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Elephanta Island near Mumbai is an important area for understanding the stratigraphic and structural framework of the Deccan flood basalt province in the tectonically disturbed Panvel flexure zone on the western Indian rifted margin. Elephanta exposes a west-dipping, 66−65 Ma sequence of tholeiitic lava flows and dykes. Geochemical correlations with the thick, horizontal, 66−65 Ma Western Ghats sequence to the east show that lava flows of the Khandala and Ambenali formations are present at Elephanta, with two lava flows probably being locally derived. The Elephanta tholeiites have experienced crystal fractionation and accumulation, particularly of olivine. They have eNd(t) ranging from +5.4 to −7.9 and (87Sr/86Sr)t from 0.70391 to 0.70784, with most tholeiites little contaminated by continental lithosphere, probably lower crust. Field and geochemical data indicate a normal fault along the central part of Elephanta with a 220 m downthrow, consistent with a domino-type block-faulted structure of Elephanta, and the surrounding area as previously known. Seventeen of the 20 analyzed Elephanta intrusions, striking ~N−S, belong to the Coastal dyke swarm of the western Deccan province. Several of these are probable feeders to the Ambenali Formation in the Western Ghats sequence, requiring reconsideration of the current view that the voluminous Wai Subgroup lavas of the Western Ghats were erupted without organized crustal extension. East−west-directed extensional strain was already active at 66−65 Ma along this future (62.5 Ma) rifted continental margin. A young (~62 Ma) ankaramite dyke on Elephanta Island is a probable feeder to the Powai ankaramite flow in the 62.5 Ma Mumbai sequence 20 km to the northwest.

Need states are internal states that arise from deprivation of crucial biological stimuli. They direct motivation, independently of external learning. Despite their separate origin, they interact with reward processing systems that respond to external stimuli. This article aims to illuminate the functioning of the needing system through the lens of active inference, a framework for understanding brain and cognition. We propose that need states exert a pervasive influence on the organism, which in active inference terms translates to a "pervasive surprise"-a measure of the distance from the organism's preferred state. Crucially, we define needing as an active inference process that seeks to reduce this pervasive surprise. Through a series of simulations, we demonstrate that our proposal successfully captures key aspects of the phenomenology and neurobiology of needing. We show that as need states increase, the tendency to occupy preferred states strengthens, independently of external reward prediction. Furthermore, need states increase the precision of states (stimuli and actions) leading to preferred states, suggesting their ability to amplify the value of reward cues and rewards themselves. Collectively, our model and simulations provide valuable insights into the directional and underlying influence of need states, revealing how this influence amplifies the wanting or liking associated with relevant stimuli., (© 2024 Massachusetts Institute of Technology. Published under a Creative Commons Attribution 4.0 International (CC BY 4.0) license.)

Miller et al. (2010) previously suggested that borderline pathology, vulnerable narcissism, and Factor 2 psychopathy share a common "Vulnerable Dark Triad" (VDT) core. The present study (N = 1,023 community participants) aims to test that hypothesis using exploratory and confirmatory bifactor analyses. We found support for a bifactor model that obtained satisfactory fits and other adequate validity indices, which included a general VDT factor and three group factors (Reckless, Entitled, Hiding). The general VDT factor was mostly saturated with borderline symptoms items reflecting self-hatred and worthlessness, which did not form a group factor; these results add to previous research suggesting that features of borderline pathology may represent the core of personality pathology. The three group factors had distinctive relationships with Dark Triad traits, pathological trait domains, and aggression. In contrast with the three group factors, the general VDT factor more strongly incremented the prediction of negative affectivity and hostility; the group factors more strongly incremented the prediction of grandiosity, egocentrism, callousness, Machiavellianism, and direct (physical/verbal) aggression. Alignment of the retained bifactor model with influent models of personality pathology and conceptual/methodological implications of the present results for research on the hypothesized VDT are discussed, as well as some clinical implications of the findings., (© 2023 The Authors. Scandinavian Journal of Psychology published by Scandinavian Psychological Associations and John Wiley & Sons Ltd.)

