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Background: the safety of anaesthesia has improved as a result of better control of anaesthetic depth. However, conventional monitoring does not inform on the nature of nociceptive processes during unconsciousness. A means of inferring the quality of potentially painful experiences could derive from analysis of brain activity using neuroimaging. We have evaluated the dose effects of remifentanil on brain response to noxious stimuli during deep sedation and spontaneous breathing. Methods: optimal data were obtained in 26 healthy subjects. Pressure stimulation that proved to be moderately painful before the experiment was applied to the thumbnail. Functional MRI was acquired in 4-min periods at low (0.5 ng ml-1), medium (1 ng ml-1), and high (1.5 ng ml-1) target plasma concentrations of remifentanil at a stable background infusion of propofol adjusted to induce a state of light unconsciousness. Results: at low remifentanil doses, we observed partial activation in brain areas processing sensory-discriminative and emotional-affective aspects of pain. At medium doses, relevant changes were identified in structures highly sensitive to general brain arousal, including the brainstem, cerebellum, thalamus, auditory and visual cortices, and the frontal lobe. At high doses, no significant activation was observed. Conclusions: the response to moderately intense focal pressure in pain-related brain networks is effectively eliminated with safe remifentanil doses. However, the safety margin in deep sedation-analgesia would be narrowed in minimising not only nociceptive responses, but also arousal-related biological stress.

As the world becomes more urbanized, more people become exposed to traffic and the risks associated with a higher exposure to road traffic noise increase. Excessive exposure to environmental noise could potentially interfere with functional maturation of the auditory brain in developing individuals. The aim of the present study was to assess the association between exposure to annual average road traffic noise (LAeq) in schools and functional connectivity of key elements of the central auditory pathway in schoolchildren. A total of 229 children from 34 representative schools in the city of Barcelona with ages between 8 and 12 years (49.2% girls) were evaluated. LAeq was obtained as the mean of 2-consecutive day measurements inside classrooms before lessons started following standard procedures to obtain an indicator of long-term road traffic noise levels. A region-of-interest functional connectivity Magnetic Resonance Imaging (MRI) approach was adopted. Functional connectivity maps were generated for the inferior colliculus, medial geniculate body of the thalamus and primary auditory cortex as key levels of the central auditory pathway. Road traffic noise in schools was significantly associated with stronger connectivity between the inferior colliculus and a bilateral thalamic region adjacent to the medial geniculate body, and with stronger connectivity between the medial geniculate body and a bilateral brainstem region adjacent to the inferior colliculus. Such a functional connectivity strengthening effect did not extend to the cerebral cortex. The anatomy of the association implicating subcortical relays suggests that prolonged road traffic noise exposure in developing individuals may accelerate maturation in the basic elements of the auditory pathway. Future research is warranted to establish whether such a faster maturation in early pathway levels may ultimately reduce the developing potential in the whole auditory system. This research received funding from the following sources: European Research Council (ERC) Grant Agreement No 268479 - BREATHE project (JS). The European Union’s Horizon 2020 research and innovation program under grant agreement No 874724 -Equal-life (MF). Equal-life is part of the European Human Exposome Network. The Beatriu de Pinós Programme and the Ministry of Research and Universities of the Government of Catalonia (2017 BP 00173, MF). The European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 886121 (IR). European Research Council Grant agreement number 785994 (H2020) – AirNB (JS). We also acknowledge support from the Spanish Ministry of Science and Innovation and State Research Agency through the “Centro de Excelencia Severo Ochoa 2019–2023” Program (CEX2018-000806-S, https://www.ciencia.gob.es/site-web/en/Organismos-y-Centros/Centros-y-Unidades-de-Excelencia.html, and the Generalitat de Catalunya through the CERCA Program (https://cerca.cat/).

