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Cortical single neuron activity and local field potential patterns change at different depths of general anesthesia. Here, we investigate the associated network level changes of functional connectivity. We recorded ongoing electrocorticographic (ECoG) activity from temporo-parieto-occipital cortex of 6 ferrets at various levels of isoflurane/nitrous oxide anesthesia and determined functional connectivity by computing amplitude envelope correlations. Through hierarchical clustering, we derived typical connectivity patterns corresponding to light, intermediate and deep anesthesia. Generally, amplitude correlation strength increased strongly with depth of anesthesia across all cortical areas and frequency bands. This was accompanied, at the deepest level, by the emergence of burst-suppression activity in the ECoG signal and a change of the spectrum of the amplitude envelope. Normalization of functional connectivity to the distribution of correlation coefficients showed that the topographical patterns remained similar across depths of anesthesia, reflecting the functional association of the underlying cortical areas. Thus, while strength and temporal properties of amplitude co-modulation vary depending on the activity of local neural circuits, their network-level interaction pattern is presumably most strongly determined by the underlying structural connectivity.

Complex and variable behavior requires fast changes of functional connectivity in large-scale cortical networks. Here, we report on the cortical dynamics of functional coupling across visual, auditory and parietal areas during a lateralized detection task in the ferret. We hypothesized that fluctuations in coupling, indicative of dynamic variations in the network state, might predict the animals’ performance. While power for hit and miss trials showed significant differences only around stimulus and response onset, phase coupling already differed before stimulus onset. Principal component analysis of directed coupling at the single-trial level during this period revealed subnetworks that most strongly related to behavior. While higher global phase coupling of visual and auditory regions to parietal cortex was predictive of task performance, a second component showed that a reduction in coupling between subnetworks of sensory modalities was also necessary, probably to allow a better detection of the unimodal signals. Furthermore, we observed that long-range coupling became more predominant during the task period compared to the pre-stimulus baseline. Taken together, these results suggest that fluctuations in the network state, particular with respect to long-range connectivity, are key determinants of the animals’ behavior.

Audiovisual integration is facilitated by the context-specific dynamical reconfiguration of cortical intrinsic coupling., Intrinsically generated patterns of coupled neuronal activity are associated with the dynamics of specific brain states. Sensory inputs are extrinsic factors that can perturb these intrinsic coupling modes, creating a complex scenario in which forthcoming stimuli are processed. Studying this intrinsic-extrinsic interplay is necessary to better understand perceptual integration and selection. Here, we show that this interplay leads to a reconfiguration of functional cortical connectivity that acts as a mechanism to facilitate stimulus processing. Using audiovisual stimulation in anesthetized ferrets, we found that this reconfiguration of coupling modes is context specific, depending on long-term modulation by repetitive sensory inputs. These reconfigured coupling modes lead to changes in latencies and power of local field potential responses that support multisensory integration. Our study demonstrates that this interplay extends across multiple time scales and involves different types of intrinsic coupling. These results suggest a previously unknown large-scale mechanism that facilitates multisensory integration.

Intrinsic coupling modes (ICMs) provide a framework for describing the interactions of ongoing brain activity at multiple spatial and temporal scales. Two families of ICMs can be distinguished: phase and envelope ICMs. The principles that shape these ICMs remain partly elusive, in particular their relation to the underlying brain structure. Here we explored structure-function relationships in the ferret brain between ICMs quantified from ongoing brain activity recorded with chronically implanted ECoG arrays and structural connectivity (SC) obtained from high-resolution diffusion MRI tractography. Large-scale computational models as well as simple topological ingredients of SC were used to explore the ability to predict both types of ICMs. Importantly, all investigations were conducted with ICM measures that are sensitive or insensitive to volume conduction effects. The results show that both types of ICMs are strongly related to SC, except when using ICM measures removing zero-lag synchronizations. Computational models are challenged to predict these ICM patterns consistently, and simple predictions from SC topological features can sometimes outperform them. Overall, the results demonstrate that patterns of cortical functional coupling as reflected in both phase and envelope ICMs bear a substantial relation to the underlying structural connectivity of the cerebral cortex.

