The working memory costs of a central attentional bottleneck in multitasking

AbstractWhen two (or more) tasks, each requiring a rapid response, are performed at the same time then serial processing may occur at certain processing stages, such as the response selection. There is accumulating evidence that such serial processing involves additional control processes, such as inhibition, switching, and scheduling (termed the active scheduling account). The present study tested whether the existence of serial processing in multitasking leads to a requirement for processes that coordinate processing in this way (active scheduling account) and, furthermore, whether such control processes are linked to the executive functions (EF) of working memory (WM). To test this question, we merged the psychological refractory period (PRP) paradigm with a WM task, creating a complex WM span task. Participants were presented with a sequence of letters to remember, followed by a processing block in which they had to perform either a single task or a dual task, and finally were asked to recall the letters. Results showed that WM performance, i.e. the amount of letters recalled in the correct order, decreased when performing a dual task as compared to performing a single task during the retention interval. Two further experiments supported this finding using manipulations of the dual task difficulty. We conclude that the existence of serial processing in multitasking demands additional control processes (active scheduling) and that these processes are strongly linked to the executive functions of working memory.

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Localization of Executive Functions in Dual-Task Performance with fMRI

Journal of Cognitive Neuroscience ◽

10.1162/089892902760807195 ◽

2002 ◽

Vol 14 (8) ◽

pp. 1184-1199 ◽

Cited By ~ 209

Author(s):

André J. Szameitat ◽

Torsten Schubert ◽

Karsten Müller ◽

D. Yves von Cramon

Keyword(s):

Executive Functions ◽

Task Performance ◽

Dual Task ◽

Task Difficulty ◽

Task Condition ◽

Subtraction Method ◽

Dual Task Condition ◽

Single Task ◽

Dual Task Performance ◽

Task Conditions

We report a study that investigated the neuroanatomical correlates of executive functions in dual-task performance with functional magnetic resonance imaging. Participants performed an auditory and a visual three-choice reaction task either separately as single tasks or concurrently as dual tasks. In the dual-task condition, two stimuli were presented in rapid succession to ensure interference between the component tasks (psychological refractory period). The behavioral data showed considerable performance decrements in the dual-task compared to the single-task condition. Dual-task-related activation was detected with two different neuroimaging methods. First, we determined dual-task-related activation according to the method of cognitive subtraction. For that purpose, activation in the dual-task was compared directly with activation in the single-task conditions. This analysis revealed that cortical areas along the inferior frontal sulcus (IFS), the middle frontal gyrus (MFG), and the intraparietal sulcus (IPS) are involved in dual-task performance. The results of the subtraction method were validated with the method of parametric manipulation. For this purpose, a second dual-task condition was introduced, where the difficulty of the dual-task coordination was increased compared with the first dual-task condition. As expected, behavioral dual-task performance decreased with increased dual-task difficulty. Furthermore, the increased dual-task difficulty led to an increase of activation in those cortical regions that proved to be dual-task related with the subtraction method, that is, the IFS, the MFG, and the IPS. These results support the conclusion that dorsolateral prefrontal and superior parietal cortices are involved in the coordination of concurrent and interfering task processing.

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Locus of Backward Crosstalk Effects on Task 1 in a Psychological Refractory Period Task

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169/a000224 ◽

2014 ◽

Vol 61 (1) ◽

pp. 30-37 ◽

Cited By ~ 7

Author(s):

Yao-Ting Ko ◽

Jeff Miller

Keyword(s):

Dual Task ◽

Refractory Period ◽

Psychological Refractory Period ◽

Response Selection ◽

Stimulus Onset ◽

Standard Response ◽

Backward Crosstalk ◽

Selection Stage ◽

Prp Paradigm ◽

Response Selection Bottleneck

Our performance on a task decreases when the task is in a dual-task situation than when it is in isolation. An important experimental setting for dual-task situation is the psychological refractory period (PRP) paradigm, and the dual-task performance decrements in the PRP paradigm are referred to as PRP interference. The standard response-selection bottleneck (RSB) models state that the response-selection stage of the second task (T2) cannot start until the response-selection stage of the first task (T1) finishes, resulting in the PRP interference. Contrary to the prediction of RSB models, several researchers have found T2’s modulations on T1’s performance, and have suggested that T1’s selection-related processes are affected by T2’s selection-related processes, referred to as backward crosstalk effects. The locus of backward crosstalk effects is not clear, however, because RTs were measured in most previous studies. By using semantically unrelated stimuli and responses and by measuring T1’s lateralized readiness potential, we examined the locus of backward crosstalk effects. We found that the interval between T1’s stimulus onset and the stimulus-locked LRP onset was affected, suggesting T2’s response selection starts before T1’s selection is complete. The present result provided electrophysiological evidence focusing on T1’s changes in favor of the hypothesis of parallel response selection in the PRP paradigm.

