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508
Task-switching and long-term priming: Role of episodic stimulus-task bindings in task-shift costs
, 2003
"... WhH subjectsswitch between two tasks, performance is slower after a taskswitch tht after a task repetition. We report five experimentsshperi thp a large part ofth)I "task-sh5S) costs" cannot be attributed to a control operation, needed to configureth cognitive system for th upcomi ..."
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Cited by 112 (21 self)
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WhH subjectsswitch between two tasks, performance is slower after a taskswitch tht after a task repetition. We report five experimentsshperi thp a large part ofth)I "task-sh5S) costs" cannot be attributed to a control operation, needed to configureth cognitive system for th upcoming task (e.g., Rogers & Monsell, 1995). In all experiments subjects switchs between picture-naming and word-reading. We presented di#erent stimulieithl in just one of th two tasks, or inboth ofth9S ShSI#qH(93 were larger for stimuli presented inboth tasks ths forthH3 presented in only one task, even after more the 100 intervening trials between prime and probe events. We suggest (as proposed by Allport & Wylie, 2000)th0 stimuli acquire associationswith th tasks inwh9E th9 occur.Whu th current task activation is weak, as on aswitch of tasks, stimuli can trigger retrieval of th associated, competing task, provoking larger time costs.
Task switching: A PDP model
- Cognitive Psychology
, 2002
"... When subjects switch between a pair of stimulus–response tasks, reaction time is slower on trial N if a different task was performed on trial N 2 1. We present a parallel distributed processing (PDP) model that simulates this effect when subjects switch between word reading and color naming in respo ..."
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Cited by 104 (4 self)
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When subjects switch between a pair of stimulus–response tasks, reaction time is slower on trial N if a different task was performed on trial N 2 1. We present a parallel distributed processing (PDP) model that simulates this effect when subjects switch between word reading and color naming in response to Stroop stimuli. Reac-tion time on ‘‘switch trials’ ’ can be slowed by an extended response selection process which results from (a) persisting, inappropriate states of activation and inhibition of task-controlling representations; and (b) associative learning, which allows stimuli to evoke tasks sets with which they have recently been associated (as proposed by Allport & Wylie, 2000). The model provides a good fit to a large body of empirical data, including findings which have been seen as problematic for this explanation of switch costs, and shows similar behavior when the parameters are set to random values, supporting Allport and Wylie’s proposal. ª 2001 Elsevier Science (USA) Key Words: task switching; task set; Stroop effect; parallel distributed processing; executive functions. Atkinson and Shiffrin (1968) proposed a distinction between relatively permanent cognitive structures, such as short- and long-term memory, and control processes which harness those fixed structures in order to attain spe-cific goals. This distinction was elaborated in the following years (e.g.,
Goal-referenced selection of verbal action: Modeling attentional control in the Stroop task
- Psychological Review
, 2003
"... This article presents a new account of the color-word Stroop phenomenon (J. R. Stroop, 1935) based on ..."
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Cited by 104 (32 self)
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This article presents a new account of the color-word Stroop phenomenon (J. R. Stroop, 1935) based on
Mindfulness: A proposed operational definition
- Clinical Psychology: Science & Practice
, 2004
"... There has been substantial interest in mindfulness as an approach to reduce cognitive vulnerability to stress and emotional distress in recent years. However, thus far mindfulness has not been defined operationally. This paper describes the results of recent meetings held to establish a consensus on ..."
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Cited by 104 (4 self)
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There has been substantial interest in mindfulness as an approach to reduce cognitive vulnerability to stress and emotional distress in recent years. However, thus far mindfulness has not been defined operationally. This paper describes the results of recent meetings held to establish a consensus on mindfulness and to develop conjointly a testable operational definition. We propose a two-component model of mindfulness and specify each component in terms of specific behaviors, experiential manifestations, and implicated psychological processes. We then address issues regarding temporal stability and situational specificity and speculate on the conceptual and operational distinctiveness of mindfulness. We conclude this paper by discussing implications for instrument development and briefly describing our own approach to measurement.
