Brain functional changes in facial expression recognition in patients with major depressive disorder before and after antidepressant treatment A functional magnetic resonance imaging study

Functional magnetic resonance imaging was used during emotion recognition to identify changes in functional brain activation in 21 first-episode, treatment-naive major depressive disorder patients before and after antidepressant treatment. Following escitalopram oxalate treatment, patients exhibited decreased activation in bilateral precentral gyrus, bilateral middle frontal gyrus, left middle temporal gyrus, bilateral postcentral gyrus, left cingulate and right parahippocampal gyrus, and increased activation in right superior frontal gyrus, bilateral superior parietal lobule and left occipital gyrus during sad facial expression recognition. After antidepressant treatment, patients also exhibited decreased activation in the bilateral middle frontal gyrus, bilateral cingulate and right parahippocampal gyrus, and increased activation in the right inferior frontal gyrus, left fusiform gyrus and right precuneus during happy facial expression recognition. Our experimental findings indicate that the limbic-cortical network might be a key target region for antidepressant treatment in major depressive disorder.     

Brain glucose metabolism difference between bipolar and unipolar mood disorders in depressed and euthymic states

Background

Functional brain imaging studies have consistently demonstrated abnormalities in regional cerebral glucose metabolism in the prefrontal cortex in patients with mood disorders (MD). These studies, however, have not clarified the differential characteristics of glucose metabolism between depressed and euthymic states, or between bipolar mood disorder (BP) and unipolar mood disorder (UP).

Methods

We used [¹⁸F]fluorodeoxyglucose (FDG) positron emission tomography (PET) to evaluate the differences in glucose metabolism at resting state. We compared 30 depressed and 17 euthymic female patients with mood disorders with age-, IQ-, and socioeconomically matched 20 healthy controls (HCs). Then, BP and UP patients were separately analyzed. The PET data were objectively analyzed by statistical parametric mapping (SPM).

Results

Compared with HCs, the depressed MD patients showed significantly lower glucose metabolism in the bilateral frontal gyri, left cingulate gyrus, bilateral temporal gyri, right insula, bilateral inferior parietal lobules, and right occipital gyrus. In contrast, the euthymic MD patients demonstrated fewer areas with significant reduction. When the depressed BP patients were separately compared with HCs, the glucose metabolism was found to be significantly lower in the bilateral frontal gyri, right cingulate gyrus, and bilateral inferior parietal lobules. Meanwhile, the depressed UP patients showed a significantly lower metabolism in the bilateral frontal gyri, left cingulate gyrus, bilateral temporal gyri, bilateral insulae, bilateral inferior parietal lobules, and right occipital gyrus.

Conclusions

The results of this study provide evidence of persistent hypometabolism in depressed MD patients, particularly in the frontal gyrus. Although the conclusions are limited in the cross-sectional study, these findings suggest that abnormalities in the right frontal gyrus, left temporal gyrus, and left cingulate gyrus tend to normalize as the depression symptoms improve, although those in the left frontal gyrus, right cingulate gyrus, and right temporal gyrus persist. This study also elucidated the cerebral hypofunction specific to each BP and UP. BP patients showed a decrease in glucose metabolism in the right anterior cingulate and UP patients did in the right temporal gyrus, right insula, and left posterior cingulate. This study clarified the differences between subtypes.     

Semantic association investigated with functional MRI and independent component analysis

Semantic association, an essential element of human language, enables discourse and inference. Neuroimaging studies have revealed localization and lateralization of semantic circuitry, making substantial contributions to cognitive neuroscience. However, because of methodological limitations, these investigations have only identified individual functional components rather than capturing the behavior of the entire network. To overcome these limitations, we have implemented group independent component analysis (ICA) to investigate the cognitive modules used by healthy adults performing the fMRI semantic decision task. When compared with the results of a standard general linear modeling (GLM) analysis, ICA detected several additional brain regions subserving semantic decision. Eight task-related group ICA maps were identified, including left inferior frontal gyrus (BA44/45), middle posterior temporal gyrus (BA39/22), angular gyrus/inferior parietal lobule (BA39/40), posterior cingulate (BA30), bilateral lingual gyrus (BA18/23), inferior frontal gyrus (L>R, BA47), hippocampus with parahippocampal gyrus (L>R, BA35/36), and anterior cingulate (BA32/24). Although most of the components were represented bilaterally, we found a single, highly left-lateralized component that included the inferior frontal gyrus and the medial and superior temporal gyri, the angular and supramarginal gyri, and the inferior parietal cortex. The presence of these spatially independent ICA components implies functional connectivity and can be equated with their modularity. These results are analyzed and presented in the framework of a biologically plausible theoretical model in preparation for similar analyses in patients with right- or left-hemispheric epilepsies.     