Previous research indicates that the anticipatory shame an individual feels at the prospect of taking a disgraceful action closely tracks the degree to which local audiences, and even foreign audiences, devalue those individuals who take that action. This supports the proposition that the shame system (a) defends the individual against the threat of being devalued, and (b) balances the competing demands of operating effectively yet efficiently. The stimuli events used in previous research were highly variable in their perceived disgracefulness, ranging in rated shame and audience devaluation from low (e.g., missing the target in a throwing game) to high (e.g., being discovered cheating on one's spouse). But how precise is the tracking of audience devaluation by the shame system? Would shame track devaluation for events that are similarly low (or high) in disgracefulness? To answer this question, we conducted a study with participants from the United States and India. Participants were assigned, between-subjects, to one of two conditions: shame or audience devaluation. Within-subjects, participants rated three low-variation sets of 25 scenarios each, adapted from Mu, Kitayama, Han, & Gelfand (2015), which convey (a) appropriateness (e.g., yelling at a rock concert), (b) mild disgracefulness (e.g., yelling on the metro), and (c) disgracefulness (e.g., yelling in the library), all presented un-blocked, in random order. Consistent with previous research, shame tracked audience devaluation across the high-variation superset of 75 scenarios, both within and between cultures. Critically, shame tracked devaluation also within each of the three sets. The shame system operates with high precision.

Adequate social functioning during childhood requires context-appropriate social decision-making. To make such decisions, children rely on their social norms, conceptualized as cognitive models of shared expectations. Since social norms are dynamic, children must adapt their models of shared expectations and modify their behavior in line with their social environment. This study aimed to investigate children's abilities to use social information to adapt their fairness norm and to identify the computational mechanism governing this process. Thirty children (7-11 years, M = 7.9 SD = 0.85, 11 girls) played the role of Responder in a modified version of the Ultimatum Game-a two-player game based on the fairness norm-in which they had to choose to accept or reject offers from different Proposers. Norm adaptation was assessed by comparing rejection rates before and after a conditioning block in which children received several low offers. Computational models were compared to test which best explains children's behavior during the game. Mean rejection rate decreased significantly after receiving several low offers suggesting that children have the ability to dynamically update their fairness norm and adapt to changing social environments. Model-based analyses suggest that this process involves the computation of norm-prediction errors. This is the first study on norm adaptation capacities in school-aged children that uses a computational approach. Children use implicit social information to adapt their fairness norm to changing environments and this process appears to be supported by a computational mechanism in which norm-prediction errors are used to update norms., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Morasse et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Sociomoral reasoning (SMR) is an essential component of social functioning allowing children to establish judgments based on moral criteria. The progressive emergence and complexification of SMR during childhood is thought to be underpinned by a range of characteristics and abilities present in the preschool years. Past studies have mostly examined concurrent associations between individual factors and SMR. Using a more comprehensive and predictive approach to identify early predictors of school-age SMR would contribute to a more complete picture of SMR development. This study aimed to investigate the contribution of four domains of preschool predictors to SMR at school-age: demographic (age, sex, parental education), cognitive (executive and sociocognitive functions), behavioral (internalizing and externalizing behaviors), and familial (parent-child interactions, parental stress) factors. Parents of 122 children 3 to 5 years (M = 3.70, SD = 0.66 years, 51% girls) completed questionnaires and children were administered executive and sociocognitive tasks. Parent-child interactions were assessed using an observational approach. SMR was measured four years later using the SoMoral task. A four-step hierarchical regression analysis revealed that executive functions and internalizing problems were significant independent predictors of SMR. These findings provide a more comprehensive understanding of the early precursors of SMR during childhood.

Consumption and its excesses are sometimes explained by imbalance of need or lack of control over "wanting." "Wanting" assigns value to cues that predict rewards, whereas "needing" assigns value to biologically significant stimuli that one is deprived of. Here we aimed at studying how the brain activation patterns related to value of "wanted" stimuli differs from that of "needed" stimuli using activation likelihood estimation neuroimaging meta-analysis approaches. We used the perception of a cue predicting a reward for "wanting" related value and the perception of food stimuli in a hungry state as a model for "needing" related value. We carried out separate, contrasts, and conjunction meta-analyses to identify differences and similarities between "wanting" and "needing" values. Our overall results for "wanting" related value show consistent activation of the ventral tegmental area, striatum, and pallidum, regions that both activate behavior and direct choice, while for "needing" related value, we found an overall consistent activation of the middle insula and to some extent the caudal-ventral putamen, regions that only direct choice. Our study suggests that wanting has more control on consumption and behavioral activation., (© 2022 The Authors. Brain and Behavior published by Wiley Periodicals LLC.)

