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During task executions, brain activity increases in executive networks (ENs) and decreases in default-mode networks (DMNs). Here, we examined whether these large-scale network dynamics can be influenced by unconscious cognitive information processing. Volunteers saw instructions (cues) to respond either ipsilaterally or contralaterally to a subsequent lateralized target. Unbeknownst to them, each cue was preceded by a masked stimulus (prime), which could be identical (congruent), or opposite (incongruent) to the cue, or neutral (not an instruction). Behaviorally, incongruent primes interfered with performance, even though they were not consciously perceived. With functional magnetic resonance imaging, we individuated the anticorrelated ENs and DMNs involved during task execution. With effective connectivity analyses, we found that DMNs caused activity in ENs throughout the task. Unconscious interference during incongruent trials was associated with a specific activity increase in ENs and an activity drop in DMNs. Intersubject efficiency in performance during incongruent trials was correlated with functional connectivity between specific ENs and DMNs. These results indicate that unconscious instructions can prime activity in ENs and DMNs and suggest that the DMNs play a key role in unconscious monitoring of the environment in the service of efficient resource allocation for task execution., Psychology

Digital communication technologies are rapidly evolving, and understanding their impact on group dynamics and cognitive performance in professional settings becomes central. This study investigates the psychological impact of different interaction settings-two-dimensional Video Conferencing (VC), Face-To-Face (FTF), and Virtual Reality (VR)-on group dynamics, cognitive performance, and aspects of well-being in a professional context. Utilizing a sample of 40 participants from a large Italian electricity transmission company, the study employs a within-subjects design to explore various metrics, including flow, creativity, fatigue and aspects of interaction. The results indicate that FTF interactions are optimal for idea generation and task absorption. VR, although initially more fatiguing for first-time users, fosters a more collaborative and peaceful environment, encouraging participants to engage more openly with each other. VC was found to be the least fatiguing, but also the least engaging in terms of task absorption and idea generation. Additionally, age-related differences were observed, particularly in the perception of motivational and emotional fatigue in the VR setting. The study provides empirical evidence supporting the integration of VR in professional settings for specific types of meetings, while also highlighting the limitations and areas for future research. These findings have implications for organizational well-being, cognitive ergonomics, and the evolving landscape of remote work technologies., (© 2024. The Author(s).)

This study aimed to investigate whether there are structural differences in the brains of professional artists who received formal training in the visual arts and non-artists who did not have any formal training or professional experience in the visual arts, and whether these differences can be used to accurately classify individuals as being an artist or not. Previous research using functional MRI has suggested that general creativity involves a balance between the default mode network and the executive control network. However, it is not known whether there are structural differences between the brains of artists and non-artists. In this study, a machine learning method called Multi-Kernel Learning (MKL) was applied to gray matter images of 12 artists and 12 non-artists matched for age and gender. The results showed that the predictive model was able to correctly classify artists from non-artists with an accuracy of 79.17% (AUC 88%), and had the ability to predict new cases with an accuracy of 81.82%. The brain regions most important for this classification were the Heschl area, amygdala, cingulate, thalamus, and parts of the parietal and occipital lobes as well as the temporal pole. These regions may be related to the enhanced emotional and visuospatial abilities that professional artists possess compared to non-artists. Additionally, the reliability of this circuit was assessed using two different classifiers, which confirmed the findings. There was also a trend towards significance between the circuit and a measure of vividness of imagery, further supporting the idea that these brain regions may be related to the imagery abilities involved in the artistic process.

Creative problem solving is a fundamental skill of human cognition and is conceived as a search process whereby a novel and appropriate solution is generated. However, it is unclear whether children are able to balance novelty and appropriateness to generate creative solutions and what are the underlying computational mechanisms. Here, we asked children, ranging from 10 to 11 years old, to perform a word association task according to three instructions, which triggered a more appropriate (ordinary), novel (random), or balanced (creative) response. Results revealed that children exhibited greater cognitive flexibility in the creative condition compared to the control conditions, as revealed by the structure and resiliency of the semantic networks. Moreover, responses' word embeddings extracted from pretrained deep neural networks showed that semantic distance and category switching index increased in the creative condition with respect to the ordinary condition and decreased compared to the random condition. Critically, we showed how children efficiently solved the exploration/exploitation trade-off to generate creative associations by fitting a computational reinforcement learning (RL) model that simulates semantic search strategies. Our findings provide compelling evidence that children balance novelty and appropriateness to generate creative associations by optimally regulating the level of exploration in the semantic search. This corroborates previous findings on the adult population and highlights the crucial contribution of both components to the overall creative process. In conclusion, these results shed light on the connections between theoretical concepts such as bottom-up/top-down modes of thinking in creativity research and the exploration/exploitation trade-off in human RL research., (© The Author(s) 2022. Published by Oxford University Press on behalf of National Academy of Sciences.)

