Structural and functional whole brain changes in autism spectrum disorder at different age stages

Autism spectrum disorder (ASD) is a developmental disorder involving regional changes and local neural disturbances. However, few studies have investigated the dysfunctional phenomenon across different age stages. This study explores the structural and functional brain changes across different developmental stages in individuals with ASD, focusing on childhood (6-12 years), adolescence (12-18 years), and adulthood (18 + years). Using a comprehensive set of neuroimaging metrics, including modulated and non-modulated voxel-based morphometry (VBM), regional homogeneity (ReHo), amplitude of low-frequency fluctuation (ALFF), and fractional ALFF (fALFF), we identified significant stage-specific alterations in both VBM and functional measurements. Our results reveal that ASD is associated with progressive and stage-specific abnormalities in brain structure and function, with distinct patterns emerging at each developmental stage. Specifically, we observed significant modulated VBM reductions in the precuneus, lentiform nucleus, and inferior parietal lobule, accompanied by increases in the midbrain and sub-gyral regions. Moreover, we observed unmodulated VBM increment in regions including lentiform nucleus and thalamus. Functionally, ReHo analyses demonstrated disrupted local synchronization in the medial frontal gyrus, while ALFF and fALFF metrics highlighted altered spontaneous brain activity in the sub-gyral and sub-lobar. Finally, correlation analyses revealed that stage-specific findings are closely linked to clinical social- and behavior-related scores, with VBM in the inferior parietal lobule and putamen as well as ReHo in supplemental motor area being significantly associated with restrictive repetitive behaviors in childhood. These findings underscore the importance of considering age-specific brain changes when studying ASD and suggest that targeted interventions may be necessary at different developmental stages.

Sex modulated the relationship between trait approach motivation and decision-making

It has been observed that one's Behavioral Approach System (BAS) can have an effect on decision-making under uncertainty, although the results have been mixed. To discern the underlying neural substrates, we hypothesize that sex may explain the conflicting results. To test this idea, a large sample of participants was studied using resting state fMRI, utilizing fractional Amplitude of Low Frequency Fluctuations (fALFF) and Resting-State Functional Connectivity (rsFC) techniques. The results of the Iowa Gambling Task (IGT) revealed an interaction between sex and BAS, particularly in the last 60 trials (decision-making under risk). Males with high BAS showed poorer performance than those with low BAS. fALFF analysis showed a significant interaction between BAS group and sex in the left superior occipital gyrus, as well as the functional connectivity between this region and the left ventrolateral prefrontal cortex. Additionally, this functional connectivity was further positively correlated with male performance in the IGT, particularly in the decision-making under risk stage. Furthermore, it was found that the functional connectivity between left ventrolateral prefrontal cortex and left superior occipital gyrus could mediate the relationship between BAS and decision-making in males, particularly in the decision-making under risk stage. These results suggest possible sex-based differences in decision-making, providing an explanation for the inconsistent results found in prior research. Since the research was carried out exclusively with Chinese university students, it is essential to conduct further studies to investigate whether the findings can be generalized.

The brain markers of creativity measured by divergent thinking in childhood: Hippocampal volume and functional connectivity

Creativity, a high-order cognitive ability, has received wide attention from researchers and educators who are dedicated to promoting its development throughout one's lifespan. Currently, creativity is commonly assessed with divergent thinking tasks, such as the Alternative Uses Task. Recent advancements in neuroimaging techniques have enabled the identification of brain markers for high-order cognitive abilities. One such brain structure of interest in this regard is the hippocampus, which has been found to play an important role in generating creative thoughts in adulthood. However, such role of the hippocampus in childhood is not clear. Thus, this study aimed to investigate the associations between creativity, as measured by divergent thinking, and both the volume of the hippocampus and its resting-state functional connectivity in 116 children aged 8-12 years. The results indicate significant relations between divergent thinking and the volume of the hippocampal head and the hippocampal tail, as well as the volume of a subfield comprising cornu ammonis 2-4 and dentate gyrus within the hippocampal body. Additionally, divergent thinking was significantly related to the differences between the anterior and the posterior hippocampus in their functional connectivity to other brain regions during rest. These results suggest that these two subregions may collaborate with different brain regions to support diverse cognitive processes involved in the generation of creative thoughts. In summary, these findings indicate that divergent thinking is significantly related to the structural and functional characteristics of the hippocampus, offering potential insights into the brain markers for creativity during the developmental stage.

Low-frequency rTMS induces modifications in cortical structural connectivity - functional connectivity coupling in schizophrenia patients with auditory verbal hallucinations

Auditory verbal hallucinations (AVH) are distinctive clinical manifestations of schizophrenia. While low-frequency repetitive transcranial magnetic stimulation (rTMS) has demonstrated potential in mitigating AVH, the precise mechanisms by which it operates remain obscure. This study aimed to investigate alternations in structural connectivity and functional connectivity (SC-FC) coupling among schizophrenia patients with AVH prior to and following treatment with 1 Hz rTMS that specifically targets the left temporoparietal junction. Initially, patients exhibited significantly reduced macroscopic whole brain level SC-FC coupling compared to healthy controls. Notably, SC-FC coupling increased significantly across multiple networks, including the somatomotor, dorsal attention, ventral attention, frontoparietal control, and default mode networks, following rTMS treatment. Significant alternations in SC-FC coupling were noted in critical nodes comprising the somatomotor network and the default mode network, such as the precentral gyrus and the ventromedial prefrontal cortex, respectively. The alternations in SC-FC coupling exhibited a correlation with the amelioration of clinical symptom. The results of our study illuminate the intricate relationship between white matter structures and neuronal activity in patients who are receiving low-frequency rTMS. This advances our understanding of the foundational mechanisms underlying rTMS treatment for AVH.

Baseline Frontoparietal Gray Matter Volume Predicts Executive Function Performance in Aging and Mild Cognitive Impairment at 24-Month Follow-Up

Background

Executive dysfunction in mild cognitive impairment (MCI) has been associated with gray matter atrophy. Prior studies have yielded limited insight into associations between gray matter volume and executive function in early and late amnestic MCI (aMCI).

Objective

To examine the relative importance of predictors of executive function at 24 months and relationships between baseline regional gray matter volume and executive function performance at 24-month follow-up in non-demented older adults.

Methods

147 participants from the Alzheimer's Disease Neuroimaging Initiative (mean age = 70.6 years) completed brain magnetic resonance imaging and neuropsychological testing and were classified as cognitively normal (n = 49), early aMCI (n = 60), or late aMCI (n = 38). Analyses explored the importance of demographic, APOEɛ4, biomarker (p-tau/Aβ42, t-tau/Aβ42), and gray matter regions-of-interest (ROI) variables to 24-month executive function, whether ROIs predicted executive function, and whether relationships varied by baseline diagnostic status.

Results

Across all participants, baseline anterior cingulate cortex and superior parietal lobule volumes were the strongest predictors of 24-month executive function performance. In early aMCI, anterior cingulate cortex volume was the strongest predictor and demonstrated a significant interaction such that lower volume related to worse 24-month executive function in early aMCI. Educational attainment and inferior frontal gyrus volume were the strongest predictors of 24-month executive function performance for cognitively normal and late aMCI groups, respectively.

Conclusions

Baseline frontoparietal gray matter regions were significant predictors of executive function performance in the context of aMCI and may identify those at risk of Alzheimer's disease. Anterior cingulate cortex volume may predict executive function performance in early aMCI.