Imaging studies on neuronal network formation provide relevant information as to how the brain matures during adolescence. We used a novel imaging approach combining well-established MRI measures of local functional connectivity that jointly provide qualitatively different information relating to the functional structure of the cerebral cortex. To investigate the adolescent transition into adulthood, we comparatively assessed 169 preadolescents aged 8-12 years and 121 healthy adults. Whole-brain functional connectivity maps were generated using multi-distance measures of intracortical neural activity coupling defined within iso-distant local areas. Such Iso-Distant Average Correlation (IDAC) measures therefore represent the average temporal correlation of a given brain unit, or voxel, with other units situated at increasingly separated iso-distant intervals. The results indicated that between-group differences in the functional structure of the cerebral cortex are extensive and implicate part of the lateral prefrontal cortex, a medial frontal/anterior cingulate region, the superior parietal lobe extending to the somatosensory strip and posterior cingulate cortex, and local connections within the visual cortex, hippocampus, amygdala and insula. We thus provided detail of the cerebral cortex functional structure maturation during the transition to adulthood, which may serve to establish more accurate links between adolescent performance gains and cerebral cortex maturation. Remarkably, our study provides new information as to the cortical maturation processes in prefrontal areas relevant to executive functioning and rational learning, medial frontal areas playing an active role in the cognitive appraisal of emotion and anxiety, and superior parietal cortices strongly associated with bodily self-consciousness in the context of body image formation. This work was supported in part by the European Research Council under the ERC [grant number 268479] – the BREATHE project and the Carlos III Health Institute grants PI13/01958 and PI16/00889.

After falling asleep, the brain needs to detach from waking activity and reorganize into a functionally distinct state. A functional MRI (fMRI) study has recently revealed that the transition to unconsciousness induced by propofol involves a global decline of brain activity followed by a transient reduction in cortico-subcortical coupling. We have analyzed the relationships between transitional brain activity and breathing changes as one example of a vital function that needs the brain to readapt. Thirty healthy participants were originally examined. The analysis involved the correlation between breathing and fMRI signal upon loss of consciousness. We proposed that a decrease in ventilation would be coupled to the initial decline in fMRI signal in brain areas relevant for modulating breathing in the awake state, and that the subsequent recovery would be coupled to fMRI signal in structures relevant for controlling breathing during the unconscious state. Results showed that a slight reduction in breathing from wakefulness to unconsciousness was distinctively associated with decreased activity in brain systems underlying different aspects of consciousness including the prefrontal cortex, the default mode network and somatosensory areas. Breathing recovery was distinctively coupled to activity in deep brain structures controlling basic behaviors such as the hypothalamus and amygdala. Activity in the brainstem, cerebellum and hippocampus was associated with breathing variations in both states. Therefore, our brain maps illustrate potential drives to breathe, unique to wakefulness, in the form of brain systems underlying cognitive awareness, self-awareness and sensory awareness, and to unconsciousness involving structures controlling instinctive and homeostatic behaviors.

We longitudinally assessed Down syndrome individuals at the age of risk of developing dementia to measure changes in brain anatomy and their relationship to cognitive impairment progression.Forty-two Down syndrome individuals were initially included, of whom 27 (mean age 46.8 years) were evaluable on the basis of completing the 2-year follow-up and success in obtaining good quality MRI exams. Voxel-based morphometry was used to estimate regional brain volumes at baseline and follow-up on 3D anatomical images. Longitudinal volume changes for the group and their relationship with change in general cognitive status and specific cognitive domains were mapped.As a group, significant volume reduction was identified in the substantia innominata region of the basal forebrain, hippocampus, lateral temporal cortex and left arcuate fasciculus. Volume reduction in the substantia innominata and hippocampus was more prominent in individuals whose clinical status changed from cognitively stable to mild cognitive impairment or dementia during the follow-up. Relevantly, longitudinal memory score change was specifically associated with volume change in the hippocampus, prospective memory with prefrontal lobe and verbal comprehension with language-related brain areas.Results are notably concordant with the well-established anatomical changes signaling the progression to dementia in Alzheimer's disease, despite the dense baseline pathology that developmentally accumulates in Down syndrome. This commonality supports the potential value of Down syndrome as a genetic model of Alzheimer's neurodegeneration and may serve to further support the view that Down syndrome patients are best candidates to benefit from treatment research in Alzheimer's disease.•Longitudinal changes in brain anatomy were identified in Down syndrome individuals.•Basal forebrain and hippocampal volume reductions paralleled clinical progression.•The overall anatomical pattern identified resembled Alzheimer's neurodegeneration.