Hypnosis and meditation share phenomenological and neurophysiological features, and their comparison is a topic of growing interest in the scientific literature. In this article, we review a classification of these two kinds of non-ordinary states of consciousness, and discuss the studies that directly compare them. Some findings seem to suggest that hypnosis and meditation are distinct phenomena, while others underline their similarities, but experiments that directly contrast them are still scarce and no consensus has been reached yet. While this comparison could give us fundamental insights into central issues concerning the role of attention, metacognition and executive control in the study of consciousness, it is clear that we are still at the early stages of this research., (Copyright © 2022 Penazzi and De Pisapia.)

Examination of conscience (EC) is a contemplative practice that consists in examining daily the actions performed during the day (evening examination, immediately before going to bed) and the actions to be performed on the coming day (morning examination, immediately after sleep). While research on contemplative practices such as mindfulness has seen a large increase of studies in recent years, research into the psychological effects related to the practice of the EC has been largely ignored in the scientific literature. On the other hand, on a careful historical and philosophical analysis, it appears evident that references to it abound in many cultural contexts and in different eras. Here, we examined the effects of a 2-week program of this practice that participants performed using a digital application developed ad hoc for this experiment. A control group performed an activity of the same duration, also with the support of a digital application, but which consisted of listening to audio excerpts of an Italian literary novel. Measurements taken from both groups before and after the 2-week period consisted of self-assessments of metamemory capacity, that is, awareness and knowledge of their own memory processes. Results showed that participants reported a significant decrease in two properties of their metamemory after training, specifically vividness and coherence. No other significant changes were found between the two groups. Specifically, we found no differences in other metamemory characteristics, no differences in prospective or retrospective memory, and no differences in changes in stress levels. These results, although preliminary, suggest that a relatively short period of EC does indeed make people metacognitively more aware of the limitations and errors of their memory, in particular concerning vividness and coherence., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 De Pisapia and Dall’Avanzi.)

Historically, psychedelic drugs are known to modulate cognitive flexibility, a central aspect of cognition permitting adaptation to changing environmental demands. Despite proof suggesting phenomenological similarities between artificially-induced and actual psychedelic altered perception, experimental evidence is still lacking about whether the former is also able to modulate cognitive flexibility. To address this, we measure participants' cognitive flexibility through behavioral tasks after the exposure to virtual reality panoramic videos and their hallucinatory-like counterparts generated by the DeepDream algorithm. Results show that the estimated semantic network has a flexible structure when preceded by altered videos. Crucially, following the simulated psychedelic exposure, individuals also show an attenuated contribution of the automatic process and chaotic dynamics underlying the decision process. This suggests that simulated altered perceptual phenomenology enhances cognitive flexibility, presumably due to a reorganization in the cognitive dynamics that facilitates the exploration of uncommon decision strategies and inhibits automated choices., (© 2022. The Author(s).)

In recent decades, psychological research on the effects of mindfulness-based interventions has greatly developed and demonstrated a range of beneficial outcomes in a variety of populations and contexts. Yet, the question of how to foster subjective well-being and happiness remains open. Here, we assessed the effectiveness of an integrated mental training program The Art of Happiness on psychological well-being in a general population. The mental training program was designed to help practitioners develop new ways to nurture their own happiness. This was achieved by seven modules aimed at cultivating positive cognition strategies and behaviors using both formal (i.e., lectures, meditations) and informal practices (i.e., open discussions). The program was conducted over a period of 9 months, also comprising two retreats, one in the middle and one at the end of the course. By using a set of established psychometric tools, we assessed the effects of such a mental training program on several psychological well-being dimensions, taking into account both the longitudinal effects of the course and the short-term effects arising from the intensive retreat experiences. The results showed that several psychological well-being measures gradually increased within participants from the beginning to the end of the course. This was especially true for life satisfaction, self-awareness, and emotional regulation, highlighting both short-term and longitudinal effects of the program. In conclusion, these findings suggest the potential of the mental training program, such as The Art of Happiness , for psychological well-being., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Rastelli, Calabrese, Miller, Raffone and De Pisapia.)