Neuroscience of learning arithmetic—Evidence from brain imaging studies

It is widely accepted that the human brain is remarkably adaptive not only in child development, but also during adulthood. Aim of this work is to offer an overview and a systematic analysis of neuroimaging studies on the acquisition of arithmetic expertise. In normally developing children and adults, the gain of arithmetic competence is reflected by a shift of activation from frontal brain areas to parietal areas relevant for arithmetic processing. A shift of activation is also observed within the parietal lobe from the intraparietal sulci to the left angular gyrus. Increases in angular gyrus activation with gaining of expertise have also been documented in other cognitive domains. It appears that the left angular gyrus activation is modulated by inter-individual differences in arithmetic performance. The comparison of normal individuals with exceptionally performing individuals (e.g., calculating prodigies) suggests that the experts’ arithmetic proficiency relies on a more extended activation network than the network found in non-experts. In expert individuals with long-lasting, extensive mathematical training, specific structural brain modifications are also evident.     

偏头痛与静息态脑功能连接研究

目的本文研究采用静息态功能磁共振成像(rfMRI)技术描述偏头痛患者静息态脑功能连接改变,为探索偏头痛的发病机制提供影像学资料。方法收集16例偏头痛患者与16例健康对照,采集rfMRI成像,计算低频振幅,找出感兴趣区做功能连接进行统计分析。结果偏头痛患者左侧岛叶、左侧额下回低频振幅显著低于对照组,右侧视觉皮质低频振幅显著高于对照组;以左侧额下回、右侧枕中回为感兴趣区,发现左侧额下回与脑干之间的功能连接增强,与双侧枕叶之间的功能连接减弱;右侧枕中回与双侧楔前叶延伸至扣带回中部区域之间的功能连接增强,与双侧中央前回、双侧缘上回、双侧颞上回及双侧额下回之间的功能连接减弱。结论偏头痛患者无头痛发作时神经元活动强度改变,大脑功能连接异常,这导致大脑整合信息过程改变,并与偏头痛发病相关。     

A network approach to response inhibition: dissociating functional connectivity of neural components involved in action restraint and action cancellation

The ability to inhibit action tendencies is vital for adaptive human behaviour. Various paradigms are supposed to assess action inhibition and are often used interchangeably. However, these paradigms are based on different conceptualizations (action restraint vs. action cancellation) and the question arises as to what extent different conceptualizations of inhibitory processing are mirrored in a distinct neural activation pattern. We used functional magnetic resonance imaging to investigate the neural correlates of action restraint vs. action cancellation. Analyses of local activity changes as well as network connectivity measures revealed a strong overlap of activation within a common action inhibition network including inferior frontal, pre‐supplementary motor and thalamic brain areas as well as the anterior cingulate cortex. Furthermore, our findings pointed to additional neural networks that are distinct for action restraint (i.e. right superior frontal gyrus, left middle frontal gyrus, and bilateral anterior cingulate cortex) and action cancellation (i.e. right middle frontal gyrus, posterior cingulate cortex, and parietal regions). Our connectivity analyses showed that different inhibitory modalities largely relied on a task‐independent global inhibition network within the brain. Furthermore, they suggested that the conceptually distinct inhibitory aspects of action restraint vs. action cancellation also activated additional specific brain regions in a task‐dependent manner. This has implications for the choice of tasks in an empirical setting, but is also relevant for various clinical contexts in which inhibition deficits are considered a diagnostic feature.     

