Cronología de la investigación sobre la dinámica cerebral de Justo Gonzalo / Chronology of Justo Gonzalo’s research on brain dynamics

Introducción: El neurocientífico español Justo Gonzalo y Rodríguez-Leal (1910-1986) investiga la organización funcional de la corteza cerebral durante más de cuatro décadas. Sus hallazgos le llevan a formular una teoría neurofisiológica basada en las leyes de la excitabilidad nerviosa, que denomina dinámica cerebral. En el presente trabajo se expone de forma cronológica cómo surgen las principales ideas sobre las que se articula.Desarrollo: En 1939 Gonzalo observa los denominados fenómenos de acción dinámica: desfasamiento, facilitación y repercusión cerebral. Le siguen dos principios: efecto cerebral de la lesión según la magnitud y posición (1941), y organización sensorial, según un desarrollo espiral (1947). Paralelamente, caracteriza lo que llama el síndrome central de la corteza cerebral. En la década de los cincuenta desarrolla los conceptos de gradiente cortical, similitud y alometría. En contraposición a las concepciones modulares de la corteza cerebral, en las que una región es responsable de una función, Gonzalo expresa que ‘los gradientes corticales dan la localización de los sistemas mientras la similitud y alometría revelan su trama funcional’.Conclusiones: La teoría de dinámica cerebral se articula en dos etapas. La primera (de 1938 a 1950) se caracteriza por una importante base clínica con observación de nuevos fenómenos y formulación de nuevos conceptos. La segunda (de 1950 a 1960) incluye la introducción de conceptos de mayor alcance, como el gradiente funcional cortical, y leyes de alometría que se basan en un cambio de escala. Actualmente, varios autores consideran que el concepto de gradiente es clave para entender la organización cerebral.(AU)

Introduction: The Spanish neuroscientist Justo Gonzalo y Rodríguez-Leal (1910-1986) investigated the functional organisation of the cerebral cortex over more than four decades. His findings led him to formulate a neurophysiological theory based on the laws of nervous excitability, which he called brain dynamics. This paper presents in chronological order how the main ideas on which it is based arose.Development: In 1939, Gonzalo observed the phenomena of dynamic action: asynchrony or disaggregation, facilitation and cerebral repercussion. This was followed by two principles: the cerebral effect of lesions according to their magnitude and position (1941), and spiral development of the sensory field (1947). At the same time, he characterised what he called the central syndrome of the cerebral cortex. In the 1950s he developed the concepts of the cortical gradient, similarity and allometry. In contrast to modular conceptions of the cerebral cortex, in which one region is responsible for one function, Gonzalo argued that ‘cortical gradients provide the location of systems, while similarity and allometry reveal their functional mechanism.’Conclusions: The theory of brain dynamics was established in two stages. The first (between 1938 and 1950) had an important clinical foundation, involving the observation of new phenomena and the formulation of new concepts. The second (between 1950 and 1960) included the introduction of more far-reaching concepts, such as the functional cortical gradient, and allometry laws based on a change of scale. Today, various authors believe that the concept of the gradient is crucial for understanding how the brain is organised.(AU)

The effects of physical activity on white matter microstructure in children with overweight or obesity: The ActiveBrains randomized clinical trial / Los efectos de la actividad física sobre la microestructura de la sustancia blanca en niños con sobrepeso u obesidad: el ensayo clínico aleatorizado ActiveBrains

Background: Emerging research supports the idea that physical activity benefits brain development. However, the body of evidence focused on understanding the effects of physical activity on white matter microstructure during childhood is still in its infancy, and further well-designed randomized clinical trials are needed. Aim: This study aimed: (i) to investigate the effects of a 20-week physical activity intervention on global white matter microstructure in children with overweight or obesity, and (ii) to explore whether the effect of physical activity on white matter microstructure is global or restricted to a particular set of white matter bundles. Methods: In total, 109 children aged 8 to 11 years with overweight or obesity were randomized and allocated to either the physical activity program or the control group. Data were collected from November 2014 to June 2016, with diffusion tensor imaging (DTI) data processing and analyses conducted between June 2017 and November 2021. Images were pre-processed using the Functional Magnetic Resonance Imaging (MRI) of the Brain´s Software Library (FSL) and white matter properties were explored by probabilistic fiber tractography and tract-based spatial statistics (TBSS). Results: Intention-to-treat analyses were performed for all children who completed the pre-test and post-test DTI assessment, with good quality DTI data (N = 89). Of them, 83 children (10.06±1.11 years, 39 % girls, intervention group=44) met the per-protocol criteria (attended at least 70 % of the recommended sessions). Our probabilistic fiber tractography analysis did not show any effects in terms of global and tract-specific fractional anisotropy (FA) and mean diffusivity (MD) in the per-protocol or intention-to-treat analyses. Additionally, we did not observe any effects on the voxel-wise DTI parameters (i.e., FA and MD) using the most restricted TBSS approach (i.e., per protocol analyses and p-corrected image with a statistical...(AU)

