Los misterios del cerebro en Infobae: ¿para qué dormimos?

16/06. Infobae. Link nota completa: goo.gl/SHUdPR Durante el descanso ocurren procesos fundamentales para el organismo. Está asociado con funciones inmunológicas, endócrinas y de la memoria. El prestigioso neurocientífico argentino Facundo Manes explica la importancia del sueño para la buena salud en #CerebrosenRed

Barttfeld P, Petroni A, Báez S, Urquina H, Sigman M, Cetkovich M, Torralva T, Torrente F, Lischinsky A, Castellanos FX,Manes F, Ibanez A.  Functional Connectivity and Temporal Variability of Brain Connections in Adults with ADHD and Bipolar Disorder. Neuropyschobiology 2014

Objectives: To assess brain functional connectivity and variability in adults with attention deficit/hyperactivity disorder (ADHD) or euthymic bipolar disorder (BD) relative to a control (CT) group.

Methods: Electroencephalography (EEG) was measured in 35 participants (BD = 11; ADHD = 9; CT = 15) during an eyes-closed 10-min rest period, and connectivity and graph theory metrics were computed. A coefficient of variation (CV) computed also the connectivity’s temporal variability of EEG. Multivariate associations between functional connectivity and clinical and neuropsychological profiles were evaluated.

Results: An enhancement of functional connectivity was observed in the ADHD (fronto-occipital connections) and BD (diffuse connections) groups. However, compared with CTs, intrinsic variability (CV) was enhanced in the ADHD group and reduced in the BD group. Graph theory metrics confirmed the existence of several abnormal network features in both affected groups. Significant associations of connectivity with symptoms were also observed. In the ADHD group, temporal variability of functional connections was associated with executive function and memory deficits. Depression, hyperactivity and impulsivity levels in the ADHD group were associated with abnormal intrinsic connectivity. In the BD group, levels of anxiety and depression were related to abnormal frontotemporal connectivity.

Conclusions: In the ADHD group, we found that intrinsic variability was associated with deficits in cognitive performance and that connectivity abnormalities were related to ADHD symptomatology. The BD group exhibited less intrinsic variability and more diffuse long-range brain connections, and those abnormalities were related to interindividual differences in depression and anxiety. These preliminary results are relevant for neurocognitive models of abnormal brain connectivity in both disorders.

Couto JB, Salles A, Sedeño L, Paradejordi M, Barttfeld P, Canales-Johnson AF, Dos Santos, YV., Huepe D,Bekinschtein T, Sigman M, Favaloro RR, Favaloro R, Manes F, Ibanez A.  The man who feels two hearts: The different pathways of interoception. Social Cognitive and Affective Neurosciences 2014 10.3389/fnagi.2014.00262

Recent advances in neuroscience have provided new insights into the understanding of heart-brain interaction and communication. Cardiac information to the brain relies on two pathways, terminating in the insular (IC) and anterior cingulate (ACC) cortices, along with the somatosensory cortex (S1-S2). Interoception relying on these neuroanatomical pathways has been shown to modulate social cognition. We report the case study of C.S., a patient with an «external heart » (an extracorporeal left-univentricular cardiac assist device, LVAD). The patient was assessed with neural/behavioral measures of cardiac interoception complemented by neuropsychological and social cognition measures. The patient’s performance on the interoception task (heartbeat detection) seemed to be guided by signals from the artificial LVAD, which provides a somatosensory beat, rather than by his endogenous heart. Cortical activity (heart-evoked potential, HEP) decreased in comparison to normal volunteers, particularly during interoceptive states. The patient accurately performed several cognitive tasks, expect for empathy, theory of mind and decision-making. This evidence suggests an imbalance in the patient’s cardiac interoceptive pathways that enhances sensation driven by the artificial pump over that from the cardiac vagal-ICC-ACC pathway. A patient with two hearts, one endogenous and one artificial, presents a unique opportunity to explore models of interoception and heart-brain interaction

Falquez R, Couto JB, Ibanez A, Freitag MT, Berger M, Arens E, Lang S, Barnow S.  Detaching from the negative by reappraisal: the role of right superior frontal gyrus (BA9/32). Frontiers in Behavioral Neuroscience 2014

