207 research outputs found

    Monitoring Processes in Visual Search Enhanced by Professional Experience: The Case of Orange Quality-Control Workers

    Get PDF
    Visual search tasks have often been used to investigate how cognitive processes change with expertise. Several studies have shown visual experts' advantages in detecting objects related to their expertise. Here, we tried to extend these findings by investigating whether professional search experience could boost top-down monitoring processes involved in visual search, independently of advantages specific to objects of expertise. To this aim, we recruited a group of quality-control workers employed in citrus farms. Given the specific features of this type of job, we expected that the extensive employment of monitoring mechanisms during orange selection could enhance these mechanisms even in search situations in which orange-related expertise is not suitable. To test this hypothesis, we compared performance of our experimental group and of a well-matched control group on a computerized visual search task. In one block the target was an orange (expertise target) while in the other block the target was a Smurfette doll (neutral target). The a priori hypothesis was to find an advantage for quality-controllers in those situations in which monitoring was especially involved, that is, when deciding the presence/absence of the target required a more extensive inspection of the search array. Results were consistent with our hypothesis. Quality-controllers were faster in those conditions that extensively required monitoring processes, specifically, the Smurfette-present and both target-absent conditions. No differences emerged in the orange-present condition, which resulted to mainly rely on bottom-up processes. These results suggest that top-down processes in visual search can be enhanced through immersive real-life experience beyond visual expertise advantages

    Spatiotemporally dissociable neural signatures for generating and updating expectation over time in children: A High Density-ERP study

    Get PDF
    Temporal orienting (TO) is the allocation of attentional resources in time based on the a priori generation of temporal expectancy of relevant stimuli as well as the a posteriori updating of this expectancy as a function of both sensory-based evidence and elapsing time. These processes rely on dissociable cognitive mechanisms and neural networks. Yet, although there is evidence that TO may be a core mechanism for cognitive functioning in childhood, the developmental spatiotemporal neural dynamics of this mechanism are little understood. In this study we employed a combined approach based on the application of distributed source reconstruction on a high spatial resolution ERP data array obtained from eighteen 8- to 12-year-old children completing a TO paradigm in which both the cue (Temporal vs. Neutral) and the SOA (Short vs. Long) were manipulated. Results show both cue (N1) and SOA (CNV, Omission Detection Potential and Anterior Anticipatory Index) ERP effects, which were associated with expectancy generation and updating, respectively. Only cue-related effects were correlated with age, as revealed by a reduction of the N1 delta effect with increasing age. Our data suggest that the neural correlates underlying TO are already established at least from 8 to 12 years of age

    Domain-general Stroop Performance and Hemispheric Asymmetries: A Resting-state EEG Study

    Get PDF
    The ability to suppress irrelevant information while executing a task or interference resistance is a function of pFC that is critical for successful goal-directed human behavior. In the study of interference resistance and, more generally, executive functions, two key questions are still open: Does pFC contribute to cognitive control abilities through lateralized but domain-general mechanisms or through hemispheric specialization of domain-specific processes? And what are the underlying causes of interindividual differences in executive control performance? To shed light on these issues, here we employed an interindividual difference approach to investigate whether participants' hemispheric asymmetry in resting-state electrophysiological brain dynamics may reflect their variability in domain-general interference resistance. We recorded participants' resting-state electroencephalographic activity and performed spectral power analyses on the estimated cortical source activity. To measure participants' lateralized brain dynamics at rest, we computed the right-left hemispheric asymmetry score for the \u3b2/\u3b1 power ratio. To measure their domain-general interference resistance ability, verbal and spatial Stroop tasks were used. Robust correlations followed by intersection analyses showed that participants with stronger resting-state-related left-lateralized activity in different pFC regions, namely the mid-posterior superior frontal gyrus, middle and posterior middle frontal gyrus, and inferior frontal junction, were more able to inhibit irrelevant information in both domains. The present results confirm and extend previous findings showing that neurophysiological difference factors may explain interindividual differences in executive functioning. They also provide support for the hypothesis of a left pFC hemispheric specialization for domain-independent phasic cognitive control processes mediating Stroop performance

    Language control is not a one-size-fits-all languages process: Evidence from simultaneous interpretation students and the n-2 repetition cost

