Domain-general Mechanisms Research Articles

Rattling the cage and opening the door.

I share with Poulin-Dubois and with Sabbagh, Koenig and Kuhlmeier the conviction that more research is needed on the mechanisms supporting selective social learning in infants and children. However, my plea is more specific: for research that tests domain-specific hypotheses about mechanism against domain-general hypotheses derived from other fields of cognitive science. Many, but not all, of these alternative hypotheses relate to domain-general mechanisms of attention.

Executive Functions and the Improvement of Thinking Abilities: The Intervention in Reading Comprehension.

In this paper, we propose a preliminary theory of executive functions that address in a specific way their relationship with working memory (WM) and higher-level cognition. It includes: (a) four core on-line WM executive functions that are involved in every novel and complex cognitive task; (b) two higher order off-line executive functions, planning and revision, that are required to resolving the most complex intellectual abilities; and (c) emotional control that is involved in any complex, novel and difficult task. The main assumption is that efficiency on thinking abilities may be improved by specific instruction or training on the executive functions necessary to solving novel and complex tasks involved in these abilities. Evidence for the impact of our training proposal on WM's executive functions involved in higher-level cognitive abilities comes from three studies applying an adaptive program designed to improve reading comprehension in primary school students by boosting the core WM's executive functions involved in it: focusing on relevant information, switching (or shifting) between representations or tasks, connecting incoming information from text with long-term representations, updating of the semantic representation of the text in WM, and inhibition of irrelevant information. The results are consistent with the assumption that cognitive enhancements from the training intervention may have affected not only a specific but also a more domain-general mechanism involved in various executive functions. We discuss some methodological issues in the studies of effects of WM training on reading comprehension. The perspectives and limitations of our approach are finally discussed.

Cognitive and brain systems underlying early mathematical development.

We review current debate regarding the core competencies that support early mathematics learning, focusing on the contributions of the inherent system for representing approximate magnitudes, and domain-general systems that facilitate learning across academic domains. The latter include the executive control system that enables explicit processing of quantitative symbols, such as Arabic numerals, and the logical problem-solving abilities (intelligence) that facilitate learning the relations among numerals. The neural systems that underlie these abilities, as related to mathematical learning, are also discussed, albeit briefly. We place the contributions of inherent quantitative abilities and domain-general mechanisms in an evolutionary context and provide some discussion as to how they interact during the learning of evolutionarily novel mathematics.

The nature of working memory gating in Parkinson's disease: A multi-domain signal detection examination.

Distractions are ubiquitous; our brains are inundated with task-irrelevant information. Thus, to remember successfully, one must actively maintain relevant information and prevent distraction from entering working memory. Researchers suggest the basal ganglia-prefrontal pathways are vital to this process by acting as a working memory gate. Using Parkinson's disease as a model of frontostriatal functioning and with signal detection analyses, the present study aims to better characterize the contribution of frontostriatal pathways of this gating process and to determine how it operates across multiple domains. To achieve this, Parkinson's disease patients and healthy controls completed verbal and spatial working memory tasks consisting of three conditions: low-load without distraction; low-load with distraction; and high-load without distraction. Patients were tested both ON and OFF dopaminergic medication, allowing for assessment of the contribution of dorsal and ventral frontostriatal pathways. The results demonstrate that when medication is withheld, Parkinson's patients have a response bias to answer "NO" across all conditions and domains, supporting our hypothesis that the basal ganglia-prefrontal pathways allow or prevent updates of working memory. Contrastingly, medication status affects d' in the distraction condition but not in the high- or low-load conditions. We attribute this to stimulus valuation processes that were impaired by dopaminergic medication overdosing the ventral pathway. These findings are both consistent with the hypothesis that the working memory gate filters spatial and verbal information before it enters into the working memory system, adding support for the gate being a domain-general mechanism of the central executive.

The mind behind anthropomorphic thinking: attribution of mental states to other species

Humans readily attribute intentionality and mental states to living and nonliving entities, a phenomenon known as anthropomorphism. Recent efforts to understand the driving forces behind anthropomorphism have focused on its motivational underpinnings. By contrast, the underlying cognitive and neuropsychological processes have not been considered in detail so far. The marked increase in interest in anthropomorphism and its consequences for animal welfare, conservation and even as a potential constraint in animal behaviour research call for an integrative review. We identify a set of potential cognitive mechanisms underlying the attribution of mental states to nonhuman animals using a dual process framework. We propose that mental state attributions are supported by processes evolved in the social domain, such as motor matching mechanisms and empathy, as well as by domain-general mechanisms such as inductive and causal reasoning. We conclude that the activation of these domain-specific and domain-general mechanisms depend on the type of information available to the observer, and suggest a series of hypotheses for testing the proposed model.