Objectives Shame is a painful feeling that one feels when under the impression of having committed an offence or contravened to a personal or moral standard. Shame experiences are often intense and entail a global, negative self-evaluation; persons then feel like they are bad, weak, worthless, or deserving others' contempt. Some people are more prone to shame feelings. Although shame is not listed as a diagnostic criterion of borderline personality disorder (BPD) in the DSM-5, studies suggest that shame is an important feature in individuals with BPD. The aim of this study is to garner additional data to document shame proneness in individuals presenting with borderline symptomatology in the population from the Province of Quebec. Method Overall, 646 community adults from the Province of Quebec completed online the brief version of the Borderline Symptom List (BSL-23), measuring the severity of symptoms associated with BPD from a dimensional perspective, and to the Experience of Shame Scale (ESS), measuring shame proneness in various areas of a person's life. Participants were then compared on their shame scores after they were assigned to one of the four groups based on Kleindienst et al. (2020) classification of severity of borderline symptoms: (a) none or low symptoms (n = 173), (b) mild symptoms (n = 316), (c) moderate symptoms (n = 103), or (d) high, very high or extremely high symptoms (n = 54). Results Between-group differences were found with large effect sizes in all shame areas measured by the ESS, suggesting that shame feelings tend to be greater in persons presenting more borderline traits. Conclusion Results are discussed in a clinical perspective of BPD, emphasizing the importance of having shame as a clinical target in psychotherapy with these clients. Furthermore, our results raise conceptual questions regarding how to integrate shame in the assessment and treatment of BPD.

Individuals are faster at detecting threatening stimuli than neutral stimuli. While generally considered a rapid bottom-up response, this threat superiority effect is also modulated by top-down mechanisms known to rely on the dorsolateral prefrontal cortex (DLPFC). What remains unclear is whether the response is modulated only at later stages of processing, or whether rapid attention to threat itself is controlled in a top-down manner. To test this, we used repetitive transcranial magnetic stimulation (rTMS) to inhibit activity in the DLPFC, and measured EEG to index the immediate neural response to threat. Twenty participants attended two sessions where they performed a visual search task with threatening or neutral targets. Prior to this, they received 15 min of 1 Hz inhibitory or sham rTMS targeting the right DLPFC. We measured the impact of rTMS on the P1, a rapid visually-evoked potential that is modulated by attention. We found that threatening targets increased the amplitude of the P1 in the sham condition, but inhibition of the DLPFC abolished this increase. These results suggest that the neural signature of rapid attentional detection of threat, even at its earliest stage, is influenced in a top-down fashion by the right DLPFC., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Vachon and Lynam (2016) recently introduced a new measure of empathy, the Affective and Cognitive Measure of Empathy (ACME). Besides assessing the traditional dimensions of cognitive and affective empathy, the ACME includes an affective dissonance scale that covers "antiempathy," an important feature of the construct with prominent predictive value not included in other empathy measures. The aim of this study is to provide data on the French version of the ACME. A sample of 851 community-dwelling participants (59.4% female) completed online the ACME questionnaire along with other measures of empathy, dark and pathological personality traits, and aggression. The original ACME bifactor exploratory structural equation modeling structure (i.e., the three empathy dimensions of Cognitive, Affective Resonance, and Affective Dissonance with positive and negative wording items as method bifactors) was successfully reproduced with the French version. Furthermore, these scales displayed satisfying internal consistency coefficients, as well as good item properties according to Classical Test Theory. Convergent validity indices were also similar to those reported for the original English version, and scale scores reached full invariance across gender and proved to be partially invariant across language when comparing the present data to those from the original validation study. The French version of the ACME is well aligned with the original English version and offers a valuable alternative to French researchers and clinicians interested in measuring the various dimensions of empathy. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Recent overarching frameworks propose that various human social interactions are commonly supported by a set of fundamental neuropsychological processes, including social cognition, motivation, and cognitive control. However, it remains unclear whether brain networks implicated in these functional constructs are consistently engaged in diverse social interactions. Based on ample evidence from human brain imaging studies (342 contrasts, 7234 participants, 3328 foci), we quantitatively synthesized brain areas involved in broad domains of social interactions, including social interactions versus non-social contexts, positive/negative aspects of social interactions, social learning, and social norms. We then conducted brain network analysis on the ensuing brain regions and characterized the psychological function profiles of identified brain networks. Our findings revealed that brain regions consistently involved in diverse social interactions mapped onto default mode network, salience network, subcortical network and central executive network, which were respectively implicated in social cognition, motivation and cognitive control. These findings implicate a heuristic integrative framework to understand human social life from the perspective of component process and network integration., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Human behavior is framed by several social structures. In the present study, we focus on two of the most important determinants of social structures: social norms and political orientation. Social norms are implicit models of shared expectations about how people should behave in different social contexts. Although humans are very sensitive to violations in social norms, there are important individual differences in our sensitivity to these violations. The second concept this study focuses on is political orientation that is define by a continuum from left (liberal) to right (conservative). Individual political orientation has been found to be related to various individual traits, such as cognitive style or sensitivity to negative stimuli. Here, we propose to study the relation between sensitivity to social norm violation and political orientation. Participants completed a task presenting scenarios with different degrees of social norm violation and a questionnaire to measure their political opinions on economic and identity issues. Using hierarchical regressions, we show that individual differences in sensitivity to social norm violation are partly explained by political orientation, and more precisely by the identity axis. The more individuals have right-oriented political opinions, the more they are sensitive to social norm violation, even when multiple demographics variables are considered. Our results suggest that political orientation, especially according to identity issues, is a significant factor of individual differences in social norm processing., Competing Interests: The authors have declared that no competing interests exist.