Resumen Introduccion La artrosis de rodilla es causa de dolor e incapacidad funcional. Uno de los problemas para evaluar la eficacia de los analgesicos ha sido la falta de medidas objetivas de dolor, aunque la resonancia magnetica funcional (RMf) ha surgido como un medio util para objetivar la respuesta del cerebro a la estimulacion dolorosa. Hemos investigado el efecto del condroitin sulfato (CS) sobre la respuesta del cerebro a la estimulacion dolorosa de la rodilla en pacientes con artrosis mediante RMf. Metodos Veintidos pacientes recibieron CS (800 mg/dia) y 27 placebo y fueron evaluados inicialmente y despues de 4 meses de tratamiento. En cada sesion de RMf se aplico presion dolorosa sobre la interlinea de la rodilla y en la superficie de la rotula. El resultado se cuantifico como la atenuacion de la respuesta cerebral a la estimulacion dolorosa de la rodilla. Resultados La RMf de la maniobra rotuliana mostro una reduccion de la activacion en la region de la sustancia gris periacueductal del mesencefalo significativamente mayor durante el tratamiento con CS que en la condicion de placebo. El grupo de CS, pero no el de placebo, mostro ademas una reduccion de la activacion en la representacion cortical de la pierna tras el tratamiento. No se observaron efectos del CS con presion dolorosa sobre la interlinea de la rodilla. Conclusiones La RMf fue sensible para objetivar los efectos del CS sobre la respuesta del cerebro a la presion dolorosa sobre el cartilago rotuliano-femoral, que es un resultado coherente con la accion conocida del CS sobre la regeneracion de los condrocitos. El presente trabajo muestra nuevamente la utilidad de la RMf para objetivar los efectos del tratamiento en el dolor de origen artrosico.

Children are more vulnerable to the effects of environmental elements due to their active developmental processes. Exposure to urban air pollution has been associated with poorer cognitive performance, which is thought to be a result of direct interference with brain maturation. We aimed to assess the extent of such potential effects of urban pollution on child brain maturation using general indicators of vehicle exhaust measured in the school environment and a comprehensive imaging evaluation. A group of 263 children, aged 8 to 12years, underwent MRI to quantify regional brain volumes, tissue composition, myelination, cortical thickness, neural tract architecture, membrane metabolites, functional connectivity in major neural networks and activation/deactivation dynamics during a sensory task. A combined measurement of elemental carbon and NO2 was used as a putative marker of vehicle exhaust. Air pollution exposure was associated with brain changes of a functional nature, with no evident effect on brain anatomy, structure or membrane metabolites. Specifically, a higher content of pollutants was associated with lower functional integration and segregation in key brain networks relevant to both inner mental processes (the default mode network) and stimulus-driven mental operations. Age and performance (motor response speed) both showed the opposite effect to that of pollution, thus indicating that higher exposure is associated with slower brain maturation. In conclusion, urban air pollution appears to adversely affect brain maturation in a critical age with changes specifically concerning the functional domain. This work was supported by the European Research Council under the ERC [grant number 268479]—the BREATHE project. The Agency of University and Research Funding Management of the Catalonia Government participated in the context of Research Group SGR2014-1673.