Anxiety is a mental state characterized by an intense sense of tension, worry or apprehension, relative to something adverse that might happen in the future. Researchers differentiate aspects of anxiety into state and trait, respectively defined as a more transient reaction to an adverse situation, and as a more stable personality attribute in experiencing events. It is yet unclear whether brain structural and functional features may distinguish these aspects of anxiety. To study this, we assessed 42 healthy participants with the State-Trait Anxiety Inventory and then investigated with MRI to characterize structural grey matter covariance and resting-state functional connectivity (rs-FC). We found several differences in the structural-functional patterns across anxiety types: (1) trait anxiety was associated to both structural covariance of Default Mode Network (DMN), with an increase in dorsal nodes and a decrease in its ventral part, and to rs-FC of DMN within frontal regions; (2) state anxiety, instead, was widely related to rs-FC of Salience Network and of DMN, specifically in its ventral nodes, but not associated with any structural pattern. In conclusion, our study provides evidence of a neuroanatomical and functional distinction between state and trait anxiety. These neural features may be additional markers in future studies evaluating early diagnosis or treatment effects.

Emotion regulation plays a crucial role in an individual's well-being, as it is known that deficits in regulating emotions can lead to psychological and psychiatric disorders. Cognitive reappraisal is widely considered to be an adaptive and effective emotion-regulation strategy. People are more or less able to apply it, but it is still not clear how reappraisal affects brain structures and the psychological profile of individuals. In our study we thus aimed to explore the impact of applying reappraisal at both the neural and the psychological level. Source-based morphometry (SBM), a whole-brain multivariate method based on the Independent Component Analysis that extracts patterns of covariation of gray matter ("independent networks"), was applied to the MRI images of 37 participants. In order to enrich their psychological profiles, we measured their experienced affectivity (PANAS) and their empathic abilities (IRI). Based on the frequency of applying reappraisal (ERQ), participants were divided into low and high reappraisers (18 vs. 19). An independent source of gray matter emerged as being different between the groups: specifically, low reappraisers showed more gray matter volume concentration in a network including the frontal, temporal, and parietal regions as compared to high reappraisers. At the psychological level, low reappraisers reported a more strongly experienced negative affect, while no difference among reappraisers emerged with regard to empathic abilities. Capitalizing on a multivariate method for structural analysis that is innovative in this field, this study extends previous observations on individual differences in the ability to regulate emotions, and it describes a plausible impact of reappraisal on brain structures and affectivity.

In this study we investigate the neural basis of emotional content in self-referential processing by using a combination of off-line repetitive Transcranial Magnetic Stimulation (rTMS) applied to the medial prefrontal cortex (mPFC) and whole-brain functional Magnetic Resonance Imaging (fMRI).We applied effective or ineffective (sham) 1-Hz rTMS to the mPFC of 14 healthy participants who immediately thereafter underwent fMRI while performing a personality attribution task to self or to others. rTMS produced an increase in the participants' reaction time (≈ 60 msec) when processing negative attributes. The neuroimaging findings indicated the involvement of a network of cortical nodes distant from those at the stimulation site; these distant nodes showed task-specific changes in blood oxygen level-dependent (BOLD) activity after effective TMS. The posterior cingulate cortex seemingly encoded the negative dimension of stimuli, but it did not differentiate between self or other. On the contrary the left angular gyrus and the left anterior temporal cortex showed changes indicating encoding of negative self-directed categorization. The mPFC region did not show effects of rTMS along the self-other dimension, but only along the affective dimension. The results indicate that the mPFC is a pivotal node in a cortical network that supports affective referential reasoning. Therefore, a key function of mPFC seems to be related to the processing of negative attributes. In the other nodes of the network the two dimensions of self-other attribution and affective attribution are partially independent, but largely overlapping with different degrees of local specialization.

