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A key index of top-down control in task switching--preparation for a switch--is underexplored in language switching. The well-documented EEG "signature" of preparation for a task switch--a protracted positive-polarity modulation over the posterior scalp--has thus far not been reported in language switching, and the interpretation of previously reported effects of preparation on language switching performance is complicated by confounding factors. In an experiment using event-related potentials (ERPs) and an optimized picture-naming paradigm that addressed these confounds the language was specified by an auditory cue on every trial and changed unpredictably. There were two key manipulations. First, the cue-stimulus interval allowed either generous (1,500 ms) or little (100 ms) opportunity for preparation. Second, to explore the interplay between bottom-up and top-down language selection, we compared a highly transparent and familiar "supercue"--the name of the language spoken in that language to a relatively opaque cue (short speeded-up fragment of national anthem). Preparation for a switch elicited a brain potential strongly reminiscent of the posterior switch positivity documented in task switching. As previously shown in task switching, its amplitude inversely predicted the performance "switch cost," demonstrated by our ERP analyses contingent on reaction time (RT). This overlap in the electrophysiological correlates of preparing to switch tasks and languages suggests domain-general processes for top-down selection of task-set and language for production. But, the surprisingly small language switch cost following the supercue in the short CSI suggests that rapid and (possibly automatic) bottom-up selection--not typically observed in task switching--may also occur.

The performance overhead associated with changing tasks (the "switch cost") usually diminishes when the task is specified in advance but is rarely eliminated by preparation. A popular account of the "residual" (asymptotic) switch cost is that it reflects "task-set inertia": carry-over of task-set parameters from the preceding trial(s). New evidence for a component of "task-set inertia" comes from eye-tracking, where the location associated with the previously (but no longer) relevant task is fixated preferentially over other irrelevant locations, even when preparation intervals are generous. Might such limits in overcoming task-set inertia in general, and "attentional inertia" in particular, result from suboptimal scheduling of preparation when the time available is outside one's control? In the present study, the stimulus comprised 3 digits located at the points of an invisible triangle, preceded by a central verbal cue specifying which of 3 classification tasks to perform, each consistently applied to just 1 digit location. The digits were presented only when fixation moved away from the cue, thus giving the participant control over preparation time. In contrast to our previous research with experimenter-determined preparation intervals, we found no sign of attentional inertia for the long preparation intervals. Self-paced preparation reduced but did not eliminate the performance switch cost--leaving a clear residual component in both reaction time and error rates. That the scheduling of preparation accounts for some, but not all, components of the residual switch cost, challenges existing accounts of the switch cost, even those which distinguish between preparatory and poststimulus reconfiguration processes.

Task-cuing experiments are usually intended to explore control of task set. But when small stimulus sets are used, they plausibly afford learning of the response associated with a combination of cue and stimulus, without reference to tasks. In 3 experiments we presented the typical trials of a task-cuing experiment: a cue (colored shape) followed, after a short or long interval, by a digit to which 1 of 2 responses was required. In a tasks condition, participants were (as usual) directed to interpret the cue as an instruction to perform either an odd/even or a high/low classification task. In a cue + stimulus ? response (CSR) condition, to induce learning of mappings between cue-stimulus compound and response, participants were, in Experiment 1, given standard task instructions and additionally encouraged to learn the CSR mappings; in Experiment 2, informed of all the CSR mappings and asked to learn them, without standard task instructions; in Experiment 3, required to learn the mappings by trial and error. The effects of a task switch, response congruence, preparation, and transfer to a new set of stimuli differed substantially between the conditions in ways indicative of classification according to task rules in the tasks condition, and retrieval of responses specific to stimulus-cue combinations in the CSR conditions. Qualitative features of the latter could be captured by an associative learning network. Hence associatively based compound retrieval can serve as the basis for performance with a small stimulus set. But when organization by tasks is apparent, control via task set selection is the natural and efficient strategy.

Accounts of task-set control generally assume that the current task's stimulus-response (S-R) rules must be elevated to a privileged state of activation. How are they represented in this state? In 3 task-cuing experiments, we tested the hypothesis that phonological working memory is used to represent S-R rules for task-set control by getting participants to switch between 2 sets of arbitrary S-R rules and manipulating the articulatory duration (Experiment 1) or phonological similarity (Experiments 2 and 3) of the names of the stimulus terms. The task cue specified which of 2 objects (Experiment 1) or consonants (Experiment 2) in a display to identify with a key press. In Experiment 3, participants switched between identifying an object/consonant and its color/visual texture. After practice, neither the duration nor the similarity of the stimulus terms had detectable effects on overall performance, task-switch cost, or its reduction with preparation. Only in the initial single-task training blocks was phonological similarity a significant handicap. Hence, beyond a very transient role, there is no evidence that (declarative) phonological working memory makes a functional contribution to representing S-R rules for task-set control, arguably because once learned, they are represented in nonlinguistic procedural working memory.

Switching tasks prolongs response times, an effect reduced but not eliminated by active preparation. To explore the role of attentional selection of the relevant stimulus attribute in these task-switch costs, we measured eye fixations in participants cued to identify either a face or a letter displayed on its forehead. With only 200 ms between cue and stimulus onsets, the eyes fixated the currently relevant region of the stimulus less and the irrelevant region more on switch than on repeat trials, at stimulus onset and for 500 ms thereafter, in a pattern suggestive of delayed orientation of attention to the relevant region on switch trials. With 800 ms to prepare, both switch costs and inappropriate fixations were reduced, but on switch trials participants still tended (relative to repeat trials) to fixate the now-irrelevant region more at stimulus onset and to maintain fixation on, or refixate, the irrelevant region more during the next 500 ms. The size of this attentional persistence was associated with differences in performance costs between and within participants. We suggest that reorientation of attention is an important, albeit somewhat neglected and controversial, component of advance task-set reconfiguration and that the task-set inertia (or reactivation) to which many attribute the residual task-switch cost seen after preparation includes inertia in (or reactivation of) attentional parameters.