Differentiating between self and others: an ALE meta-analysis of fMRI studies of self-recognition and theory of mind

The perception of self and others is a key aspect of social cognition. In order to investigate the neurobiological basis of this distinction we reviewed two classes of task that study self-awareness and awareness of others (theory of mind, ToM). A reliable task to measure self-awareness is the recognition of one’s own face in contrast to the recognition of others’ faces. False-belief tasks are widely used to identify neural correlates of ToM as a measure of awareness of others. We performed an activation likelihood estimation meta-analysis, using the fMRI literature on self-face recognition and false-belief tasks. The brain areas involved in performing false-belief tasks were the medial prefrontal cortex (MPFC), bilateral temporo-parietal junction, precuneus, and the bilateral middle temporal gyrus. Distinct self-face recognition regions were the right superior temporal gyrus, the right parahippocampal gyrus, the right inferior frontal gyrus/anterior cingulate cortex, and the left inferior parietal lobe. Overlapping brain areas were the superior temporal gyrus, and the more ventral parts of the MPFC. We confirmed that self-recognition in contrast to recognition of others’ faces, and awareness of others involves a network that consists of separate, distinct neural pathways, but also includes overlapping regions of higher order prefrontal cortex where these processes may be combined. Insights derived from the neurobiology of disorders such as autism and schizophrenia are consistent with this notion.     

Age-related changes in right middle frontal gyrus volume correlate with altered episodic retrieval activity

Age-related deficits in episodic retrieval have been associated with volume reductions in the middle frontal gyrus (MFG). However, it remains unclear how this age-related reduction in MFG volume correlates with neural activity during retrieval. To address this, we conducted in vivo volumetry of the frontal cortex in young and older human adults and found more volume loss on the right than on the left MFG with age. We then examined how left and right MFG volume correlated with fMRI activity during successful retrieval of item, spatial context, and temporal context information in both age groups. In young adults, larger right MFG volume was positively correlated with greater activity in a commonly found episodic retrieval network that included bilateral dorsolateral prefrontal cortex (DLPFC) and bilateral inferior parietal cortex. Within this network, left DLPFC and right inferior parietal cortex activity predicted memory performance. In older adults, a positive structure-function association in DLPFC for either left or right MFG/DLPFC was not observed. Instead, right MFG volume was negatively correlated with activity in several regions in older adults, including the parahippocampal cortex (PHC) and anterior cingulate. Less activity in the PHC region predicted better item memory, and less activity in the anterior cingulate predicted better spatial context accuracy in older adults. We conclude that age-related change in the structure-function association in MFG/DLPFC impacts retrieval activity and performance, and those older adults with larger right MFG volume attempt to compensate for this change by modifying activity in other brain regions to help retrieval performance.     

The neural correlates of retrieval and procedural strategies in mental arithmetic: A functional neuroimaging meta-analysis

Mental arithmetic is a complex skill of great importance for later academic and life success. Many neuroimaging studies and several meta-analyses have aimed to identify the neural correlates of mental arithmetic. Previous meta-analyses of arithmetic grouped all problem types into a single meta-analytic map, despite evidence suggesting that different types of arithmetic problems are solved using different strategies. We used activation likelihood estimation (ALE) to conduct quantitative meta-analyses of mental arithmetic neuroimaging (n = 31) studies, and subsequently grouped contrasts from the 31 studies into problems that are typically solved using retrieval strategies (retrieval problems) (n = 18) and problems that are typically solved using procedural strategies (procedural problems) (n = 19). Foci were compiled to generate probabilistic maps of activation for mental arithmetic (i.e., all problem types), retrieval problems, and procedural problems. Conjunction and contrast analyses were conducted to examine overlapping and distinct activation for retrieval and procedural problems. The conjunction analysis revealed overlapping activation for retrieval and procedural problems in the bilateral inferior parietal lobules, regions typically associated with magnitude processing. Contrast analyses revealed specific activation in the left angular gyrus for retrieval problems and specific activation in the inferior frontal gyrus and cingulate gyrus for procedural problems. These findings indicate that the neural bases of arithmetic systematically differs according to problem type, providing new insights into the dynamic and task-dependent neural underpinnings of the calculating brain.     

Cortical networks for working memory and executive functions sustain the conscious resting state in man

The cortical anatomy of the conscious resting state (REST) was investigated using a meta-analysis of nine positron emission tomography (PET) activation protocols that dealt with different cognitive tasks but shared REST as a common control state. During REST, subjects were in darkness and silence, and were instructed to relax, refrain from moving, and avoid systematic thoughts. Each protocol contrasted REST to a different cognitive task consisting either of language, mental imagery, mental calculation, reasoning, finger movement, or spatial working memory, using either auditory, visual or no stimulus delivery, and requiring either vocal, motor or no output. A total of 63 subjects and 370 spatially normalized PET scans were entered in the meta-analysis. Conjunction analysis revealed a network of brain areas jointly activated during conscious REST as compared to the nine cognitive tasks, including the bilateral angular gyrus, the left anterior precuneus and posterior cingulate cortex, the left medial frontal and anterior cingulate cortex, the left superior and medial frontal sulcus, and the left inferior frontal cortex. These results suggest that brain activity during conscious REST is sustained by a large scale network of heteromodal associative parietal and frontal cortical areas, that can be further hierarchically organized in an episodic working memory parieto-frontal network, driven in part by emotions, working under the supervision of an executive left prefrontal network.     

