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Mindfulness meditation has been shown to promote emotional stability. Moreover, during the processing of aversive and self-referential stimuli, mindful awareness is associated with reduced medial prefrontal cortex (MPFC) activity, a central default mode network (DMN) component. However, it remains unclear whether mindfulness practice influences functional connectivity between DMN regions and, if so, whether such impact persists beyond a state of meditation. Consequently, this study examined the effect of extensive mindfulness training on functional connectivity within the DMN during a restful state. Resting-state data were collected from 13 experienced meditators (with over 1000 h of training) and 11 beginner meditators (with no prior experience, trained for 1 week before the study) using functional magnetic resonance imaging (fMRI). Pairwise correlations and partial correlations were computed between DMN seed regions' time courses and were compared between groups utilizing a Bayesian sampling scheme. Relative to beginners, experienced meditators had weaker functional connectivity between DMN regions involved in self-referential processing and emotional appraisal. In addition, experienced meditators had increased connectivity between certain DMN regions (e.g. dorso-medial PFC and right inferior parietal lobule), compared to beginner meditators. These findings suggest that meditation training leads to functional connectivity changes between core DMN regions possibly reflecting strengthened present-moment awareness.

There is mounting evidence that mindfulness meditation is beneficial for the treatment of mood and anxiety disorders, yet little is known regarding the neural mechanisms through which mindfulness modulates emotional responses. Thus, a central objective of this functional magnetic resonance imaging study was to investigate the effects of mindfulness on the neural responses to emotionally laden stimuli. Another major goal of this study was to examine the impact of the extent of mindfulness training on the brain mechanisms supporting the processing of emotional stimuli. Twelve experienced (with over 1000 h of practice) and 10 beginner meditators were scanned as they viewed negative, positive, and neutral pictures in a mindful state and a non-mindful state of awareness. Results indicated that the Mindful condition attenuated emotional intensity perceived from pictures, while brain imaging data suggested that this effect was achieved through distinct neural mechanisms for each group of participants. For experienced meditators compared with beginners, mindfulness induced a deactivation of default mode network areas (medial prefrontal and posterior cingulate cortices) across all valence categories and did not influence responses in brain regions involved in emotional reactivity during emotional processing. On the other hand, for beginners relative to experienced meditators, mindfulness induced a down-regulation of the left amygdala during emotional processing. These findings suggest that the long-term practice of mindfulness leads to emotional stability by promoting acceptance of emotional states and enhanced present-moment awareness, rather than by eliciting control over low-level affective cerebral systems from higher-order cortical brain regions. These results have implications for affect-related psychological disorders., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Recent advances in power spectral analysis of electroencephalography (EEG) signals and brain-computer interface (BCI) technology may significantly contribute to the development of psychoneurotherapies. The goal of this study was to measure the effect of a psychoneurotherapy on brain source generators of abnormal EEG activity in individuals with major depressive disorder (MDD). Thirty participants with unipolar MDD were recruited in the community. The proposed psychoneurotherapy was developed based on the relationship between the localization of abnormal EEG activity and depressive symptomatology. Brain electromagnetic abnormalities in MDD were identified with low resolution brain electromagnetic tomography (LORETA) and a normative EEG database. Localization of brain changes after treatment was assessed through the standardized version of LORETA (sLORETA). Before treatment, excessive high-beta (18-30 Hz) activity was noted in several brain regions located in the fronto-temporal regions. After treatment, only participants who successfully normalized EEG activity in cortico-limbic/paralimbic regions could be considered in clinical remission. In these regions, significant correlations were found between the percentage of change of depressive symptoms and the percentage of reduction in high-beta activity. These results suggest that the normalization of high-beta activity in cortico-limbic/paralimbic regions can be associated with a significant reduction of depressive symptoms.