Activity changes in dopaminergic neurons encode the ongoing discrepancy between expected and actual value of a stimulus, providing a teaching signal for a reward prediction process. Previous work comparing a cohort of long-term Zen meditators to controls demonstrated an attenuation of reward prediction signals to appetitive reward in the striatum. Using a cross-commodity design encompassing primary- and secondary-reward conditioning experiments, the present study asks the question of whether reward prediction signals are causally altered by mindfulness training in naïve subjects. Volunteers were randomly assigned to 8 weeks of mindfulness training (MT), active control training (CT), or a one-time mindfulness induction group (MI). We observed a decreased response to positive prediction errors in the putamen in the MT group compared to CT using both a primary and a secondary-reward experiment. Furthermore, the posterior insula showed greater activation to primary rewards, independently of their predictability, in the MT group, relative to CT and MI group. These results support the notion that increased attention to the present moment and its interoceptive features - a core component of mindfulness practice - may reduce predictability effects in reward processing, without dampening (in fact, enhancing) the response to the actual delivery of the stimulus.

Training and repeated exposure to odorants leads to enhanced olfactory sensitivity. So far, the efficacy of intensive olfactory training on olfactory function in a healthy population and its underlying neurobiological basis remain poorly known. This study investigated the effects of a 6-week intensive and well-controlled olfactory training on olfactory function and brain structure/neuroplasticity. Thirty-six healthy young individuals were recruited and randomly distributed in three groups: (1) 12 participants underwent daily intensive olfactory training of at least 20 min that included an (a) odor intensity classification task, an (b) odor quality classification task and an (c) target odor detection task, (2) 12 participants underwent an equivalent visual control training, and (3) 12 control individuals did not participate in any training. Before and after the training period, all participants performed a series of olfactory tests and those from groups 1 and 2 underwent structural magnetic resonance (MR) imaging, from which we obtained measures such as cortical thickness and tissue density. Participants improved in the respectively trained tasks throughout the 6-weeks training period. Those who underwent olfactory training improved general olfactory function compared to control participants, especially in odor identification, thus showing intramodal transfer. Further, MR imaging analysis revealed that olfactory training led to increased cortical thickness in the right inferior frontal gyrus, the bilateral fusiform gyrus and the right entorhinal cortex. This research shows that intensive olfactory training can generally improve olfactory function and that this improvement is associated with changes in the structure of olfactory processing areas of the brain., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Early childhood educational investment produces positive effects on cognitive and non-cognitive skills, health, and socio-economic success. However, the effects of such interventions on social decision-making later in life are unknown. We recalled participants from one of the oldest randomized controlled studies of early childhood investment-the Abecedarian Project (ABC)-to participate in well-validated interactive economic games that probe social norm enforcement and planning. We show that in a repeated-play ultimatum game, ABC participants who received high-quality early interventions strongly reject unequal division of money across players (disadvantageous or advantageous) even at significant cost to themselves. Using a multi-round trust game and computational modeling of social exchange, we show that the same intervention participants also plan further into the future. These findings suggest that high quality early childhood investment can result in long-term changes in social decision-making and promote social norm enforcement in order to reap future benefits.