难治性癫痫患者楔前叶功能连接的静息态功能磁共振成像研究

目的应用静息态功能磁共振成像(rs-f MRI)探讨难治性癫痫患者楔前叶与全脑功能连接的改变及其意义。方法对23例难治性癫痫患者(癫痫组)及23名健康人(对照组)进行rs-f MRI检查,采集数据后采用功能连接的方法,分别计算以左侧楔前叶和右侧楔前叶为感兴趣区与全脑的功能连接,运用双样本t检验的统计学方法发现两组的显著性差异并进行分析。结果癫痫组左侧楔前叶与双侧顶下小叶、双侧岛叶、右侧缘上回、右侧额中回和双侧额下回的功能连接较对照组减弱(均P0.05);癫痫组左侧楔前叶与双侧海马旁回、双侧额上回、左侧后扣带回的功能连接较对照组增强(均P0.05)。癫痫组右侧楔前叶与左侧顶下小叶、右侧缘上回、右侧额中回、右侧额下回的功能连接较对照组减弱(均P0.05);癫痫组右侧楔前叶与双侧楔叶、左侧后扣带回的功能连接较对照组增强(均P0.05)。结论难治性癫痫患者静息状态下楔前叶与全脑的功能连接存在异常,"默认网络"功能的抑制可能是癫痫患者意识及认知等功能损害的重要原因。     

Morphometric Brain Abnormalities in Schizophrenia in a Population-Based Sample: Relationship to Duration of Illness

Biased recruitment and sample selection may cause variability in neuroimaging studies. Epidemiologically principled population-based magnetic resonance imaging (MRI) studies of schizophrenia are very rare. We gathered structural MRI data on 154 subjects from the Northern Finland 1966 Birth Cohort, aged 33–35 (100 controls, 54 schizophrenia patients). Regional differences in density of gray matter, white matter, and cerebrospinal fluid (CSF) were identified between groups using nonparametric statistical analysis, and the relationship of the regional differences to duration of illness was explored. Gray matter reductions were found bilaterally in the cerebellum, thalamus, basal ganglia, middle frontal gyrus, inferior frontal gyrus, precentral gyrus, insula, superior temporal gyrus, fusiform gyrus, parahippocampal gyrus, cuneus, and lingual gyrus; in the left posterior cingulate, superior frontal gyrus, transverse temporal gyrus, and precuneus; and in the right postcentral gyrus. Gray matter excesses were observed bilaterally in the basal ganglia, anterior cingulate, and medial orbitofrontal cortices. There were white matter deficits in an extensive network including inter- and intrahemispheric tracts bilaterally in the frontal, temporal, parietal, and occipital lobes, subcortical structures, cerebellum, and brain stem. CSF excesses were found bilaterally in the lateral ventricles, third ventricle, interhemispheric, and left Sylvian fissure. We replicated the previous findings of structural brain abnormalities in schizophrenia on a general population level. Gray and white matter deficits were associated with duration of illness suggesting either that developmental brain deficits relate to an earlier age of onset or that brain abnormalities in schizophrenia are progressive in nature.     

Relationships between years of education,regional grey matter volumes,and working memory-related brain activity in healthy older adults

The aim of this study was to examine the relationships between educational attainment, regional grey matter volume, and functional working memory-related brain activation in older adults. The final sample included 32 healthy older adults with 8 to 22 years of education. Structural magnetic resonance imaging (MRI) was used to measure regional volume and functional MRI was used to measure activation associated with performing an n-back task. A positive correlation was found between years of education and cortical grey matter volume in the right medial and middle frontal gyri, in the middle and posterior cingulate gyri, and in the right inferior parietal lobule. The education by age interaction was significant for cortical grey matter volume in the left middle frontal gyrus and in the right medial cingulate gyrus. In this region, the volume loss related to age was larger in the low than high-education group. The education by age interaction was also significant for task-related activity in the left superior, middle and medial frontal gyri due to the fact that activation increased with age in those with higher education. No correlation was found between regions that are structurally related with education and those that are functionally related with education and age. The data suggest a protective effect of education on cortical volume. Furthermore, the brain regions involved in the working memory network are getting more activated with age in those with higher educational attainment.     

