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

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

Short-Term Memory Improvement After Simultaneous Interpretation Training

open4siSimultaneous interpretation (SI) is a cognitively demanding process that has been associated with enhanced memory and executive functions. It is unclear, however, if the previously evidenced interpreter advantages are developed through training and/or experience with SI or rather represent inherent characteristics that allow success in the field. The present study aimed to disentangle these possibilities through a longitudinal examination of students earning a Master of Conference Interpreting and two control populations. The students were tested at the beginning and end of their programs on measures of memory and executive functioning that have previously demonstrated an interpreter advantage. The results revealed no inherent advantage among the students of interpretation. However, an SI training-specific advantage was revealed in verbal short-term memory; the students of interpretation, but not the two control groups, showed a gain between the testing sessions. This controlled longitudinal study demonstrates that training in simultaneous interpretation is associated with cognitive changes.openBabcock, Laura; Capizzi, Mariagrazia; Arbula, Sandra; Vallesi, AntoninoBabcock, Laura; Capizzi, Mariagrazia; Arbula, Sandra; Vallesi, Antonin

Testing the domain-general nature of monitoring in the spatial and verbal cognitive domains

While it is well-established that monitoring the environment for the occurrence of relevant events represents a key executive function, it is still unclear whether such a function is mediated by domain-general or domain-specific mechanisms. We investigated this issue by combining event-related potentials (ERPs) with a behavioral paradigm in which monitoring processes (non-monitoring vs. monitoring) and cognitive domains (spatial vs. verbal) were orthogonally manipulated in the same group of participants. They had to categorize 3-dimensional visually presented words on the basis of either spatial or verbal rules. In monitoring blocks, they additionally had to check whether the word displayed a specific spatial configuration or whether it contained a certain consonant. The behavioral results showed slower responses for both spatial and verbal monitoring trials compared to non-monitoring trials. The ERP results revealed that monitoring did not interact with domain, thus suggesting the involvement of common underlying mechanisms. Specifically, monitoring acted on lower-level perceptual processes (as expressed by an enhanced visual N1 wave and a sustained posterior negativity for monitoring trials) and on higher-level cognitive processes (involving larger positive modulations by monitoring trials over frontal and parietal scalp regions). The source reconstruction analysis of the ERP data confirmed that monitoring was associated with increased activity in visual areas and in right prefrontal and parietal regions (i.e., superior and inferior frontal gyri and posterior parietal cortex), which previous studies have linked to spatial and temporal monitoring. Our findings extend this research by supporting the domain-general nature of monitoring in the spatial and verbal domains

Electrophysiological evidence for domain-general processes in task-switching

open5noopenCapizzi, Mariagrazia; Ambrosini, Ettore; Arbula, Sandra; Mazzonetto, Ilaria; Vallesi, AntoninoCapizzi, Mariagrazia; Ambrosini, Ettore; Arbula, Sandra; Mazzonetto, Ilaria; Vallesi, Antonin

Tracing the boundaries of executive function fractionation: evidence from lesion-symptom mapping in brain tumor patients