Background Functional neuroimaging studies have provided consistent support for the idea that obsessive-compulsive disorder (OCD) is associated with disturbances of brain corticostriatal systems. However, in general, these studies have not sought to account for the disorder's prominent clinical heterogeneity. Methods To address these concerns, we investigated the influence of major OCD symptom dimensions on brain corticostriatal functional systems in a large sample of OCD patients (n = 74) and control participants (n = 74) examined with resting-state functional magnetic resonance imaging. We employed a valid method for mapping ventral and dorsal striatal functional connectivity, which supported both standard group comparisons and linear regression analyses with patients' scores on the Dimensional Yale-Brown Obsessive-Compulsive Scale. Results Consistent with past findings, patients demonstrated a common connectivity alteration involving the ventral striatum and orbitofrontal cortex that predicted overall illness severity levels. This common alteration was independent of the effect of particular symptom dimensions. Instead, we observed distinct anatomical relationships between the severity of symptom dimensions and striatal functional connectivity. Aggression symptoms modulated connectivity between the ventral striatum, amygdala, and ventromedial frontal cortex, while sexual/religious symptoms had a specific influence on ventral striatal-insular connectivity. Hoarding modulated the strength of ventral and dorsal striatal connectivity with distributed frontal regions. Conclusions Taken together, these results suggest that pathophysiological changes among orbitofrontal-striatal regions may be common to all forms of OCD. They suggest that a further examination of certain dimensional relationships will also be relevant for advancing current neurobiological models of the disorder.

Although the fear of being scrutinized by others in a social context is a key symptom in social anxiety disorder (SAD), the neural processes underlying the perception of scrutiny have not previously been studied by func- tional magnetic resonance imaging (fMRI). We used fMRI to map brain activation during a perception-of- scrutiny task in 20 SAD patients and 20 controls. A multi-dimensional analytic approach was used. Scrutiny perception was mediated by activation of the medial frontal cortex, insula – operculum region and cerebellum, and the additional recruitment of visual areas and the thalamus in patients. Between-group comparison demonstrated signi fi cantly enhanced brain activation in patients in the primary visual cortex and cerebellum. Functional connectivity mapping demonstrated an abnormal connectivity between regions underlying general arousal and attention. SAD patients showed signi fi cantly greater task-induced functional connectivity in the thalamo-cortical and the fronto-striatal circuits. A statistically signi ficant increase in task-induced functional connectivity between the anterior cingulate cortex and scrutiny-perception-related regions was observed in the SAD patients, suggesting the existence of enhanced behavior-inhibitory control. The presented data indicate that scrutiny perception in SAD enhances brain activity in arousal–attention systems,suggesting that fMRI may be a useful tool to explore such a behavioral dimension.

Background Whole-brain imaging approaches may contribute to the characterization of neuroanatomic alterations in major depression, especially in clinically homogenous patient groups such as those with melancholic features. We assessed brain anatomic alterations, both cross-sectionally and longitudinally, in patients with melancholic depression using a whole-brain voxel-wise approach. Methods Whole-brain magnetic resonance images were collected from a relatively aged sample of 70 consecutively recruited major depressive disorder inpatients with melancholic features and from a group of 40 healthy control subjects. All patients were clinically followed for at least 2 years, and a subset of 30 depressive patients and 20 control subjects were rescanned after a 7-year period. Imaging data were analyzed with voxel- and tensor-based morphometry techniques. Results Melancholic patients showed gray matter reductions in the left insula and white matter increases in the upper brainstem tegmentum. Male patients showed gray matter decreases in the right thalamus, and periventricular white matter reductions were specifically observed in older patients. Volume decreases in the left insula, hippocampus, and lateral parietal cortex predicted a slower recovery after treatment initiation. In longitudinal assessment, white matter of the upper brainstem tegmentum showed a different temporal evolution between groups. Additionally, bilateral gray matter reductions in the insulae were associated with the number of relapses during follow-up. Conclusions Structural alterations were identified in regions potentially related to relevant aspects of melancholia pathophysiology. Longitudinal analyses indicated region-specific interactions of baseline alterations with age as well as a significant association of clinical severity with focal changes occurring over time.