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Acute effects of donepezil in healthy young adults underline the fractionation of executive functioning

Journal of Psychopharmacology ◽

10.1177/0269881110391832 ◽

2011 ◽

Vol 25 (11) ◽

pp. 1508-1516 ◽

Cited By ~ 16

Author(s):

GE Ginani ◽

S Tufik ◽

OFA Bueno ◽

M Pradella-Hallinan ◽

J Rusted ◽

...

Keyword(s):

Working Memory ◽

Executive Functions ◽

Task Performance ◽

Dual Task ◽

Cholinergic System ◽

Acute Effects ◽

Top Down ◽

Positive Effects ◽

Dual Task Performance ◽

Visuomotor Performance

The cholinergic system is involved in the modulation of both bottom-up and top-down attentional control. Top-down attention engages multiple executive control processes, but few studies have investigated whether all or selective elements of executive functions are modulated by the cholinergic system. To investigate the acute effects of the pro-cholinergic donepezil in young, healthy volunteers on distinct components of executive functions we conducted a double-blind, placebo-controlled, independent-groups design study including 42 young healthy male participants who were randomly assigned to one of three oral treatments: glucose (placebo), donepezil 5 mg or donepezil 7.5 mg. The test battery included measures of different executive components (shifting, updating, inhibition, dual-task performance, planning, access to long-term memory), tasks that evaluated arousal/vigilance/visuomotor performance, as well as functioning of working memory subsidiary systems. Donepezil improved sustained attention, reaction times, dual-task performance and the executive component of digit span. The positive effects in these executive tasks did not correlate with arousal/visuomotor/vigilance measures. Among the various executive domains investigated donepezil selectively increased dual-task performance in a manner that could not be ascribed to improvement in arousal/vigilance/visuomotor performance nor working memory slave systems. Other executive tasks that rely heavily on visuospatial processing may also be modulated by the cholinergic system.

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Interfering with the Central Executive by Means of a Random Interval Repetition Task

The Quarterly Journal of Experimental Psychology Section A ◽

10.1080/713755748 ◽

1998 ◽

Vol 51 (1) ◽

pp. 197-218 ◽

Cited By ~ 45

Author(s):

André Vandierendonck ◽

Gino De Vooght ◽

Koen Van der Goten

Keyword(s):

Working Memory ◽

Dual Task ◽

Memory Task ◽

Central Executive ◽

Memory Model ◽

Random Interval ◽

Single Task ◽

Task Conditions ◽

Repetition Task ◽

Working Memory Model

Four dual-task experiments are reported in which a short-term memory task is performed concurrently with a random interval repetition task, which was designed to interfere with functions normally attributed to the central executive in the working memory model of Baddeley and Hitch (1974). The task was found to interfere with supra-span serial recall and with backward memory span, but did not disrupt performance on a forward-memoryspan task. The effects were observed in dissociation with effects of articulatory suppression and matrix tapping, so that the locus of the effects of the new task is not due to the slave systems. In addition, single-task random-interval repetition performance was sampled and compared to performance in the dual-task conditions of all four experiments. Although quality of tapping performance differed between the single-task and the dual-task conditions, it was not related to recall performance. All the results are discussed with reference to the working memory model.

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Integrating the Behavioral and Neural Dynamics of Response Selection in a Dual-task Paradigm: A Dynamic Neural Field Model of Dux et al. ()

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00496 ◽

2014 ◽

Vol 26 (2) ◽

pp. 334-351 ◽

Cited By ~ 13

Author(s):

Aaron T. Buss ◽

Tim Wifall ◽

Eliot Hazeltine ◽

John P. Spencer

Keyword(s):

Cognitive Control ◽

Dual Task ◽

Hebbian Learning ◽

Response Selection ◽

Neural Model ◽

Neural Basis ◽

Single Task ◽

Neural Field Model ◽

Sensory Motor ◽

Task Trial

People are typically slower when executing two tasks than when only performing a single task. These dual-task costs are initially robust but are reduced with practice. Dux et al. ( 2009 ) explored the neural basis of dual-task costs and learning using fMRI. Inferior frontal junction (IFJ) showed a larger hemodynamic response on dual-task trials compared with single-task trial early in learning. As dual-task costs were eliminated, dual-task hemodynamics in IFJ reduced to single-task levels. Dux and colleagues concluded that the reduction of dual-task costs is accomplished through increased efficiency of information processing in IFJ. We present a dynamic field theory of response selection that addresses two questions regarding these results. First, what mechanism leads to the reduction of dual-task costs and associated changes in hemodynamics? We show that a simple Hebbian learning mechanism is able to capture the quantitative details of learning at both the behavioral and neural levels. Second, is efficiency isolated to cognitive control areas such as IFJ, or is it also evident in sensory motor areas? To investigate this, we restrict Hebbian learning to different parts of the neural model. None of the restricted learning models showed the same reductions in dual-task costs as the unrestricted learning model, suggesting that efficiency is distributed across cognitive control and sensory motor processing systems.