Aim: To measure brain activity in near-death experiencers during a meditative state., Methods: In two separate experiments, brain activity was measured with functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) during a Meditation condition and a Control condition. In the Meditation condition, participants were asked to mentally visualize and emotionally connect with the "being of light" allegedly encountered during their "near-death experience". In the Control condition, participants were instructed to mentally visualize the light emitted by a lamp., Results: In the fMRI experiment, significant loci of activation were found during the Meditation condition (compared to the Control condition) in the right brainstem, right lateral orbitofrontal cortex, right medial prefrontal cortex, right superior parietal lobule, left superior occipital gyrus, left anterior temporal pole, left inferior temporal gyrus, left anterior insula, left parahippocampal gyrus and left substantia nigra. In the EEG experiment, electrode sites showed greater theta power in the Meditation condition relative to the Control condition at FP1, F7, F3, T5, P3, O1, FP2, F4, F8, P4, Fz, Cz and Pz. In addition, higher alpha power was detected at FP1, F7, T3 and FP2, whereas higher gamma power was found at FP2, F7, T4 and T5., Conclusions: The results indicate that the meditative state was associated with marked hemodynamic and neuroelectric changes in brain regions known to be involved either in positive emotions, visual mental imagery, attention or spiritual experiences.

Functional neuroimaging studies have shown that romantic love and maternal love are mediated by regions specific to each, as well as overlapping regions in the brain's reward system. Nothing is known yet regarding the neural underpinnings of unconditional love. The main goal of this functional magnetic resonance imaging study was to identify the brain regions supporting this form of love. Participants were scanned during a control condition and an experimental condition. In the control condition, participants were instructed to simply look at a series of pictures depicting individuals with intellectual disabilities. In the experimental condition, participants were instructed to feel unconditional love towards the individuals depicted in a series of similar pictures. Significant loci of activation were found, in the experimental condition compared with the control condition, in the middle insula, superior parietal lobule, right periaqueductal gray, right globus pallidus (medial), right caudate nucleus (dorsal head), left ventral tegmental area and left rostro-dorsal anterior cingulate cortex. These results suggest that unconditional love is mediated by a distinct neural network relative to that mediating other emotions. This network contains cerebral structures known to be involved in romantic love or maternal love. Some of these structures represent key components of the brain's reward system.

Background: Little is known about the specific contribution of serotonin (5-HT) to the neurobiology of emotion and mood in healthy people. In an exploratory study, we sought to investigate the effect of rapid and sustained changes of emotional state on the trapping of 11C-labelled alpha-methyl-L-tryptophan (11C-alphaMtrp) used as a proxy of 5-HT synthesis, using positron emission tomography (PET)., Method: In a within-subject repeated-measure design, participants recalled autobiographical memories to self-induce sadness, happiness and a neutral emotional state during scanning to measure brain trapping of 11C-alphaMtrp. Three separate scan acquisitions, counterbalanced for order across subjects, took place at the McConnell Brain Imaging Center, Montréal., Results: Whole brain analysis revealed positive and negative correlations between experienced levels of emotions and 11C-alphaMtrp trapping in the right anterior cingulate cortex., Conclusion: These findings point to a mechanism whereby state-related changes in a proxy of 5-HT synthesis underscore aspects of the self-regulation of normal mood.

This article reviews neuroimaging studies of conscious and voluntary regulation of various emotional states (sexual arousal, sadness, negative emotion). The results of these studies show that metacognition and cognitive recontextualization selectively alters the way the brain processes and reacts to emotional stimuli. Neuroimaging studies of the effect of psychotherapy in patients suffering from diverse forms of psychopathology (obsessive-compulsive disorder, panic disorder, unipolar major depressive disorder, social phobia, spider phobia, borderline personality) are also examined. The results of these studies indicate that the mental functions and processes involved in diverse forms of psychotherapy exert a significant influence on brain activity. Neuroimaging investigations of the placebo effect in healthy individuals (placebo analgesia, psychostimulant expectation) and patients with Parkinson's disease or unipolar major depressive disorder are also reviewed. The results of these investigations demonstrate that beliefs and expectations can markedly modulate neurophysiological and neurochemical activity in brain regions involved in perception, movement, pain, and various aspects of emotion processing. Collectively, the findings of the neuroimaging studies reviewed here strongly support the view that the subjective nature and the intentional content (what they are "about" from a first-person perspective) of mental processes (e.g., thoughts, feelings, beliefs, volition) significantly influence the various levels of brain functioning (e.g., molecular, cellular, neural circuit) and brain plasticity. Furthermore, these findings indicate that mentalistic variables have to be seriously taken into account to reach a correct understanding of the neural bases of behavior in humans. An attempt is made to interpret the results of these neuroimaging studies with a new theoretical framework called the Psychoneural Translation Hypothesis.