In 6 task-cuing experiments, with 2 cues per task, the authors varied cue-stimulus interval to investigate G. D. Logan and C. Bundesen's (2003) claim that when cue repetition is controlled for, task-switch cost and its reduction with preparation are largely eliminated and hence cannot index an endogenous control process. Experiment 1 replicates their result, but Experiments 2 and 3, with similar designs, demonstrate a substantial task-switch cost, reducing with increasing cue-stimulus interval. Experiments 4 to 6 show that the critical difference is the probability of a task change: If it is kept low enough to discourage reconfiguration of task set unless and until the cue signals a task change, robust evidence for anticipatory task-set reconfiguration is obtained, even in Experiment 6, modeled closely on Logan and Bundesen's.

In four experiments, Japanese readers were required to switch between reading words in Kanji and Kana. In every case, performance was significantly slower and less accurate on the trials following a change of script. (Author/VWL)

Four experiments investigated the effect of recent selective practice on the cost of switching between 2 tasks afforded by letter-digit pairs: alphabet arithmetic and shape comparison. Experiments 1 and 2 found a greater cost associated with switching to the more recently practiced task: evidence that task-set inertia contributes to switching costs. Experiment 3 found this effect to be limited to trials on which a recently trained stimulus followed another such stimulus: a result problematic for all current theories of task-set priming. Experiment 4 showed that the effect of recent practice was eliminated by active preparation for a task switch: It appears that endogenous task-set preparation reduces the effects of task-set inertia.

It has been reported that it is harder to switch to a strong, well-practiced task from a weaker, less-practiced task than vice versa. Three experiments replicated this surprising asymmetry and investigated how it is affected by a reduction in interference between tasks. Experiment 1 progressively delayed the onset of the stimulus attribute associated with the stronger task. Experiments 2 and 3 separated the response sets of the tasks. Both manipulations reduced, without eliminating, interference of the stronger with the weaker task but reversed the asymmetry of switch costs, resulting in a larger cost of switching to the weaker task. The results are interpreted in terms of a model of the interactions between control input, task strength, and task priming.

The relationship between the disorder-salient Stroop effect and the psychopathology of eating disorders was investigated. Thirty-two female subjects participated in the experiment that used four word types to determine the amount of Stroop interference in women with eating disorders. Results show that patients with anorexia nervosa displayed a slower response to color-name words relating to food and eating as well as weight and shape than patients with bulimia nervosa. Also, there was no reliable interference effect for a set of emotion words in patients with anorexia nervosa.

In an investigation of task-set reconfiguration, participants switched between 2 tasks on every 2nd trial in 5 experiments and on every 4th trial in a final experiment. The tasks were to classify either the digit member of a pair of characters as even/odd or the letter member as consonant/vowel. As the response-stimulus interval increased up to 0.6 s, the substantial cost to performance of this predictable task-switch fell: Participants could partially reconfigure in advance of the stimulus. However, even with 1.2 s available for preparation, a large asymptotic reaction time (RT) cost remained, but only on the 1st trial of the new task. This is attributed to a component of reconfiguration triggered exogenously, i.e., only by a task-relevant stimulus. That stimuli evoke associated task-sets also explains why RT and switch costs increased when the stimulus included a character associated with the currently irrelevant task.

Two experiments on oral reading of single words compared naming performance in pure blocks of nonwords or exception words with performance in blocks of randomly mixed nonwords and exception words. Ss named exception words faster and made fewer regularization errors when they were not also prepared for nonwords. These data suggest Ss inhibit or ignore the computation of assembled phonology when only exception words are expected. Ss named nonwords faster, but no more accurately, when low-frequency exception words were not also anticipated. Thus, Ss' readiness to execute assembled phonology appears to be adjusted in relation to the likely time course of retrieval of learned pronunciations, when the latter must be attended to. This evidence for strategic dissociation between sublexical and lexical translation is discussed in relation to current models.

In replying to Balota and Chumbley's (1990) commentary on Monsell, Doyle, and Haggard's (1989) article, the author addresses four issues. New data show that the effect of frequency on semantic categorization time reported by Monsell et al. was not a disguised typicality effect. An account of the small size of the effect of stress pattern on immediate naming latency observed by Monsell et al. is supplied. Inferences that may and may not be drawn from effects of frequency on delayed naming latency are discussed. The main conclusions and methodological recommendations of Monsell et al. are clarified.

Provides an introduction to research on the basic components of cognitive skill. Perceptual processing and representation, the components of long- and short-term memory, and the nature of attention, mental performance, and consciousness are discussed. A 101-item reference list is provided. (JL)

This article argues that the dual-process position can be a useful first approximation when studying human mental life, but it cannot be the whole truth. Instead, we argue that cognition is built on association, in that associative processes provide the fundamental building blocks that enable propositional thought. One consequence of this position is to suggest that humans are able to learn associatively in a similar fashion to a rat or a pigeon, but another is that we must typically suppress the expression of basic associative learning in favour of rule-based computation. This stance conceptualises us as capable of symbolic computation but acknowledges that, given certain circumstances, we will learn associatively and, more importantly, be seen to do so. We present three types of evidence that support this position: The first is data on human Pavlovian conditioning that directly support this view. The second is data taken from task-switching experiments that provide convergent evidence for at least two modes of processing, one of which is automatic and carried out "in the background." And the last suggests that when the output of propositional processes is uncertain, the influence of associative processes on behaviour can manifest. [ABSTRACT FROM AUTHOR]