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The left inferior frontal gyrus and the bilateral ventral striatum are thought to be involved in motivation-mediated decision-making. Antipsychotics may influence this relationship, and atypical antipsychotics improve secondary negative symptoms in schizophrenia, such as loss of motivation, although the acute effects of pharmacological medication on motivation are not fully understood. In this single-blinded, randomized controlled trial, 49 healthy volunteers were randomized into three groups to receive a single dose of haloperidol, aripiprazole or placebo. Between 4.0 and 5.6 h later, participant’s brain blood-oxygen-level dependent (BOLD) activity was recorded using functional magnetic resonance imaging (fMRI) while completing a perceptual decision-making fMRI task consisting of one neutral and one motivated condition. Response bias, reflecting the participant’s willingness to say that the target stimulus is present, was calculated using signal detection theory. Concurrent with widespread changes in BOLD signal in the motivated vs. neutral condition, a less conservative, mathematically optimal response bias was observed in the motivated condition across the whole sample. Within-group differences in BOLD signal in the left inferior frontal gyrus and bilateral ventral striatum were observed between conditions in the aripiprazole and haloperidol groups, but not in the placebo group. No robust between-group differences in brain activity in the left inferior frontal gyrus or the bilateral ventral striatum were found. Overall, we found no robust evidence for an effect of either aripiprazole or haloperidol on motivationally mediated behavior. An interesting pattern of correlations possibly related to pharmacologically induced alterations in the dopamine system was observed, although findings remain inconclusive and must be replicated in larger samples.

Professional Pingju actors have been shown to exhibit practice-induced plastic changes in spontaneous regional brain activity; however, whether these changes are present in resting-state regional cerebral blood flow (CBF) remains largely unclear. Here, twenty professional Pingju opera actors and 20 age-, sex-, and handedness-matched untrained subjects were recruited, and resting-state CBF maps were obtained by using a three-dimensional pseudocontinuous arterial spin labelling sequence. Voxel-based comparisons of the CBF maps between the two groups were performed with two-sample t-tests, and correlation analyses between the CBF changes and years of training in the actor group were conducted. In addition, the CBF connectivity between regions with CBF alterations and the whole brain was computed and compared between the two groups. Compared with untrained subjects, the actors showed significantly higher CBF in the right inferior temporal gyrus, right middle temporal gyrus, left temporal pole, and left inferior frontal gyrus, whereas significantly lower CBF was not found in the actor group (voxel-level uncorrected p 0.001, cluster-level family-wise error corrected p 0.05). Furthermore, there was no correlation between the mean CBF values from significantly different clusters and the years of training, and no significant alterations in CBF connectivity were found in the actor group. Overall, these results provided preliminary evidence that neural plastic changes in CBF are present in professional Pingju opera actors, which may correspond to specific experiences associated with Pingju opera training.

Previous studies have identified the ventral and dorsal brain regions that respectively support semantic and non-semantic phonological access. Nevertheless, the specific role of the left occipitotemporal cortex (lOTC) in the two pathways of phonological access is ambiguous. To address that question, the present study compared word reading in Chinese (presumably relying on the semantic pathway) with that in English (presumably relying on the non-semantic pathway). Results revealed a clear dissociation in the involvement of the anterior and posterior lOTC in semantic and non-semantic phonological access. Specifically, the anterior lOTC showed greater activation for Chinese than for English, whereas the posterior lOTC showed greater activation for English than for Chinese. More importantly, both psychophysiological interaction analysis and resting-state functional connectivity analysis showed that the anterior lOTC was functionally connected to the ventral brain regions (e.g., left anterior fusiform gyrus, anterior temporal lobe, and ventral inferior frontal gyrus), whereas the posterior lOTC was functionally connected to the dorsal brain regions (e.g., left posterior superior temporal gyrus, supramarginal gyrus, and dorsal inferior frontal gyrus). These results suggest that the anterior and posterior lOTC are involved in semantic and non-semantic phonological access, respectively.