The parietal cortex has a causal role in ambiguity computations in humans

Humans often face the challenge of making decisions between ambiguous options. The level of ambiguity in decision-making has been linked to activity in the parietal cortex, but its exact computational role remains elusive. To test the hypothesis that the parietal cortex plays a causal role in computing ambiguous probabilities, we conducted consecutive fMRI and TMS-EEG studies. We found that participants assigned unknown probabilities to objective probabilities, elevating the uncertainty of their decisions. Parietal cortex activity correlated with the objective degree of ambiguity and with a process that underestimates the uncertainty during decision-making. Conversely, the midcingulate cortex (MCC) encodes prediction errors and increases its connectivity with the parietal cortex during outcome processing. Disruption of the parietal activity increased the uncertainty evaluation of the options, decreasing cingulate cortex oscillations during outcome evaluation and lateral frontal oscillations related to value ambiguous probability. These results provide evidence for a causal role of the parietal cortex in computing uncertainty during ambiguous decisions made by humans.

Brain structural alterations in internet gaming disorder: Focus on the mesocorticolimbic dopaminergic system

AIMS

This study aimed to identify gray/white matter volume (GMV/WMV) alterations in Internet Gaming Disorder (IGD), with a special focus on the subregions of the mesocorticolimbic dopaminergic system and their clinical association.

RESULTS

Compared with healthy controls, IGDs showed bigger GMV in the bilateral caudate and the left nucleus accumbens (NAc), and bigger WMV in the inferior parietal lobule. The comparison of regions of interest (ROI) confirmed increased GMV in the bilateral caudate (including the dorsal anterior, body, and tail) and the left core of NAc in IGD, but no significant WMV alterations in the mesocorticolimbic dopaminergic system. GMVs in the left lateral orbital gyrus of orbitofrontal cortex (OFC) were associated with craving for games, while GMVs in the left anterior insula, right NAc, right caudate, and right OFC were associated with self-control in IGD.

CONCLUSIONS

IGD was accompanied by changed GMV, but not WMV, in the mesocorticolimbic dopaminergic system. GMV in the mesocorticolimbic dopaminergic system may contribute to impaired self-control and craving in IGD.

Distributed attribute representation in the superior parietal lobe during probabilistic decision-making

Several studies have examined the neural substrates of probabilistic decision-making, but few have systematically investigated the neural representations of the two objective attributes of probabilistic rewards, that is, the reward amount and the probability. Specifically, whether there are common or distinct neural activity patterns to represent the objective attributes and their association with the neural representation of the subjective valuation remains largely underexplored. We conducted two studies (nStudy1  = 34, nStudy2  = 41) to uncover distributed neural representations of the objective attributes and subjective value as well as their association with individual probability discounting rates. The amount and probability were independently manipulated to better capture brain signals sensitive to these two attributes and were presented simultaneously in Study 1 and successively in Study 2. Both univariate and multivariate pattern analyses showed that the brain activities in the superior parietal lobule (SPL), including the postcentral gyrus, were modulated by the amount of rewards and probability in both studies. Further, representational similarity analysis revealed a similar neural representation between these two objective attributes and between the attribute and valuation. Moreover, the SPL tracked the subjective value integrated by the hyperbolic function. Probability-related brain activations in the inferior parietal lobule were associated with the variability in individual discounting rates. These findings provide novel insights into a similar neural representation of the two attributes during probabilistic decision-making and perhaps support the common neural coding of stimulus objective properties and subjective value in the field of probabilistic discounting.

Genetic variation in the dopamine system is associated with mixed-strategy decision-making in patients with Parkinson's disease

Decision-making during mixed-strategy games requires flexibly adapting choice strategies in response to others' actions and dynamically tracking outcomes. Such decisions involve diverse cognitive processes, including reinforcement learning, which are affected by disruptions to the striatal dopamine system. We therefore investigated how genetic variation in dopamine function affected mixed-strategy decision-making in Parkinson's disease (PD), which involves striatal dopamine pathology. Sixty-six PD patients (ages 49-85, Hoehn and Yahr Stages 1-3) and 22 healthy controls (ages 54-75) competed in a mixed-strategy game where successful performance depended on minimizing choice biases (i.e., flexibly adapting choices trial by trial). Participants also completed a fixed-strategy task that was matched for sensory input, motor outputs and overall reward rate. Factor analyses were used to disentangle cognitive from motor aspects within both tasks. Using a within-subject, multi-centre design, patients were examined on and off dopaminergic therapy, and genetic variation was examined via a multilocus genetic profile score representing the additive effects of three single nucleotide polymorphisms (SNPs) that influence dopamine transmission: rs4680 (COMT Val158 Met), rs6277 (C957T) and rs907094 (encoding DARPP-32). PD and control participants displayed comparable mixed-strategy choice behaviour (overall); however, PD patients with genetic profile scores indicating higher dopamine transmission showed improved performance relative to those with low scores. Exploratory follow-up tests across individual SNPs revealed better performance in individuals with the C957T polymorphism, reflecting higher striatal D2/D3 receptor density. Importantly, genetic variation modulated cognitive aspects of performance, above and beyond motor function, suggesting that genetic variation in dopamine signalling may underlie individual differences in cognitive function in PD.

Differential processing of risk and reward in delinquent and non-delinquent youth

The present study examined the behavioral and neural differences in risky decision-making between delinquent (n = 23) and non-delinquent (n = 27) youth ages 13-17 years (M = 16, SD = 0.97) in relation to reward processing. While undergoing functional neuroimaging, participants completed an experimental risk task wherein they received feedback about the riskiness of their behavior in the form of facial expressions that morphed from happy to angry. Behavioral results indicated that delinquent youth took fewer risks and earned fewer rewards on the task than non-delinquent youth. Results from whole-brain analyses indicated no group differences in sensitivity to punishments (i.e. angry faces), but instead showed that delinquent youth evinced greater neural tracking of reward outcomes (i.e. cash-ins) in regions including the ventral striatum and inferior frontal gyrus. While behavioral results show that delinquent youth were more risk-averse, the neural results indicated that delinquent youth were also more reward-driven, potentially suggesting a preference for immediate rewards. Results offer important insights into differential decision-making processes between delinquent and non-delinquent youth.

Neural fingerprints of gambling disorder using diffusion tensor imaging

Gambling disorder (GD) is a behavioral addiction associated with personal, social and occupational consequences. Thus, examining GD's clinical relationship with its neural substrates is critical. We compared neural fingerprints using diffusion tensor imaging (DTI) in GD subjects undergoing treatment relative to healthy volunteers (HV). Fifty-three (25 GD, 28 age-matched HV) males were scanned with structural magnetic resonance imaging (MRI) and DTI. We applied probabilistic tractography based on DTI scanning data, preprocessed and analyzed using permutation testing of individual connectivity weights between regions for group comparison. Permutation-based comparisons between group-averaged connectomes highlighted significant structural differences. The GD group demonstrated increased connectivity, and striatal network reorganisation, contrasted by reduced connectivity within and to frontal lobe nodes. Modularity analysis revealed that the GD group had fewer hubs integrating information across the brain. We highlight GD neural changes involved in controlling risk-seeking behaviors. The observed striatal restructuring converges with previous research, and the increased connectivity affects subnetworks highly active in gambling situations, although these findings are not significant when correcting for multiple comparisons. Modularity analysis underlines that, despite connectivity increases, the GD connectome loses hubs, impeding its neuronal network coherence. Together, these results demonstrate the feasibility of using whole-brain computational modeling in assessing GD.