This report coordinates assessments of five types of behavioral responses in new mothers to their own infants' cries with neurobiological responses in new mothers to their own infants' cries and in experienced mothers and inexperienced nonmothers to infant cries and other emotional and control sounds. We found that 684 new primipara mothers in 11 countries (Argentina, Belgium, Brazil, Cameroon, France, Kenya, Israel, Italy, Japan, South Korea, and the United States) preferentially responded to their infants' vocalizing distress by picking up and holding and by talking to their infants, as opposed to displaying affection, distracting, or nurturing. Complementary functional magnetic resonance imaging (fMRI) analyses of brain responses to their own infants' cries in 43 new primipara US mothers revealed enhanced activity in concordant brain territories linked to the intention to move and to speak, to process auditory stimulation, and to caregive [supplementary motor area (SMA), inferior frontal regions, superior temporal regions, midbrain, and striatum]. Further, fMRI brain responses to infant cries in 50 Chinese and Italian mothers replicated, extended, and, through parcellation, refined the results. Brains of inexperienced nonmothers activated differently. Culturally common responses to own infant cry coupled with corresponding fMRI findings to own infant and to generic infant cries identified specific, common, and automatic caregiving reactions in mothers to infant vocal expressions of distress and point to their putative neurobiological bases. Candidate behaviors embedded in the nervous systems of human caregivers lie at the intersection of evolutionary biology and developmental cultural psychology., Competing Interests: The authors declare no conflict of interest.

The default mode network (DMN) is a complex dynamic network that is critical for understanding cognitive function. However, whether dynamic topological reconfiguration of the DMN occurs across different brain states, and whether this potential reorganization is associated with prior learning or experience is unclear. To better understand the temporally changing topology of the DMN, we investigated both nodal and global dynamic DMN-topology metrics across different brain states. We found that DMN topology changes over time and those different patterns are associated with different brain states. Further, the nodal and global topological organization can be rebuilt by different brain states. These results indicate that the post-task, resting-state topology of the brain network is dynamically altered as a function of immediately prior cognitive experience, and that these modulated networks are assembled in the subsequent state. Together, these findings suggest that the changing topology of the DMN may play an important role in characterizing brain states.

Adult appropriate responding to salient infant signals is vital to child healthy psychological development. Here we investigated how infant crying, relative to other emotive sounds of infant laughing or adult crying, captures adults' brain resources. In a sample of nulliparous women and men, we investigated the effects of different sounds on cerebral activation of the default mode network (DMN) and reaction times (RTs) while listeners engaged in self-referential decision and syllabic counting tasks, which, respectively, require the activation or deactivation of the DMN. Sounds affect women and men differently. In women, infant crying deactivated the DMN during the self-referential decision task; in men, female adult crying interfered with the DMN during the syllabic counting task. These findings point to different brain processes underlying responsiveness to crying in women and men and show that cerebral activation is modulated by situational contexts in which crying occurs.

Throughout recorded history, and across cultures, humans have made visual art. In recent years, the neural bases of creativity, including artistic creativity, have become a topic of interest. In this study we investigated the neural bases of the visual creative process with both professional artists and a group of control participants. We tested the idea that creativity (planning an artwork) would influence the functional connectivity between regions involved in the default mode network (DMN), implicated in divergent thinking and generating novel ideas, and the executive control network (EN), implicated in evaluating and selecting ideas. We measured functional connectivity with functional Magnetic Resonance Imaging (fMRI) during three different conditions: rest, visual imagery of the alphabet and planning an artwork to be executed immediately after the scanning session. Consistent with our hypothesis, we found stronger connectivity between areas of the DMN and EN during the creative task, and this difference was enhanced in professional artists. These findings suggest that creativity involves an expert balance of two brain networks typically viewed as being in opposition.

Characterization of the default mode network (DMN) as a complex network of functionally interacting dynamic systems has received great interest for the study of DMN neural mechanisms. In particular, understanding the relationship of intrinsic resting-state DMN brain network with cognitive behaviors is an important issue in healthy cognition and mental disorders. However, it is still unclear how DMN functional connectivity links to cognitive behaviors during resting-state. In this study, we hypothesize that static and dynamic DMN nodal topology is associated with upcoming cognitive task performance. We used graph theory analysis in order to understand better the relationship between the DMN functional connectivity and cognitive behavior during resting-state and task performance. Nodal degree of the DMN was calculated as a metric of network topology. We found that the static and dynamic posterior cingulate cortex (PCC) nodal degree within the DMN was associated with task performance (Reaction Time). Our results show that the core node PCC nodal degree within the DMN was significantly correlated with reaction time, which suggests that the PCC plays a key role in supporting cognitive function.