Default mode network connectivity and social dysfunction in children with Attention Deficit/Hyperactivity Disorder

Objective: Attention Deficit/Hyperactivity Disorder (ADHD) negatively affects social functioning; however, its neurological underpinnings remain unclear. Altered Default Mode Network (DMN) connectivity may contribute to social dysfunction in ADHD. We investigated whether DMN's dynamic functional connectivity (dFC) alterations were associated with social dysfunction in individuals with ADHD. Methods: Resting-state fMRI was used to examine DMN subsystems (dorsal medial prefrontal cortex (dMPFC), medial temporal lobe (MTL)) and the midline core in 40 male ADHD patients (7-10 years) and 45 healthy controls (HCs). Connectivity correlations with symptoms and demographic data were assessed. Group-based analyses compared rsFC between groups with two-sample t-tests and post-hoc analyses. Results: Social dysfunction in ADHD patients was related to reduced DMN connectivity, specifically in the MTL subsystem and the midline core. ADHD patients showed decreased dFC between parahippocampal cortex (PHC) and left superior frontal gyrus, and between ventral medial prefrontal cortex (vMPFC) and right middle frontal gyrus compared to HCs (MTL subsystem). Additionally, decreased dFC between posterior cingulate cortex (PCC), anterior medial prefrontal cortex (aMPFC), and right angular gyrus (midline core) was observed in ADHD patients relative to HCs. No abnormal connectivity was found within the dMPFC. Conclusion: Preliminary findings suggest that DMN connectional abnormalities may contribute to social dysfunction in ADHD, providing insights into the disorder's neurobiology and pathophysiology. (AU)

The role of mindfulness on theta inter-brain synchrony during cooperation feedback processing: An EEG-based hyperscanning study

Mindfulness appears to improve empathy and understanding in relationships, which are necessary for successful cooperation. However, the impact of mindfulness on cooperation has not been fully studied. This study used hyperscanning technique to examine the effect of mindfulness on the inter-brain synchrony of interacting individuals during the cooperative tasks. Forty-one dyads were randomly assigned to a mindfulness group or a non-mindfulness group. Dyads of the mindfulness group performed a short mindfulness exercise following a 15-minute mindfulness audio guidance. Dyads of the non-mindfulness group were instructed to rest quietly with their eyes closed. Then, simultaneously and continuously EEG was recorded from all dyads when they completed a computer-based cooperative game task. Reaction times (RTs) and success rates were used to indicate the behavioral performance, and phase locking value (PLV) was used to indicate the inter-brain synchrony. The results showed that (1) Greater theta inter-brain synchrony during the cooperative computer game tasks was observed in the mindfulness group than in the non-mindfulness group; (2) Greater theta inter-brain synchrony was observed in the successful cooperation conditions as compared to those in the failure cooperation conditions; (3) Greater theta inter-brain synchrony was observed at the frontal region as compared to those at the parietal-occipital region in the successful cooperation condition. The results expand the neural basis of the effects of mindfulness on cooperation feedback processing. (AU)

Hypoconnectivity networks in schizophrenia patients: A voxel-wise meta-analysis of Rs-fMRI

In recent years several meta-analyses regarding resting-state functional connectivity in patients with schizophrenia have been published. The authors have used different data analysis techniques: regional homogeneity, seed-based data analysis, independent component analysis, and amplitude of low frequencies. Hence, we aim to perform a meta-analysis to identify connectivity networks with different activation patterns between people diagnosed with schizophrenia and healthy controls using voxel-wise analysis. Method: We collected primary studies exploring whole brain connectivity by functional magnetic resonance imaging at rest in patients with schizophrenia compared with healthy controls. We identified 25 studies included high-quality studies that included 1285 patients with schizophrenia and 1279 healthy controls. Results: The results indicate hypoactivation in the right precentral gyrus and the left superior temporal gyrus of patients with schizophrenia compared with healthy controls. Conclusions: These regions have been linked with some clinical symptoms usually present in Plea with schizophrenia, such as auditory verbal hallucinations, formal thought disorder, and the comprehension and production of gestures. (AU)