Good-enough attentional guidance

Theories of attention posit that attentional guidance operates on information held in a target template within memory. The template is often thought to contain veridical target features, akin to a photograph, and to guide attention to objects that match the exact target features. However, recent evidence suggests that attentional guidance is highly flexible and often guided by non-veridical features, a subset of features, or only associated features. We integrate these findings and propose that attentional guidance maximizes search efficiency based on a 'good-enough' principle to rapidly localize candidate target objects. Candidates are then serially interrogated to make target-match decisions using more precise information. We suggest that good-enough guidance optimizes the speed-accuracy-effort trade-offs inherent in each stage of visual search.

Sex-related differences in violence exposure, neural reactivity to threat, and mental health

The prefrontal cortex (PFC), hippocampus, and amygdala play an important role in emotional health. However, adverse life events (e.g., violence exposure) affect the function of these brain regions, which may lead to disorders such as depression and anxiety. Depression and anxiety disproportionately affect women compared to men, and this disparity may reflect sex differences in the neural processes that underlie emotion expression and regulation. The present study investigated sex differences in the relationship between violence exposure and the neural processes that underlie emotion regulation. In the present study, 200 participants completed a Pavlovian fear conditioning procedure in which cued and non-cued threats (i.e., unconditioned stimuli) were presented during functional magnetic resonance imaging. Violence exposure was previously assessed at four separate time points when participants were 11-19 years of age. Significant threat type (cued versus non-cued) × sex and sex × violence exposure interactions were observed. Specifically, women and men differed in amygdala and parahippocampal gyrus reactivity to cued versus non-cued threat. Further, dorsolateral PFC (dlPFC) and inferior parietal lobule (IPL) reactivity to threat varied positively with violence exposure among women, but not men. Similarly, threat-elicited skin conductance responses varied positively with violence exposure among women. Finally, women reported greater depression and anxiety symptoms than men. These findings suggest that sex differences in threat-related brain and psychophysiological activity may have implications for mental health.

Representation of motion concepts in occipitotemporal cortex: fMRI activation, decoding and connectivity analyses

Embodied theories of semantic cognition predict that brain regions involved in motion perception are engaged when people comprehend motion concepts expressed in language. Left lateral occipitotemporal cortex (LOTC) is implicated in both motion perception and motion concept processing but prior studies have produced mixed findings on which parts of this region are engaged by motion language. We scanned participants performing semantic judgements about sentences describing motion events and static events. We performed univariate analyses, multivariate pattern analyses (MVPA) and psychophysiological interaction (PPI) analyses to investigate the effect of motion on activity and connectivity in different parts of LOTC. In multivariate analyses that decoded whether a sentence described motion or not, the middle and posterior parts of LOTC showed above-chance level performance, with performance exceeding that of other brain regions. Univariate ROI analyses found the middle part of LOTC was more active for motion events than static ones. Finally, PPI analyses found that when processing motion events, the middle and posterior parts of LOTC (overlapping with motion perception regions), increased their connectivity with cognitive control regions. Taken together, these results indicate that the more posterior parts of LOTC, including motion perception cortex, respond differently to motion vs. static events. These findings are consistent with embodiment accounts of semantic processing, and suggest that understanding verbal descriptions of motion engages areas of the occipitotemporal cortex involved in perceiving motion.

Shared and specific patterns of dynamic functional connectivity variability of striato-cortical circuitry in unmedicated bipolar and major depressive disorders

BACKGROUND

Accumulating studies have found structural and functional abnormalities of the striatum in bipolar disorder (BD) and major depressive disorder (MDD). However, changes in intrinsic brain functional connectivity dynamics of striato-cortical circuitry have not been investigated in BD and MDD. This study aimed to investigate the shared and specific patterns of dynamic functional connectivity (dFC) variability of striato-cortical circuitry in BD and MDD.

METHODS

Brain resting-state functional magnetic resonance imaging data were acquired from 128 patients with unmedicated BD II (current episode depressed), 140 patients with unmedicated MDD, and 132 healthy controls (HCs). Six pairs of striatum seed regions were selected: the ventral striatum inferior (VSi) and the ventral striatum superior (VSs), the dorsal-caudal putamen (DCP), the dorsal-rostral putamen (DRP), and the dorsal caudate and the ventral-rostral putamen (VRP). The sliding-window analysis was used to evaluate dFC for each seed.

RESULTS

Both BD II and MDD exhibited increased dFC variability between the left DRP and the left supplementary motor area, and between the right VRP and the right inferior parietal lobule. The BD II had specific increased dFC variability between the right DCP and the left precentral gyrus compared with MDD and HCs. The MDD had increased dFC variability between the left VSi and the left medial prefrontal cortex compared with BD II and HCs.

CONCLUSIONS

The patients with BD and MDD shared common dFC alteration in the dorsal striatal-sensorimotor and ventral striatal-cognitive circuitries. The patients with MDD had specific dFC alteration in the ventral striatal-affective circuitry.

Repetitive transcranial magnetic stimulation modulates coupling among large-scale brain networks in heroin-dependent individuals: A randomized resting-state functional magnetic resonance imaging study

The abnormal interactions of three key large-scale brain networks (default mode [DMN], salience and executive control [ECN]) were showed underlie dysfunctions in heroin addiction. Repetitive transcranial magnetic stimulation (rTMS) targeting the left dorsolateral prefrontal cortex (DLPFC) is a potential treatment for heroin addiction. It is unclear whether impaired coupling among the large-scale brain networks would be improved by rTMS in treated heroin-dependent individuals. Thirty-five heroin-dependent individuals were included in this sham-controlled, randomized study. The patients received either active or sham rTMS for 1 week. The craving for heroin and resting-state functional magnetic resonance imaging data were collected before and after 1-week rTMS. Twenty-two healthy subjects were included as controls not receiving rTMS. After 1-week rTMS, only the active rTMS group showed a significant decrease in spontaneous and heroin cue-induced craving. The coupling between left DLPFC (a key node of left ECN) and left parahippocampal gyrus (PHG, included in DMN) significantly increased for the active group with a tendency towards that of controls. The coupling between the right precentral gyrus and three key regions included in DMN (posterior cingulate cortex/precuneus and bilateral inferior parietal cortex) significantly decreased for the active group with a tendency towards that of healthy controls. For the active rTMS individuals, the left DLPFC-PHG coupling negatively correlated with the spontaneous craving and the drug cue-induced craving. It suggested that the rTMS could reduce heroin craving, which might be related to the modulation of ECN-DMN coupling. This finding might shed light on the mechanism of rTMS for heroin addiction treatment.

Impulsivity and Emotional Dysregulation Predict Choice Behavior During a Mixed-Strategy Game in Adolescents With Borderline Personality Disorder

Impulsivity and emotional dysregulation are two core features of borderline personality disorder (BPD), and the neural mechanisms recruited during mixed-strategy interactions overlap with frontolimbic networks that have been implicated in BPD. We investigated strategic choice patterns during the classic two-player game, Matching Pennies, where the most efficient strategy is to choose each option randomly from trial-to-trial to avoid exploitation by one’s opponent. Twenty-seven female adolescents with BPD (mean age: 16 years) and twenty-seven age-matched female controls (mean age: 16 years) participated in an experiment that explored the relationship between strategic choice behavior and impulsivity in both groups and emotional dysregulation in BPD. Relative to controls, BPD participants showed marginally fewer reinforcement learning biases, particularly decreased lose-shift biases, increased variability in reaction times (coefficient of variation; CV), and a greater percentage of anticipatory decisions. A subset of BPD participants with high levels of impulsivity showed higher overall reward rates, and greater modulation of reaction times by outcome, particularly following loss trials, relative to control and BPD participants with lower levels of impulsivity. Additionally, BPD participants with higher levels of emotional dysregulation showed marginally increased reward rate and increased entropy in choice patterns. Together, our preliminary results suggest that impulsivity and emotional dysregulation may contribute to variability in mixed-strategy decision-making in female adolescents with BPD.

