Working Memory Deficits After Lesions Involving the Supplementary Motor Area.

Published: 23 May 2018The Supplementary Motor Area (SMA)—located in the superior and medial aspects of the superior frontal gyrus—is a preferential site of certain brain tumors and arteriovenous malformations, which often provoke the so-called SMA syndrome. The bulk of the literature studying this syndrome has focused on two of its most apparent symptoms: contralateral motor and speech deficits. Surprisingly, little attention has been given to working memory (WM) even though neuroimaging studies have implicated the SMA in this cognitive process. Given its relevance for higher-order functions, our main goal was to examine whether WM is compromised in SMA lesions. We also asked whether WM deficits might be reducible to processing speed (PS) difficulties. Given the connectivity of the SMA with prefrontal regions related to executive control (EC), as a secondary goal we examined whether SMA lesions also hampered EC. To this end, we tested 12 patients with lesions involving the left (i.e., the dominant) SMA. We also tested 12 healthy controls matched with patients for socio-demographic variables. To ensure that the results of this study can be easily transferred and implemented in clinical practice, we used widely-known clinical neuropsychological tests: WM and PS were measured with their respective Wechsler Adult Intelligence Scale indexes, and EC was tested with phonemic and semantic verbal fluency tasks. Non-parametric statistical methods revealed that patients showed deficits in the executive component of WM: they were able to sustain information temporarily but not to mentally manipulate this information. Such WM deficits were not subject to patients’ marginal PS impairment. Patients also showed reduced phonemic fluency, which disappeared after controlling for the influence of WM. This observation suggests that SMA damage does not seem to affect cognitive processes engaged by verbal fluency other than WM. In conclusion, WM impairment needs to be considered as part of the SMA syndrome. These findings represent the first evidence about the cognitive consequences (other than language) of damage to the SMA. Further research is needed to establish a more specific profile of WM impairment in SMA patients and determine the consequences of SMA damage for other cognitive functions.MH was supported by the Ramón y Cajal (RYC-2016-19477) research program (Spanish Ministry of Economy, Industry, and Competitiveness). MH also acknowledges financial support from the Diputación Foral de Gipuzkoa/Gipuzkoako Foru Aldundia (Programa FellowsGipuzkoa de atracción y retención de talento)

The black box of global aphasia: Neuroanatomical underpinnings of remission from acute global aphasia with preserved inner language function

Objective We studied an unusual case of global aphasia (GA) occurring after brain tumor removal and remitting one-month after surgery. After recovering, the patient reported on her experience during the episode, which suggested a partial preservation of language abilities (such as semantic processing) and the presence of inner speech (IS) despite a failure in overt speech production. Thus, we explored the role of IS and preserved language functions in the acute phase and investigated the neuroanatomical underpinnings of this severe breakdown in language processing. Method A neuropsychological and language assessment tapping into language production, comprehension, attention and working memory was carried out both before and three months after surgery. In the acute stage a simplified protocol was tailored to assess the limited language abilities and further explore patient's performance on different semantic tasks. The neuroanatomical dimension of these abrupt changes was provided by perioperative structural neuroimaging. Results Language and neuropsychological performance were normal/close to normal both before and three months after surgery. In the acute stage, the patient presented severe difficulties with comprehension, production and repetition, whereas she was able to correctly perform tasks that requested conceptual analysis and non-verbal operations. After recovering, the patient reported that she had been able to internally formulate her thoughts despite her overt phonological errors during the episode. Structural neuroimaging revealed that an extra-axial blood collection affected the middle frontal areas during the acute stage and that the white matter circuitry was left-lateralized before surgery. Conclusions We deemed that the global aphasia episode was produced by a combination of the post-operative extra-axial blood collection directly impacting left middle frontal areas and a left-lateralization of the arcuate and/or uncinated fasciculi before surgery. Additionally, we advocate for a comprehensive evaluation of linguistic function that includes the assessment of IS and non-expressive language functions in similar cases