Clever homunculus: Is there an endogenous act of control in the explicit task-cuing procedure
- Journal of Experimental Psychology: Human Perception and Performance
, 2003
"... Does the explicit task-cuing procedure require an endogenous act of control? In 5 experiments, cues indicating which task to perform preceded targets by several stimulus onset asynchronies (SOAs). Two models were developed to account for changes in reaction time (RT) with SOA. Model 1 assumed an end ..."
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Cited by 103 (20 self)
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Does the explicit task-cuing procedure require an endogenous act of control? In 5 experiments, cues indicating which task to perform preceded targets by several stimulus onset asynchronies (SOAs). Two models were developed to account for changes in reaction time (RT) with SOA. Model 1 assumed an endogenous act of task switching for cue alternations but not for cue repetitions. Model 2 assumed no such act. In Experiments 1 and 2, the cue was masked or not masked. Masking interacted underadditively with repetition and alternation, consistent with Model 2 but not Model 1. In Experiments 3 and 4, 2 cues were used for each task. RT was slower for task repetition than for cue repetition and about the same as RT for task alternation, consistent with Model 2 but not Model 1. The results suggest that the explicit task-cuing procedure does not require an endogenous act of control. Clever Hans was a remarkable horse who could add, subtract, multiply, and divide numbers, working with fractions as well as integers. His owner, von Osten, would ask him questions and Hans would tap out the answers with his hoof. An early experimental psychologist, Oskar Pfungst (1907, 1911), investigated Hans’s ability and found that the horse responded to subtle visual cues
Neuroimaging studies of shifting attention: a meta-analysis. [Meta-Analysis
- Neuroimage
, 2004
"... This paper reports a meta-analysis of neuroimaging studies of attention shifting and executive processes in working memory. We analyzed peak activation coordinates from 31 fMRI and PET studies of five types of shifting using kernel-based methods [NeuroImage 19 (2003) 513]. Analyses collapsing across ..."
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Cited by 103 (18 self)
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This paper reports a meta-analysis of neuroimaging studies of attention shifting and executive processes in working memory. We analyzed peak activation coordinates from 31 fMRI and PET studies of five types of shifting using kernel-based methods [NeuroImage 19 (2003) 513]. Analyses collapsing across different types of shifting gave more consistent results overall than analysis within individual types, suggesting a commonality across types of shifting. These areas shared substantial, significant overlap with regions derived from kernel-based analyses of reported peaks for executive processes in working memory (WM). The results suggest that there is a common set of brain regions active in diverse executive control operations, including medial prefrontal, superior and inferior parietal, medial parietal, and premotor cortices. However, within several of these regions, different types of switching produced spatially discriminable activation foci. Precise locations of meta analysis-derived regions from both attention shifting and working memory are defined electronically and may be used as regions of interest in future studies.
Threaded cognition: An integrated theory of concurrent multitasking
- Psychological Review
, 2008
"... The authors propose the idea of threaded cognition, an integrated theory of concurrent multitasking—that is, performing 2 or more tasks at once. Threaded cognition posits that streams of thought can be represented as threads of processing coordinated by a serial procedural resource and executed acro ..."
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Cited by 101 (38 self)
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The authors propose the idea of threaded cognition, an integrated theory of concurrent multitasking—that is, performing 2 or more tasks at once. Threaded cognition posits that streams of thought can be represented as threads of processing coordinated by a serial procedural resource and executed across other available resources (e.g., perceptual and motor resources). The theory specifies a parsimonious mechanism that allows for concurrent execution, resource acquisition, and resolution of resource conflicts, without the need for specialized executive processes. By instantiating this mechanism as a computational model, threaded cognition provides explicit predictions of how multitasking behavior can result in interference, or lack thereof, for a given set of tasks. The authors illustrate the theory in model simulations of several representative domains ranging from simple laboratory tasks such as dual-choice tasks to complex real-world domains such as driving and driver distraction.
Adult age differences in task switching
- Psychology and Aging
, 2000
"... Age differences in 2 components of task-set switching speed were investigated in 118 adults aged 20 to 80 years using task-set homogeneous (e.g., AAAA... ) and task-set heterogeneous (e.g., AABBAABB...) blocks. General switch costs were defined as latency differences between heteroge-neous and homog ..."