Resting state predicts neural activity during reward-guided decision making: An fMRI study on Balloon Analogue Risk Task

In our previous work [8], we have shown that resting state (RS) functional connectivity metrics are significantly related with behavioural performance at Balloon Analogue Risk Task (BART). In the present study we investigated the hypothesis of an association between RS metrics and neural activity evoked by BART execution. A group-level whole-brain regression was run to assess whether RS metrics predict brain activation during the BART, in a sample of 35 young healthy adults (mean age 23 ± 2 years, 25 F). Results complete the previous findings showing that RS is also significantly associated with the neural activity during BART execution. Specifically, ALFF is positively associated with the activity of both the right inferior parietal lobule and the left caudate. These new results are coherent with previous evidence indicating RS abnormalities in clinical conditions characterised by symptoms of impulse control disorders, and further suggest that RS might be a stable predictor of both behavioural indices and neural correlates of impulsivity and of reward-guided decision-making.

Increased ALFF and functional connectivity of the right striatum in bipolar disorder patients

BACKGROUND

Bipolar disorder (BD) is a serious neuropsychiatric disorder characterized by alternating periods of mania, depression, and euthymia. Abnormal spontaneous brain activity within the cortical-striatal neural circuits has been observed in patients with BD. However, whether the abnormality appears in patients with BD while not in a manic mood state is unclear.

METHODS

This study collected resting-state fMRI data from 65 patients with BD who were not in a manic mood state and 85 matched healthy controls. First, we examined differences in amplitude of low-frequency fluctuations (ALFF) between the patients with BD and the healthy controls to identify regions that show abnormal local spontaneous activity in the patients. Based on the ALFF results, we conducted seed-based resting-state functional connectivity (rsFC) analysis to identify the changes in brain networks that are centered on the regions showing abnormal local spontaneous activity in the patients. Finally, we repeated these analyses in a sub-sample comprising euthymic BD patients (N = 37) and between the euthymic BD patients and all the other patients who had at least mild depressive symptoms.

RESULTS

BD patients exhibited increased ALFF in the right caudate/putamen and increased rsFC in the right caudate/putamen with the right inferior parietal lobe (cluster-level FWE p < 0.05). Further analyses showed that the euthymic BD patients showed similar abnormalities in ALFF and rsFC maps as found in all patients with BD. And the euthymic BD patients were comparable with all the other patients who had at least mild depressive symptoms in ALFF values.

CONCLUSIONS

Our results indicated the important role of the right striatum in the baseline brain function of BD patients and suggested that the abnormality of spontaneous brain activity in the cortical-striatal neural circuits may be a trait-like variant in patients with BD. The results deepen our understanding of the neurobiological mechanisms associated with BD etiology.

Watershed Brain Regions for Characterizing Brand Equity-Related Mental Processes

Brand equity is an important intangible for enterprises. As one advantage, products with brand equity can increase revenue, compared with those without such equity. However, unlike tangibles, it is difficult for enterprises to manage brand equity because it exists within consumers’ minds. Although, over the past two decades, numerous consumer neuroscience studies have revealed the brain regions related to brand equity, the identification of unique brain regions related to such equity is still controversial. Therefore, this study identifies the unique brain regions related to brand equity and assesses the mental processes derived from these regions. For this purpose, three analysis methods (i.e., the quantitative meta-analysis, chi-square tests, and machine learning) were conducted. The data were collected in accordance with the general procedures of a qualitative meta-analysis. In total, 65 studies (1412 foci) investigating branded objects with brand equity and unbranded objects without brand equity were examined, whereas the neural systems involved for these two brain regions were contrasted. According to the results, the parahippocampal gyrus and the lingual gyrus were unique brand equity-related brain regions, whereas automatic mental processes based on emotional associative memories derived from these regions were characteristic mental processes that discriminate branded from unbranded objects.

Neural Correlates of Garment Fit and Purchase Intention in the Consumer Decision-Making Process and the Influence of Product Presentation

In today’s competitive e-commerce markets, it is crucial to promote product satisfaction and to quickly identify purchase intention in decision-making consumers. The present investigation examined the relationship between perceived garment fit and purchase intention, together with how product presentation methods (mannequin versus self-model) contribute to decision-making processes of clothing. Thirty-nine female volunteers were scanned using fMRI while performing an online shopping task. In Part 1, univariate analysis was conducted between garment fit and product presentation factors to assess their effects on purchase deliberation. In Part 2, univariate, multivariate pattern, and psychophysiological interaction analyses were carried out to examine the predictive ability of fit evaluation and product presentation on purchase intention. First, garment fit × product presentation interaction effects on purchase deliberation were observed in the frontopolar cortex, superior frontal gyrus, anterior cingulate cortex, and posterior cingulate cortex. Part 2 demonstrated neural signals of the dorsomedial prefrontal cortex, premotor cortex, supplementary motor area, superior parietal lobule, supramarginal gyrus, superior temporal sulcus, fusiform gyrus, and insula to distinguish subsequent purchase intentions. Overall, the findings denote directed exploration, visual and action processing as key neural processes in decision-making that uniquely reflect garment fit and product presentation type during purchase deliberation. Additionally, with respect to the effects of purchase intention on product evaluation, the evidence conveys that mental interactions with products and social cognition are fundamental processes that capture subsequent purchase intention at the product evaluation stage.

Predictive processing, cognitive control, and tonality stability of music: An fMRI study of chromatic harmony

The present study aimed at identifying the brain regions which preferentially responded to music with medium degrees of key stability. There were three types of auditory stimuli. Diatonic music based strictly on major and minor scales has the highest key stability, whereas atonal music has the lowest key stability. Between these two extremes, chromatic music is characterized by sophisticated uses of out-of-key notes, which challenge the internal model of musical pitch and lead to higher precision-weighted prediction error compared to diatonic and atonal music. The brain activity of 29 adults with excellent relative pitch was measured with functional magnetic resonance imaging while they listened to diatonic music, chromatic music, and atonal random note sequences. Several frontoparietal regions showed significantly greater response to chromatic music than to diatonic music and atonal sequences, including the pre-supplementary motor area (extending into the dorsal anterior cingulate cortex), dorsolateral prefrontal cortex, rostrolateral prefrontal cortex, intraparietal sulcus, and precuneus. We suggest that these frontoparietal regions may support working memory processes, hierarchical sequencing, and conflict resolution of remotely related harmonic elements during the predictive processing of chromatic music. This finding suggested a possible correlation between precision-weighted prediction error and the frontoparietal regions implicated in cognitive control.

Are Rank Orders Mentally Represented by Spatial Arrays?