Being able to inhibit an impending movement in response to a contextual change is a distinctive feature of action control. Such inhibitory control relies on a complex cortical–subcortical network, including posterior prefrontal regions such as caudal inferior frontal gyrus and pre-supplementary motor area. According to hierarchical models of action control, both areas represent the intermediate level between prefronto-dependent and motor-related cortices. Going at a lower level, accumulating evidence speaks for an involvement of the primary motor cortex (M1) to dorsal premotor cortex (PMCd) or supplementary motor area proper (SMA-proper) pathways in producing inhibitory control. However, the clear-cut evidence for this conjecture is still missing. The aim of the present paper was to start filling this gap, investigating this lowest level of inhibitory control. We stimulated PMCd in a group of healthy volunteers with transcranial magnetic stimulation (TMS) or sham TMS during the response phase of a STOP-signal task performed with the lips. In a separate experimental group, we applied effective TMS/sham TMS to SMA-proper during the same task. We found that effective TMS over PMCd increased false-start errors in STOP trials (p = 0.0005), but had no effect on GO trial performance (p = 0.85). Effective TMS on SMA-proper produced no effect on STOP trials’ performance (p = 0.31) nor in the GO trial performance (p = 0.56). Our data show that there is at least a portion of PMCd playing a distinctive role in the control of mouth-related M1 during instructed visuomotor inhibitory behavior. This region could therefore represent a low-level hierarchical node for externally cued action inhibition.

The successful recovery from affective loss (i.e., bereavement, relationship breakup) has been linked to adult attachment style (AAS), a personality trait. Up to now, the association between AAS, affective loss experiences and brain gray matter volume is unclear. In 192 healthy subjects we investigated the association between MRI brain gray matter volume, applying voxel based morphometry, AAS (Relationship Scales Questionnaire (RSQ), subscales "avoidance" (AV) and "anxiety" (ANX)), and number of affective losses within the last 5 years (AL; List of Threatening Experiences Questionnaire). In a whole-brain analysis (p 0.05 FWE-corrected) ANX compared to AV was significantly more positively associated with brain gray matter volume in the left insula and in the pars opercularis of left inferior frontal gyrus. In additional region-of-interest (ROI) analyses (p 0.05 FWE-corrected), based on previously reported findings, no significant associations were observed. ANX and AV differently correlate with local volumes of the left insula and pars opercularis of the left inferior frontal gyrus, which are implicated in emotion processing, empathy and emotion regulation among other functions. Our results support the notion that individual attachment styles, which develop in the interplay of genes and social environment, differ in their correlation with brain structure.

Subtle semantic deficits can be observed in Alzheimer's disease (AD) patients even in the early stages of the illness. In this work, we tested the hypothesis that the semantic control network is deregulated in mild AD patients. We assessed the integrity of the semantic control system using resting-state functional magnetic resonance imaging in a cohort of patients with mild AD (n = 38; mean mini-mental state examination = 20.5) and in a group of age-matched healthy controls (n = 19). Voxel-wise analysis spatially constrained in the left fronto-temporal semantic control network identified two regions with altered functional connectivity (FC) in AD patients, specifically in the pars opercularis (POp, BA44) and in the posterior middle temporal gyrus (pMTG, BA21). Using whole-brain seed-based analysis, we demonstrated that these two regions have altered FC even beyond the semantic control network. In particular, the pMTG displayed a wide-distributed pattern of lower connectivity to several brain regions involved in language-semantic processing, along with a possibly compensatory higher connectivity to the Wernicke's area. We conclude that in mild AD brain regions belonging to the semantic control network are abnormally connected not only within the network, but also to other areas known to be critical for language processing.