Social comparison is ubiquitous across human societies with dramatic influence on people's well-being and decision making. Downward comparison (comparing to worse-off others) and upward comparison (comparing to better-off others) constitute two types of social comparisons that produce different neuropsychological consequences. Based on studies exploring neural signatures associated with downward and upward comparisons, the current study utilized a coordinate-based meta-analysis to provide a refinement of understanding about the underlying neural architecture of social comparison. We identified consistent involvement of the ventral striatum and ventromedial prefrontal cortex in downward comparison and consistent involvement of the anterior insula and dorsal anterior cingulate cortex in upward comparison. These findings fit well with the "common-currency" hypothesis that neural representations of social gain or loss resemble those for non-social reward or loss processing. Accordingly, we discussed our findings in the framework of general reinforcement learning (RL) hypothesis, arguing how social gain/loss induced by social comparisons could be encoded by the brain as a domain-general signal (i.e., prediction errors) serving to adjust people's decisions in social settings. Although the RL account may serve as a heuristic framework for the future research, other plausible accounts on the neuropsychological mechanism of social comparison were also acknowledged. Hum Brain Mapp 39:440-458, 2018. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)

As models of shared expectations, social norms play an essential role in our societies. Since our social environment is changing constantly, our internal models of it also need to change. In humans, there is mounting evidence that neural structures such as the insula and the ventral striatum are involved in detecting norm violation and updating internal models. However, because of methodological challenges, little is known about the possible involvement of midbrain structures in detecting norm violation and updating internal models of our norms. Here, we used high-resolution cardiac-gated functional magnetic resonance imaging and a norm adaptation paradigm in healthy adults to investigate the role of the substantia nigra/ventral tegmental area (SN/VTA) complex in tracking signals related to norm violation that can be used to update internal norms. We show that the SN/VTA codes for the norm's variance prediction error (PE) and norm PE with spatially distinct regions coding for negative and positive norm PE. These results point to a common role played by the SN/VTA complex in supporting both simple reward-based and social decision making., (© The Author (2017). Published by Oxford University Press.)

Motor representations in the human mirror neuron system are tuned to respond to specific observed actions. This ability is widely believed to be influenced by genetic factors, but no study has reported a genetic variant affecting this system so far. One possibility is that genetic variants might interact with visuomotor associative learning to configure the system to respond to novel observed actions. In this perspective, we conducted a candidate gene study on the Brain-derived neurotrophic factor (BDNF) Val66Met polymorphism, a genetic variant linked to motor learning in regions of the mirror neuron system, and tested the effect of this polymorphism on motor facilitation and visuomotor associative learning. In a single-pulse TMS study carried on 16 Met (Val/Met and Met/Met) and 16 Val/Val participants selected from a large pool of healthy volunteers, Met participants showed significantly less muscle-specific corticospinal sensitivity during action observation, as well as reduced visuomotor associative learning, compared to Val homozygotes. These results are the first evidence of a genetic variant tuning sensitivity to action observation and bring to light the importance of considering the intricate relation between genetics and associative learning in order to further understand the origin and function of the human mirror neuron system.

Transcranial magnetic stimulation (TMS) studies have shown that observing an action induces muscle-specific changes in corticospinal excitability. From a signal detection theory standpoint, this pattern can be related to sensitivity, which here would measure the capacity to distinguish between two action observation conditions. In parallel to these TMS studies, action observation has also been linked to behavioral effects such as motor priming and interference. It has been hypothesized that behavioral markers of action observation could be related to TMS markers and thus represent a potentially cost-effective mean of assessing the functioning of the action-perception system. However, very few studies have looked at possible relationships between these two measures. The aim of this study was to investigate if individual differences in sensitivity to action observation could be related to the behavioral motor priming and interference effects produced by action observation. To this end, 14 healthy participants observed index and little finger movements during a TMS task and a stimulus-response compatibility task. Index muscle displayed sensitivity to action observation, and action observation resulted in significant motor priming+interference, while no significant effect was observed for the little finger in both task. Nevertheless, our results indicate that the sensitivity measured in TMS was not related to the behavioral changes measured in the stimulus-response compatibility task. Contrary to a widespread assumption, the current results indicate that individual differences in physiological and behavioral markers of action observation may be unrelated. This could have important impacts on the potential use of behavioral markers in place of more costly physiological markers of action observation in clinical settings.