The purpose of the present research project was to investigate, by means of different lesion-symptom mapping techniques, the behavioral consequences of focal frontal lobe injuries in order to tackle the currently debated issues regarding the PFC organization. In particular, in the first two studies we aimed at delineating the observed impairments as possible disruptions of common and/or distinct processes in order to test the dissociability of putatively distinct cognitive control processes. We focused on switching and response inhibition abilities, which according to the literature rely on left and right prefrontal areas, and tested whether their impairments could be accounted for by more general task-setting and/or sustained attention impairments. In particular, we tested brain tumor patients with left and right prefrontal damage, and compared their performance with non-prefrontal patients and healthy controls. Critically, in order to exclude eventual lower-level processing difficulties known to emerge after lateralized brain lesions, verbal and spatial features of the employed tasks were mostly balanced. The results from both studies suggest that there is probably no specialized inhibitory or switching module hosted by a particular brain area; instead they show how performance on tasks requiring both inhibitory and switching abilities can be disrupted by a more general task-setting impairment supported by left prefrontal areas and their connections with posterior regions. Furthermore, inhibitory impairments, previously observed in patients with right prefrontal lesion, might alternatively be explained by sustained attention impairments. In the last study, instead, we focused on finding out whether lesions in specific prefrontal areas could account for a general cognitive decline, as supported by unitary models of the PFC organization. In particular, we applied a latent variable analysis on distinct neuropsychological test scores in order to minimize the influence of low-level processing requirements and thus obtain a more pure measure of general cognitive functioning. Additionally, we examined the impact of surgical tumor removal on general cognitive functioning across different tumor histological types. The results confirmed previous findings on the impact of surgery on low-grade glioma. However, they also extend them by showing that surgery in left dorsolateral frontal areas causes a more prominent cognitive decline, regardless of the tumor histology. Taken together, the findings across all the three studies have highlighted a critical involvement of left- lateralized prefrontal areas in most of the high-level cognitive tasks we employed, event though the precise localization was somewhat different. However, the involvement of right prefrontal areas seemed critical in more sustained type of processing required to maintain attention to task-relevant events. This observation is in line with a more integrative, albeit lateralized, view of the PFC organization according to which higher, associative types of processes rely on the interaction between frontal and posterior brain regions, but their left and right lateralizations reflect separate, specialized type of processing probably involved in more phasic type of processing, necessary to form and flexibly implement task-relevant associations, and sustained type of processing, needed to maintain the relevant features of the task in an active state

Domain-independent neural underpinning of task-switching: an fMRI investigation

The ability to shift between different tasks according to internal or external demands, which is at the core of our behavioral flexibility, has been generally linked to the functionality of left fronto-parietal regions. Traditionally, the left and right hemispheres have also been associated with verbal and spatial processing, respectively. We therefore investigated with functional MRI whether the processes engaged during task-switching interact in the brain with the domain of the tasks to be switched, that is, verbal or spatial. Importantly, physical stimuli were exactly the same and participants\u2019 performance was matched between the two domains. The fMRI results showed a clearly left-lateralized involvement of fronto-parietal regions when contrasting task-switching vs. single task blocks in the context of verbal rules. A more bilateral pattern, especially in the prefrontal cortex, was instead observed for switching between spatial tasks. Moreover, while a conjunction analysis showed that the core regions involved in task-switching, independently of the switching context, were localized both in left inferior prefrontal and parietal cortices and in bilateral supplementary motor area, a direct analysis of functional lateralization revealed that hemispheric asymmetries in the frontal lobes were more biased toward the left side for the verbal domain than for the spatial one and vice versa. Overall, these findings highlight the role of left fronto-parietal regions in task-switching, above and beyond the specific task requirements, but also show that hemispheric asymmetries may be modulated by the more specific nature of the tasks to be performed during task-switching

Neuro-cognitive architecture of executive functions: A latent variable analysis

Executive functions refer to high-level cognitive processes that, by operating on lower-level mental processes, flexibly regulate and control our thoughts and goal-directed behavior. Despite their crucial role, the study of the nature and organization of executive functions still faces inherent difficulties. Moreover, most executive function models put under test until now are brain-free models: they are defined and discussed without assumptions regarding the neural bases of executive functions. By using a latent variable approach, here we tested a brain-centered model of executive function organization proposing that two distinct domain-general executive functions, namely, criterion setting and monitoring, may be dissociable both functionally and anatomically, with a left vs. right hemispheric preference of prefrontal cortex and related neural networks, respectively. To this end, we tested a sample of healthy participants on a battery of computerized tasks assessing criterion setting and monitoring processes and involving diverse task domains, including the verbal and visuospatial ones, which are well-known to be lateralized. By doing this, we were able to specifically assess the influence of these task domains on the organization of executive functions and to directly contrast a process-based model of EF organization versus both a purely domain-based model and a process-based, but domain-dependent one. The results of confirmatory factor analyses showed that a purely process-based model reliably provided a better fit to the observed data as compared to alternative models, supporting the specific theoretical model that fractionates a subset of executive functions into criterion setting and monitoring with hemispheric specializations emerging regardless of the task domain