To explore brain activity and the related neurochemical processes, current research focuses increasingly on the combined acquisition of 1 H MR spectra and fMRI data to investigate potential associations between local metabolite resting state levels and stimulus-induced BOLD signal changes. In this study, whole-brain fMRI measurements and localized functional 1 H MEGA-PRESS MRS scans were conducted at 3T in healthy subjects prior to and during acute pain stimulation to quantify resting state GABA+/tCr and Glx/tCr levels in the insular cortex together with their stimulus-induced changes and to explore associations between these neurochemical parameters with intra-regional but also inter-regional BOLD responses. Inter-regionally, a significant negative correlation between the BOLD signal of a cluster in the supplementary motor area with overlap to the mid-cingulate cortex (R = −0.56, p = 0.004) and the insular resting state GABA+/tCr was obtained. Furthermore, pain induced insular ΔGlx was significantly positively associated with the BOLD signal in the left superior frontal gyrus, left and right inferior frontal gyrus, left inferior parietal lobe, left superior temporal gyrus, left anterior insula and right posterior insula, with R values ranging from 0.59 to 0.73 (p

Individuals with mild cognitive impairment (MCI) are regarded as being at high risk of developing Alzheimer's disease (AD). The apolipoprotein E (APOE) e4 allele is a well-established genetic risk factor for developing AD. In the present study, by using voxel-mirrored homotopic connectivity (VMHC), we aimed to explore the potential functional disruptions in MCI APOE-e4 carriers. Resting-state functional magnetic resonance imaging was performed in 35 MCI APOE-e4 carriers (27 APOE-e3e4, 8 APOE-e4e4) and 42 MCI APOE-e4 noncarriers (APOE-e3e3). VMHC was employed to investigate the alterations in functional connectivity in MCI APOE-e4 carriers. We further investigated the seed-based functional connectivity between the VMHC values of altered regions and other brain regions in the two groups. The results showed that MCI APOE-e4 carriers presented increased VMHC in the inferior frontal gyrus/insula and middle frontal gyrus/superior frontal gyrus in comparison with noncarriers. We found that MCI APOE-e4 carriers showed increased functional connectivity between the seed regions (bilateral inferior frontal gyri/insula and bilateral middle frontal gyri/superior frontal gyri) and broad brain areas, including the frontal, temporal, parietal, and cerebellar regions. Our findings provide neuroimaging evidence for the modulation of the APOE genotype on the neurodegenerative disease phenotype and may be potentially important for monitoring disease progression in double-high-risk populations of AD.

In pragmatic language, there is an intentional distinction between the literal meaning of what is said, and what the speaker actually means. Previous neuroimaging investigations of pragmatic language have contrasted it with literal language; however, such contrasts may have been confounded by the higher levels of ambiguity in pragmatic language. Here, we used functional magnetic resonance imaging (fMRI) to compare pragmatic sentences (specifically requiring the interpretation of nonliteral meaning in the form of hints) with unintentionally ambiguous scenarios. Analysis showed that ambiguous language activated brain areas recognized to play a role in generating a theory of mind (ToM) that have previously been argued to support understanding of pragmatic language, specifically medial prefrontal cortex (mPFC), posterior cingulate cortex (PCC), and temporoparietal junction (TPJ). In contrast, the pragmatic scenarios drew on anterior temporal, superior parietal lobule, in addition to precuneus. While no effect of gender was found for unintentionally ambiguous stimuli, females showed greater activity than males within mPFC and inferior frontal gyrus (IFG) for pragmatic scenarios – regions thought to be involved in cognitive and affective empathy, respectively. Findings suggest that while areas underpinning ToM are sufficient to support meaning derivation in the context of ambiguity, reasoning about pragmatic intent is more reliant on access to self-referential memory.

This functional magnetic resonance imaging (fMRI) study investigated the brain regions underlying language task performance in adult second language (L2) learners. Specifically, we identified brain regions where the level of activation was associated with L2 fluency levels. Thirty Japanese-speaking adults participated in the study. All participants were L2 learners of English and had achieved varying levels of fluency, as determined by a standardized L2 English proficiency test, the Versant English Test (Pearson Education Inc., 2011). When participants performed the oral sentence building task from the production tasks administered, the dorsal part of the left inferior frontal gyrus (dIFG) showed activation patterns that differed depending on the L2 fluency levels: The more fluent the participants were, the more dIFG activation decreased. This decreased activation of the dIFG might reflect the increased automaticity of a syntactic building process. In contrast, when participants performed an oral story comprehension task, the left posterior superior temporal gyrus (pSTG) showed increased activation with higher fluency levels. This suggests that the learners with higher L2 fluency were actively engaged in post-syntactic integration processing supported by the left pSTG. These data imply that L2 fluency predicts neural resource allocation during language comprehension tasks as well as in production tasks. This study sheds light on the neural underpinnings of L2 learning by identifying the brain regions recruited during different language tasks across different modalities (production vs. comprehension).