The simple advantage in perceptual and categorical generalization.

Recent research in relational learning has suggested that simple training instances may lead to better generalization than complex training instances. We examined the perceptual-encoding mechanisms that might undergird this "simple advantage" by testing category and perceptual learning in adults with simplified and traditional (more complex) Chinese scripts. In Experiment 1, participants learned Chinese characters and their English translations, performed a memorization test, and generalized their learning to the corresponding characters written in the other script. In Experiment 2, we removed the training phase and modified the tests to examine transfer based purely on the perceptual similarities between simplified and traditional characters. We found the simple advantage in both experiments. Training with simplified characters produced better generalization than training with traditional characters when generalization relied on either recognition memory or pure perceptual similarities. On the basis of the results of these two experiments, we propose a simple process model to explain the perceptual mechanism that might drive this simple advantage, and in Experiment 3 we tested novel predictions of this model by examining the effect of exposure duration on the simple advantage. We found support for our model that the simple advantage is driven primarily by differences in the perceptual encoding of the information available from simple and complex instances. These findings advance our understanding of how the perceptual features of a learning opportunity interact with domain-general mechanisms to prepare learners for transfer.

The cognitive structure of goal emulation during the preschool years.

Humans excel at mirroring both others' actions (imitation) as well as others' goals and intentions (emulation). As most research has focused on imitation, here we focus on how social and asocial learning predict the development of goal emulation. We tested 215 preschool children on two social conditions (imitation, emulation) and two asocial conditions (trial-and-error and recall) using two touch screen tasks. The tasks involved responding to either three different pictures in a specific picture order (Cognitive: apple→boy→cat) or three identical pictures in a specific spatial order (Motor-Spatial: up→down→right). Generalized linear models demonstrated that during the preschool years, Motor-Spatial emulation is associated with social and asocial learning, while cognitive emulation is associated only with social learning, including motor-spatial emulation and multiple forms of imitation. This result contrasts with those from a previous study using this same data set showing that motor-spatial and cognitive imitation were neither associated with one another nor, generally, predicted by other forms of social or asocial learning. Together, these results suggests that while developmental changes in imitation are associated with multiple - specialized - mechanisms, developmental changes in emulation are associated with age-related changes and a more unitary, domain-general mechanism that receives input from several different cognitive and learning processes, including some that may not necessarily be specialized for social learning.

The Timing of Regular Sequences: Production, Perception, and Covariation.

The temporal structure of behavior provides information that allows the tracking of temporal regularity in the sensory and sensorimotor domains. In turn, temporal regularity allows the generation of predictions about upcoming events and to adjust behavior accordingly. These mechanisms are essential to ensure behavior beyond the level of mere reaction. However, efficient temporal processing is required to establish adequate internal representations of temporal structure. The current study used two simple paradigms, namely, finger-tapping at a regular self-chosen rate (spontaneous motor tempo) and ERPs of the EEG (EEG/ERP) recorded during attentive listening to temporally regular and irregular "oddball" sequences to explore the capacity to encode and use temporal regularity in production and perception. The results show that specific aspects of the ability to time a regular sequence of events in production covary with the ability to time a regular sequence in perception, probably pointing toward the engagement of domain-general mechanisms.

Attention allocation: Relationships to general working memory or specific language processing

Attention allocation, updating working memory, and language processing are interdependent cognitive tasks related to the focused direction of limited resources, refreshing and substituting information in the current focus of attention, and receiving/sending verbal communication, respectively. The current study systematically examined the relationship among executive attention, working memory executive skills, and language abilities while adjusting for individual differences in short-term memory. School-age children completed a selective attention task requiring them to recall whether a presented shape was in the same place as a previous target shape shown in an array imposing a low or high working memory load. Results revealed a selective attention cost when working above but not within memory span capacity. Measures of general working memory were positively related to overall task performance, whereas language abilities were related to response time. In particular, higher language skills were associated with faster responses under low load conditions. These findings suggest that attentional control and storage demands have an additive impact on working memory resources but provide only limited evidence for a domain-general mechanism in language learning.