Neuroimaging reveals that infant cries activate parts of the premotor cortical system. To validate this effect in a more direct way, we used event-related transcranial magnetic stimulation (TMS). Here, we investigated the presence and the time course of modulation of motor cortex excitability in young adults who listened to infant cries. Specifically, we recorded motor evoked potentials (MEPs) from the biceps brachii (BB) and interosseus dorsalis primus (ID1) muscles as produced by TMS delivered from 0 to 250 ms after sound onset in six steps of 50 ms in 10 females and 10 males. We observed an excitatory modulation of MEPs at 100 ms from the onset of infant cry specific to females and to the ID1 muscle. We regard this modulation as a response to natural cry sounds because it was attenuated to stimuli increasingly different from natural cry and absent in a separate group of females who listened to non-cry stimuli physically matched to natural infant cries. Furthermore, the 100-ms latency of this response is not compatible with a voluntary reaction to the stimulus but suggests an automatic, bottom-up audiomotor association. The brains of adult females appear to be tuned to respond to infant cries with automatic motor excitation.

The present study investigates associations between security of attachment in the mother-child relationship and patterns of brain connectivity in young adults. We hypothesized that secure attachment would relate to more efficient connectivity in white matter association fibers due to increased myelination. Attachment security was measured in 53 young adults using the Kerns Security Scale; anatomical information was acquired using diffusion tensor imaging. Higher fractional anisotropy, an index of directionality of diffusion, related to security of attachment in four left-hemisphere white matter association fibers (uncinate fasciculus, cingulum, superior longitudinal fasciculus, and inferior fronto-occipital fasciculus). As expected, this result was mainly ascribable to increased myelination, which has been independently associated with attachment security. Security of attachment may have an identifiable biological basis. Our research demonstrates the feasibility of coupling neuroimaging tools with clinical investigation.

One of the consequences of extensive mindfulness practice is a reduction of anxiety and depression, but also a capacity to regulate negative emotions. In this study, we explored four key questions concerning mindfulness training: (1) What are the processes by which mindfulness regulates our emotions? (2) Can mindfulness be applied to social emotions? (3) Does mindfulness training affect emotionally driven behavior towards others? (4) Does mindfulness alter physiological reactivity? To address these questions, we tested, in two experiments, the ability of mindfulness meditators to regulate interpersonal emotions (Experiment 1) and interactive behaviors (Experiment 2) as compared to naïve controls. To better understand the mechanisms by which mindfulness regulates emotions, we asked participants to apply two strategies: a cognitive strategy (mentalizing, a form of reappraisal focused on the intentions of others) and an experiential strategy derived from mindfulness principles (mindful detachment). Both groups were able to regulate interpersonal emotions by means of cognitive (mentalizing) and experiential (mindful detachment) strategies. In Experiment 1, a simple effect of meditation, independent from the implementation of the strategies, resulted in reduced emotional and physiological reactivity, as well as in increased pleasantness for meditators when compared to controls, providing evidence of baseline regulation. In Experiment 2, one visible effect of the strategy was that meditators outperformed controls in the experiential (mindful detachment) but not in the cognitive (mentalize) strategy, showing stronger modulation of their interactive behavior (less punishments) and providing evidence of a strategic behavioral regulation. Based on these results, we suggest that mindfulness can influence interpersonal emotional reactions through an experiential mechanism, both at a baseline level and a strategic level, thereby altering the subjective and physiological perception of emotions, but also biasing interactive social behavior.