Evidence from cognitive and social neuroscience research suggests that Theory of Mind (ToM), the ability to attribute mental states to others, is mediated by a group of brain regions collectively known as the ToM network. Nevertheless, there is significant variability in the functional activation of regions within this network across tasks. The goal of the present functional magnetic resonance imaging (fMRI) study was to examine the common and differential neural mechanisms of two aspects of ToM processing (emotion/mental-state recognition and intentional attribution) using three distinct, but complementary ToM tasks (Reading the Mind in the Eyes (RMIE), Reading the Mind in the Voice (RMIV), and Intentional Causal Attribution) in healthy adults. Participant accuracy was significantly worse in the ToM compared to the control condition across all tasks. Brain activation analyses replicated previously reported activation in inferior frontal gyrus (IFG) and middle temporal gyrus extending to posterior superior temporal sulcus (pSTS) in RMIE. Activation in the fusiform gyrus and bilateral middle temporal gyrus extending to temporo-parietal junction (TPJ) was unique to causality task. A region-of-interest analysis revealed shared activation in left IFG for RMIE and RMIV as well as TPJ recruitment specific to the causality task. The role of right TPJ in the causality task was further supported by a percent signal change analysis. A conjunction analysis revealed overlap in left IFG, left precentral gyrus, and left superior frontal gyrus activity across all tasks. These findings highlight common and differential recruitment of ToM regions according to task demand.

Humans have been consistently shown to be bad at making decisions, especially in disadvantageous situations. In this study, we designed a task that simulates real-life non-strategic gambling to examine the effect of win-lose balance situations (WIN, LOSS, TIE) on decision-making. In behavioral performances, participants showed shorter response time (RT) in LOSS than in WIN and TIE conditions. Imaging results revealed that decisions in WIN are associated with increased brain activations in the posterior cingulate cortex; decisions in LOSS are associated with increased brain activations in the insula and decreased activations in the inferior frontal gyrus (IFG). Positive correlation was found between brain activation in IFG and RT in LOSS. Overall, we concluded that, in disadvantageous conditions, participants are frustrated by their negative results and tend to make a random selection without full consideration. In advantageous conditions, participants' motivations to gamble are elicited and they tend to engage in more endeavors in making decisions.

In this study we were interested in the neural system supporting the audiovisual (AV) integration of emotional expression and emotional prosody. To this end normal participants were exposed to short videos of a computer-animated face voicing emotionally positive or negative words with the appropriate prosody. Facial expression of the face was either neutral or emotionally appropriate. To reveal the neural network involved in affective AV integration, standard univariate analysis of functional magnetic resonance (fMRI) data was followed by a random-effects Granger causality mapping (RFX-GCM). The regions that distinguished emotional from neutral facial expressions in the univariate analysis were taken as seed regions. In trials showing emotional expressions compared to neutral trials univariate analysis showed activation primarily in bilateral amygdala, fusiform gyrus, middle temporal gyrus/superior temporal sulcus and inferior occipital gyrus. When employing either the left amygdala or the right amygdala as a seed region in RFX-GCM we found connectivity with the right hemispheric fusiform gyrus, with the indication that the fusiform gyrus sends information to the Amygdala. These results led to a working model for face perception in general and for AV-affective integration in particular which is an elaborated adaptation of existing models.