DTI and impulsivity in schizophrenia: a first voxelwise correlational analysis

Compromised white matter (WM) integrity in inferior frontal WM has been related to impulsivity in men with schizophrenia. However, these relationships may be more widespread. Fractional anisotropy (FA) derived from diffusion tensor imaging of 25 men with schizophrenia was transformed into Talairach space. Correlations between FA and impulsiveness were examined on a voxelwise basis. We found negative correlations between FA and impulsivity in inferior frontal WM, anterior cingulate, caudate, insula, and inferior parietal lobule. Positive correlations were obtained in the left postcentral gyrus, right superior/middle temporal gyrus, and bilateral fusiform gyrus. These areas may comprise a fronto-temporo-limbic circuit that modulates impulsivity. The voxelwise correlation method can serve as a hypothesis-generation method for relating target behaviors to their underlying neural networks.     

~(18)F-FDG PET显像观察特发性快眼动睡眠期行为障碍患者脑葡萄糖代谢特点的研究

目的探讨~(18)F-FDG PET显像观察特发性快眼动睡眠期行为障碍(iRBD)患者脑葡萄糖代谢改变和iRBD脑葡萄糖代谢改变与病程间的相关性。方法纳入多导睡眠监测(PSG)确诊的iRBD患者20例(iRBD组)和年龄、性别匹配的健康对照者19例(对照组)。两组均行~(18)F-FDG PET脑显像。基于自动解剖标记模板将大脑划分为90个左右对称的脑区,计算各脑区葡萄糖代谢半定量值。对iRBD组和对照组各脑区葡萄糖代谢半定量值进行独立样本t检验;并对iRBD组脑葡萄糖代谢改变与病程行Pearson相关分析。结果 (1)与对照组比较,iRBD组的双侧背外侧额上回、双侧眶部额上回、双侧眶部额中回、双侧海马、双侧海马旁回、双侧杏仁核、左侧眶部额下回、左侧岛叶、左侧内侧与旁扣带脑回、左侧中央旁小叶、左侧苍白球的葡萄糖代谢半定量值均增高(P0.05);双侧距状裂周围皮质、双侧楔叶、双侧舌回、双侧枕上回、双侧枕中回、双侧枕下回、双侧角回、双侧颞上回、双侧颞中回、右侧颞横回的葡萄糖代谢半定量值均降低(P0.05)。Pearson相关分析结果,iRBD组双侧杏仁核、双侧颞上回、右侧楔叶、右侧枕上回、右侧颞横回、左侧海马、左侧颞中回的葡萄糖代谢半定量值与病程呈正相关(P0.05);而双侧眶部额上回、双侧眶部额中回、左侧中央旁小叶、左侧眶部额下回、左侧内侧和旁扣带回、右侧背外侧额上回、右侧海马旁回的葡萄糖代谢半定量值与病程呈负相关(P0.05)。结论 iRBD患者脑内存在疾病相关的葡萄糖代谢水平改变,有助于客观评估iRBD病情的变化。     

Specialization of phonological and semantic processing in Chinese word reading

The purpose of this study was to examine the neurocognitive network for processing visual word forms in native Chinese speakers using functional magnetic resonance imaging (fMRI). In order to compare the processing of phonological and semantic representations, we developed parallel rhyming and meaning association judgment tasks that required explicit access and manipulation of these representations. Subjects showed activation in left inferior/middle frontal gyri, bilateral medial frontal gyri, bilateral middle occipital/fusiform gyri, and bilateral cerebella for both the rhyming and meaning tasks. A direct comparison of the tasks revealed that the rhyming task showed more activation in the posterior dorsal region of the inferior/middle frontal gyrus (BA 9/44) and in the inferior parietal lobule (BA 40). The meaning task showed more activation in the anterior ventral region of the inferior/middle frontal gyrus (BA 47) and in the superior/middle temporal gyrus (BA 22,21). These findings are consistent with previous studies in English that suggest specialization of inferior frontal regions for the access and manipulation of phonological vs. semantic representations, but also suggest that this specialization extends to the middle frontal gyrus for Chinese. These findings are also consistent with the suggestion that the left middle temporal gyrus is involved in representing semantic information and the left inferior parietal lobule is involved in mapping between orthographic and phonological representations.     

