited: Testing the notion of central capacity

Two-dimensional pursuit tracking task was employed in three experiments designed to test three predictions of the central capacity model of performance limitations under time-sharing conditions. These are the predicted effects of change in task difficulty, task emphasis and their interaction. Each of simultaneously performed tracking dimensions (horizontal and vertical) was treated as a separate task and manipulated independently. Tracking difficulty on each dimension and their relative emphasis were jointly manipulated. When frequency or velocity of target movement served as difficulty parameters, and control complexity was relatively low, tradeoffs between dimensions in different priority conditions were small and task difficulty had no effect on the performance of the concurrent task, neither did it interact with task emphasis. When control complexity was increased and in addition was manipulated as the difficulty parameter, linear tradeoff was observed and difficulty seemed to interact with task emphasis. These results cannot be easily accommodated within a strict central capacity model. An alternative interpretation based on a multiple capacity approach is outlined.