Childhood trauma is linked to abnormal static-dynamic brain topology in adolescents with major depressive disorder

Childhood trauma is a leading risk factor for adolescents developing major depressive disorder (MDD); however, the underlying neuroimaging mechanisms remain unclear. This study aimed to investigate the association among childhood trauma, MDD and brain dysfunctions by combining static and dynamic brain network models. We recruited 46 first-episode drug-naïve adolescent MDD patients with childhood trauma (MDD-CT), 53 MDD patients without childhood trauma (MDD-nCT), and 90 healthy controls (HCs) for resting-state functional magnetic resonance imaging (fMRI) scans; all participants were aged 13–18 years. Compared to the HCs and MDD-nCT groups, the MDD-CT group exhibited significantly higher global and local efficiency in static brain networks and significantly higher temporal correlation coefficients in dynamic brain network models at the whole-brain level, and altered the local efficiency of default mode network (DMN) and temporal correlation coefficients of DMN, salience (SAN), and attention (ATN) networks at the local perspective. Correlation analysis indicated that altered brain network features and clinical symptoms, childhood trauma, and particularly emotional neglect were highly correlated in adolescents with MDD. This study may provide new evidence for the dysconnectivity hypothesis regarding the associations between childhood trauma and MDD in adolescents from the perspectives of both static and dynamic brain topology. (AU)

Dimensional emotions are represented by distinct topographical brain networks

The ability to recognize others’ facial emotions has become increasingly important after the COVID-19 pandemic, which causes stressful situations in emotion regulation. Considering the importance of emotion in maintaining a social life, emotion knowledge to perceive and label emotions of oneself and others requires an understanding of affective dimensions, such as emotional valence and emotional arousal. However, limited information is available about whether the behavioral representation of affective dimensions is similar to their neural representation. To explore the relationship between the brain and behavior in the representational geometries of affective dimensions, we constructed a behavioral paradigm in which emotional faces were categorized into geometric spaces along the valence, arousal, and valence and arousal dimensions. Moreover, we compared such representations to neural representations of the faces acquired by functional magnetic resonance imaging. We found that affective dimensions were similarly represented in the behavior and brain. Specifically, behavioral and neural representations of valence were less similar to those of arousal. We also found that valence was represented in the dorsolateral prefrontal cortex, frontal eye fields, precuneus, and early visual cortex, whereas arousal was represented in the cingulate gyrus, middle frontal gyrus, orbitofrontal cortex, fusiform gyrus, and early visual cortex. In conclusion, the current study suggests that dimensional emotions are similarly represented in the behavior and brain and are presented with differential topographical organizations in the brain. (AU)

Mind matters: A narrative review on affective state-dependency in non-invasive brain stimulation

Variability in findings related to non-invasive brain stimulation (NIBS) have increasingly been described as a result of differences in neurophysiological state. Additionally, there is some evidence suggesting that individual differences in psychological states may correlate with the magnitude and directionality of effects of NIBS on the neural and behavioural level. In this narrative review, it is proposed that the assessment of baseline affective states can quantify non-reductive properties which are not readily accessible to neuroscientific methods. Particularly, affective-related states are theorized to correlate with physiological, behavioural and phenomenological effects of NIBS. While further systematic research is needed, baseline psychological states are suggested to provide a complementary cost-effective source of information for understanding variability in NIBS outcomes. Implementing measures of psychological state may potentially contribute to increasing the sensitivity and specificity of results in experimental and clinical NIBS studies. (AU)

Evidence-based umbrella review of non-invasive brain stimulation in anxiety disorders

Background and objectives Although several meta-analyses have suggested the efficacy of non-invasive brain stimulation (NIBS) mainly in prefrontal brain areas to treat mental disorders, no synthetic approach has been performed for other psychiatric disorders rather than depression. The objective is to assess the available evidence of NIBS in the treatment of anxiety disorders. Methods An umbrella review (CRD42021239577) was performed only looking for reviews with meta-analyses of randomized clinical trials using a source strategy MeSH keywords in MEDLINE through Pubmed by two independent researchers. The effects of different methods of NIBS in anxiety disorders were assessed using the PICO strategy. The methodological quality was evaluated using AMSTAR-2 and certainty of evidence using the GRADE-pro framework. Results From 136 screening meta-analyses, 16 from 14 studies were included in the final analysis. Generalized Anxiety Disorder (GAD) and Obsessive Compulsive Disorder (OCD) respond best to low frequency repetitive transcranial magnetic stimulation (rTMS), while Posttraumatic Stress Disorder (PTSD) has the largest effect size at high frequency rTMS. Panic Disorder (PD) has no evidence for clinical use of NIBS. There were not identified meta-analyses about other anxiety disorders. In general, the included studies had good methodological quality, but low to moderate evidence for clinical recommendation. Conclusion Available evidence reveals NIBS as an effective and safe approach to treat GAD, PTSD and OCD with low recommendation level to clinical application. A great heterogeneity of studies indicates the necessity to develop new randomized clinical trials applying NIBS to treat those and other mental disorders. (AU)