The present contribution argues that transitive reasoning, as exemplified in paradigms of linear order construction in mental space, is associated with spatial effects. Starting from robust findings from the early 70s, research so far has widely discussed the symbolic distance effect (SDE). This effect shows that after studying pairs of relations, e.g., "A > B," "B > C," and "D > E," participants are more correct, and faster in correct responding, the wider the "distance" between two elements within the chain A > B > C > D > E. The SDE has often been given spatial interpretations, but alternatively, non-spatial models of the effect are also viable on the empirical basis so far, which means the question about spatial contributions to the construction of analog representations of rank orders is still open. We suggest here that laterality effects can add the necessary additional information to support the idea of spatial processes. We introduce anchoring effects in terms of showing response advantages for congruent versus incongruent pairings of presentation location on a screen on the one hand, and the hypothetical spatial arrangement of the order in mental space, on the other hand. We report pertinent findings and discuss anchoring paradigms with respect to their internal validity as well as their being rooted in basic mechanisms of trained reading/writing direction.

fMRI evidence reveals emotional biases in bilingual decision making

Research indicates that the foreign language effect on decision making can be partially explained by a reduction in emotional response in the second language. In this fMRI study, we aimed at elucidating the neural mechanisms underpinning the interaction between language and emotion in decision making. Across multiple trials, Chinese-English bilinguals were asked to decide whether to gamble in a Gambling task, and received feedbacks either in L1 (Chinese) or in L2 (English). If they gambled, feedbacks were either positively or negatively valenced words; if they did not gamble, feedback was the word 'safe'. We assessed how emotionally valenced words were processed in the two languages, and how this processing influenced subsequent decision making. Overall, we found evidence that in L2 context, but not in L1 context, loss aversion was mediated by the dorsolateral prefrontal cortex (dlPFC) which also showed strong functional connectivity with the visual cortex, suggesting an avoidance mechanism for negative stimuli in L2. However, we also found an enhanced response to positive feedbacks in L2 compared to L1, as evidenced by greater activation of the hippocampus for win feedbacks compared to safe feedbacks in L2, eventually resulting in a greater tendency to gamble. Thus, foreign language influenced decision making by both regulating emotional response to negative stimuli and enhancing emotional response to positive stimuli. This study helps unveiling the neural bases of the interaction between language and emotion in the foreign language context.

Lexical Influences on Categorical Speech Perception Are Driven by a Temporoparietal Circuit

Categorical judgments of otherwise identical phonemes are biased toward hearing words (i.e., "Ganong effect") suggesting lexical context influences perception of even basic speech primitives. Lexical biasing could manifest via late stage postperceptual mechanisms related to decision or, alternatively, top-down linguistic inference that acts on early perceptual coding. Here, we exploited the temporal sensitivity of EEG to resolve the spatiotemporal dynamics of these context-related influences on speech categorization. Listeners rapidly classified sounds from a /gɪ/-/kɪ/ gradient presented in opposing word-nonword contexts (GIFT-kift vs. giss-KISS), designed to bias perception toward lexical items. Phonetic perception shifted toward the direction of words, establishing a robust Ganong effect behaviorally. ERPs revealed a neural analog of lexical biasing emerging within ~200 msec. Source analyses uncovered a distributed neural network supporting the Ganong including middle temporal gyrus, inferior parietal lobe, and middle frontal cortex. Yet, among Ganong-sensitive regions, only left middle temporal gyrus and inferior parietal lobe predicted behavioral susceptibility to lexical influence. Our findings confirm lexical status rapidly constrains sublexical categorical representations for speech within several hundred milliseconds but likely does so outside the purview of canonical auditory-sensory brain areas.

QEEG coherence patterns related to mathematics ability in children

The current study investigates the utility of resting-state EEG coherence values in predicting standardized math scores in children. Quantitative EEG and standardized academic achievement analyses were performed on 60 school-aged children. Analyses assessing intrahemispheric coherence at rest were conducted across the sample of participants and several coherence networks were extracted and compared to standardized math achievement values. Specifically, networks that included Brodmann area 40 (a brain region involved in the cognitive processes responsible for mathematics performance) and whose coherence values were significantly correlated with standardized math scores were examined. Results indicate a total of four coherence networks, two in each hemisphere, that have utility in predicting general math skills in children. In addition to BA 40, these coherence networks include BAs in the right temporal lobe, right frontoparietal lobe, left superior temporal lobe, and the left medial prefrontal cortex. These findings address the current dearth of research on the neurological connectivity patterns that are foundational for mathematics abilities in children. Further, these results lay a foundation for the supplementary use of EEG in the assessment and identification practices surrounding math learning disabilities in children and additionally provide a neurocognitive framework upon which intervention research may be targeted.

Frontal, Parietal, and Temporal Brain Areas Are Differentially Activated When Disambiguating Potential Objects of Joint Attention

Humans establish joint attention with others by following the other's gaze. Previous work has suggested that a cortical patch (gaze-following patch, GFP) close to the posterior superior temporal sulcus (pSTS) may serve as a link between the extraction of the other's gaze direction and the resulting shifts of attention, mediated by human lateral intraparietal area (hLIP). However, it is not clear how the brain copes with situations in which information on gaze direction alone is insufficient to identify the target object because more than one may lie along the gaze vector. In this fMRI study, we tested human subjects on a paradigm that allowed the identification of a target object based on the integration of the other's gaze direction and information provided by an auditory cue on the relevant object category. Whereas the GFP activity turned out to be fully determined by the use of gaze direction, activity in hLIP reflected the total information needed to pinpoint the target. Moreover, in an exploratory analysis, we found that a region in the inferior frontal junction (IFJ) was sensitive to the total information on the target. An examination of the BOLD time courses in the three identified areas suggests functionally complementary roles. Although the GFP seems to primarily process directional information stemming from the other's gaze, the IFJ may help to analyze the scene when gaze direction and auditory information are not sufficient to pinpoint the target. Finally, hLIP integrates both streams of information to shift attention to distinct spatial locations.

Amygdala 5-HTT Gene Network Moderates the Effects of Postnatal Adversity on Attention Problems: Anatomo-Functional Correlation and Epigenetic Changes

Variations in serotoninergic signaling have been related to behavioral outcomes. Alterations in the genome, such as DNA methylation and histone modifications, are affected by serotonin neurotransmission. The amygdala is an important brain region involved in emotional responses and impulsivity, which receives serotoninergic input. In addition, studies suggest that the serotonin transporter gene network may interact with the environment and influence the risk for psychiatric disorders. We propose to investigate whether/how interactions between the exposure to early life adversity and serotonin transporter gene network in the amygdala associate with behavioral disorders. We constructed a co-expression-based polygenic risk score (ePRS) reflecting variations in the function of the serotonin transporter gene network in the amygdala and investigated its interaction with postnatal adversity on attention problems in two independent cohorts from Canada and Singapore. We also described how interactions between ePRS-5-HTT and postnatal adversity exposure predict brain gray matter density and variation in DNA methylation across the genome. We observed that the expression-based polygenic risk score, reflecting the function of the amygdala 5-HTT gene network, interacts with postnatal adversity, to predict attention and hyperactivity problems across both cohorts. Also, both postnatal adversity score and amygdala ePRS-5-HTT score, as well as their interaction, were observed to be associated with variation in DNA methylation across the genome. Variations in gray matter density in brain regions linked to attentional processes were also correlated to our ePRS score. These results confirm that the amygdala 5-HTT gene network is strongly associated with ADHD-related behaviors, brain cortical density, and epigenetic changes in the context of adversity in young children.