TMS on Prefrontal Cortex Influences Temporal Orienting but not Preparation Guided by Rhythms

AbstractA neuropsychological study suggested a role for the right prefrontal cortex in temporal orienting of attention and the left prefrontal cortex in preparation guided by rhythms (Triviño et al., 2011). We tested this hypothesis by comparing the effects of transcranial magnetic stimulation (TMS) on the performances of two temporal preparation tasks, one using symbolic cues (short vs. long lines) and the other using regular rhythms (with fast vs. slow pace) to indicate when a target was most likely to appear. Stimulation site was either the left dorsolateral prefrontal cortex (l-DLPFC), right DLPFC, or sham condition. The results showed that frontal TMS produced differential effects as a function of type of cuing. In symbolic cuing, TMS on either left or right frontal sites (vs. sham) increased validity effects by reducing reaction times in valid trials. In rhythmic cuing, however, frontal TMS did not influence performance. These findings: 1) dissociated between temporal preparation guided by cues vs. rhythms, 2) suggest a role of bilateral DLPFC (and inhibitory processes) in the ability for temporal orienting, and 3) confirmed the automatic nature of temporal regularity, which is more robust to interference than temporal orienting

Addressing the selective role of distinct prefrontal areas in response suppression: A study with brain tumor patients

The diverging evidence for functional localization of response inhibition within the prefrontal cortex might be justified by the still unclear involvement of other intrinsically related cognitive processes like response selection and sustained attention. In this study, the main aim was to understand whether inhibitory impairments, previously found in patients with both left and right frontal lesions, could be better accounted for by assessing these potentially related cognitive processes. We tested 37 brain tumor patients with left prefrontal, right prefrontal and non-prefrontal lesions and a healthy control group on Go/No-Go and Foreperiod tasks. In both types of tasks inhibitory impairments are likely to cause false alarms, although additionally the former task requires response selection and the latter target detection abilities. Irrespective of the task context, patients with right prefrontal damage showed frequent Go and target omissions, probably due to sustained attention lapses. Left prefrontal patients, on the other hand, showed both Go and target omissions and high false alarm rates to No-Go and warning stimuli, suggesting a decisional rather than an inhibitory impairment. An exploratory whole-brain voxel-based lesion-symptom mapping analysis confirmed the association of left ventrolateral and dorsolateral prefrontal lesions with target discrimination failure, and right ventrolateral and medial prefrontal lesions with target detection failure. Results from this study show how left and right prefrontal areas, which previous research has linked to response inhibition, underlie broader cognitive control processes, particularly involved in response selection and target detection. Based on these findings, we suggest that successful inhibitory control relies on more than one functionally distinct process which, if assessed appropriately, might help us to better understand inhibitory impairments across different pathologies

Tracing the boundaries of executive function fractionation: evidence from lesion-symptom mapping in brain tumor patients