Verbal insight problem solving means to break mental sets, to select the novel semantic information and to form novel, task-related associations. Although previous studies have identified the brain regions associated with these key processes, the interaction among these regions during insight is still unclear. In the present study, we explored the functional connectivity between the key regions during solving Chinese 'chengyu' riddles by using event-related functional magnetic resonance imaging. Results showed that both insight and noninsight solutions activated the bilateral inferior frontal gyri, middle temporal gyri and hippocampi, and these regions constituted a frontal to temporal to hippocampal neural pathway. Compared with noninsight solution, insight solution had a stronger functional connectivity between the inferior frontal gyrus and middle temporal gyrus in the right hemisphere. Our study reveals the neural pathway of information processing during verbal insight problem solving, and supports the right-hemisphere advantage theory of insight.

IntroductionNatural speech perception relies on both, auditory and visual information. Both sensory channels provide redundant and complementary information, such that speech perception is enhanced in healthy subjects, when both information channels are present.ObjectivesPatients with schizophrenia have been reported to have problems regarding this audiovisual integration process, but little is known about which neural processes are altered.AimsIn this study we investigated functional connectivity of Broca’s area in patients with schizophrenia.MethodsFunctional magnetic resonance imaging (fMRI) was performed in 15 schizophrenia patients and 15 healthy controls to study functional connectivity of Broca’s area during perception of videos of bisyllabic German nouns, in which audio and video either matched (congruent condition) or die not match (incongruent; e.g. video = hotel, audio = island).ResultsThere were differences in connectivity between experimental groups and between conditions. Broca’s area of the patient group showed connections to more brain areas than the control group. This difference was more prominent in the incongruent condition, for which only one connection between Broca's area and the supplementary motor area was found in control participants, whereas patients showed connections to 8 widely distributed brain areas.ConclusionsThe findings imply that audiovisual integration problems in schizophrenia result from maladaptive connectivity of Broca's area in particular when confronted with incongruent stimuli and are discussed in light of recent audio visual speech models.

Individuals have different levels of stress sensitivity. An individual’s predisposition to experience negative life events (NLEs) may make him/her more vulnerable to a series of psychopathological and physical diseases. However, the neuroanatomical correlates of individual differences in sensitivity to NLEs remain unknown. In this study, voxel-based morphometry was used to identify the gray matter (GM) associations of individual differences in sensitivity to NLEs measured by adolescent self-rating life events checklist. Results showed that there was a positive association between individual NLEs sensitivity and regional GM volume (rGMV) in the ventrolateral prefrontal cortex (VLPFC). GM was mostly evident in the left frontal operculum and a small part of the left middle frontal gyrus. This region was thought to play an important role in introception. Importantly, our study revealed that rumination served as a mediator between the rGMV of the VLPFC and individual NLEs sensitivity. These findings suggest that people with greater VLPFC might be more inclined to ruminate and the ruminative response style might make them more sensitive to NLEs.

Athletes exhibit better anticipation abilities than novices. However, it is not known whether this difference is related to different visual perceptions between them and which neural elements are involved in producing this difference. Fifteen elite basketball players and 15 novices participated in an action anticipation task with basketball free throw. Accurate rate for anticipation and gaze behavior were analyzed. Functional brain activity was recorded using functional magnetic resonance imaging. We found that the accurate rate for anticipation was higher in athletes than that in novices. Athletes showed more stable gaze fixation than novices and the locus of fixation was reliable in athletes but not in novices. Athletes showed higher activity in inferior parietal lobule and inferior frontal gyrus than novices during action anticipation. We conclude that the processes for action anticipation in elite athletes and novices are different and this difference is caused by different visual perceptions between them.