Working Memory Deficits After Lesions Involving the Supplementary Motor Area

The Supplementary Motor Area (SMA)¿located in the superior and medial aspects of the superior frontal gyrus¿is a preferential site of certain brain tumors and arteriovenous malformations, which often provoke the so-called SMA syndrome. The bulk of the literature studying this syndrome has focused on two of its most apparent symptoms: contralateral motor and speech deficits. Surprisingly, little attention has been given to working memory (WM) even though neuroimaging studies have implicated the SMA in this cognitive process. Given its relevance for higher-order functions, our main goal was to examine whether WM is compromised in SMA lesions. We also asked whether WM deficits might be reducible to processing speed (PS) difficulties. Given the connectivity of the SMA with prefrontal regions related to executive control (EC), as a secondary goal we examined whether SMA lesions also hampered EC. To this end, we tested 12 patients with lesions involving the left (i.e., the dominant) SMA. We also tested 12 healthy controls matched with patients for socio-demographic variables. To ensure that the results of this study can be easily transferred and implemented in clinical practice, we used widely-known clinical neuropsychological tests: WM and PS were measured with their respective Wechsler Adult Intelligence Scale indexes, and EC was tested with phonemic and semantic verbal fluency tasks. Non-parametric statistical methods revealed that patients showed deficits in the executive component of WM: they were able to sustain information temporarily but not to mentally manipulate this information. Such WM deficits were not subject to patients' marginal PS impairment. Patients also showed reduced phonemic fluency, which disappeared after controlling for the influence of WM. This observation suggests that SMA damage does not seem to affect cognitive processes engaged by verbal fluency other than WM. In conclusion, WM impairment needs to be considered as part of the SMA syndrome. These findings represent the first evidence about the cognitive consequences (other than language) of damage to the SMA. Further research is needed to establish a more specific profile of WM impairment in SMA patients and determine the consequences of SMA damage for other cognitive functions

The role of the anterior insular cortex in self-monitoring: a novel study protocol with electrical stimulation mapping and functional magnetic resonance imaging

Becoming aware of one's own states is a fundamental aspect for self-monitoring, allowing us to adjust our beliefs of the world to the changing context. Previous evidence points out to the key role of the anterior insular cortex (aIC) in evaluating the consequences of our own actions, especially whenever an error has occurred. In the present study, we propose a new multimodal protocol combining electrical stimulation mapping (ESM) and functional magnetic resonance imaging (fMRI) to explore the functional role of the aIC for self-monitoring in patients undergoing awake brain surgery. Our results using a modified version of the Stroop task tackling metacognitive abilities revealed new direct evidence of the involvement of the aIC in monitoring our performance, showing increased difficulties in detecting action-outcome mismatches when stimulating a cortical site located at the most posterior part of the aIC as well as significant BOLD activations at this region during outcome incongruences for self-made actions. Based on these preliminary results, we highlight the importance of assessing the aIC's functioning during tumor resection involving this region to evaluate metacognitive awareness of the self in patients undergoing awake brain surgery. In a similar vein, a better understanding of the aIC's role during self-monitoring may help shed light on action/outcome processing abnormalities reported in several neuropsychiatric disorders such as schizophrenia, anosognosia for hemiplegia or major depression

Risk factors for surgical site infection after craniotomy: a prospective cohort study