Resumen El dolor es una experiencia subjetiva dificilmente evaluable de forma objetiva por su variada expresion. Se define como una compleja experiencia sensorio-emocional, modulada por factores cognitivos, y que involucra un amplio sistema neural. La neuroimagen funcional ha contribuido a definir este circuito neural en controles sanos y en pacientes con un sindrome de dolor agudo o cronico implicado en la modulacion, la percepcion y la respuesta de una experiencia dolorosa. Sin embargo, la activacion funcional de la “matriz neural” del dolor puede modularse, bien por un componente sensorial bien por un componente emocional. Este ultimo podria mediatizar la intensidad a partir de la que un estimulo se percibe como doloroso. Este umbral parece ser menor en pacientes con diagnostico clinico de fibromialgia (FM), pacientes que generan una anormal activacion funcional del circuito neural del dolor, evaluada mediante resonancia magnetica funcional (RMf), lo que se considera un sindrome de susceptibilidad central. En apoyo a esta explicacion etiologica, los estudios de RMf constatan que una proporcion significativa de pacientes con FM presenta una consistente y anormal activacion de la “matriz neural” del dolor a estimulos de baja intensidad. Adicionalmente, se constata una importante y una significativa activacion funcional con una duracion temporal de activacion cerebral superior a la del estimulo nociceptivo aplicado y, especificamente, en las areas neuroanatomicas implicadas en la dimension emocional del dolor. En consecuencia, la RMf permite observar, de manera incruenta, la anormal respuesta funcional cerebral a un estimulo nociceptivo en pacientes con diagnostico clinico de FM.

Pain is a highly subjective experience that is difficult to measure objectively due to its varied expression. It is defined as a complex sensory-emotional experience; it is modulated by cognitive factors and involves a broad neural system. Functional neuroimaging has helped to define that neural circuit involved in the perception, modulation and response to painful experience, both in healthy controls and in patients with acute and chronic pain disorders. However, functional activation of the so-called “pain matrix” may also be differentially modulated by sensory and emotional processing components. The latter, for example, can influence the intensity to which a stimulus is perceived as painful. Such a threshold seems to be lower in patients with clinical diagnosis of fibromyalgia (FM) and has been linked to an abnormal pattern of activation of the “pain matrix” when assessed with functional magnetic resonance imaging (fMRI), considering a “syndrome of central susceptibility.” Supporting an etiological explanation for FM, studies have noted that a significant proportion of patients with FM demonstrate this abnormal pattern of activation to stimuli of low intensity. Additionally, there is an important and significant temporal dimension to this activation pattern observed in FM patients, where areas commonly associated with the emotional experience of pain show a prolonged response to painful stimuli compared to healthy subjects. Accordingly, fMRI may assist in objectifying the experience of pain in patients with FM in response to nociceptive stimulation.

The high comorbidity of obsessive-compulsive disorder (OCD) with major depressive disorder (MDD) suggests common neurobiological substrates. We assessed the contribution of lifetime MDD to brain structural alterations in OCD using magnetic resonance imaging. OCD patients with (n=33) or without (n=39) lifetime MDD, and 72 control subjects were assessed. Comparative region of interest (ROI) analyses assessed the contribution of lifetime MDD to gray matter volume alterations in OCD patients. Interregional correlations of gray matter volume were also examined and voxelwise analyses were performed to identify alterations in other brain regions. OCD patients with lifetime MDD showed a larger reduction of medial orbitofrontal cortex (mOFC) gray matter volume. Both OCD groups showed distinct correlations of mOFC gray matter volume with other relevant brain regions. For patients with MDD, this involved the medial frontal gyrus, and right insula and amygdala regions, whereas for those OCD patients without MDD, the rostral anterior cingulate cortex was involved. Our findings support existing evidence suggesting a non-specific involvement of mOFC alterations in a range of neuropsychiatric disorders. Nevertheless, volume reduction in this region, together with an abnormal pattern of interregional correlations with other emotion-relevant brain areas, may contribute to explain the diathesis for MDD comorbidity in OCD.