    Get PDF
    Simultaneous interpretation is an impressive cognitive feat which necessitates the simultaneous use of two languages and therefore begs the question: how is language management accomplished during interpretation? One possibility is that both languages are maintained active and inhibitory control is reduced. To examine whether inhibitory control is reduced after experience with interpretation, students with varying experience were assessed on a three language switching paradigm. This paradigm provides an empirical measure of the inhibition applied to abandoned languages, the n-2 repetition cost. The groups showed different patterns of n-2 repetition costs across the three languages. These differences, however, were not connected to experience with interpretation. Instead, they may be due to other language characteristics. Specifically, the L2 n-2 repetition cost negatively correlated with self-rated oral L2 proficiency, suggesting that language proficiency may affect the use of inhibitory control. The differences seen in the L1 n-2 repetition cost, alternatively, may be due to the differing predominant interactional contexts of the groups. These results suggest that language control may be more complex than previously thought, with different mechanisms used for different languages. Further, these data represent the first use of the n-2 repetition cost as a measure to compare language control between groups

    Are simultaneous interpreters expert bilinguals, unique bilinguals, or both?

    Get PDF
    Simultaneous interpretation is a cognitively demanding process that requires a high level of language management. Previous studies on bilinguals have suggested that extensive practice managing two languages leads to enhancements in cognitive control. Thus, interpreters may be expected to show benefits beyond those seen in bilinguals, either as an extension of previously-seen benefits or in areas specific to interpretation. The present study examined professional interpreters (N = 23) and matched multilinguals (N = 21) on memory tests, the color-word Stroop task, the Attention Network Test, and a non-linguistic task-switching paradigm. The interpreters did not show advantages in conflict resolution or switching cost where bilingual benefits have been noted. However, an interpretation-specific advantage emerged on the mixing cost in the task-switching paradigm. Additionally, the interpreters had larger verbal and spatial memory spans. Interpreters do not continue to garner benefits from bilingualism, but they do appear to possess benefits specific to their experience with simultaneous interpretation

    The interaction of process and domain in prefrontal cortex during inductive reasoning

    Get PDF
    AbstractInductive reasoning is an everyday process that allows us to make sense of the world by creating rules from a series of instances. Consistent with accounts of process-based fractionations of the prefrontal cortex (PFC) along the left–right axis, inductive reasoning has been reliably localized to left PFC. However, these results may be confounded by the task domain, which is typically verbal. Indeed, some studies show that right PFC activation is seen with spatial tasks. This study used fMRI to examine the effects of process and domain on the brain regions recruited during a novel pattern discovery task. Twenty healthy young adult participants were asked to discover the rule underlying the presentation of a series of letters in varied spatial locations. The rules were either verbal (pertaining to a single semantic category) or spatial (geometric figures). Bilateral ventrolateral PFC activations were seen for the spatial domain, while the verbal domain showed only left ventrolateral PFC. A conjunction analysis revealed that the two domains recruited a common region of left ventrolateral PFC. The data support a central role of left PFC in inductive reasoning. Importantly, they also suggest that both process and domain shape the localization of reasoning in the brain

    The monitoring role of right lateral prefrontal cortex: evidence from variable foreperiod and source memory tasks