The habenula is a hub for cognitive and emotional signals that are relayed to the aminergic centers in the midbrain and, thus, plays an important role in goal-oriented behaviors. Although it is well described in rodents and non-human primates, the habenula functional network remains relatively uncharacterized in humans, partly because of the methodological challenges associated with the functional magnetic resonance imaging of small structures in the brain. Using high-resolution cardiac-gated resting state imaging in healthy humans and precisely identifying each participants' habenula, we show that the habenula is functionally coupled with the insula, parahippocampus, thalamus, periaqueductal grey, pons, striatum and substantia nigra/ventral tegmental area complex. Furthermore, by separately examining and comparing the functional maps from the left and right habenula, we provide the first evidence of an asymmetry in the functional connectivity of the habenula in humans. Hum Brain Mapp 37:2602-2615, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc., (© 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.)

Empathy is an important driver of human social behaviors and presents genetic roots that have been studied in neuroimaging using the intermediate phenotype approach. Notably, the Val66Met polymorphism of the Brain-derived neurotrophic factor (BDNF) gene has been identified as a potential target in neuroimaging studies based on its influence on emotion perception and social cognition, but its impact on self-reported empathy has never been documented. Using a neurogenetic approach, we investigated the association between the BDNF Val66Met polymorphism and self-reported empathy (Davis' Interpersonal Reactivity Index; IRI) in a sample of 110 young adults. Our results indicate that the BDNF genotype is significantly associated with the linear combination of the four facets of the IRI, one of the most widely used self-reported empathy questionnaire. Crucially, the effect of BDNF Val66Met goes beyond the variance explained by two polymorphisms of the oxytocin transporter gene previously associated with empathy and its neural underpinnings (OXTR rs53576 and rs2254298). These results represent the first evidence suggesting a link between the BDNF gene and self-reported empathy and warrant further studies of this polymorphism due to its potential clinical significance.

Emotion perception has been extensively studied in cognitive neurosciences and stands as a promising intermediate phenotype of social cognitive processes and psychopathologies. Exciting imaging genetic studies have recently identified genetic and epigenetic variants affecting brain responses during emotion perception tasks, but characterizing how these variants interact and relate to higher-order cognitive processes remains a challenge. Here, we integrate works in parallel fields and propose a new psychophysical conceptualization to address this issue. This approach proposes to consider genetic variants as 'filters' of perceptual information that can interact to shape different perceptual profiles. Importantly, these perceptual profiles can be precisely described and compared between multivariate genetic groups using a new psychophysical method. Crucially, this approach represents a potentially powerful novel tool to address gene-by-gene and gene-by-environment interactions, and provides a new cognitive perspective to link social perceptive and social cognitive processes in the context of psychiatric disorders.

We show computational evidence that ground-state moderately strong hydroxyarenes (Ar-OH, pKa ∼ 0) dissociate by forming an ion-pair intermediate that lives for 3-5 ps. The concentration of this intermediate is approximately 2 times smaller than that of the un-ionized acid at pH ∼ 0.6 and is characterized by average C-O bond lengths (1.30 Å) that are intermediate between those of un-ionized (1.29 Å) and fully dissociated (1.34 Å) species. During the lifetime of the ion-pair intermediate the excess proton fluctuates between the oxygen atom of the phenolic moiety and those of water molecules in the first and second solvation shells on a subpicosecond time scale (∼100-300 fs).