Structural neuroimaging studies have reported a variety of brain alterations between groups of obsessive-compulsive disorder (OCD) patients and healthy controls. However, the large heterogeneity in discrete anatomical measures that exists among patients prevents a clear discrimination of single patients from healthy subjects. This reduces the potential clinical applicability of structural neuroimaging studies. In the present study we assessed the feasibility of identifying OCD patients on the basis of whole-brain anatomical alterations. Whole-brain magnetic resonance images were collected from two consecutive samples of OCD outpatients (n=72 and n=30), and control subjects (n=72 and n=30). We computed the whole-brain (voxel-wise) pattern of structural difference between OCD patients and control subjects at the group level. A single expression value of this difference pattern was calculated for each subject, expressing their degree of 'OCD-like' anatomical alteration. Accuracy of patient classification based on these expression values was assessed using two validation approaches. Firstly, using a cross-validation method, we obtained a high classification accuracy (average of the sensitivity and specificity indices) of 93.1%. In a second assessment, which classified new groups of OCD patients and control subjects, overall accuracy was lower at 76.6%. Individual expression values for OCD patients were significantly correlated with overall symptom severity as measured by the Y-BOCS scale. Our results suggest that OCD patients can be identified on the basis of whole-brain structural alterations, although the accuracy of our approach may be limited by the inherent variability of psychiatric populations. Nevertheless, the anatomical characterization of individual patients may ultimately provide the psychiatrist with relevant biological information.

Introduccion El dolor es una experiencia subjetiva dificilmente evaluable por su variada expresion. Actualmente, la resonancia magnetica funcional (RMf) permite objetivar la respuesta cerebral al estimulo doloroso. Objetivo Evaluar la respuesta cerebral al dolor en pacientes con dolor cronico esencial generalizado diagnosticados de fibromialgia (FM). Sujetos y metodos Se administro un estimulo doloroso por presion mecanica a 15 pacientes con FM y 11 controles durante la adquisicion de RMf. Se realizaron diversos ensayos de activacion variando la presion ejercida sobre una superficie de 1 cm 2 del dedo pulgar. Resultados Durante la adquisicion de RMf, la aplicacion de una presion mecanica de 4 kg no ocasiono molestias relevantes en ningun sujeto control. Contrariamente, todos los pacientes, excepto uno, refirieron dolor moderado-grave con este estimulo. La RMf puso de manifiesto que, con poca presion (4 y 5 kg), es excepcional la activacion de regiones distintas al area sensitivomotora primaria contralateral al dedo estimulado en los sujetos control. Sin embargo, 5 pacientes (p = 0,027), a 4 kg de presion, y 7 (p = 0,030), a 5 kg, activaron las regiones cerebrales conocidas como mediadoras de la respuesta al dolor (area sensitivomotora primaria, corteza parietal, insula y region del cingulo anterior). Conclusiones Los resultados sugieren que una proporcion significativa de pacientes diagnosticados de FM y con bajo umbral doloroso presentan una consistente respuesta cerebral al dolor con estimulos mecanicos de baja intensidad, mientras que en otra parte de los casos el cerebro responde de forma similar a los sujetos control.

This study focused on investigating a possible relationship between interindividual variability in the morphology of the cingulate gyrus and behavioral styles. Using magnetic resonance images obtained from 100 healthy young volunteers (50 women and 50 men), we measured the surface area of the anterior cingulate gyrus and related it to the scores on the Temperament and Character Inventory. Anatomical data revealed that hemispheric asymmetry in the anterior cingulate gyrus surface area was very common (83% of cases) and that a prominent right anterior cingulate was more frequent in women than in men. In the correlational analysis, surface measurements of the right anterior cingulate gyrus accounted for a 24% score variance in Harm Avoidance. Both women and men with larger right anterior cingulate described themselves as experiencing greater worry about possible problems, fearfulness in the face of uncertainty, shyness with strangers, and fatigability. Furthermore, women reported overall higher scores in Harm Avoidance than men; these gender differences were largely explained by gender differences in the right anterior cingulate area in a covariate analysis. Our observations suggest that a large right anterior cingulate is related to a temperamental disposition to fear and anticipatory worry in both genders and that a higher prevalence of these traits in women may be coupled with a greater expansion of this brain region.