Background: Although surgical site infection after craniotomy (SSI-CRAN) is a serious complication, risk factors for its development have not been well defined. We aim to identify the risk factors for developing SSI-CRAN in a large prospective cohort of adult patients undergoing craniotomy. Methods: A series of consecutive patients who underwent craniotomy at a university hospital from January 2013 to December 2015 were prospectively assessed. Demographic, epidemiological, surgical, clinical and microbiological data were collected. Patients were followed up in an active post-discharge surveillance programm e for up to one year after surgery. Multivariate analysis was carried out to identify independent risk factors for SSI-CRAN. Results: Among the 595 patients who underwent craniotomy, 91 (15.3%) episodes of SSI-CRAN were recorded, 67 (73.6%) of which were organ/space. Baseline demographic characteristics were similar among patients who developed SSI-CRAN and those who did not. The most frequent causative Gram-positive organisms were Cutibacterium acnes (23.1%) and Staphylococcus epidermidis (23.1%), whereas Enterobacter cloacae (12.1%) was the most commonly isolated Gram-negative agent. In the univariate analysis the factors associated with SSI-CRAN were ASA score > 2 (48.4% vs. 35.5% in SSI-CRAN and no SSI-CRAN respectively, p = 0.025), extrinsic tumour (28.6% vs. 19.2%, p = 0.05), and re-intervention (4.4% vs. 1.4%, p =  2 (AOR: 2.26, 95% CI: 1.32-3.87; p = .003) and re-intervention (OR: 8.93, 95% CI: 5.33-14.96; p < 0.001) were the only factors independently associated with SSI-CRAN. Conclusion: The risk factors and causative agents of SSI-CRAN identified in this study should be considered in the design of preventive strategies aimed to reduce the incidence of this serious complication

Radiocirugía estereotáctica para el tratamiento de la epilepsia, el temblor esencial, la enfermedad de Parkinson, la neuralgia del glosofaríngeo y del trigémino: síntesis de su eficacia, efectividad, seguridad y eficiencia

Radiocirugia estereotàctica; Tractament; EficàciaRadiocirugía estereotáctica; Tratamiento; EficaciaStereotactic radiosurgery; Treatment; EffectivenessEl objetivo principal del informe es evaluar la seguridad, la eficacia, la efectividad clínica y el costeefectividad de la radiocirugía estereotáctica frente al tratamiento habitual para la epilepsia, el temblor esencial, el temblor asociado a la enfermedad de Parkinson y las neuralgias del glosofaríngeo y del trigémino. Se consideran cuando estas patologías son farmacorresistentes/refractarias.The aim of this report is to evaluate the safety, efficacy, clinical effectiveness and cost-effectiveness of stereotactic radiosurgery versus standard treatment for epilepsy, essential tremor, tremor associated with Parkinson’s disease, and glossopharyngeal and trigeminal neuralgias, when these pathologies are drug-resistant/refractoryL’objectiu d’aquest informe és avaluar la seguretat, l’eficàcia, l’efectivitat clínica i el cost-efectivitat de la radiocirurgia estereotàctica davant del tractament habitual per a l’epilèpsia, el tremolor essencial, el tremolor associat a la malaltia de Parkinson i les neuràlgies del glossofaringi i del trigemin, quan aquestes patologies són farmacoresistents/refractàrie

Base de datos multicéntrica de hemorragia subaracnoidea espontánea del Grupo de Trabajo de Patología Vascular de la Sociedad Española de Neurocirugía: presentación,criterios de inclusión y desarrollo de una base de datos en internet = Spontaneous Subarachnoid Haemorrhage multicenter database from the Group for the Study of Vascular Pathology of the Spanish Society for Neurosurgery: Presentation, inclusion criteria and development of an internet-based registry