Evolved computers with culture. Commentary: From computers to cultivation: reconceptualizing evolutionary psychology

Evolved computers with culture. Commentary: From computers to cultivation: reconceptualizing evolutionary psychology

Evolved to adapt: A computational approach to animal innovation and creativity

Abstract The production of novel behavioral sequences that gives rise to animal innovation and creativity is one of the most intriguing aspects of behavioral evolution. Numerous studies have recently documented the abundance and diversity of innovative and creative behaviors between and within species, yet the ability to innovate or to act creatively has mainly been described and quantified as a measure of animals’ cognitive abilitywithout explicit reference to cognitive mechanismsthat may account for these behaviors. Here we discuss the creative process from a computational point of view and suggest such a mechanistic framework. In light of recent research on human creativity, animal learning, and animal problem solving, we suggest that animal creativity is best understood as the production of context-appropriate novel behavioral sequences, which may be facilitated by the ability to learn the regularities in the environment and to represent them hierarchically, allowing for generalization. We present a cognitive framework that we recently developed, which employs domain-general mechanisms and has been used in the modeling of a range of sequential behaviors, from animal foraging to language acquisition, and apply it to behavioral innovation. In a series of simulations, we show how innovation and creative behavior can be produced by this learning mechanism, as it constructs a network representing the statistical regularities of the environment. We use the simulations to demonstrate the role of particular cognitive parameters in this process and to highlight the effects of the learning dynamics and individual experience on creativity.

Search and the Aging Mind: The Promise and Limits of the Cognitive Control Hypothesis of Age Differences in Search.

Search is a prerequisite for successful performance in a broad range of tasks ranging from making decisions between consumer goods to memory retrieval. How does aging impact search processes in such disparate situations? Aging is associated with structural and neuromodulatory brain changes that underlie cognitive control processes, which in turn have been proposed as a domain-general mechanism controlling search in external environments as well as memory. We review the aging literature to evaluate the cognitive control hypothesis that suggests that age-related change in cognitive control underlies age differences in both external and internal search. We also consider the limits of the cognitive control hypothesis and propose additional mechanisms such as changes in strategy use and affect that may be necessary to understand how aging affects search.

Slowing Down Fast Mapping: Redefining the Dynamics of Word Learning.

In this article, we review literature on word learning and propose a theoretical account of how lexical knowledge and word use emerge and develop over time. We contend that the developing lexical system is built on processes that support children's in-the-moment word usage interacting with processes that create long-term learning. We argue for a new characterization of word learning in which simple mechanisms like association and competition, and the interaction between the two, guide children's selection of referents and word use in the moment. This in turn strengthens and refines the network of relationships in the lexicon, improving referent selection and use in future encounters with words. By integrating in-the-moment word use with long-term learning through simple domain-general mechanisms, this account highlights the dynamic nature of word learning and creates a broader framework for understanding language and cognitive development more generally.

Music training and inhibitory control: a multidimensional model.

Training programs aimed to improve cognitive skills have either yielded mixed results or remain to be validated. The limited benefits of such regimens are largely attributable to weak understanding of (1) how (and which) interventions provide the most cognitive improvements; and (2) how brain networks and neural mechanisms that underlie specific cognitive abilities can be modified selectively. Studies indicate that music training leads to robust and long-lasting benefits to behavior. Importantly, behavioral advantages conferred by music extend beyond perceptual abilities to even nonauditory functions, such as inhibitory control (IC) and its neural correlates. Alternative forms of arts engagement or brain training do not appear to yield such enhancements, which suggests that music uniquely taps into brain networks subserving a variety of auditory as well as domain-general mechanisms such as IC. To account for such widespread benefits of music training, we propose a framework of transfer effects characterized by three dimensions: level of processing, nature of the transfer, and involvement of executive functions. We suggest that transfer of skills is mediated through modulation of general cognitive processes, in particular IC. We believe that this model offers a viable framework to test the extent and limitations of music-related changes.