The right hemisphere of the human brain is known to be involved in processes underlying emotion and social cognition. Clinical neuropsychology investigations and brain lesion studies have linked a number of personality and social disorders to abnormal white matter (WM) integrity in the right hemisphere. Here, we tested the hypothesis that interpersonal competencies are associated with integrity of WM tracts in the right hemisphere of healthy young adults. Thirty-one participants underwent diffusion tensor imaging scanning. Fractional anisotropy was used to quantify water diffusion. After the scanning session, participants completed the Adolescent Interpersonal Competence Questionnaire. Fractional anisotropy was subsequently correlated with Adolescent Interpersonal Competence Questionnaire scores using tract-based spatial statistics. Higher interpersonal competencies are related to higher WM integrity in several major tracts of the right hemisphere, in specific the uncinate fasciculus, the cingulum, the forceps minor, the infero-fronto occipital fasciculus, the inferior longitudinal fasciculus, and the superior longitudinal fasciculus. These results provide the first direct analysis of the neuroanatomical basis of interpersonal competencies and young adult self-reported skills in social contexts.

Infant cries are a critical survival mechanism that draw the attention of adult caregivers, who can then satisfy the basic needs of otherwise helpless infants. Here, we used functional neuroimaging to determine the effects of infant hunger cries on the brain activity of adults who were in a cognitively nondemanding mental state of awake rest. We found that the brains of men and women, independent of parental status (parent or nonparent), reacted differently to infant cries. Specifically, the dorsal medial prefrontal and posterior cingulate areas, known to be involved in mind wandering (the stream of thought typical of awake rest), remained active in men during exposure to infant cries, whereas in women, activity in these regions decreased. These results show sex-dependent modulation of brain responses to infant requests to be fed, and specifically, they indicate that women interrupt mind wandering when exposed to the sounds of infant hunger cries, whereas men carry on without interruption.

This study used fMRI to measure brain activity during adult processing of cries of infants with autistic disorder (AD) compared to cries of typically developing (TD) infants. Using whole brain analysis, we found that cries of infants with AD compared to those of TD infants elicited enhanced activity in brain regions associated with verbal and prosodic processing, perhaps because altered acoustic patterns of AD cries render them especially difficult to interpret, and increased activity in brain regions associated with emotional processing, indicating that AD cries also elicit more negative feelings and may be perceived as more aversive and/or arousing. Perceived distress engendered by AD cries related to increased activation in brain regions associated with emotional processing. This study supports the hypothesis that cry is an early and meaningful anomaly displayed by children with AD. It could be that cries associated with AD alter parent-child interactions much earlier than the time that reliable AD diagnosis normally occurs., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

During task executions, brain activity increases in executive networks (ENs) and decreases in default-mode networks (DMNs). Here, we examined whether these large-scale network dynamics can be influenced by unconscious cognitive information processing. Volunteers saw instructions (cues) to respond either ipsilaterally or contralaterally to a subsequent lateralized target. Unbeknownst to them, each cue was preceded by a masked stimulus (prime), which could be identical (congruent), or opposite (incongruent) to the cue, or neutral (not an instruction). Behaviorally, incongruent primes interfered with performance, even though they were not consciously perceived. With functional magnetic resonance imaging, we individuated the anticorrelated ENs and DMNs involved during task execution. With effective connectivity analyses, we found that DMNs caused activity in ENs throughout the task. Unconscious interference during incongruent trials was associated with a specific activity increase in ENs and an activity drop in DMNs. Intersubject efficiency in performance during incongruent trials was correlated with functional connectivity between specific ENs and DMNs. These results indicate that unconscious instructions can prime activity in ENs and DMNs and suggest that the DMNs play a key role in unconscious monitoring of the environment in the service of efficient resource allocation for task execution.

Integration is a fundamental working memory operation, requiring the insertion of information from one task into the execution of another concurrent task. Previous neuroimaging studies have suggested the involvement of left anterior prefrontal cortex (L-aPFC) in relation to working memory integration demands, increasing during presentation of information to be integrated (loading), throughout its maintenance during a secondary task, up to the integration step, and then decreasing afterward (unloading). Here we used short bursts of 5 Hz repetitive Transcranic Magnetic Stimulation (rTMS) to modulate L-aPFC activity and to assess its causal role in integration. During experimental blocks, rTMS was applied (N = 10) over L-aPFC or vertex (control site) at different time-points of a task involving integration of a preloaded digit into a sequence of arithmetical steps, and contrasted with a closely matched task without integration demand (segregation). When rTMS was applied during the loading phase, reaction times during secondary task were faster, without significant changes in error rates. RTMS instead worsened performance when applied during information unloading. In contrast, no effects were observed when rTMS was applied during the other phases of integration, or during the segregation condition. These results confirm the hypothesis that L-aPFC is causally and selectively involved in the integration of information in working memory. They additionally suggest that pre-integration loading and post-integration unloading of information involving this area may be active and resource-consuming processes.