Introducción. La hemorragia subaracnoidea (HSA) continúa siendo una de las enfermedades de interés neuroquirúrgico de más alta morbilidad y mortalidad. Su estudio es clave a la hora de mejorar la atención de estos enfermos en nuestro medio. Con este fin el Grupo de Trabajo de Patología Vascular de la SENEC decidió la creación de una base de datos multicéntrica para su estudio. Material y métodos. Se incluyen en esta base de datos todos los casos de hemorragia subaracnoidea espontánea ingresados en los centros participantes de forma prospectiva desde Noviembre del año 2004 hasta Noviembre del 2007. Se decidieron de forma consensuada los campos a recoger incluyendo edad, antecedentes personales, características clínicas, características radiológicas y del aneurisma, tipo de tratamiento y complicaciones de la enfermedad, evolución según la escala de evolución de Glasgow (GOS) al alta y a los seis meses así como el resultado angiográfico del tratamiento. Todos los campos se recogieron en un formulario rellenable a través de una página web segura. Resultados. En los tres años en los que ha estado activa la base se han recogido un total de 1149 casos de HSA espontánea recogidos por 14 centros participantes. Se ha estimado que es necesario aproximadamente un tiempo de 3.4 minutos para rellenar cada caso. En cuanto a sus características generales la serie es similar a otras series hospitalarias no seleccionadas. La edad media de los enfermos incluidos es de unos 55 años y la relación mujer:hombre 4:3. En cuanto a la gravedad del sagrado inicial un 32% de los enfermos se encontraba en mal grado clínico (WFNS = 4 ó 5). El 5% de los pacientes fallecieron antes de realizarse una angiografía que confirmara el origen aneurismático del sangrado. Se confirmó el origen aneurismático en el 76% de los pacientes mientras que en el 19% no se encontró ninguna lesión vascular responsable del sangrado, siendo clasificados como HSA idiopática. En los pacientes en los que se detectó un aneurisma su tratamiento fue endovascular en el 47% de los casos, quirúrgico en el 39, mixto en el 3% y no recibieron tratamiento de su aneurisma el 11% de los pacientes por fallecimiento precoz. En cuanto a su evolución, la mortalidad global de la serie se sitúa en el 22%. Sólo el 40% de los enfermos con HSA aneurismática presentaron una buena evolución (GOS=5). Conclusiones. La HSA espontánea continúa siendo una enfermedad con alta morbilidad y mortalidad. Esta base de datos puede ser un instrumento para conocer mejor sus características en nuestro medio y mejorar sus resultados, ya que se trata de una serie multicéntrica hospitalaria no seleccionada. Sería pues recomendable que esta base constituyera el germen de un registro nacional de HSA espontánea. Introduction. Subarachnoid haemorrhage is one of the most severe neurosurgical diseases. Its study is crucial for improving the care of these patients in our environment. With this goal the Group for the Study of Neurovascular Pathology of the Spanish Society for Neurosurgery (SENEC) decided to create a multicenter registry for the study of this disease. Materials and methods. In this database we have prospectively included all cases with spontaneous subarachnoid haemorrhage admitted to the participant hospitals from November 2004 to November 2007. The fields to be included in the database were selected by consensus, including age, past medical history, clinical characteristics at admission, radiological characteristics including presence or absence of an aneurysm and its size and location, type and complications of the aneurysm treatment, outcome assessed by the Glasgow Outcome Scale (GOS) at discharge and six months after the bleeding as well as the angiographic result of the aneurysm treatment. All fields were collected by means of an electronic form posted in secure web page. Results. During the three years of study a total of 1149 patients have been included by 14 Hospitals. The time needed to fill in a patient in the registry is approximately 3.4 minutes. This series of patients with spontaneous SAH is similar to other non-selected in-hospital series of SAH. The mean age of the patients is 55 years and there is a 4:3 female to male ratio. In relation to the severity of the bleeding 32% of the patients were in poor clinical grade at admission (WFNS 4 or 5). 5% of the patients died before angiography could be performed. An aneurysm was confirmed as the origin of the bleeding in 76% of the patients (aSAH), while in 19% of the patients no lesion was found in the angiographic studies and were thus classified as idiopathic subarachnoid hemorrhage (ISAH). Of those patients with aSAH, 47% were treated endovascularly, 39% surgically, 3% received a combined treatment and 11% did not receive any treatment for their aneurysm because of early death. Regarding outcome, there is a 22% mortality in the series. Only 40% of the patients with aSAH reached a good outcome at discharge (GOS = 5). Conclusions. Spontaneous SAH continues to be a disease with high morbidity and mortality. This database can be an ideal instrument for improving the knowledge about this disease in our environment and to achieve better results. It would be desirable that this database could in the future be the origin of a national registry of spontaneous SAH