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Cited by 90 (5 self)
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Age differences in 2 components of task-set switching speed were investigated in 118 adults aged 20 to 80 years using task-set homogeneous (e.g., AAAA... ) and task-set heterogeneous (e.g., AABBAABB...) blocks. General switch costs were defined as latency differences between heteroge-neous and homogeneous blocks, whereas pecific switch costs were defined as differences between switch and nonswitch trials within heterogeneous blocks. Both types of costs generalized over verbal, figural, and numeric stimulus materials; were more highly correlated to fluid than to crystallized abilities; and were not eliminated after 6 sessions of practice, indicating that they reflect basic and domain-general aspects of cognitive control. Most important, age-associated increments in costs were significantly greater for general than for specific switch costs, suggesting that the ability to efficiently maintain and coordinate 2 alternating task sets in working memory instead of 1 is more negatively affected by advancing age than the ability to execute the task switch itself. Cognitive control processes are generally seen as responsible for the regulation and organization of behavioral activity (Baddeley, 1986; Norman & Shallice, 1986). Influenced by the neuropsycho-logical research tradition, developmental researchers have become increasingly interested in the role of cognitive control processes for the regulation of behavior and in their relationship to age-related decrements in fluid intelligence or the mechanics of cog-nition (e.g., Baltes, 1993). Theoretical considerations about aging models of cognitive control are dominated by the frontal lobe hypothesis of aging, which assumes that age-related ecline in intellectual functioning is associated with age-based changes in the frontal lobe (Dempster, 1992; Duncan, 1995; Prull, Gabrieli, & Bunge, in press). This line of thinking has been primarily influ-enced by clinical observations of behavioral deficits in frontal obe patients (Reitan & Wolfson, 1994; Shallice & Burgess, 1993;
Positive affect modulates cognitive control: Reduced perseveration at the cost of increased distractibility
- EFFECTS OF SEX AND EMOTIONAL VALENCE ON SUPPRESSION 71
, 2004
"... A fundamental problem that organisms face in a changing environment is how to regulate dynamically the balance between stable maintenance and flexible switching of goals and cognitive sets. The authors show that positive affect plays an important role in the regulation of this stability–flexibility ..."
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Cited by 81 (1 self)
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A fundamental problem that organisms face in a changing environment is how to regulate dynamically the balance between stable maintenance and flexible switching of goals and cognitive sets. The authors show that positive affect plays an important role in the regulation of this stability–flexibility balance. In a cognitive set-switching paradigm, the induction of mild increases in positive affect, as compared with neutral or negative affect, promoted cognitive flexibility and reduced perseveration, but also incurred a cost in terms of increased distractibility. Rather than influencing set switching in an unspecific way, positive affect thus exerted opposite effects on perseveration and distractibility. Results are consistent with neuropsychological models according to which effects of positive affect on cognitive control are mediated by increased dopamine levels in frontal brain areas. Intelligent organisms pursuing goal-directed behavior in a con-stantly changing environment face two fundamental challenges: to maintain current goals over time in the face of distraction on the one hand, and to flexibly switch between goals and update working memory in response to significant changes on the other (Goschke, 1996, 2000, 2003; cf. Mayr & Keele, 2000; O’Reilly, Braver, &
An instance theory of attention and memory
- Psychological Review
, 2002
"... An instance theory of attention and memory (ITAM) is presented that integrates formal theories of attention and memory phenomena by exploiting commonalities in their formal structure. The core idea in each theory is that performance depends on a choice process that can be modeled as a race between c ..."
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Cited by 78 (10 self)
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An instance theory of attention and memory (ITAM) is presented that integrates formal theories of attention and memory phenomena by exploiting commonalities in their formal structure. The core idea in each theory is that performance depends on a choice process that can be modeled as a race between competing alternatives. Attention and categorization are viewed as different perspectives on the same race. Attention selects objects by categorizing them; objects are categorized by attending to them. ITAM incorporates each of its ancestors as a special case, so it inherits their successes. Imagine yourself on your way home from work. You walk into the parking lot and look for your car. It takes you a second, perhaps. Now imagine your colleagues analyzing the simple act of cognition underlying that look. A student of attention would be interested in how your gaze went to the cars rather than other structural features. A student of categorization would be interested in how you knew those were cars in the parking lot. And a student of memory would be interested in how you did (or did not) pick your own car out of the group. These differences in perspective