The ability to reappraise the emotional impact of events is related to long-term mental health. Self-focused reappraisal (REAPPself), i.e., reducing the personal relevance of the negative events, has been previously associated with neural activity in regions near right medial prefrontal cortex, but rarely investigated among brain-damaged individuals. Thus, we aimed to examine the REAPPself ability of brain-damaged patients and healthy controls considering structural atrophies and gray matter intensities, respectively. Twenty patients with well-defined cortex lesions due to an acquired circumscribed tumor or cyst and 23 healthy controls performed a REAPPself task, in which they had to either observe negative stimuli or decrease emotional responding by REAPPself. Next, they rated the impact of negative arousal and valence. REAPPself ability scores were calculated by subtracting the negative picture ratings after applying REAPPself from the ratings of the observing condition. The scores of the patients were included in a voxel-based lesion-symptom mapping (VLSM) analysis to identify deficit related areas (ROI). Then, a ROI group-wise comparison was performed. Additionally, a whole-brain voxel-based-morphometry (VBM) analysis was run, in which healthy participant’s REAPPself ability scores were correlated with gray matter intensities. Results showed that (1) regions in the right superior frontal gyrus (SFG), comprising the right dorsolateral prefrontal cortex (BA9) and the right dorsal anterior cingulate cortex (BA32), were associated with patient’s impaired down-regulation of arousal, (2) a lesion in the depicted ROI occasioned significant REAPPself impairments, (3) REAPPself ability of controls was linked with increased gray matter intensities in the ROI regions. Our findings show for the first time that the neural integrity and the structural volume of right SFG regions (BA9/32) might be indispensable for REAPPself. Implications for neurofeedback research are discussed.

Escobar J, Huepe D, Decety J, Sedeño L, Messow MC, Báez S, Rivera-Rei A, Canales-Johnson AF, Morales JP, Johannes Schroeder, Manes F, Lopez V, Ibanez A.  Brain signatures of moral sensitivity in adolescents with early social deprivation. Scientific Reports 2014

The present study examined neural responses associated with moral sensitivity in adolescents with a background of early social deprivation. Using high-density electroencephalography (hdEEG), brain activity was measured during an intentional inference task, which assesses rapid moral decision-making regarding intentional or unintentional harm to people and objects. We compared the responses to this task in a socially deprived group (DG) with that of a control group (CG). The event-related potentials (ERPs) results showed atypical early and late frontal cortical markers associated with attribution of intentionality during moral decision-making in DG (especially regarding intentional harm to people). The source space of the hdEEG showed reduced activity for DG compared with CG in the right prefrontal cortex, bilaterally in the ventromedial prefrontal cortex (vmPFC), and right insula. Moreover, the reduced response in vmPFC for DG was predicted by higher rates of externalizing problems. These findings demonstrate the importance of the social environment in early moral development, supporting a prefrontal maturation model of social deprivation.

Lanfranco R, Adolfi F, Ibanez A. Hypnotic suggestion: A test for the voluntary action problem. Cognitive Neuroscience 2014

To study voluntary action a dissociation must be established between the somatic event (e.g., motor action) and what the agent voluntarily does (e.g., handing a tool to a friend). We propose that cognitive neuroscience studies of hypnotic suggestion can accomplish this dissociation between action and will (more specifically, between action and intention, or action and volition). Thus, hypnotic suggestion may afford an empirical testing ground to study voluntary action, distinguishing voluntariness from action.

Lichtensztejn M., Macchi P, Lischinsky A. Music Therapy and Disorders of Consciousness: Providing Clinical Data for Differential Diagnosis between Vegetative State and Minimally Conscious State from Music-Centered Music Therapy and Neuroscience Perspectives. Music Therapy Perspectives 2014

Music Therapy and Disorders of Consciousness: Providing Clinical Data for Differential Diagnosis between Vegetative State and Minimally Conscious State from Music-Centered Music Therapy and Neuroscience Perspectives. Autores Lichtensztejn M., Macchi P, Lischinsky A. Año 2014 Journal  Lichtensztejn M., Macchi P, Lischinsky A. Volumen Abstract   Otra información    

Sinay V, Manuel Perez Akly, Gisela Zanga, Celina Ciardi, Racosta J. School performance as a marker of cognitive decline prior to diagnosis of multiple sclerosis. Mult Scler. 2015

Durante muchos años, el deterioro cognitivo se ha establecido como un síntoma bien conocido de la esclerosis múltiple. Además, sabemos que está presente incluso al principio de la enfermedad. En este estudio de casos y controles, decidimos evaluar si hay un deterioro de las funciones cognitivas, incluso antes de la aparición en aquellos pacientes que eventualmente sufren de esclerosis múltiple. Se evaluó el desempeño de la escuela en general, y en particular el rendimiento escolar en matemáticas y lenguaje en un grupo de pacientes que más tarde desarrollarían la enfermedad y comparamos nuestros resultados con un grupo control. Se encontró que el rendimiento escolar era más pobre en los sujetos que iban a sufrir esclerosis múltiple. Paralelamente, encontramos que cuanto más tardío fuera el comienzo del primer síntoma, mejor eran las calificaciones. La prueba de un déficit cognitivo premórbido por un método de evaluación indirecta validado nos permitió comprobar la existencia de un compromiso neurológico, incluso antes de un diagnóstico clínico o la realización de la primera resonancia magnética en pacientes que luego sufrirían de esclerosis múltiple.