Working Memory Deficits After Lesions Involving the Supplementary Motor Area

The Supplementary Motor Area (SMA)—located in the superior and medial aspects of the superior frontal gyrus—is a preferential site of certain brain tumors and arteriovenous malformations, which often provoke the so-called SMA syndrome. The bulk of the literature studying this syndrome has focused on two of its most apparent symptoms: contralateral motor and speech deficits. Surprisingly, little attention has been given to working memory (WM) even though neuroimaging studies have implicated the SMA in this cognitive process. Given its relevance for higher-order functions, our main goal was to examine whether WM is compromised in SMA lesions. We also asked whether WM deficits might be reducible to processing speed (PS) difficulties. Given the connectivity of the SMA with prefrontal regions related to executive control (EC), as a secondary goal we examined whether SMA lesions also hampered EC. To this end, we tested 12 patients with lesions involving the left (i.e., the dominant) SMA. We also tested 12 healthy controls matched with patients for socio-demographic variables. To ensure that the results of this study can be easily transferred and implemented in clinical practice, we used widely-known clinical neuropsychological tests: WM and PS were measured with their respective Wechsler Adult Intelligence Scale indexes, and EC was tested with phonemic and semantic verbal fluency tasks. Non-parametric statistical methods revealed that patients showed deficits in the executive component of WM: they were able to sustain information temporarily but not to mentally manipulate this information. Such WM deficits were not subject to patients' marginal PS impairment. Patients also showed reduced phonemic fluency, which disappeared after controlling for the influence of WM. This observation suggests that SMA damage does not seem to affect cognitive processes engaged by verbal fluency other than WM. In conclusion, WM impairment needs to be considered as part of the SMA syndrome. These findings represent the first evidence about the cognitive consequences (other than language) of damage to the SMA. Further research is needed to establish a more specific profile of WM impairment in SMA patients and determine the consequences of SMA damage for other cognitive functions

Contralateral clipping of middle cerebral artery aneurysms: rationale, indications, and surgical technique

BACKGROUND: Contralateral clipping of middle cerebral artery (MCA) aneurysms seems dangerous and ill advised but could become an important technique because of the prevalence of MCA aneurysms, the limitations of endovascular therapy, and increasing interest in less invasive techniques. OBJECTIVE: To define patient selection, surgical technique, and results with contralateral MCA aneurysm clipping. METHODS: Forty-two patients with bilateral MCA aneurysms were treated either in 1 stage with a single craniotomy and contralateral aneurysm clipping (group 1, 11 patients) or in 2 stages with bilateral craniotomy (group 2, 31 patients). Surgical technique consisted of ipsilateral sylvian fissure split, subfrontal dissection, contralateral sylvian fissure split, mobilization of medial orbital gyrus, and contralateral aneurysm clipping. RESULTS: Group 1 patients were older than group 2 patients (60.3 vs 55.4 years, respectively). Clinical presentation with subarachnoid hemorrhage was less common in group 1. Nine group 1 patients (82%) had left-sided craniotomies, and the ipsilateral aneurysm was larger than the contralateral aneurysm. All aneurysms were clipped without intraoperative complications (136 aneurysms). Mean neurosurgical charges were decreased by contralateral MCA aneurysm clipping: $39 297 in group 1 vs$57 977 in group 2. CONCLUSION: Contralateral MCA aneurysm clipping can be viewed as an extreme microsurgical technique or as a less invasive technique that spares patients a second craniotomy in the management of bilateral aneurysms. This technique is acceptable in selected patients with contralateral aneurysms that are unruptured, have simple necks, project inferiorly or anteriorly, are associated with short M1 segments, and reside in older patients with sylvian fissures widened by brain atrophy

Intraoperative Brain Mapping in Multilingual Patients: What Do We Know and Where Are We Going?

In this review, we evaluate the knowledge gained so far about the neural bases of multilingual language processing obtained mainly through imaging and electrical stimulation mapping (ESM). We attempt to answer some key questions about multilingualism in the light of recent literature evidence, such as the degree of anatomical–functional integration of two or more languages in a multilingual brain, how the age of L2-acquisition affects language organization in the human brain, or how the brain controls more than one language. Finally, we highlight the future trends in multilingual language mapping