Fast neural dynamics of a 'multiple demand'� frontoparietal network for cognitive control

Event Abstract Back to Event Fast neural dynamics of a 'multiple demand' frontoparietal network for cognitive control Francisco Barcelo1, Álvaro Darriba1*, Javier Villacampa1, Rosa Martorell1, Marcelina Chamielec1 and Alejandro Gálvez1 1 University of the Balearic Islands, Spain Cognitive flexibility is critical for adaptive human behavior in complex societies with ever growing multitasking demands. Yet the fast neural dynamics of task-specific and domain-general mechanisms subserving mental flexibility are still ill defined. In this study, we recorded event-related potentials (ERPs) from 36 participants while they were intermittently cued to switch or repeat their perceptual categorization of Gabor gratings varying in color and thickness (Switch task), or else they performed two visually identical control tasks (NoGo and Oddball). Our task cueing paradigm was designed to examine proactive and reactive control modes during both cue-locked rule preparation and target-locked rule implementation stages. Unlike past studies, we addressed trial-by-trial dynamics of sensorimotor, contextual and episodic control operations ensuing task transition points. Both switch-specific (indexed by cue-locked P600 and a sustained target-locked positivity following task transitions) and domain-general mechanisms (indexed by cue- and target-locked P2 and P3 components) revealed fast recurrent modulations of neural activity within a common frontoparietal network. Topographic analyses of normalized brain responses revealed distinct split-second swings of activation across posterior and frontal scalp regions as a function of increasing cognitive demands and proactive vs. reactive control modes. Modulations of domain-general brain potentials paralleled predictions from information theoretic models (Koechlin & Summerfield, 2007) that envisage cognitive control as a series of temporarily ordered processing stages at various levels within a hierarchy of representations (e.g., sensory, contextual, episodic) in the brain. Our results also suggested distinct functional roles for the fast and recursive activations observed within the frontoparietal "multiple demand" system (Duncan, 2013) during the preparation and implementation stages of task switching. Acknowledgements: Study supported by grants from Fundació La Marató de TV3 (112710) (FB); and Fellowship financed by the European Social Fund (ESF) and the Govern de les Illes Balears (Conselleria d’Educació, Cultura i Universitats) (MC). Keywords: executive control, P300, Context updating, Task-set inertia, Task-set reconfiguration Conference: XII International Conference on Cognitive Neuroscience (ICON-XII), Brisbane, Queensland, Australia, 27 Jul - 31 Jul, 2014. Presentation Type: Poster Topic: Cognition and Executive Processes Citation: Barcelo F, Darriba Á, Villacampa J, Martorell R, Chamielec M and Gálvez A (2015). Fast neural dynamics of a 'multiple demand' frontoparietal network for cognitive control. Conference Abstract: XII International Conference on Cognitive Neuroscience (ICON-XII). doi: 10.3389/conf.fnhum.2015.217.00043 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 19 Feb 2015; Published Online: 24 Apr 2015. * Correspondence: Dr. Álvaro Darriba, University of the Balearic Islands, Palma de Mallorca, Spain, alvaro.da.riba@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Francisco Barcelo Álvaro Darriba Javier Villacampa Rosa Martorell Marcelina Chamielec Alejandro Gálvez Google Francisco Barcelo Álvaro Darriba Javier Villacampa Rosa Martorell Marcelina Chamielec Alejandro Gálvez Google Scholar Francisco Barcelo Álvaro Darriba Javier Villacampa Rosa Martorell Marcelina Chamielec Alejandro Gálvez PubMed Francisco Barcelo Álvaro Darriba Javier Villacampa Rosa Martorell Marcelina Chamielec Alejandro Gálvez Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Fast dynamics of domain-general vs. specific neural mechanisms of task switching: Interactions between the frontoparietal and spatial orienting networks