A novel fMRI paradigm to dissociate the behavioral and neural components of mixed-strategy decision making from non-strategic decisions in humans

During competitive interactions, such as predator-prey or team sports, the outcome of one's actions is dependent on both their own choices and those of their opponents. Success in these rivalries requires that individuals choose dynamically and unpredictably, often adopting a mixed strategy. Understanding the neural basis of strategic decision making is complicated by the fact that it recruits various cognitive processes that are often shared with non-strategic forms of decision making, such as value estimation, working memory, response inhibition, response selection, and reward processes. Although researchers have explored neural activity within key brain regions during mixed-strategy games, how brain activity differs in the context of strategic interactions versus non-strategic choices is not well understood. We developed a novel behavioral paradigm to dissociate choice behavior during mixed-strategy interactions from non-strategic choices, and we used task-based functional magnetic resonance imaging (fMRI) to contrast brain activation. In a block design, participants competed in the classic mixed-strategy game, "matching pennies," against a dynamic computer opponent designed to exploit predictability in players' response patterns. Results were contrasted with a non-strategic task that had comparable sensory input, motor output, and reward rate; thus, differences in behavior and brain activation reflect strategic processes. The mixed-strategy game was associated with activation of a distributed cortico-striatal network compared to the non-strategic task. We propose that choosing in mixed-strategy contexts requires additional cognitive demands present to a lesser degree during the control task, illustrating the strength of this design in probing function of cognitive systems beyond core sensory, motor, and reward processes.

Neural mechanisms of risky decision making in adolescents reporting frequent alcohol and/or marijuana use

Because adolescence is a period of heightened exploration of new behaviors, there is a natural increase in risk taking including initial use of alcohol and marijuana. In order to better understand potential differences in neurocognitive functioning among adolescents who use drugs, the current study aimed to identify the neural substrates of risky decision making that differ among adolescents who are primary users of alcohol or marijuana, primary users of both alcohol and marijuana, and controls who report primary use of neither drug. Participants completed the Balloon Analogue Risk Task (BART) while undergoing functional magnetic resonance imaging. Comparison of brain activation during risky decisions versus non-risky decisions across all subjects revealed greater response to risky decisions in dorsal anterior cinguate cortex (dACC), anterior insula, ventral striatum, and lateral prefrontal cortex. Group comparisons across non-using controls, primary marijuana, primary alcohol, and alcohol and marijuana users revealed several notable differences in the recruitment of brain regions. Adolescents who use both alcohol and marijauna show decreased response during risky decision making compared to controls in insula, striatum, and thalamus, and reduced differentiation of increasing risk in dACC, insula, striatum, and superior parietal lobe compared to controls. These results provide evidence of differential engagement of risky decision making circuits among adolescents with varying levels of alcohol and marijuana use, and may provide useful targets for longitudinal studies that explicitly address causality of these differences.

Functional Correlates of Resting-State Connectivity in the Default Mode Network of Heroin Users on Methadone Treatment and Medication-Free Therapeutic Community Program

The treatment of heroin addiction is a complex process involving changes in addictive behavior and brain functioning. The goal of this study was to explore the brain default mode network (DMN) functional connectivity using resting-state functional magnetic resonance imaging (rs-fMRI) and decision-making performance based on the Cambridge gambling task in heroin-dependent individuals undergoing methadone treatment (MT, n = 11) and medication-free faith-based therapeutic community program (TC, n = 11). The DMN involved the medial prefrontal cortex (mPFC), left inferior parietal lobe (IPL_L), right inferior parietal lobe (IPL_R), and posterior cingulate cortex (PCC) subregions for all participants in both the MT and TC groups. Compared with MT, TC had an increased functional connectivity in IPL_L-IPL_R and IPL_R-PCC and decreased functional connectivity in mPFC-IPL_L and IPL_L-PCC. Both groups exhibited no significant difference in the regional rs-fMRI metric [i.e., amplitude of low-frequency fluctuation (ALFF)]. In the analysis of the neural correlates for decision-making performance, risk adjustment was positively associated with ALFF in IPL_L for all participants considering the group effects. The involvement of IPL in decision-making performance and treatment response among heroin-dependent patients warrants further investigation.

Navigating Social Space

Cognitive maps are encoded in the hippocampal formation and related regions and range from the spatial to the purely conceptual. Neural mechanisms that encode information into relational structures, up to an arbitrary level of abstraction, may explain such a broad range of representation. Research now indicates that social life can also be mapped by these mechanisms: others' spatial locations, social memory, and even a two-dimensional social space framed by social power and affiliation. The systematic mapping of social life onto a relational social space facilitates adaptive social decision making, akin to social navigation. This emerging line of research has implications for cognitive mapping research, clinical disorders that feature hippocampal dysfunction, and the field of social cognitive neuroscience.

Investigating the Brain Neural Mechanism when Signature Objects were Masked during a Scene Categorization Task using Functional MRI

Objects play vital roles in scene categorization. Although a number of studies have researched on the neural responses during object and object-based scene recognition, few studies have investigated the neural mechanism underlying object-masked scene categorization. Here, we used functional magnetic resonance imaging (fMRI) to measure the changes in brain activations and functional connectivity (FC) while subjects performed a visual scene-categorization task with different numbers of 'signature objects' masked. The object-selective region in the lateral occipital complex (LOC) showed a decrease in activations and changes in FC with the default mode network (DMN), indicating changes in object attention after the masking of signature objects. Changes in top-down modulation effect were revealed in the FC from the dorsolateral prefrontal cortex (DLPFC) to LOC and the extrastriate visual cortex, possibly participating in conscious object recognition. The whole-brain analyses showed the participation of fronto-parietal network (FPN) in scene categorization judgment, and right DLPFC served as the core hub in this network. Another core hub was found in left middle temporal gyrus (MTG) and its connection with middle cingulate cortex (MCC), supramarginal gyrus (SMG) and insula might serve in the processing of motor response and the semantic relations between objects and scenes. Brain-behavior correlation analysis substantiated the contributions of the FC to the different processes in the object-masked scene-categorization tasks. Altogether, the results suggest that masking of objects significantly affected the object attention, cognitive demand, top-down modulation effect, and semantic judgment.

Activations of the dorsolateral prefrontal cortex and thalamus during agentic self-evaluation are negatively associated with trait self-esteem

Individual self-esteem is dominated more by agency than by communion. However, prior research has mainly focused on one's agentic/communal self-evaluation, while little is known about how one endorses others' agentic/communal evaluation of the self. The present study investigated the associations between trait self-esteem and fundamental dimensions of social cognition, i.e. agency vs. communion, during both self-evaluation and endorsement of others' evaluation of oneself. We also investigated the neural mechanisms underlying the relationship between trait self-esteem and agentic self-evaluation. Behavioral results revealed that self-esteem was positively correlated with the agentic ratings from self-evaluation and endorsement of others' evaluation of the self, and that the agentic self-evaluation was a significant full mediator between self-esteem and endorsement of others' agentic evaluation. Whole-brain regression analysis revealed that self-esteem was negatively correlated with right dorsolateral prefrontal and bilateral thalamic response to agentic self-evaluation. A possible interpretation is that low self-esteem people both hold a more self-critical attitude about the self and have less certainty or clarity of their self-concepts than high self-esteem people do. These findings have important implication for understanding the neural and cognitive mechanisms underlying self-esteem's effect on one's agentic self-evaluations.