Two functional magnetic resonance imaging (fMRI) experiments were undertaken to measure the effect of neurofeedback training (NFT), in AD/HD children, on the neural substrates of selective attention and response inhibition. Twenty unmedicated AD/HD children participated to these experiments. Fifteen children were randomly assigned to the Experimental (EXP) group whereas the other five children were randomly assigned to the Control (CON) group. Only subjects in the EXP group underwent NFT. EXP subjects were trained to enhance the amplitude of the SMR (12-15 Hz) and beta 1 activity (15-18 Hz), and decrease the amplitude of theta activity (4-7 Hz). Subjects from both groups were scanned one week before the beginning of NFT (Time 1) and 1 week after the end of NFT (Time 2), while they performed a "Counting Stroop" task (Experiment 1) and a Go/No-Go task (Experiment 2). At Time 1, in both groups, the Counting Stroop task was associated with significant activation in the left superior parietal lobule. For the Go/No-Go task, no significant activity was detected in the EXP and CON groups. At Time 2, in both groups, the Counting Stroop task was associated with significant activation of the left superior parietal lobule. This time, however, there were significant loci of activation, in the EXP group, in the right ACC, left caudate nucleus, and left substantia nigra. No such activation loci were seen in CON subjects. For the Go/No-Go task, significant loci of activation were noted, in the EXP group, in the right ventrolateral prefrontal cortex, right ACcd, left thalamus, left caudate nucleus, and left substantia nigra. No significant activation of these brain regions was measured in CON subjects. These results suggest that NFT has the capacity to functionally normalize the brain systems mediating selective attention and response inhibition in AD/HD children.

The aim of this functional magnetic resonance imaging (fMRI) study was to compare regional brain activity in schizophrenia subjects with (FA+) and without (FA-) flat affect during the viewing of emotionally negative pictures. Thirteen FA+ subjects and 11 FA- subjects were scanned while being presented with a series of emotionally negative and neutral pictures. Experientially, the viewing of the negative pictures induced a negative emotional state whose intensity was significantly greater in the FA- group than in the FA+ group. Neurally, the Negative minus Neutral contrast revealed, in the FA- group, significant loci of activation in the midbrain, pons, anterior cingulate cortex, insula, ventrolateral orbitofrontal cortex, anterior temporal pole, amygdala, medial prefrontal cortex, and extrastriate visual cortex. In the FA+ group, this contrast produced significant loci of activation in the midbrain, pons, anterior temporal pole, and extrastriate visual cortex. When the brain activity measured in the FA+ group was subtracted from that measured in the FA- group, only the lingual gyrus was significantly activated. Perhaps in FA+ subjects an amygdaloid malfunction rendered the amygdala unable to correctly evaluate the emotional meaning of the pictures presented, thus preventing effective connectivity linking the amygdala to the brain regions implicated in the physiological and experiential dimensions of emotion. Alternatively, a disturbance of effective connectivity in the neural networks linking the midbrain and the medial prefrontal system may have been responsible for the quasi absence of emotional reaction in FA+ subjects, and the abnormal functioning of the medial prefrontal cortex and anterior cingulate cortex in the FA+ group.

Neuropsychological research on the neural basis of behaviour generally posits that brain mechanisms will ultimately suffice to explain all psychologically described phenomena. This assumption stems from the idea that the brain is made up entirely of material particles and fields, and that all causal mechanisms relevant to neuroscience can therefore be formulated solely in terms of properties of these elements. Thus, terms having intrinsic mentalistic and/or experiential content (e.g. 'feeling', 'knowing' and 'effort') are not included as primary causal factors. This theoretical restriction is motivated primarily by ideas about the natural world that have been known to be fundamentally incorrect for more than three-quarters of a century. Contemporary basic physical theory differs profoundly from classic physics on the important matter of how the consciousness of human agents enters into the structure of empirical phenomena. The new principles contradict the older idea that local mechanical processes alone can account for the structure of all observed empirical data. Contemporary physical theory brings directly and irreducibly into the overall causal structure certain psychologically described choices made by human agents about how they will act. This key development in basic physical theory is applicable to neuroscience, and it provides neuroscientists and psychologists with an alternative conceptual framework for describing neural processes. Indeed, owing to certain structural features of ion channels critical to synaptic function, contemporary physical theory must in principle be used when analysing human brain dynamics. The new framework, unlike its classic-physics-based predecessor, is erected directly upon, and is compatible with, the prevailing principles of physics. It is able to represent more adequately than classic concepts the neuroplastic mechanisms relevant to the growing number of empirical studies of the capacity of directed attention and mental effort to systematically alter brain function.