Functional magnetic resonance imaging (fMRI) has been widely used to identify altered intrinsic local neural activities and global networks of tinnitus patients. In this study, functional connectivity density (FCD) mapping, a newly developed voxelwise data-driven method based on fMRI, was applied for the first time to measure the functional reorganization pattern in thirty-two unilateral pulsatile tinnitus (PT) patients in the early stage of disease (less than 48 months). FCD analysis was employed to compute short-range and long-range FCD values. A correlation analysis with clinical variables was also performed. Compared with normal controls, PT patients showed significantly increased short-range FCD, mainly in the precuneus (PCu), bilateral inferior frontal gyrus (IFG) and middle occipital gyrus (MOG), and increased long-range FCD in the PCu, posterior cingulate cortex (PCC), and bilateral middle frontal gyrus (MFG). In addition, correlation analysis showed positive correlations between PT duration and short-range FCD values in the right MOG. Positive correlations were also found between the disease duration and the long-range FCD value in the PCC. The increased short-/long-range FCD in bilateral dorsal visual areas indicated that the enhanced pathway between the auditory cortex and bilateral dorsal visual areas may have activated the "auditory occipital activations" (AOAs) pathway. The bilaterally altered FCD values in the dorsal visual areas reflected the cooperation of different brain areas. This study is a foundation of the connectivity research in PT patients. Our work may advance the understanding of the disrupted neural network of patients with PT.

Creativity is the production of novel ideas that have value. Previous research indicated that while regions in the right hemisphere are implicated in the production of new ideas, damage to the left inferior frontal gyrus (IFG) is associated with increased creativity, indicating that the left IFG damage may have a "releasing" effect on creativity. To examine this, in the present study we used transcranial direct current stimulation (tDCS) to modulate activity of the right and the left IFG. In the first experiment we show that whereas anodal tDCS over the right IFG coupled with cathodal tDCS over the left IFG increases creativity as measured by a verbal divergent thinking task, the reverse stimulation does not affect creative production. To further confirm that only altering the balance between the two hemispheres is crucial in modulating creativity, in the second experiment we show that stimulation targeting separately the left IFG (cathodal stimulation) or the right IFG (anodal stimulation) did not result in changes in creativity as measured by verbal divergent thinking. These findings support the balance hypothesis, according to which verbal creativity requires a balance of activation between the right and the left frontal lobes, and more specifically, between the right and the left IFG.

Although extensively investigated in socio-cognitive neuroscience, empathy is difficult to study. The first difficulty originates in its multifaceted nature. According to the multidimensional model, empathy combines emotional, automatic (simulation), cognitive (mentalizing) and regulatory (executive functions) processes. Substantial functional magnetic resonance imaging (fMRI) data demonstrated that co-activations in the mirror neuron system (MNS) and mentalizing network (MENT) sustain this co-recruitment of so-called first- and second-person-like processes. Because of the poor temporal resolution of fMRI techniques, we currently lack evidence about the precise timing of the MNS-MENT combination. An important challenge is, thus, to disentangle how MNS and MENT dynamically work together along time in empathy. Moreover, the role of the executive functions in the MNS-MENT combination time course is still unknown. Second, empathy - feeling into - is closely related to sympathy - feeling with - and both phenomena are often conflated in experimental studies on intersubjectivity. In this electrical neuroimaging (EEG) pilot-study, we tested whether the egocentered vs. heterocentered visuo-spatial mechanisms respectively associated with sympathy and empathy differentially modulate the dynamic combination of the MNS-MENT activations in their respective neural time course. For that, we employed our newly developed behavioral paradigm assessing the visuo-spatial - but not emotional - features of empathy and sympathy. Using a data-driven approach, we report that empathy and sympathy are underlied by sequential activations in the MNS from the insula to the inferior frontal gyrus (IFG) between 63ms and 424ms. However, at 333-424ms, empathy triggered greater co-activations in the right IFG and dorsolateral prefrontal cortex (dlPFC) (executive functions). Linking together our present and prior (Thirioux et al., 2010) findings from the same dataset, we suggest that this greater recruitment of the right dlPFC monitors the shift from egocentered and first-person-like mechanisms in the MNS to heterocentered and second-person-like mechanisms in the left temporo-parietal junction within the MENT, i.e., reflecting the onset of perspective-change processes in the neural time course of empathy. Contrasting with sympathy, this recruitment of the executive functions could modulate the output end of the mirroring processing in the premotor and sensorimotor cortices.