Ghrelin prevents lethality in a rat endotoxemic model through central effects on the vagal pathway and adenosine A2B signaling

Accumulating evidence suggest that ghrelin plays a role as an antiseptic peptide. The present study aimed to clarify whether the brain may be implicated ghrelin’s antiseptic action. We examined the effect of brain ghrelin on survival in a novel endotoxemic model achieved by treating rats with lipopolysaccharide (LPS) and colchicine. The observation of survival stopped three days after chemicals’ injection or at death. Intracisternal ghrelin dose-dependently reduced lethality in the endotoxemic model; meanwhile, neither intraperitoneal injection of ghrelin nor intracisternal des-acyl-ghrelin injection affected the mortality rate. The brain ghrelin-induced lethality reduction was significantly blocked by surgical vagotomy. Moreover, intracisternal injection of a ghrelin receptor antagonist blocked the improved survival achieved by intracisternal ghrelin injection or intravenous 2-deoxy-d-glucose administration. Intracisternal injection of an adenosine A2B receptor agonist reduced the lethality and the ghrelin-induced improvement of survival was blocked by adenosine A2B receptor antagonist. I addition, intracisternal ghrelin significantly blocked the colonic hyperpermeability produced by LPS and colchicine. These results suggest that ghrelin acts centrally to reduce endotoxemic lethality. Accordingly, activation of the vagal pathway and adenosine A2B receptors in the brain may be implicated in the ghrelin-induced increased survival. Since the efferent vagus nerve mediates anti-inflammatory mechanisms, we speculate that the vagal cholinergic anti-inflammatory pathway is implicated in the decreased septic lethality caused by brain ghrelin. (AU)

Clinical Utility of Automated Structural Brain Volume Analysis in MRI for Evaluating Temporal Lobe Epilepsy in Fitness Athletes

Background: Investigating alterations in brain volumes among individuals with magnetic resonance-negative temporal lobe epilepsy (MRIn-MTLE) is of particular interest in the context of athletes and fitness enthusiasts. In this study, we aimed to examine these brain volume changes and their potential implications. Methods: We conducted a retrospective analysis of T1-weighted brain images from MRIn-MTLE patients and healthy controls (HC) who were actively engaged in athletics or fitness activities. Brain regions were segmented and quantified using FreeSurfer software, and we compared the volumes of ipsilateral brain regions between patients and controls. We employed Feature Explorer software, based on Pyradiomics, to construct a classification model using volume parameters and assessed its effectiveness in distinguishing between MRIn-MTLE patients and controls. Results: Significant differences in brain volumes were observed in various regions of the brain, both on the left and right sides, among both HC and MRIn-MTLE patients. Notably, these differences varied by gender. In males, the estimated total intracranial volume (eTIV) and the volumes of specific regions in the left hemisphere were larger in the HC group than in the MRIn-MTLE group. In females, certain brain regions in the right hemisphere were smaller in MRIn-MTLE patients compared to the HC group. The classification model achieved an area under the curve (AUC) of 0.780 and an accuracy of 0.721. Conclusions: Our study identified notable reductions in brain volumes among MRIn-MTLE patients who are athletes or fitness enthusiasts. Further investigations are needed to understand the underlying physiological and anatomical factors contributing to these differences. The findings suggest that brain volume measurements can serve as valuable features for constructing classification models to differentiate MRIn-MTLE patients from healthy individuals in the athletic and fitness community. (AU)

Redescubriendo al paciente M: Justo Gonzalo Rodríguez-Leal y su teoría de la dinámica cerebral / Rediscovering patient M: Justo Gonzalo Rodríguez-Leal and his theory of the brain dynamics