Event Abstract Back to Event Fast dynamics of domain-general vs. specific neural mechanisms of task switching: Interactions between the frontoparietal and spatial orienting networks Marcelina Chamielec1, Álvaro Darriba1, Javier Villacampa1, Rosa Martorell1, Alejandro Gálvez1 and Francisco Barceló1* 1 University of Balearic Islands, Department of Psychology, Spain Task switching involves the selection, inhibition and updating of hierarchically ordered task-set (sensory, sensorimotor, contextual, episodic) representations in our brains. A frontoparietal executive network is recruited during both proactive and reactive control of task-switching, although its interactions with an anatomically independent spatial orienting network have not been addressed yet. The relative contributions from task-switch specific and domain-general mechanisms to the temporal dynamics of this frontoparietal network are still ill defined. This study addressed these questions by measuring event-related potentials (ERPs) from 19 young participants who were intermittently cued to switch or repeat their perceptual categorization of geometrical shapes varying in colour and form (Switch task), or else they performed two visually identical control tasks with lesser cognitive demands (NoGo and Oddball). Spatial orienting was manipulated as a task-irrelevant factor, with visual stimuli displayed either centrally or bilaterally in two separate trial blocks. Early cue- and target-locked P1 and N1 ERPs were modulated by spatial orienting only. Cue-locked P2 and P3 components reflected an interaction between spatial orienting, task demands, and switch-specific operations, as indexed by enhanced P2 or P3 amplitudes to switch cues displayed either bilaterally or centrally, respectively, relative to the other spatial location. The frontoparietal distributions of P2 and P3 swung towards more frontal regions for bilateral displays, presumably reflecting additional executive control in the face of higher spatial uncertainty. No such high-order interactions were found in the target-locked ERP waveforms. These results reveal crucial interactions between the frontoparietal and spatial orienting networks, and shed new light on the functional role of a frontoparietal "multiple demand" system (Duncan, 2013) during the preparation and implementation stages of task switching. Acknowledgements: Study supported by grants from Fundació La Marató de TV3 (112710) (FB); and Fellowship financed by the European Social Fund (ESF) and the Govern de les Illes Balears (Conselleria d’Educació, Cultura i Universitats) (MC). Keywords: executive control, P300, Context updating, Task-set inertia, Task-set reconfiguration Conference: XII International Conference on Cognitive Neuroscience (ICON-XII), Brisbane, Queensland, Australia, 27 Jul - 31 Jul, 2014. Presentation Type: Poster Topic: Cognition and Executive Processes Citation: Chamielec M, Darriba Á, Villacampa J, Martorell R, Gálvez A and Barceló F (2015). Fast dynamics of domain-general vs. specific neural mechanisms of task switching: Interactions between the frontoparietal and spatial orienting networks. Conference Abstract: XII International Conference on Cognitive Neuroscience (ICON-XII). doi: 10.3389/conf.fnhum.2015.217.00028 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 19 Feb 2015; Published Online: 24 Apr 2015. * Correspondence: Prof. Francisco Barceló, University of Balearic Islands, Department of Psychology, Palma de Mallorca, Spain, barcelo.paco@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Marcelina Chamielec Álvaro Darriba Javier Villacampa Rosa Martorell Alejandro Gálvez Francisco Barceló Google Marcelina Chamielec Álvaro Darriba Javier Villacampa Rosa Martorell Alejandro Gálvez Francisco Barceló Google Scholar Marcelina Chamielec Álvaro Darriba Javier Villacampa Rosa Martorell Alejandro Gálvez Francisco Barceló PubMed Marcelina Chamielec Álvaro Darriba Javier Villacampa Rosa Martorell Alejandro Gálvez Francisco Barceló Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Motor contributions to the perception of relative phase.

The extent to which different stimulus elements move together, namely their relative phase, is a central visual feature of many social and physical systems; characterizing everything from the oscillations of a walker’s limbs to the alternating lights at pedestrian crossings. The experiments described here provide the first evidence of a motor contribution to the representation of relative phase. Using an interference paradigm, we demonstrate that a motor load dramatically impairs discrimination of relative phase. Comparable interference effects were observed for biological and mechanical stimuli, indicative of a domain-general mechanism. In addition, we show that the same motor load has little effect on a similar static-angle matching task, and that an auditory rhythmic load did not interfere with phase discriminations in the same way as the motor load. These results suggest that the motor system contributes to the perception of relative phase; information crucial for interpreting our social and physical environments.

Domain-general mechanisms: what they are, how they evolved, and how they interact with modular, domain-specific mechanisms to enable cohesive human groups.

Domain-general mechanisms are evolutionarily ancient, resulting from the evolution of affective cues signaling the attainment of evolutionary goals. Explicit processing is a particularly important set of domain-general mechanisms for constructing human groups - enabling ideologies specifying future goal states and rationalizing group aims, enabling knowledge of others' reputations essential to cooperation, understanding the rights and obligations of group membership, monitoring group members, and providing appropriate punishments to those who deviate from group aims.