The left occipitotemporal cortex has been found sensitive to the hierarchy of increasingly complex features in visually presented words, from individual letters to bigrams and morphemes. However, whether this sensitivity is a stable property of the brain regions engaged by word recognition is still unclear. To address the issue, the current study investigated whether different task demands modify this sensitivity. Participants viewed real English words and stimuli with hierarchical word-likeness while performing a lexical decision task (i.e., to decide whether each presented stimulus is a real word) and a symbol detection task. General linear model and independent component analysis indicated strong activation in the fronto-parietal and temporal regions during the two tasks. Furthermore, the bilateral inferior frontal gyrus and insula showed significant interaction effects between task demand and stimulus type in the pseudoword condition. The occipitotemporal cortex showed strong main effects for task demand and stimulus type, but no sensitivity to the hierarchical word-likeness was found. These results suggest that different task demands on semantic, phonological and orthographic processes can influence the involvement of the relevant regions during visual word recognition.

Anorexia nervosa is a severe illness and shows one of the highest death rates among psychiatric or psychosomatic diseases. However, despite several lines of research, the etiology of this disease is still unknown. One of those features is the rigidity of behaviors, for example, controlling of weight and pursuing of thinness, that often meets the criteria for obsessive-compulsive behavior. In this study, it was investigated whether the clinical feature of compulsivity in anorexia nervosa patients relates to regional brain activation. Using functional magnetic resonance imaging, 12 severely anorectic women were compared to 12 normal-weight female individuals following a cue-reactivity paradigm. Cues comprised food cues of high and low calorie content as well as eating-related utensils. Voxel-based morphometric analysis indicated significantly overall reduced gray matter volume and significantly increased cerebrospinal fluids in anorexia nervosa (AN) patients, which was controlled for in subsequent analyses. Following the high-calorie stimulation, AN patients activated the right caudate body and right precuneus, whereas control subjects did not show significant regional activations. In both other conditions, low-calorie foods and eating utensils, regional brain activations did not survive FDR thresholds. During the high-calorie condition, compulsivity, that is, the subscore "obsessive thoughts," predicted activation of the superior frontal gyrus [Brodmann areas (BA) 10], inferior frontal gyrus, anterior cingulate cortex (BA 32), cingulate gyrus (BA 24), caudate body, cuneus, pre- and postcentral gyrus. The subscore "compulsive acts" correlated with activation of the claustrum during the high-calorie condition and predicted a number of deactivations of frontal and temporal regions. We conclude that in severely anorectic individuals, the degree of compulsivity predicts activation and deactivation of the fronto-striatal pathway.

Olfactory disorders are common in patients with idiopathic Parkinson's disease (IPD). In IPD patients with hyposmia olfactory event-related potentials (ERPs) are typically found to be delayed or absent. Altered ERPs in IPD patients may also be consistent with reduced neuronal activity in the medial temporal lobe following olfactory stimulation, as demonstrated by functional magnetic resonance imaging (fMRI). We analyzed ERPs and fMRI scans of hyposmic IPD patients (n=18) to gain further insight about the brain regions involved in generation of olfactory ERPs. Patients were separated into two groups (n=9 per group), based on the detectability (+) or non-detectability (-) of ERPs. Central activation during olfactory stimulation was examined using fMRI. Both ERP+ and ERP- patients showed activity in brain areas relevant to olfactory processing, such as the amygdala, parahippocampal regions, and temporal regions (BA 37, 21/22). Comparison of both groups revealed higher activation in ERP+ patients, especially in the amygdala, parahippocampal cortex, inferior frontal gyrus (BA 47), insula, cingulate gyrus, striatum, and inferior temporal gyrus. The relationship between the expression of olfactory ERPs and cortical activation patterns seen during olfactory stimulation in fMRI in IPD patients supports the idea that ERPs are a sensitive marker of neurodegeneration in olfactory regions. In accordance with current neuropathological staging concepts, olfactory ERPs may be reflecting pathological changes in olfactory regions, independent of the typically observed nigro-striatal degeneration in IPD. Reduced activation of primary olfactory areas in the ERP-group may reflect a severe disruption of olfactory processing in these patients.