Motor imagery (MI) or the mental simulation of action is now increasingly being studied using neuroimaging techniques such as positron emission tomography and functional magnetic resonance imaging. The booming interest in capturing the neural underpinning of MI has provided a large amount of data which until now have never been quantitatively summarized. The aim of this activation likelihood estimation (ALE) meta-analysis was to provide a map of the brain structures involved in MI. Combining the data from 75 papers revealed that MI consistently recruits a large fronto-parietal network in addition to subcortical and cerebellar regions. Although the primary motor cortex was not shown to be consistently activated, the MI network includes several regions which are known to play a role during actual motor execution. The body part involved in the movements, the modality of MI and the nature of the MI tasks used all seem to influence the consistency of activation within the general MI network. In addition to providing the first quantitative cortical map of MI, we highlight methodological issues that should be addressed in future research., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Purpose: A new noninvasive laser Doppler flowmetry (LDF) probe (one emitting fiber surrounded by a ring of eight collecting fibers, 1-mm interaxis distance) was tested for its sensitivity to assess the retinal/choroidal blood flow variations in response to hypercapnia, hyperoxia, diverse vasoactive agents and following retinal arteries photocoagulation in the rat., Materials and Methods: After pupil dilation, a LDF probe was placed in contact to the cornea of anesthetized rats in the optic axis. Hypercapnia and hyperoxia were induced by inhalation of CO(2) (8% in medical air) and O(2) (100%) while pharmacological agents were injected intravitreously. The relative contribution of the choroidal circulation to the LDF signal was estimated after retinal artery occlusion by photocoagulation., Results: Blood flow was significantly increased by hypercapnia (18%), adenosine (14%) and sodium nitroprusside (16%) as compared to baseline values while it was decreased by hyperoxia (-8%) and endothelin-1 (-11%). Photocoagulation of retinal arteries significantly decreased blood flow level (-45%)., Conclusions: Although choroidal circulation most likely contributes to the LDF signal in this setting, the results demonstrate that LDF represents a suitable in vivo noninvasive technique to monitor online relative reactivity of retinal perfusion to metabolic or pharmacological challenge. This technique could be used for repeatedly assessing blood flow reactivity in rodent models of ocular diseases.

Empathy is a multi-dimensional concept allowing humans to understand the emotions of others and respond adaptively from a social perspective. This mental process, essential to social interactions, has attracted the attention of many scholars from different fields of study but the blooming interest for empathy in cognitive neurosciences has rekindled this interest. This paper reviews the growing literature stemming from studies using brain stimulation techniques that have investigated directly or indirectly the different components of empathy, including resonance, self-other discrimination, and mentalizing. Some studies have also ventured toward the modulation of this complex process and toward the investigation of different components in populations that show reduced empathic skills. We argue that brain stimulation techniques have the potential to make a unique contribution to the field of empathy research with their exclusive capacity, compared to other brain imaging techniques, to modulate the neural systems involved in the distinct components of this process. Provided the development of innovative ecological paradigms that will put people in actual social interactions as well as comprehensive and adaptive models that can integrate research from different domains, the ultimate goal of this research domain is to devise protocols that can modulate empathy in people with developmental, neurological and psychiatric disorders., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The vasoactive kinin B₁ receptor (B₁R) is overexpressed in the retina of diabetic rats in response to hyperglycemia and oxidative stress. The aim of the present study was to determine whether B₁R could contribute to the early retinal blood flow changes occurring in diabetes. Male Wistar rats were rendered diabetic with a single i.p. injection of Streptozotocin (STZ) and studied 4 days or 6 weeks after diabetes induction. The presence of B₁R in the retina was confirmed by Western blot. The impact of oral administration of the B₁R selective antagonist SSR240612 (10mg/kg) was measured on alteration of retinal perfusion in awake diabetic rats by quantitative autoradiography. Data showed that B₁R was upregulated in the STZ-diabetic retina at 4 days and 6 weeks. Retinal blood flow was not altered in 4-day diabetic rats compared with age-matched controls but was significantly decreased following SSR240612 treatment. In 6-week diabetic rats, retinal blood flow was markedly reduced compared to control rats and SSR240612 did not further decrease the blood flow. These results suggest that B₁R is upregulated in STZ-diabetic retina and has a protective compensatory role on retinal microcirculation at 4 days but not at 6 weeks following diabetes induction., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

It is generally considered that hand amputation changes primary motor cortex (M1) stump muscle representations. Transcranial magnetic stimulation (TMS) studies show that the corticospinal excitability of a stump muscle and its homologous muscle on the intact side is not equivalent, and that the resting level of excitability is higher in the stump muscle. Since changes in M1 stump muscle map characteristics (e.g., size and location) are identified by comparing stump and intact muscle maps, such changes might reflect between-side differences in corticospinal excitability rather than a true reorganization of the stump muscle's map. In eight above-elbow amputees we used TMS to map the M1 representation of a stump muscle and its homologous muscle on the intact side during rest and contraction. Importantly, the same relative stimulation intensity was used to construct each map; stimulation was performed at 120% of the motor threshold of each muscle (intact/amputated limb) measured in each condition (rest/active contraction). Resting motor threshold was lower in the stump muscle, but active motor thresholds did not differ. Motor-evoked potential amplitudes increased between the rest and muscle contraction conditions, but this increase was smaller for the stump muscle because its at-rest corticospinal excitability was higher than that of the intact muscle. When the between-side difference in excitability was considered no interhemispheric difference was found for map areas or for their medio-lateral locations. The present results challenge the view that after an upper limb amputation the stump representation moves laterally and occupies a larger M1 territory., (Copyright © 2010 Wiley-Liss, Inc.)