The Sylvian fissure region gathers lateral frontotemporal cortices and subcortical structures that are frequently disturbed in patients with mood disorders. We have investigated possible CSF space changes in this brain region in severe melancholic depression. Fifty-seven patients and 37 control subjects received three-dimensional MRI. CSF volumes were obtained for cerebral CSF, lateral ventricles, and both Sylvian fissure regions. As a group, patients showed a significant CSF space enlargement that was prominent around the Sylvian fissure, particularly in the left hemisphere. Likewise, evident leftward asymmetry was more frequent in the patient group (patients 31.6%, controls 2.7%). The combination of CSF space enlargement and the pattern of Sylvian CSF asymmetry predicted the patient condition with 62.2% specificity and 82.5% sensitivity. We conclude that, in the context of a broad severity spectrum of imaging alterations in severe melancholic depression, asymmetrical CSF space enlargement may be evident in the Sylvian fissure region.

Functional imaging has consistently shown that attention-related areas of medial frontal and posterior parietal cortices are active during the attentional conflict induced by color naming in the presence of distracting words (Stroop task). Such studies, however, have provided few details of the correlational nature between observed regional brain activations and reaction time delay occurring in this situation. We analyzed the effect of medial frontal and posterior parietal lesions on the Stroop response in a group of patients with multiple sclerosis, a neurological disorder in which Stroop response speed is affected to varying degrees. Forty-five patients were assessed using a computer-presented verbal version of the Stroop task and specific MRI protocol. Demyelination areas were measured on five anatomical divisions of the medial frontal white matter and on white matter of the posterior parietal lobe. We found that a combination of frontal and parietal lesion measurements accounted for 45% of the Stroop interference time variance. Patients with more right frontal than left parietal demyelination showed slowed Stroop responses, whereas the predominance of lesions in the left posterior parietal region was associated with a reduced Stroop interference. These results may contribute to defining the specific participation of these attention-related brain areas in the conflict of attention represented by the Stroop paradigm. They also help to explain the variability of the Stroop effect in multiple sclerosis patients and suggest that the Stroop test does not assess just a single cognitive operation, but rather the combined effect of anatomically segregated neural processes.

This study was conducted to further establish the significance of the previously reported association between depressive symptoms and demyelinating lesions in the region of the left arcuate fasciculus in multiple sclerosis patients. The Beck Depression Inventory (BDI) was broken down into its main symptom categories on the basis of well-established factor analyses from the literature, and the correlation pattern between the resulting BDI subscores and lesion measurements was analyzed. We found that lesions of the left arcuate fasciculus region were selectively associated with BDI items expressing patients' Affective Symptoms and Somatic Complaints. Specifically, lesion measurements from this brain location accounted for 26% of symptom score variance of the BDI part that includes only these two factors. Performance Difficulties and Cognitive Distortions were not consistently associated with the lesion measurement. Performance Difficulties, however, showed a high correlation with the neurologic deficit detected in the physical examination. These results show that lesions in the left arcuate fasciculus region are associated with the core of the depressive syndrome rather than marginal symptoms and, thus, further suggest that this left suprainsular brain region involves white matter tracts relevant to mood regulation.