Despite the recent interest in the neuroanatomy of inductive reasoning processes, the regional specificity within prefrontal cortex (PFC) for the different mechanisms involved in induction tasks remains to be determined. In this study, we used fMRI to investigate the contribution of PFC regions to rule acquisition (rule search and rule discovery) and rule following. Twenty-six healthy young adult participants were presented with a series of images of cards, each consisting of a set of circles numbered in sequence with one colored blue. Participants had to predict the position of the blue circle on the next card. The rules that had to be acquired pertained to the relationship among succeeding stimuli. Responses given by subjects were categorized in a series of phases either tapping rule acquisition (responses given up to and including rule discovery) or rule following (correct responses after rule acquisition). Mid-dorsolateral PFC (mid-DLPFC) was active during rule search and remained active until successful rule acquisition. By contrast, rule following was associated with activation in temporal, motor, and medial/anterior prefrontal cortex. Moreover, frontopolar cortex (FPC) was active throughout the rule acquisition and rule following phases before a rule became familiar. We attributed activation in mid-DLPFC to hypothesis generation and in FPC to integration of multiple separate inferences. The present study provides evidence that brain activation during inductive reasoning involves a complex network of frontal processes and that different subregions respond during rule acquisition and rule following phases.

Humans make several eye movements every second, and thus a fundamental challenge in conscious vision is to maintain continuity by matching object representations in constantly shifting retinal coordinates. One possible mechanism for visual stability is the remapping of receptive fields around saccade onset, combining pre- and postsaccadic information. The mislocalization of stimuli briefly flashed near the time of saccades has been taken as evidence for remapping. Yet the relationship between remapping, mislocalization, and trans-saccadic integration remains unclear. We asked participants to identify a target stimulus presented around the time of saccade onset, which was immediately visually masked by a postsaccadic stimulus presented in the same spatial location (backward masking). Presenting two rapidly occurring events across separate fixations allowed us to investigate how the visual system reconstructs what happens during a saccade. We show that saccadic remapping resulted in perception of target and mask as either spatially segregated or integrated, depending on the exact timing of saccade onset. During segregation, the target was unmasked because it was perceived as displaced from the mask; during integration, the postsaccadic stimulus masked the presaccadic target (spatiotopic masking). Thus, segregation and integration may work together to yield continuity in conscious vision.

The execution of complex working memory tasks often requires various cognitive control operations on stored content. Here we focus on the integration operation - defined as merging the outcome of subtask processing with additional information actively maintained before and during subtask execution. In prior work, we identified the anterior prefrontal cortex as critical for integration during mental arithmetic. Here we replicate and extend these results in an adapted mental arithmetic task that enabled examination of the detailed temporal dynamics of the anterior prefrontal activation. We find that this region is involved in the preparation for integration, possibly by ensuring that goal-relevant information is maintained in an accessible form, while at the same time protected from subtask interference.

Control processes are thought to play an important role in working memory (WM), by enabling the coordination, transformation, and integration of stored information. Yet little is known about the neural mechanisms that subserve such control processes. This study examined whether integration operations within WM involve the activation of distinct neural mechanisms within lateral prefrontal cortex (PFC). Event-related functional magnetic resonance imaging was used to monitor brain activity while participants performed a mental arithmetic task. In the integration (IN) condition, a WM preload item had to be mentally inserted into the last step of the math problem. This contrasted with the segregation (SG) condition, which also required maintenance of the WM preload while performing mental arithmetic but had no integration requirement. Two additional control conditions involved either ignoring the preload (math only condition) or ignoring the math problem (recall only condition). Left anterior PFC (Brodmann's Area [BA] 46/10) was selectively engaged by integration demands, with activation increasing prior to, as well as during the integration period. A homologous right anterior PFC region showed selectively increased activity in the SG condition during the period in which the math problem and preload digit were reported. Left middorsolateral PFC regions (BA 9/46) showed increased, but equivalent, activity in both the SG and IN conditions relative to both control conditions. These results provide support for the selective role of lateral PFC in cognitive control over WM and suggest more specific hypotheses regarding dissociable PFC mechanisms involved during the integration and segregation of stored WM items.