The purpose of the present research project was to investigate, by means of different lesion-symptom mapping techniques, the behavioral consequences of focal frontal lobe injuries in order to tackle the currently debated issues regarding the PFC organization. In particular, in the first two studies we aimed at delineating the observed impairments as possible disruptions of common and/or distinct processes in order to test the dissociability of putatively distinct cognitive control processes. We focused on switching and response inhibition abilities, which according to the literature rely on left and right prefrontal areas, and tested whether their impairments could be accounted for by more general task-setting and/or sustained attention impairments. In particular, we tested brain tumor patients with left and right prefrontal damage, and compared their performance with non-prefrontal patients and healthy controls. Critically, in order to exclude eventual lower-level processing difficulties known to emerge after lateralized brain lesions, verbal and spatial features of the employed tasks were mostly balanced. The results from both studies suggest that there is probably no specialized inhibitory or switching module hosted by a particular brain area; instead they show how performance on tasks requiring both inhibitory and switching abilities can be disrupted by a more general task-setting impairment supported by left prefrontal areas and their connections with posterior regions. Furthermore, inhibitory impairments, previously observed in patients with right prefrontal lesion, might alternatively be explained by sustained attention impairments. In the last study, instead, we focused on finding out whether lesions in specific prefrontal areas could account for a general cognitive decline, as supported by unitary models of the PFC organization. In particular, we applied a latent variable analysis on distinct neuropsychological test scores in order to minimize the influence of low-level processing requirements and thus obtain a more pure measure of general cognitive functioning. Additionally, we examined the impact of surgical tumor removal on general cognitive functioning across different tumor histological types. The results confirmed previous findings on the impact of surgery on low-grade glioma. However, they also extend them by showing that surgery in left dorsolateral frontal areas causes a more prominent cognitive decline, regardless of the tumor histology. Taken together, the findings across all the three studies have highlighted a critical involvement of left- lateralized prefrontal areas in most of the high-level cognitive tasks we employed, event though the precise localization was somewhat different. However, the involvement of right prefrontal areas seemed critical in more sustained type of processing required to maintain attention to task-relevant events. This observation is in line with a more integrative, albeit lateralized, view of the PFC organization according to which higher, associative types of processes rely on the interaction between frontal and posterior brain regions, but their left and right lateralizations reflect separate, specialized type of processing probably involved in more phasic type of processing, necessary to form and flexibly implement task-relevant associations, and sustained type of processing, needed to maintain the relevant features of the task in an active state.L’attuale progetto di ricerca è volto ad indagare le funzioni specifiche della corteccia prefrontale e la loro localizzazione mediante studi neuropsicologici su pazienti con tumore al cervello. Nei primi due studi ci siamo focalizzati sui processi di inibizione e di switching che, in base alla letteratura, vengono sostenuti da aree nella corteccia prefrontale a destra e sinistra, rispettivamente. In particolare, testando pazienti con lesioni in queste aree, assieme ad altri con lesioni non frontali e soggetti sani, abbiamo cercato di disambiguare se i deficit osservati in questi pazienti possono venir spiegati meglio da danni ad altri processi di controllo cognitivo più generali, come il monitoring e il task-setting, per i quali diversi studi nei sani hanno dimostrato la lateralizzazione opposta nella corteccia prefrontale. I risultati di questi primi due studi suggeriscono che sia il controllo inibitorio che di switching possono venir compromessi da un deficit più generale di task-setting dovuto a lesioni prefrontali a sinistra. Inoltre, difficoltà inibitorie precedentemente osservate nei pazienti con lesioni prefrontali a destra sembrano essere dovute a un deficit più generale di monitoring. Nell’ultimo studio invece abbiamo indagato se le lesioni in aree prefrontali possono sottostare a un declino cognitivo generale, come suggerito da modelli unitari dell’organizzazione della corteccia prefrontale. In particolare, per ottenere una misura più pulita dello status cognitivo generale, abbiamo estrapolato mediante la Principal Component Analysis una componente che spiega la varianza comune nei diversi test neuropsicologici e l’abbiamo confrontata tra i diversi gruppi di pazienti divisi per il tipo di tumore (alto grado, basso grado, meningioma, metastasi) e le diverse aree lesionate. I risultati hanno confermato studi precedenti che trovano un maggiore declino generale dopo la chirurgia nei pazienti con tumore a basso grado. Tuttavia, abbiamo osservato che il declino maggiore è dovuto inoltre a lesioni in aree dorsolaterali della corteccia prefrontale a sinistra, indipendentemente dal tipo di tumore. I risultati di questi tre studi supportano una visione più integrativa, sebbene lateralizzata dell’organizzazione funzionale della corteccia prefrontale