Adult Attachment Affects Neural Response to Preference-Inferring in Ambiguous Scenarios: Evidence From an fMRI Study

Humans are highly social animals, and the ability to cater to the preferences of other individuals is encouraged by society. Preference-inferring is an important aspect of the theory of mind (TOM). Many previous studies have shown that attachment style is closely related to TOM ability. However, little is known about the effects of adult attachment style on preferences inferring under different levels of certainty. Here, we investigated how adult attachment style affects neural activity underlying preferences inferred under different levels of certainty by using functional magnetic resonance imaging (fMRI). The fMRI results demonstrated that adult attachment influenced the activation of anterior insula (AI) and inferior parietal lobule (IPL) in response to ambiguous preference-inferring. More specifically, in the ambiguous preference condition, the avoidant attached groups exhibited a significantly enhanced activation than secure and anxious attached groups in left IPL; the anxious attached groups exhibited a significantly reduced activation secure attached group in left IPL. In addition, the anxious attached groups exhibited a significantly reduced activation than secure and avoidant attached groups in left AI. These results were also further confirmed by the subsequent PPI analysis. The results from current study suggest that, under ambiguous situations, the avoidant attached individuals show lower sensitivity to the preference of other individuals and need to invest more cognitive resources for preference-reasoning; while compared with avoidant attached group, the anxious attached individuals express high tolerance for uncertainty and a higher ToM proficiency. Results from the current study imply that differences in preference-inferring under ambiguous conditions associated with different levels of individual attachment may explain the differences in interpersonal interaction.

Behavioral preference in sequential decision-making and its association with anxiety

In daily life, people often make consecutive decisions before the ultimate goal is reached (i.e., sequential decision-making). However, this kind of decision-making has been largely overlooked in the literature. The current study investigated whether behavioral preference would change during sequential decisions, and the neural processes underlying the potential changes. For this purpose, we revised the classic balloon analogue risk task and recorded the electroencephalograph (EEG) signals associated with each step of decision-making. Independent component analysis performed on EEG data revealed that four EEG components elicited by periodic feedback in the current step predicted participants' decisions (gamble vs. no gamble) in the next step. In order of time sequence, these components were: bilateral occipital alpha rhythm, bilateral frontal theta rhythm, middle frontal theta rhythm, and bilateral sensorimotor mu rhythm. According to the information flows between these EEG oscillations, we proposed a brain model that describes the temporal dynamics of sequential decision-making. Finally, we found that the tendency to gamble (as well as the power intensity of bilateral frontal theta rhythms) was sensitive to the individual level of trait anxiety in certain steps, which may help understand the role of emotion in decision-making.

The influences and neural correlates of past and present during gambling in humans

During financial decision-making tasks, humans often make "rational" decisions, where they maximize expected reward. However, this rationality may compete with a bias that reflects past outcomes. That is, if one just lost money or won money, this may impact future decisions. It is unclear how past outcomes influence future decisions in humans, and how neural circuits encode present and past information. In this study, six human subjects performed a financial decision-making task while we recorded local field potentials from multiple brain structures. We constructed a model for each subject characterizing bets on each trial as a function of present and past information. The models suggest that some patients are more influenced by previous trial outcomes (i.e., previous return and risk) than others who stick to more fixed decision strategies. In addition, past return and present risk modulated with the activity in the cuneus; while present return and past risk modulated with the activity in the superior temporal gyrus and the angular gyrus, respectively. Our findings suggest that these structures play a role in decision-making beyond their classical functions by incorporating predictions and risks in humans' decision strategy, and provide new insight into how humans link their internal biases to decisions.

The Impact of Executive Functions and Emotional Intelligence on Iowa Gambling Task Performance: Focus on Right Frontal Lobe Damage

Objective

Decision-making in the Iowa Gambling Task (IGT) has been intensively studied regarding both the "hot" and "cold" components. The ventromedial prefrontal cortex is a key region involved in processing somatic marker information, though recent findings suggest dorsolateral regions are also important. The dorsolateral prefrontal cortex is also known as a substrate of executive functions-the cold component of decision-making. However, there is contradictory evidence about the role of executive functions, as well as the hot component of decision-making-emotional intelligence. Previous findings suggest that patients with right frontal lobe lesions find decision-making more problematic in IGT. The goal of this study is to replicate previous findings on IGT performance in patients with dorsolateral lesions compared to controls.

Methods

We obtained data from patients with right frontal lobe tumors (n = 12), localized in the dorsolateral prefrontal cortex, and healthy controls (n = 21) who undertook the IGT, Wisconsin Card Sorting Test (WCST), Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT), and D-KEFS Color-Word Interference Test.

Results

The performance in the IGT, WCST, and EI tests is impaired in the clinical group. At the subgroup level, we found patients had lower EI scores regarding the ability to use "emotions for thinking facilitation". However, we found an interaction between the EI scores regarding the ability "the perception and identification of emotions" and the performance on WCST only in the patient group.

Conclusion

This study raises the possibility of identifying components of EI which could be helpful in understanding the impairment of patients with right dorsolateral lesions.

The Effect of Losses Disguised as Wins and Near Misses in Electronic Gaming Machines: A Systematic Review

Near misses and losses disguised as wins have been of interest to gambling researchers and policymakers for many years (e.g., Griffiths in J Gambl Stud 9(2):101-120, 1993). This systematic literature review describes the behavioural, psychological, and psychobiological effects of near misses and losses disguised as wins (LDWs) in an effort to evaluate their precise influence on the player and to highlight areas requiring further investigation. A systematic search for relevant studies was conducted using Scopus, PubMed, PsycINFO, ProQuest Sociology databases, and the Gambling Research Exchange Ontario Knowledge Repository. A total of 51 (from an initial pool of 802) experimental peer-reviewed studies using human participants were found between 1991 and 2015. The systematic review revealed that near misses motivate continued play, but have varying effects on the emotional state or betting behaviour of the player. Near miss events were also shown to be associated with elevated skin conductance levels and diffuse activity across the brain, most consistently in areas processing reinforcement and reward. Re-examination of the studies of near misses events after classifying the type of game feedback suggested that the effectiveness of near misses is related to the phenomenology of a near miss itself rather than as a response to auditory or visual feedback provided by a slot machine. In contrast to near misses, the presence of LDWs was found to relate to an overestimation of how much a player is actually winning and was consistently viewed as an exciting event. The effect of LDWs appears to be driven by the presence of visuals and sounds most often associated with a true win. Practical implications and directions for future research are also discussed.

The neural basis of temporal individuation and its capacity limits in the human brain

Individuation refers to individuals' use of spatial and temporal properties to register objects as distinct perceptual events relative to other stimuli. Although behavioral studies have examined both spatial and temporal individuation, neuroimaging investigations have been restricted to the spatial domain and at relatively late stages of information processing. Here, we used univariate and multivoxel pattern analyses of functional MRI data to identify brain regions involved in individuating temporally distinct visual items and the neural consequences that arise when this process reaches its capacity limit (repetition blindness, RB). First, we found that regional patterns of blood-oxygen-level-dependent activity across the cortex discriminated between instances where repeated and nonrepeated stimuli were successfully individuated-conditions that placed differential demands on temporal individuation. These results could not be attributed to repetition suppression or other stimulus-related factors, task difficulty, regional activation differences, other capacity-limited processes, or artifacts in the data or analyses. Contrary to current theoretical models, this finding suggests that temporal individuation is supported by a distributed set of brain regions, rather than a single neural correlate. Second, conditions that reflect the capacity limit of individuation-instances of RB-lead to changes in the spatial patterns within this network, as well as amplitude changes in the left hemisphere premotor cortex, superior medial frontal cortex, anterior cingulate cortex, and bilateral parahippocampal place area. These findings could not be attributed to response conflict/ambiguity and likely reflect the core brain regions and mechanisms that underlie the capacity-limited process that gives rise to RB.NEW & NOTEWORTHY We present novel findings into the neural bases of temporal individuation and repetition blindness (RB)-the perceptual deficit that arises when this process reaches its capacity limit. Specifically, we found that temporal individuation is a widely distributed process in the brain and identified a number of candidate brain regions that appear to underpin RB. These findings enhance our understanding of how these fundamental perceptual processes are reflected in the human brain.