Introducción: En el transcurso de la Guerra Civil española, Justo Gonzalo Rodríguez-Leal visita al paciente M en el Hospital de Sanidad Militar de Godella (Valencia). Este encuentro marca el inicio de una larga relación entre ambos, que brinda a Justo Gonzalo la oportunidad de estudiar la organización funcional cerebral y articular una original concepción de la neurofisiología basada en las leyes de la excitabilidad nerviosa. El objetivo de este trabajo es redescubrir al paciente M y la interpretación fisiológica de la dinámica cerebral de Gonzalo.Desarrollo: Tomando como piedra angular al paciente M, Gonzalo postula que el efecto de una lesión cortical depende de su magnitud y posición: la magnitud condiciona la intensidad del trastorno; la posición, el tipo de trastorno. Entre 1945 y 1950 desarrolla en profundidad estas y otras hipótesis, basadas en observaciones clínicas, en la obra Dinámica cerebral, La actividad cerebral en función de las condiciones dinámicas de la excitabilidad nerviosa (Vol. 1, 1945; Vol. 2, 1950). A partir de 1952 proporciona una versión ampliada de su teoría sobre dinámica cerebral, fundamentándola no sólo en conceptos fisiológicos, sino también en la idea de gradientes cerebrales, e introduciendo los conceptos de similitud y alometría de los sistemas dinámicos.Conclusiones: Durante siglos, el conocimiento sobre la organización funcional del cerebro se ha asentado en el estudio de casos únicos. El paciente M constituye un ejemplo más de esta tradición, ayudando a establecer las bases de la teoría de dinámica cerebral desarrollada por Justo Gonzalo.(AU)

Introduction: During the Spanish Civil War, Justo Gonzalo Rodríguez-Leal visited patient M at the Military Healthcare Hospital in Godella (Valencia). This meeting marked the beginning of a long relationship between the two, which gave Justo Gonzalo the opportunity to study the functional organisation of the brain and to develop an original conception of neurophysiology based on the laws of nervous excitability. The aim of this work is to rediscover patient M and the physiological interpretation of Gonzalo’s brain dynamics.Development: Taking patient M as the cornerstone, Gonzalo postulated that the effect of a cortical lesion depends on its magnitude and position: the magnitude conditions the intensity of the disorder, whereas the position determines the type of disorder. Between 1945 and 1950 he developed these and other hypotheses in depth, based on clinical observations, in his work Dinámica cerebral. La actividad cerebral en función de las condiciones dinámicas de la excitabilidad nerviosa (Vol. 1, 1945; Vol. 2, 1950). From 1952 onwards he provided an expanded version of his theory of brain dynamics, basing it not only on physiological concepts, but also on the idea of brain gradients, and introducing the concepts of similarity and allometry of dynamic systems.Conclusions: For centuries, knowledge about the functional organisation of the brain has been based on single case studies. Patient M is a further example of this tradition that helps to establish the basis of the theory of brain dynamics developed by Justo Gonzalo.(AU)

Realidad y ficción en neurociencias. Prevalencia de neuromitos entre docentes universitarios de ciencias de la salud / Fact and fiction in neuroscience. Prevalence of neuromyths among university professors of health sciences

Introducción: Desde la década de los noventa, muchos docentes han mostrado un creciente interés por las neurociencias y por la pronta aplicación de los hallazgos neurocientíficos a la educación en al aula, lo cual ha acarreado la proliferación de numerosos neuromitos. Objetivo: Evaluar la prevalencia de neuromitos y el conocimiento sobre el funcionamiento del cerebro entre participantes en un programa de perfeccionamiento en educación en ciencias de la salud, todos ellos profesionales de la salud y profesores universitarios. Sujetos y métodos: El 88% de un total de 197 participantes de cuatro cohortes respondió un cuestionario en línea con 21 afirmaciones acerca del funcionamiento del cerebro, entre las cuales había algunos neuromitos. Se realizó un análisis de frecuencias para cada respuesta obtenida en las diferentes cohortes involucradas en el estudio y una comparación en la muestra general utilizando la prueba de chi cuadrado. Resultados: El 76,6% de los participantes respondió correctamente la mayoría de las afirmaciones sobre el conocimiento de la función cerebral y fue capaz de reconocer algunos de los neuromitos planteados. Cuatro aseveraciones (tres neuromitos y una acerca del funcionamiento cerebral) tuvieron un rendimiento por debajo del 50% (29,2%). Éstas fueron respondidas de forma incorrecta por el 56,3%, y alrededor del 15% de los participantes declaró no saber la respuesta correcta; incluso en dos de ellas el desconocimiento superó el 20%. Conclusiones: Un adecuado conocimiento sobre el funcionamiento del cerebro por parte de los profesores puede permitirles reconocer algunos neuromitos que podrían afectar de manera negativa a su práctica pedagógica, influenciando su desempeño y resultados académicos.(AU)