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Evidence of Serial Processing in Visual Word Recognition

Psychological Science ◽

10.1177/0956797617751898 ◽

2018 ◽

Vol 29 (7) ◽

pp. 1062-1071 ◽

Cited By ~ 10

Author(s):

Alex L. White ◽

John Palmer ◽

Geoffrey M. Boynton

Keyword(s):

Parallel Processing ◽

Dual Task ◽

Semantic Category ◽

The Other ◽

Task Condition ◽

Dual Task Condition ◽

Single Task ◽

Serial Processing ◽

Text Color ◽

Physical Features

To test the limits of parallel processing in vision, we investigated whether people can recognize two words at once. Participants viewed brief, masked pairs of words and were instructed in advance to judge both of the words (dual-task condition) or just one of the words (single-task condition). For judgments of semantic category, the dual-task deficit was so large that it supported all-or-none serial processing: Participants could recognize only one word and had to guess about the other. Moreover, participants were more likely to be correct about one word if they were incorrect about the other, which also supports a serial-processing model. In contrast, judgments of text color with identical stimuli were consistent with unlimited-capacity parallel processing. Thus, under these conditions, serial processing is necessary to judge the meaning of words but not their physical features. Understanding the implications of this result for natural reading will require further investigation.

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Effects of Concurrent Manual Task Performance on Connected Speech Acoustics in Individuals With Parkinson Disease

Journal of Speech Language and Hearing Research ◽

10.1044/2019_jslhr-s-msc18-18-0190 ◽

2019 ◽

Vol 62 (7) ◽

pp. 2099-2117 ◽

Cited By ~ 2

Author(s):

Jason A. Whitfield ◽

Zoe Kriegel ◽

Adam M. Fullenkamp ◽

Daryush D. Mehta

Keyword(s):

Task Performance ◽

Speech Production ◽

Dual Task ◽

Motor Task ◽

Task Condition ◽

Connected Speech ◽

Speech Acoustics ◽

Single Task ◽

Manual Task ◽

Task Conditions

Purpose Prior investigations suggest that simultaneous performance of more than 1 motor-oriented task may exacerbate speech motor deficits in individuals with Parkinson disease (PD). The purpose of the current investigation was to examine the extent to which performing a low-demand manual task affected the connected speech in individuals with and without PD. Method Individuals with PD and neurologically healthy controls performed speech tasks (reading and extemporaneous speech tasks) and an oscillatory manual task (a counterclockwise circle-drawing task) in isolation (single-task condition) and concurrently (dual-task condition). Results Relative to speech task performance, no changes in speech acoustics were observed for either group when the low-demand motor task was performed with the concurrent reading tasks. Speakers with PD exhibited a significant decrease in pause duration between the single-task (speech only) and dual-task conditions for the extemporaneous speech task, whereas control participants did not exhibit changes in any speech production variable between the single- and dual-task conditions. Conclusions Overall, there were little to no changes in speech production when a low-demand oscillatory motor task was performed with concurrent reading. For the extemporaneous task, however, individuals with PD exhibited significant changes when the speech and manual tasks were performed concurrently, a pattern that was not observed for control speakers. Supplemental Material https://doi.org/10.23641/asha.8637008

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Time-Based Measures of Monitoring in Association With Executive Functions in Kindergarten Children

Zeitschrift für Psychologie ◽

10.1027/2151-2604/a000422 ◽

2020 ◽

Vol 228 (4) ◽

pp. 244-253 ◽

Cited By ~ 1

Author(s):

Sonja Kälin ◽

Claudia M. Roebers

Keyword(s):

Working Memory ◽

Executive Functions ◽

Cognitive Processes ◽

Higher Order ◽

Kindergarten Children ◽

Metacognitive Monitoring

Abstract. Repeatedly, the notion has been put forward that metacognition (MC) and executive functions (EF) share common grounds, as both describe higher order cognitive processes and involve monitoring. However, only few studies addressed this issue empirically and so far their findings are rather inconsistent. Addressing the question whether measurement differences may in part be responsible for the mixed results, the current study included explicitly reported as well as time-based measures of metacognitive monitoring and related them to EF. A total of 202 children aged 4–6 years were assessed in terms of EF (inhibition, working memory, shifting) and monitoring. While there was no significant link between explicitly reported confidence and EF, latencies of monitoring judgments were significantly related to time- and accuracy-based measures of EF. Our findings support the association between EF and MC and the assumption that better inhibition abilities help children to engage in more thorough monitoring.

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