Synchronous spiking of multiple neurons is a key phenomenon in normal brain function and pathologies. Recently, approaches to record spikes from the intact cortical surface using small high-density arrays of microelectrodes have been reported. It remained unaddressed how epicortical spiking relates to intracortical unit activity. We introduce a mesoscale approach using an array of 64 electrodes with intermediate diameter (250 µm) and combined large-coverage epicortical recordings in ferrets with intracortical recordings via laminar probes. Empirical data and modeling strongly suggest that our epicortical electrodes selectively captured synchronized spiking of neurons in the subjacent cortex. As a result, responses to sensory stimulation were more robust and less noisy as compared to intracortical activity, and receptive field properties were well preserved in epicortical recordings. This should promote insights into assembly-coding beyond the informative value of subdural EEG or single-unit spiking, and be advantageous to real-time applications in brain-machine interfacing.Significance statementElectrocorticography allows chronic, low-noise recordings from the intact cortical surface - a prerequisite for investigations into brain network dynamics and brain-machine interfaces. Novel electrodes can capture spiking activity at the surface, which should boost precision in the spatial - and time domain, compared to conventional EEG-like measurements. To clarify how surface spiking relates to intracortically fired action potentials, we recorded both types of signal simultaneously from sensory cortices in anesthetized ferrets. Results suggest that mesoscale (250 µm) surface electrodes can selectively capture synchronized spiking from nearby cortical columns, which reduces contamination by non-representative, jittering spikes. Given the high relevance of neural synchrony for sensorimotor and cognitive processing, the novel methodology may improve signal decoding in brain-machine interface approaches.Author contributionsE.G.L., T.B. and A.K.E. conceptualized the research; E.G.L. and F.P. performed experiments; T.B. and E.G.L. wrote Matlab routines for data analysis; T.B. and E.G.L. analyzed the data; T.S. provided technical resources; T.B., E.G.L. and A.K.E. wrote the manuscript; G.E. administrated the project; A.K.E. acquired funding.

O objetivo principal deste artigo é apresentar os resultados obtidos na aplicação de procedimentos de treino baseados nas técnicas da Análise Comportamental Aplicada (ACA) a alunos na situação de insucesso escolar. Programas de treino anteriormente aplicados com sucesso a alunos do 1.º ao 3.º ano de escolaridade, foram aplicados nesta investigação a três alunos com problemas de insucesso escolar do 4.º ano de escolaridade.

In the superior colliculus (SC), visual afferent inputs from various sources converge in a highly organized way such that all layers form topographically aligned representations of contralateral external space. Despite this anatomical organization, it remains unclear how the layer-specific termination of different visual input pathways is reflected in the nature of visual response properties and their distribution across layers. To uncover the physiological correlates underlying the laminar organization of the SC, we recorded multiunit and local field potential activity simultaneously from all layers with dual-shank multichannel linear probes. We found that the location of spatial receptive fields was strongly conserved across all visual responsive layers. There was a tendency for receptive field size to increase with depth in the SC, with superficial receptive fields significantly smaller than deep receptive fields. Additionally, superficial layers responded significantly faster than deeper layers to flash stimulation. In some recordings, flash-evoked responses were characterized by the presence of gamma oscillatory activity (40–60 Hz) in multiunit and field potential signals, which was strongest in retinorecipient layers. While SC neurons tended to respond only weakly to full-field drifting gratings, we observed very similar oscillatory responses to the offset of grating stimuli, suggesting gamma oscillations are produced following light offset. Oscillatory spiking activity was highly correlated between horizontally distributed neurons within these layers, with oscillations temporally locked to the stimulus. Together, visual response properties provide physiological evidence reflecting the laminar-specific termination of visual afferent pathways in the SC, most notably characterized by the oscillatory entrainment of superficial neurons.