The coupling process between observed and performed actions is thought to be performed by a fronto-parietal perception-action system including regions of the inferior frontal gyrus and the inferior parietal lobule. When investigating the influence of the movements' characteristics on this process, most research on action observation has focused on only one particular variable even though the type of movements we observe can vary on several levels. By manipulating the visual perspective, transitivity and meaningfulness of observed movements in a functional magnetic resonance imaging study we aimed at investigating how the type of movements and the visual perspective can modulate brain activity during action observation in healthy individuals. Importantly, we used an active observation task where participants had to subsequently execute or imagine the observed movements. Our results show that the fronto-parietal regions of the perception action system were mostly recruited during the observation of meaningless actions while visual perspective had little influence on the activity within the perception-action system. Simultaneous investigation of several sources of modulation during active action observation is probably an approach that could lead to a greater ecological comprehension of this important sensorimotor process.

Observation of hand movements has been repeatedly demonstrated to increase the excitability of the motor cortical representation of the hand. Little attention, however, has been devoted to its effect on somatosensory processing. Movement execution is well known to decrease somatosensory cortical excitability, a phenomenon termed 'gating'. As executed and observed actions share common cortical representations, we hypothesized that action observation (hand movements) should also modulate the cortical response to sensory stimulation of the hand. Seventeen healthy subjects participated in these experiments in which electroencephalographic (EEG) recordings of the somatosensory steady-state response (SSSR) were obtained. The SSSR provides a continuous measure of somatosensory processing. Recordings were made during a baseline condition and five observation conditions in which videos showed either a: (1) hand action; (2) passive stimulation of a hand; (3) static hand; (4) foot action; or (5) static object. The method employed consisted of applying a continuous 25 Hz vibratory stimulation to the index finger during the six conditions and measuring potential gating effects in the SSSR within the 25 Hz band (corresponding to the stimulation frequency). A significant effect of condition was found over the contralateral parietal cortex. Observation of hand actions resulted in a significant gating effect when compared to baseline (average gating of 22%). Observation of passive touch of the hand also gated the response (17% decrease). In conclusion, the results show that viewing a hand performing an action or being touched interferes with the processing of somatosensory information arising from the hand.

Quantitative and regional measurement of retinal blood flow in rodents is of prime interest for the investigation of regulatory mechanisms of ocular circulation in physiological and pathological conditions. In this study, a quantitative autoradiographic method using N-isopropyl-p-(14)C-iodoamphetamine ([(14)C]-IMP), a diffusible radioactive tracer, was evaluated for its ability to detect changes in retinal blood perfusion during hypercapnia. Findings were compared to cerebral blood flow values measured simultaneously. Hypercapnia was induced in awaken Wistar rats by inhalation of 5% or 8% CO(2) in medical air for 5 min. [(14)C]-IMP (100 microCi/kg) was injected in the femoral vein over a 30 s period and the rats were sacrificed 2 min later. Blood flow was calculated from whole-mount retinae and 20 microm thick brain sections in discrete regions of interest by quantitative autoradiography or from digested samples of retina and brain by liquid scintillation counting. Retinal blood flow values measured with quantitative and regional autoradiography were higher in the central (108 +/- 20 ml/100 g/min) than in peripheral (84 +/- 15 ml/100 g/min) retina. These values were within the same range as cortical blood flow values (97 +/- 4 ml/100 g/min). The retinal blood flow values obtained on whole-mount retinae were validated by the sampling method. Hypercapnia significantly increased overall blood flow in the retina (24-53%) with a maximal augmentation in the peripheral region and in the brain (22-142%). The changes were stronger in the brain compared to retina (p = 0.016). These results demonstrate that retinal blood flow can be quantified using [(14)C]-IMP and compared with cerebral blood flow. This technique is a powerful tool to study how retinal blood flow is regulated in different regions of the rat retina.