This study investigated changes in cerebral activation related to emotion processing in schizophrenia patients with blunted or flat affect (FA+) during treatment with quetiapine. Using functional magnetic resonance imaging (fMRI), brain activation in 12 FA+ schizophrenia patients during passive viewing of sad film excerpts was studied before and after a median of 5.5-months treatment with quetiapine. Random-effects 'paired sample t-test' analyses of brain activation before quetiapine (contrast=sad-neutral, before-after) revealed significant activation in the brainstem (pons, medulla). After quetiapine, the same contrast showed significant prefrontal activation (BA 9, 10 and 11). Activation of key prefrontal areas involved in emotion processing and significant symptoms improvement as measured by the subjective rating scale and PANSS suggests the potential effect of quetiapine in improving blunted affect related symptoms (i.e., passive withdrawal, emotional withdrawal, social avoidance) in schizophrenia.

Background: Brain morphology and physiological measures in schizophrenia have yielded inconsistent results. This may be due in part to difficulties in ascertaining precisely to what degree each measure deviates from its genetically and environmentally determined potential level. We attempted to surmount this problem in a paradigm involving monozygotic twin pair discordant for schizophrenia. In this paradigm, the difference score and reaction time between the unaffected member and affected member of a twin pair should represent the degree of pathologic involvement irrespective of actual level., Method: We investigated, using fMRI, the neural substrate underlying encoding and retrieval of aversive and neutral IAPS pictures., Results: An ANOVA on reaction time (RT) between schizophrenia patient (J) and normal sister (D) significant difference, (F = 5.2, p < or = .02) for J had less RT than D. Conversely, the ANOVA for the correct pictures retrieved was insignificant (F = 1.8, p < or = .2). When the brain activity associated with the encoding and retrieval of the aversive pictures was subtracted (J-D and D-J) from that associated with the neutral ones, significant loci of activation were found. During encoding: for J-D the right fusiform gyrus was significantly activated (p < .0001) and for D-J the orbitofrontal cortex was significantly activated (p < .05). During retrieval: for J-D the right anterior cingulate (p < .0001) was activated and the dorsolateral prefrontal cortex (p < .002). For D-J only the cerebellum showed activation (p < .0001)., Conclusion: Results indicated subtle attenuations in some aspects of memory, thus providing another evidence for cognitive markers of a genetic component in schizophrenia. New approaches in neuropsychiatry-based on genetic methodologies should further define the cerebral physiology responsible for schizophrenia.

The purpose of the present study was to compare the brain regions and systems that subserve lexical and sublexical processes in reading. In order to do so, three types of tasks were used: (i). silent reading of very high frequency regular words (lexical task); (ii). silent reading of nonwords (sublexical task); and, (iii). silent reading of very low frequency regular words (sublexical task). All three conditions were contrasted with a visual/phonological baseline condition. The lexical condition engaged primarily an area at the border of the left angular and supramarginal gyri. Activation found in this region suggests that this area may be involved in mapping orthographic-to-phonological whole word representations. Both sublexical conditions elicited significantly greater activation in the left inferior prefrontal gyrus. This region is thought to be associated with sublexical processes in reading such as grapheme-to-phoneme conversion, phoneme assembly and underlying verbal working memory processes. Activation in the left IFG was also associated with left superior and middle temporal activation. These areas are thought to be functionally correlated with the left IFG and to contribute to a phonologically based form of reading. The results as a whole demonstrate that lexical and sublexical processes in reading activate different regions within a complex network of brain structures.

Several functional neuroimaging studies have been carried out in healthy subjects to investigate the neural correlates of sadness. Importantly, there is little consistency among the results of these studies. Hypothesizing that individual differences may account for the discrepancies among these investigations, we conducted two functional magnetic resonance imaging (fMRI) studies to identify the neural circuitry underlying this basic emotion. In these two methodologically identical studies, two different groups (n = 10 for each study) of healthy female subjects were scanned while they were experiencing a transient state of sadness induced by viewing sad film excerpts. In the first of these studies, sadness was correlated with significant loci of activation in the anterior temporal pole and insula (P < 0.05, corrected). In the second study, however, sadness was correlated with significant activation in the orbitofrontal and medial prefrontal cortices (P < 0.05, corrected). In addition, individual statistical parametric maps revealed a marked degree of interindividual variability in both Study 1 and Study 2. These results strongly support the view that individual differences may be responsible for the inconsistencies found in the literature regarding the neural substrates of sadness and of other basic emotions. These findings also suggest that individual data should be reported in addition to group data, because they provide useful information about the variability present in the subjects investigated and, thus, about the typicality and generalizability of the results.