Focal hand dystonia in musicians is a strongly task-related movement disorder. Typically, symptoms become apparent only when players execute specific overpracticed skilled exercises on their instrument. We therefore examined five guitarists with functional MRI during dystonic symptom provocation by means of an adapted guitar inside the magnet. The activation patterns obtained in comparable nondystonic guitarists and in the study patients when performing normal-hand exercise served as references. A 1.5-T system equipped with echo-speed gradients and single-shot echoplanar imaging software was used. Data acquisition was centered on the cortical motor system encompassed in eight contiguous slices. Dystonic musicians compared with both control situations showed a significantly larger activation of the contralateral primary sensorimotor cortex that contrasted with a conspicuous bilateral underactivation of premotor areas. Our results coincide with studies of other dystonia types in that they show an abnormal recruitment of cortical areas involved in the control of voluntary movement. However, they do suggest that the primary sensorimotor cortex, rather than being underactive in idiopathic dystonic patients, may be overactive when tested during full expression of the task-induced movement disorder.

Background: Functional imaging studies have demonstrated abnormal patterns of brain activity in obsessive–compulsive disorder, which consistently suggest the alteration of frontal lobe functioning. We performed a brain activation study in obsessive–compulsive disorder using a cognitive task involving the frontal lobes. Methods: Twenty patients and 20 healthy control subjects were assessed with functional magnetic resonance imaging during a phonologically guided word generation task. The study analysis was based on the comparison of group average time-course functional changes occurring at the site of largest frontal cortex activation during alternating rest and task periods. Results: In terms of relative signal changes, patients showed a significantly greater activation during word generation and a defective suppression of this activation during the following rest period. Both abnormal imaging findings significantly correlated with the severity of the clinical process assessed by the Yale–Brown Obsessive–Compulsive Scale. Conclusions: The results indicate that functional magnetic resonance imaging during cognitive challenge may be useful to reveal distinctive features of latent brain dysfunction in obsessive–compulsive disorder.

Resumen La localizacion neuroanatomica de las lesiones cerebrales que cursan con un sindrome afasico ha alcanzado un mayor indice de precision gracias a las tecnicas de neuroimagen, en concreto con la tomografia computadorizada (TC) y la resonancia magnetica (RM). Por ello resulta de interes para la logopeda conocer e interpretar las imagenes de la TC y con ello detallar la localizacion y extension de la lesion causante del sindrome afasico. Ello junto con la exploracion linguistica puede ayudar a establecer planes de rehabilitacion del lenguaje y evidentemente contribuye al pronostico. Es de notable interes tanto el conocer las funciones linguisticas preservadas y alteradas en un determinado paciente afasico como el determinar el tejido cerebral intacto con capacidad de reorganizar lenguaje. En la presente revision se exponen los esquemas de localizacion sugeridos por Naeser que facilitan la tarea de identificacion de las zonas lesionadas en la TC. Asimismo, se revisan las diferentes hipotesis que postulan las areas o zonas neuroanatomicas lesionadas claves para la produccion de los diferentes sindromes afasicos.

Resumen Los mecanismos neuronales o estructuras cerebrales implicadas en el deficit del desarrollo de las habilidades linguisticas receptivas o expresivas todavia permanecen sin un amplio consenso de conocimiento. Se ha explorado y supervisado evolutivamente desde una amplia perspectiva neuropsicologica y mediante estudios de neuroimagen, un paciente a los 10 y 17 anos de edad, el cual presentaba una disfasia de tipo expresivo o fonologica-sintactica mixta. La evaluacion neuropsicologica permite detectar un marcado deficit de las capacidades de expresion versus unas capacidades de comprension relativamente preservadas, en ausencia de factores casuales, tales como perdida auditiva, alteracion neurologica por lesion cerebral, retraso mental o trastorno psiquiatrico. El estudio de neuroimagen mediante las tecnicas de TC y RM no ponen de manifiesto ninguna lesion estructural macrocelular, que pueda explicar el cuadro, de acuerdo con los resultados de estudios precedentes. A la luz de tales resultados, se considera que el presente caso es un cuadro prototipico de disfasia o afasia del desarrollo.