Throughout each day, the brain displays transient changes in state, as evidenced by shifts in behavior and vigilance. While the electrophysiological correlates of brain states have been studied for some time, it remains unclear how large-scale cortico-cortical functional connectivity systematically reconfigures across states. Here, we investigate state-dependent shifts in cortical functional connectivity by recording local field potentials (LFPs) during spontaneous behavioral transitions in the ferret using chronically implanted micro-electrocorticographic (µECoG) arrays positioned over occipital, parietal, and temporal cortical regions. To objectively classify brain state, we describe a data-driven approach that projects time-varying LFP spectral properties into brain state space. Distinct brain states displayed markedly different patterns of cross-frequency phase-amplitude coupling and inter-electrode phase synchronization across several LFP frequency bands. The largest across-state differences in functional connectivity were observed between periods of presumed slow-wave and rapid-eye-movement-sleep/active-state, which were characterized by the contrasting phenomena of cortical network fragmentation and global synchronization, respectively. Collectively, our data provide strong evidence that large-scale functional interactions in the brain dynamically reconfigure across behavioral states.

Este artículo es un análisis del lenguaje en la diplomacia y la política desde el punto de vista psicológico. Después de una introducción sobre la importancia el lenguaje en la diplomacia, se hace una delimitación del campo, siñalando que será tratado básicamente el lenguage oral, aunque algunas consideraciones son aplicables también al lenguaje escrito. No se pretende analizar la abundante bibliografía existente sobre el tema, sino las aplicaciones de la teoría de los actos del habla (TAH) en la práctica diplomática y política. Se hace un análisis de las maneras de proceder en un intercambio verbal en el que se maneja el lenguaje con objetivos precisos. Se explican las técnicas de reconocimiento de los signos de división social, uso de los pronombres personales para expresar "clusividad", estrategias de conciliación y ""escuchar activamente. Luego se abordan las estrategias de formulación y reformulación (framing y reframing) utilizadas para persuadir al oyente, así como también otras formas de formulación como las técnicas de sugestión y retórica. Se proporcionan numerosos ejemplos tomados de la historia diplomática e política reciente. La conclusión es que la psicología e la psicolingüistica pueden hacer una contribución importante no sólo para explicar las diferentes formas de expresión, sino para enseñar a dominarlas a fin de a resolver situaciones conflictivas.Palabras Clave: Psicología del lenguaje, teoría de los actos del habla, diplomacia, política internacional.

Vygotsky’s contribution as creator of a conception of abnormal development and founder of “Defectology” is explored in the paper. It includes an overview on the origins of the Cultural-Historical School (CHS) and its theory of psychological development. The CHS was born under the influence of Pavlov, Hegel, Marx, the Gestaltpsychologie and behaviourism. Its developmental theory is based on the concept of appropriation; there are two co-existing lines of development, a biological and a cultural-social line, which maintain a dialectical relationship. Some children have an impairment that provokes a divergence of these lines, causing a deficiency. It is therefore necessary to create links between these two lines, rebuilding the process of appropriation. The Vygotskian concept of deviated development is based on: the principle of social compensation, the concept of primary or secondary levels of defects, and the concept of structure of deviated development. Some of this model’s consequences for the diagnostic and treatment of persons with deficiencies are analysed.