    Get PDF
    The main purpose of this research project was to investigate the monitoring function of the right dorsolateral prefrontal cortex using different tasks in two domains. To that purpose, the architecture of the cognitive processes required to perform each task was extracted by means of different approaches of functional dissociation. A variable foreperiod (FP) task was initially adopted. In such a task, simple/choice RTs are required while FPs of different duration vary on a trial-by-trial basis equiprobably in a rectangular distribution but randomly. As a result, the conditional probability is higher later in the FP range and RT is faster as the FP increases. This is the variable FP effect, which a recent neuropsychological study shows to be impaired in right lateral prefrontal patients. Another phenomenon usually obtained with such a paradigm is that of the sequential effects: RT becomes slower as the FP on the preceding trial gets longer. Contrasting views in the literature propose either multi-process strategic accounts, or a single-process conditioning account. In the project, these alternative theories were tested using behavioural studies on adults and children. The findings of these studies were not fully compatible with the previous views. A composite dual-process account, which shares some aspects with the previous accounts, was put forward and discussed. On this account, sequential effects are due to automatic processes acting on the arousal level, whereas the FP effect is due to a strategic process monitoring the conditional probability of stimulus occurrence. Results of two TMS experiments confirm that the right dorsolateral prefrontal cortex is responsible for the FP effect, but not for the sequential effects. A neuropsychological study on tumor patients further corroborates this finding and suggests that left premotor areas are more likely to be the locus of the sequential effects. In order to test whether the explicit temporal judgment has an influence on the nature of the FP phenomena, a series of behavioural experiments was conducted using a modified version of the variable FP paradigm. In the basic task, explicit judgments about the FP length were required. No modulation of the FP phenomena was obtained. However, a new stimulus-response compatibility effect was found: RT was faster when short and long FPs had to be responded to with left and right response-keys, respectively, than with the opposite stimulus-response mapping. This effect suggests that elapsing time is represented, in some circumstances, by means of spatial coordinates. Control experiments enable us to reject accounts based on hand/hemispheric asymmetries, but not accounts based on more categorical factors such as the linguistic markedness of the words used to label the stimuli and the responses. The last part of the project aimed at extending results about a monitoring role (intended in a broad sense) of the right prefrontal cortex to a domain different from non-specific preparation. Two experiments in the source memory domain were run recording ERPs in the retrieval phase. The results show that prefrontal ERPs are not modulated by retrieval success, but by retrieval confidence, with low-confidence responses being associated with more positive waves than high-confidence ones, bilaterally, in the anterior prefrontal sites. Moreover, prefrontal waves were asymmetrically more positive in the right than in the left scalp regions, independently of confidence and accuracy. On the basis of these results, we could reject accounts linked to retrieval success. The results are instead interpreted in terms of different prefrontally-located monitoring processes in source memory retrieval. Overall, the project represents an instantiation of the fractionation approach recently adopted to study the supervisory functions of the prefrontal cortex. This approach was used here in order to understand the differential role of a particular prefrontal area (i.e., the right dorsolateral prefrontal cortex) in a rather specific function (i.e., monitoring). This goal was developed in synchrony with the attainment of a better functional description of the tasks employed

    Speed-accuracy strategy regulations in prefrontal tumor patients

    Get PDF
    The ability to flexibly switch between fast and accurate decisions is crucial in everyday life. Recent neuroimaging evidence suggested that left lateral prefrontal cortex plays a role in switching from a quick response strategy to an accurate one. However, the causal role of the left prefrontal cortex in this particular, non-verbal, strategy switch has never been demonstrated. To fill this gap, we administered a perceptual decision-making task to neuro-oncological prefrontal patients, in which the requirement to be quick or accurate changed randomly on a trial-by-trial basis. To directly assess hemispheric asymmetries in speed-accuracy regulation, patients were tested a few days before and a few days after surgical excision of a brain tumor involving either the left (N=13) or the right (N=12) lateral frontal brain region. A group of age- and education-matched healthy controls was also recruited. To gain more insight on the component processes implied in the task, performance data (accuracy and speed) were not only analyzed separately but also submitted to a diffusion model analysis. The main findings indicated that the left prefrontal patients were impaired in appropriately adopting stricter response criteria in speed-to-accuracy switching trials with respect to healthy controls and right prefrontal patients, who were not impaired in this condition. This study demonstrates that the prefrontal cortex in the left hemisphere is necessary for flexible behavioral regulations, in particular when setting stricter response criteria is required in order to successfully switch from a speedy strategy to an accurate one

    How Life Experience Shapes Cognitive Control Strategies: The Case of Air Traffic Control Training

    Get PDF
    Although human flexible behavior relies on cognitive control, it would be implausible to assume that there is only one, general mode of cognitive control strategy adopted by all individuals. For instance, different reliance on proactive versus reactive control strategies could explain inter-individual variability. In particular, specific life experiences, like a highly demanding training for future Air Traffic Controllers (ATCs), could modulate cognitive control functions. A group of ATC trainees and a matched group of university students were tested longitudinally on task-switching and Stroop paradigms that allowed us to measure indices of cognitive control. The results showed that the ATCs, with respect to the control group, had substantially smaller mixing costs during long cue-target intervals (CTI) and a reduced Stroop interference effect. However, this advantage was present also prior to the training phase. Being more capable in managing multiple task sets and less distracted by interfering events suggests a more efficient selection and maintenance of task relevant information as an inherent characteristic of the ATC group, associated with proactive control. Critically, the training that the ATCs underwent improved their accuracy in general and reduced response time switching costs during short CTIs only. These results indicate a training-induced change in reactive control, which is described as a transient process in charge of stimulus-driven task detection and resolution. This experience-based enhancement of reactive control strategy denotes how cognitive control and executive functions in general can be shaped by real-life training and underlines the importance of experience in explaining inter-individual variability in cognitive functioning
    • …
    corecore