Insular and cingulate attenuation during decision making is associated with future transition to stimulant use disorder

AIMS

To understand processes placing individuals at risk for stimulant (amphetamine and cocaine) use disorder.

DESIGN

Longitudinal study.

SETTING

University of California, San Diego Department of Psychiatry, CA, USA.

PARTICIPANTS

Occasional stimulant users (OSU; n = 184) underwent a baseline clinical interview and a functional magnetic resonance imaging (fMRI) session. On the basis of a follow-up clinical interview completed 3 years later, OSU (n = 147) were then categorized as problem stimulant users (PSU: n = 36; those who developed stimulant use disorders in the interim) or desisted stimulant users (DSU: n = 74; those who stopped using). OSU who did not meet criteria for PSU or DSU (n = 37) were included in dimensional analyses.

MEASUREMENTS

fMRI blood oxygen level-dependent (BOLD) contrast percentage signal change from baseline collected during a Paper-Scissors-Rock task was examined during three decision-making conditions, those resulting in: (1) wins, (2) ties and (3) losses. These data were used as dependent variables in categorical analyses comparing PSU and DSU, as well as dimensional analyses including interim drug use as predictors, controlling for baseline drug use.

FINDINGS

PSU exhibited lower anterior cingulate, middle insula, superior temporal, inferior parietal, precuneus and cerebellum activation than DSU across all three conditions (significant brain clusters required > 19 neighboring voxels to exceed F_(1,108)  = 5.58, P < 0.01 two-tailed; all Cohen's d > 0.83). Higher interim marijuana use was linked to lower pre-central and superior temporal activation during choices resulting in wins (> 19 neighboring voxels to exceed t = 2.61, P < 0.01 two-tailed; R² change > 0.11).

CONCLUSIONS

Individuals who transition from stimulant use to stimulant use disorder appear to show alterations in neural processing of stimulus valuation and outcome monitoring, patterns also evident in chronic stimulant use disorder. Attenuated anterior cingulate and insular processing may constitute a high-risk neural processing profile, which could be used to calculate risk scores for individuals experimenting with stimulants.

Dissociable neural processes during risky decision-making in individuals with Internet-gaming disorder

Risk-taking is purported to be central to addictive behaviors. However, for Internet gaming disorder (IGD), a condition conceptualized as a behavioral addiction, the neural processes underlying impaired decision-making (risk evaluation and outcome processing) related to gains and losses have not been systematically investigated. Forty-one males with IGD and 27 healthy comparison (HC) male participants were recruited, and the cups task was used to identify neural processes associated with gain- and loss-related risk- and outcome-processing in IGD. During risk evaluation, the IGD group, compared to the HC participants, showed weaker modulation for experienced risk within the bilateral dorsolateral prefrontal cortex (DLPFC) (t = - 4.07; t = - 3.94; PFWE  < 0.05) and inferior parietal lobule (IPL) (t = - 4.08; t = - 4.08; PFWE  < 0.05) for potential losses. The modulation of the left DLPFC and bilateral IPL activation were negatively related to addiction severity within the IGD group (r = - 0.55; r = - 0.61; r = - 0.51; PFWE  < 0.05). During outcome processing, the IGD group presented greater responses for the experienced reward within the ventral striatum, ventromedial prefrontal cortex, and orbitofrontal cortex (OFC) (t = 5.04, PFWE  < 0.05) for potential gains, as compared to HC participants. Within the IGD group, the increased reward-related activity in the right OFC was positively associated with severity of IGD (r = 0.51, PFWE  < 0.05). These results provide a neurobiological foundation for decision-making deficits in individuals with IGD and suggest an imbalance between hypersensitivity for reward and weaker risk experience and self-control for loss. The findings suggest a biological mechanism for why individuals with IGD may persist in game-seeking behavior despite negative consequences, and treatment development strategies may focus on targeting these neural pathways in this population.

Visual Imagery and False Memory for Pictures: A Functional Magnetic Resonance Imaging Study in Healthy Participants

Background

Visual mental imagery might be critical in the ability to discriminate imagined from perceived pictures. Our aim was to investigate the neural bases of this specific type of reality-monitoring process in individuals with high visual imagery abilities.

Methods

A reality-monitoring task was administered to twenty-six healthy participants using functional magnetic resonance imaging. During the encoding phase, 45 words designating common items, and 45 pictures of other common items, were presented in random order. During the recall phase, participants were required to remember whether a picture of the item had been presented, or only a word. Two subgroups of participants with a propensity for high vs. low visual imagery were contrasted.

Results

Activation of the amygdala, left inferior occipital gyrus, insula, and precuneus were observed when high visual imagers encoded words later remembered as pictures. At the recall phase, these same participants activated the middle frontal gyrus and inferior and superior parietal lobes when erroneously remembering pictures.

Conclusions

The formation of visual mental images might activate visual brain areas as well as structures involved in emotional processing. High visual imagers demonstrate increased activation of a fronto-parietal source-monitoring network that enables distinction between imagined and perceived pictures.

Brain substrates of perceived spatial separation between speech sources under simulated reverberant listening conditions in schizophrenia

BACKGROUND

People with schizophrenia recognize speech poorly under multiple-people-talking (informational masking) conditions. In reverberant environments, direct-wave signals from a speech source are perceptually integrated with the source reflections (the precedence effect), forming perceived spatial separation (PSS) between different sources and consequently improving target-speech recognition against informational masking. However, the brain substrates underlying the schizophrenia-related vulnerability to informational masking and whether schizophrenia affects the unmasking effect of PSS are largely unknown.

METHOD

Using psychoacoustic testing and functional magnetic resonance imaging, respectively, the speech recognition under either the PSS or perceived spatial co-location (PSC) condition and the underlying brain substrates were examined in 20 patients with schizophrenia and 16 healthy controls.

RESULTS

Speech recognition was worse in patients than controls. Under the PSS (but not PSC) condition, speech recognition was correlated with activation of the superior parietal lobule (SPL), and target speech-induced activation of the SPL, precuneus, middle cingulate cortex and caudate significantly declined in patients. Moreover, the separation (PSS)-against-co-location (PSC) contrast revealed (1) activation of the SPL, precuneus and anterior cingulate cortex in controls, (2) suppression of the SPL and precuneus in patients, (3) activation of the pars triangularis of the inferior frontal gyrus and middle frontal gyrus in both controls and patients, (4) activation of the medial superior frontal gyrus in patients, and (5) impaired functional connectivity of the SPL in patients.

CONCLUSIONS

Introducing the PSS listening condition efficiently reveals both the brain substrates underlying schizophrenia-related speech-recognition deficits against informational masking and the schizophrenia-related neural compensatory strategy for impaired SPL functions.