Introduction: Since the 1990s, many teachers have had a growing interest in neuroscience and in the early application of neuroscientific findings to education in the classroom, which has led to the proliferation of numerous neuromyths. Objective: To assess the prevalence of neuromyths and knowledge about the functioning of the brain among participants in an improvement program in Health Sciences Education, all of them health professionals and university professors. Subjects and methods: 88% of a total of 197 participants from four cohorts answered an online questionnaire with 21 sentences about the functioning of the brain, including some neuromyths. A frequency analysis was performed for each response obtained in the different cohorts involved in the study and a comparison in the general sample using the chi-square test. Results: 76.6% of the participants answered most of the statements about knowledge of brain function correctly and were able to recognize some of the neuromyths posed. Four statements (three neuromyths and one about brain function) had a performance below 50% (29.2%). These were answered incorrectly by 56.3%, and around 15% of the participants stated that they did not know the correct answer, even in two of them the ignorance exceeded 20%. Conclusions: An adequate knowledge of the functioning of the brain by teachers can allow them to recognize some neuromyths that could negatively affect their pedagogical practice, influencing their performance and academic results.(AU)

Abnormal degree centrality and functional connectivity in Down syndrome: A resting-state fMRI study

Background/Objective: Neuroimaging studies have shown brain abnormalities in Down syndrome (DS) but have not clarified the underlying mechanisms of dysfunction. Here, we investigated the degree centrality (DC) abnormalities found in the DS group compared with the control group, and we conducted seed-based functional connectivity (FC) with the significant clusters found in DC. Moreover, we used the significant clusters of DC and the seed-based FC to elucidate differences between brain networks in DS compared with controls.Method: The sample comprised 18 persons with DS (M = 28.67, SD = 4.18) and 18 controls (M = 28.56, SD = 4.26). Both samples underwent resting-state functional magnetic resonance imaging. Results: DC analysis showed increased DC in the DS in temporal and right frontal lobe, as well as in the left caudate and rectus and decreased DC in the DS in regions of the left frontal lobe. Regarding seed-based FC, DS showed increased and decreased FC. Significant differences were also found between networks using Yeo parcellations, showing both hyperconnectivity and hypoconnectivity between and within networks. Conclusions: DC, seed-based FC and brain networks seem altered in DS, finding hypo- and hyperconnectivity depending on the areas. Network analysis revealed between- and within-network differences, and these abnormalities shown in DS could be related to the characteristics of the population. (AU)

Anorexia nerviosa, microbiota y cerebro

La anorexia nerviosa (AN) es una enfermedad psiquiátrica, con elevada prevalencia y comorbilidades, caracterizada por una baja tasa de respuestaal tratamiento. Se considera una enfermedad multifactorial. En los últimos años se ha puesto el foco en la presencia de disbiosis intestinal ysu posible implicación como factor causal, así como alternativa de tratamiento. El objetivo de este trabajo ha sido revisar el estado actual delconocimiento de las alteraciones en la microbiota intestinal identificadas en pacientes con AN y la posibilidad del uso de probióticos como alternativa terapéutica. Se han descrito importantes cambios en la diversidad de las especies asociadas a la pérdida de peso que podrían contribuira perpetuar el trastorno y que explicarían muchas de las alteraciones nutricionales, gastrointestinales, psicológicas y cognitivas presentes enestos pacientes. El uso de probióticos, poco estudiado aún en pacientes con AN, abre una nueva ventana para mejorar la respuesta, siempre dela mano de los tratamientos convencionales. (AU)

Anorexia nervosa (AN) is a psychiatric disease with a high prevalence and comorbidities, characterized by a low response rate to treatment.It is considered as a multifactorial disease. In recent years, the focus has been placed on the presence of intestinal dysbiosis and its possibleinvolvement as a causal factor as well as an alternative treatment. The objective of this work has been to review the current state of knowledge ofalterations in the intestinal microbiota identified in patients with AN and the possibility of using probiotics as a therapeutic alternative. Significantchanges in the diversity of species associated with weight loss have been described that could favor the perpetuation of the disorder, and that wouldexplain many of the nutritional, gastrointestinal, psychological, and cognitive alterations present in these patients. The use of probiotics, still littlestudied in patients with AN, sheds some light on this matter to improve the treatment response, always hand in hand with conventional treatments. (AU)