Background: The ability to voluntarily self-regulate negative emotion is essential to a healthy psyche. Indeed, a chronic incapacity to suppress negative emotion might be a key factor in the genesis of depression and anxiety. Regarding the neural underpinnings of emotional self-regulation, a recent functional neuroimaging study carried out by our group has revealed that the dorsolateral prefrontal cortex (DLPFC) and anterior cingulate cortex are involved in voluntary suppression of sexual arousal. As few things are known, still, with respect to the neural substrate underlying volitional self-regulation of basic emotions, here we used functional magnetic resonance imaging to identify the neural circuitry associated with the voluntary suppression of sadness., Methods: Twenty healthy female subjects were scanned during a Sad condition and a Suppression condition. In the Sad condition, subjects were instructed to react normally to sad film excerpts whereas, in the Suppression condition, they were asked to voluntarily suppress any emotional reaction in response to comparable stimuli., Results: Transient sadness was associated with significant loci of activation in the anterior temporal pole and the midbrain, bilaterally, as well as in the left amygdala, left insula, and right ventrolateral prefrontal cortex (VLPFC) (Brodmann area [BA] 47). Correlational analyses carried out between self-report ratings of sadness and regional blood oxygen level dependent (BOLD) signal changes revealed the existence of positive correlations in the right VLPFC (BA 47), bilaterally, as well as in the left insula and the affective division of the left anterior cingulate gyrus (BA 24/32). In the Suppression condition, significant loci of activation were noted in the right DLPFC (BA 9) and the right orbitofrontal cortex (OFC) (BA 11), and positive correlations were found between the self-report ratings of sadness and BOLD signal changes in the right OFC (BA 11) and right DLPFC (BA 9)., Conclusions: These results confirm the key role played by the DLPFC in emotional self-regulation. They also indicate that the right DLPFC and right OFC are components of a neural circuit implicated in voluntary suppression of sadness.

Questions pertaining to the neurobiological effects of psychotherapy are now considered among the most topical in psychiatry. With respect to this issue, positron emission tomography (PET) findings indicate that cognitive and behavioral modifications, occurring in a psychotherapeutic context, can lead to regional brain metabolic changes in patients with major depression or obsessive-compulsive disorder. The goal of the present functional magnetic resonance imaging (fMRI) study, which constitutes the first neuroimaging investigation of the effects of cognitive-behavioral therapy (CBT) using an emotional activation paradigm, was to probe the effects of CBT on the neural correlates of spider phobia. In order to do so, fMRI was used in subjects suffering from spider phobia (n = 12) to measure, before and after effective CBT, regional brain activity during the viewing of film excerpts depicting spiders. Normal control subjects were also scanned (once) while they were exposed to the same film excerpts. Results showed that, in phobic subjects before CBT, the transient state of fear triggered, during the viewing of the phobogenic stimuli, was correlated with significant activation of the right dorsolateral prefrontal cortex (Brodmann area-BA 10), the parahippocampal gyrus, and the visual associative cortical areas, bilaterally. For normal control subjects (n = 13), only the left middle occipital gyrus and the right inferior temporal gyrus were significantly activated. In phobic subjects before CBT, the activation of the dorsolateral prefrontal cortex (BA 10) may reflect the use of metacognitive strategies aimed at self-regulating the fear triggered by the spider film excerpts, whereas the parahippocampal activation might be related to an automatic reactivation of the contextual fear memory that led to the development of avoidance behavior and the maintenance of spider phobia. After successful completion of CBT, no significant activation was found in the dorsolateral prefrontal cortex (BA 10) or the parahippocampal gyrus. These findings suggest that a psychotherapeutic approach, such as CBT, has the potential to modify the dysfunctional neural circuitry associated with anxiety disorders. They further indicate that the changes made at the mind level, within a psychotherapeutic context, are able to functionally "rewire" the brain.