Learning complex arithmetic--an fMRI study

Aim of the present functional magnet resonance imaging (fMRI) study was to detect modifications of cerebral activation patterns related to learning arithmetic. Thirteen right-handed subjects were extensively trained on a set of 18 complex multiplication problems. In the following fMRI session, trained and untrained problems (closely matched for difficulty) were presented in blocked order alternating with a number matching task and a fact retrieval task. Importantly, left hemispheric activations were dominant in the two contrasts between untrained and trained condition, suggesting that learning processes in arithmetic are predominantly supported by the left hemisphere. Contrasting untrained versus trained condition, the left intraparietal sulcus showed significant activations, as well as the inferior parietal lobule. A further significant activation was found in the left inferior frontal gyrus. This activation may be accounted for by higher working memory demands in the untrained as compared to the trained condition. Contrasting trained versus untrained condition a significant focus of activation was found in the left angular gyrus. Following the triple-code model [Science 284 (1999) 970], the shift of activation within the parietal lobe from the intraparietal sulcus to the left angular gyrus suggests a modification from quantity-based processing to more automatic retrieval. The present study shows that the left angular gyrus is not only involved in arithmetic tasks requiring simple fact retrieval, but may show significant activations as a result of relatively short training of complex calculation.     

Neural substrates for functionally discriminating self-face from personally familiar faces

Understanding the neurobiological substrates of self-recognition yields important insight into socially and clinically critical cognitive functions such as theory of mind. Experimental evidence suggests that right frontal and parietal lobes preferentially process self-referent information. Recognition of one's own face is an important parameter of self-recognition, but well-controlled experimental data on the brain substrates of self-face recognition is limited. The goal of this study was to characterize the activation specific to self-face in comparison with control conditions of two levels of familiarity: unknown unfamiliar face and the more stringent control of a personally familiar face. We studied 12 healthy volunteers who made "unknown," "familiar," and "self" judgments about photographs of three types of faces: six different novel faces, a personally familiar face (participant's fraternity brother), and their own face during an event-related functional MRI (fMRI) experiment. Contrasting unknown faces with baseline showed activation of the inferior occipital lobe, which supports previous findings suggesting the presence of a generalized face-processing area within the inferior occipital-temporal region. Activation in response to a familiar face, when contrasted with an unknown face, invoked insula, middle temporal, inferior parietal, and medial frontal lobe activation, which is consistent with an existing hypothesis suggesting familiar face recognition taps neural substrates that are different from those involved in general facial processing. Brain response to self-face, when contrasted with familiar face, revealed activation in the right superior frontal gyrus, medial frontal and inferior parietal lobes, and left middle temporal gyrus. The contrast familiar vs. self produced activation only in the anterior cingulate gyrus. Our results support the existence of a bilateral network for both perceptual and executive aspects of self-face processing that cannot be accounted for by a simple hemispheric dominance model. This network is similar to those implicated in social cognition, mirror neuron matching, and face-name matching. Our findings also show that some regions of the medial frontal and parietal lobes are specifically activated by familiar faces but not unknown or self-faces, indicating that these regions may serve as markers of face familiarity and that the differences between activation associated with self-face recognition and familiar face recognition are subtle and appear to be localized to lateral frontal, parietal, and temporal regions.     

Using fMRI to dissociate sensory encoding from cognitive evaluation of heat pain intensity

Neuroimaging studies of painful stimuli in humans have identified a network of brain regions that is more extensive than identified previously in electrophysiological and anatomical studies of nociceptive pathways. This extensive network has been described as a pain matrix of brain regions that mediate the many interrelated aspects of conscious processing of nociceptive input such as perception, evaluation, affective response, and emotional memory. We used functional magnetic resonance imaging in healthy human subjects to distinguish brain regions required for pain sensory encoding from those required for cognitive evaluation of pain intensity. The results suggest that conscious cognitive evaluation of pain intensity in the absence of any sensory stimulation activates a network that includes bilateral anterior insular cortex/frontal operculum, dorsal lateral prefrontal cortex, bilateral medial prefrontal cortex/anterior cingulate cortex, right superior parietal cortex, inferior parietal lobule, orbital prefrontal cortex, and left occipital cortex. Increased activity common to both encoding and evaluation was observed in bilateral anterior insula/frontal operculum and medial prefrontal cortex/anterior cingulate cortex. We hypothesize that these two regions play a crucial role in bridging the encoding of pain sensation and the cognitive processing of sensory input.