Evolving the future by creating and adapting to novel environments.

Adaptation demands effective responses to both recurrent and novel environmental challenges. Developmental plasticity and domain-general mechanisms have important consequences with respect to our human capacity for imagining, creating, and adapting to novel environments. They facilitate the evolution of any cognitive mechanism, no matter how opportunistic, flexible, or domain-general, that is able to solve new problems or achieve new goals.

Mind what you say-general and specific mechanisms for monitoring in speech production.

For most people, speech production is relatively effortless and error-free. Yet it has long been recognized that we need some type of control over what we are currently saying and what we plan to say. Precisely how we monitor our internal and external speech has been a topic of research interest for several decades. The predominant approach in psycholinguistics has assumed monitoring of both is accomplished via systems responsible for comprehending others' speech. This special topic aimed to broaden the field, firstly by examining proposals that speech production might also engage more general systems, such as those involved in action monitoring. A second aim was to examine proposals for a production-specific, internal monitor. Both aims require that we also specify the nature of the representations subject to monitoring. Domain general mechanisms Some of the first evidence to support a proposal of a domain general monitoring or attentional selection mechanism being engaged in speech production was provided by functional magnetic resonance imaging (fMRI) investigations of semantic interference effects in picture-naming paradigms. Those studies identified differential activity in the anterior cingulate cortex (ACC), noting similar activity had been observed in fMRI studies of picture-word (PWI), Stroop and manual interference paradigms (e.g., de Zubicaray et al., 2006). Piai et al. (2013) provide the first confirmatory evidence of a domain general, ACC involvement during performance of Stroop, semantic PWI and manual Simon tasks. Although PWI might be considered a generalization of Stroop-like interference effects (e.g., MacLeod, 1991), the Simon task elicits an interference effect in manual responding by manipulating the spatial location of target stimuli (e.g., a square or triangle) on congruent and incongruent trials. Thus, any overlap in ACC activity across the three tasks can be interpreted as reflecting a domain general mechanism. Electrophysiological studies provide another source of evidence for a domain general fronto-central monitoring mechanism via both stimulus- and response-locked analyses (Ries et al., 2013; Trewartha and Phillips, 2013; Acheson and Hagoort, 2014). Using a phoneme substitution task, Trewartha and Phillips (2013) report an error-related negative potential (ERN) similar to that observed for manual actions. They conclude that speech errors are detected by a general conflict monitoring mechanism supported by the ACC. However, Acheson and Hagoort (2014) tested the domain generality assumption by directly comparing event-related potentials (ERPs) on tongue twister (TT) and Flanker tasks. The TT task required participants to repeatedly and rapidly read sequences of regular non-words. Despite observing similar ERNs, Acheson and Hagoort observed few correlations between behavioral or electrophysiological measures from the two tasks. Together, the results from the above studies suggest that competition among lexical-level representations might engage a domain general mechanism in the ACC, while conflicting sub-lexical (i.e., phoneme) level representations might engage a different mechanism, either in another subdivision of the ACC or elsewhere in superior medial frontal cortex. The working memory requirements of production paradigms might also be crucial for the engagement of domain general mechanisms. Ries et al. (2013) address this issue in patients with lesions of the lateral prefrontal cortex (DLPFC), with results indicating that picture naming might not require mechanisms mediated by this region, unless working memory load is increased, as per the verbal Simon task they employed. Crowther and Martin (2014) demonstrate that working memory is clearly involved in more complex production paradigms that manipulate both semantic context and item repetition, such as blocked cyclic naming, finding significant correlations with verbal memory span. In addition, they report the decreasing slope of naming latencies within cycles derives from a process of narrowing down available responses from the set of items within the block as the trials progress. This indicates participants monitor the item names they produce in order to perform the task. Further, they argue this reflects a strategic, task-specific process rather than a mechanism involved in word production in more naturalistic settings. Intriguingly, Ries et al.'s and Crowther and Martin's converging conclusions regarding the involvement of working memory in production are supported by a recent study by Wirth et al. (2011). The latter authors employed anodal transcranial direct current stimulation (atDCS), an electrical brain stimulation technique that induces more efficient neural processing at the stimulation site. They reported aTDCS applied over the left DLPFC reduced the semantic interference effect observed in the blocked cyclic naming paradigm.