Correlation of ongoing neural dynamics reveals the various carrier frequencies of cortico-tectal functional interaction., In the absence of sensory stimulation or motor output, the brain exhibits complex spatiotemporal patterns of intrinsically generated neural activity. Analysis of ongoing brain dynamics has identified the prevailing modes of cortico-cortical interaction; however, little is known about how such patterns of intrinsically generated activity are correlated between cortical and subcortical brain areas. We investigate the correlation structure of ongoing cortical and superior colliculus (SC) activity across multiple spatial and temporal scales. Ongoing cortico-tectal interaction was characterized by correlated fluctuations in the amplitude of delta, spindle, low gamma, and high-frequency oscillations (>100 Hz). Of these identified coupling modes, topographical patterns of high-frequency coupling were the most consistent with patterns of anatomical connectivity, reflecting synchronized spiking within cortico-tectal networks. Cortico-tectal coupling at high frequencies was temporally parcellated by the phase of slow cortical oscillations and was strongest for SC-cortex channel pairs that displayed overlapping visual spatial receptive fields. Despite displaying a high degree of spatial specificity, cortico-tectal coupling in lower-frequency bands did not match patterns of cortex-to-SC anatomical connectivity. Collectively, our findings demonstrate that neural activity is spontaneously coupled between cortex and SC, with high- and low-frequency modes of coupling reflecting direct and indirect cortico-tectal interactions, respectively.

O insucesso escolar, resultante de fatores ambientais e biológicos, ou de ambos, manifesta-se de várias maneiras e provoca um desvio no desenvolvimento que impede as crianças de avançar dentro do sistema educativo regular e, em consequência, de progredir para uma vida adulta harmoniosa. Qual é a contribuição da Psicologia para a resolução dos problemas do insucesso escolar? - Compreender o desenvolvimento desviante e a origem das perturbações e suas consequências. - Propor formas de diagnóstico e avaliação das perturbações e dos problemas. - Encontrar métodos de tratamento, nomeadamente terapia, treino ou educação especial, e ainda formas de prevenção. O objetivo deste livro é propor estratégias de intervenção simples, eficazes e cientificamente fundamentadas, apresentando programas de treino, baseados na Psicologia, para o ensino individual de crianças com problemas de insucesso escolar, nomeadamente a teoria da aprendizagem cognitivo- -comportamental.

The integration of visual and auditory spatial information is important for building an accurate perception of the external world, but the fundamental mechanisms governing such audiovisual interaction have only partially been resolved. The earliest interface between auditory and visual processing pathways is in the midbrain, where the superior (SC) and inferior colliculi (IC) are reciprocally connected in an audiovisual loop. Here, we investigate the mechanisms of audiovisual interaction in the midbrain by recording neural signals from the SC and IC simultaneously in anesthetized ferrets. Visual stimuli reliably produced band-limited phase locking of IC local field potentials (LFPs) in two distinct frequency bands: 6-10 and 15-30 Hz. These visual LFP responses co-localized with robust auditory responses that were characteristic of the IC. Imaginary coherence analysis confirmed that visual responses in the IC were not volume-conducted signals from the neighboring SC. Visual responses in the IC occurred later than retinally driven superficial SC layers and earlier than deep SC layers that receive indirect visual inputs, suggesting that retinal inputs do not drive visually evoked responses in the IC. In addition, SC and IC recording sites with overlapping visual spatial receptive fields displayed stronger functional connectivity than sites with separate receptive fields, indicating that visual spatial maps are aligned across both midbrain structures. Reciprocal coupling between the IC and SC therefore probably serves the dynamic integration of visual and auditory representations of space.

Magnetic moment measurements of picosecond states generally make use of the huge transient magnetic fields which fast nuclei experience during their passage through a ferromagnetic foil. Based on the Recoil Distance Transient Field (RDTF) method previously pioneered by the Gottingen group, we propose the Doppler Shift Transient Field (DSTF) method to measure g-factors of short-lived high-spin states excited in a heavy ion fusion reaction at a high recoil velocity. This method can be used whenever the state is populated by fast discrete feeder transitions γ2. By measuring the Larmor precession of the decay γ-ray γ1 with a gate set on the Doppler shifted tail of γ2, one selects events of high recoil velocity (= high transient field) and avoids, to a large extent, the uncertainties of delayed side and cascade feedings inherent in heavy-ion fusion reactions. Estimates are given for the DSTF precessions in 102Cd and 74Br.

The origin of asymmetric clinical manifestation of symptoms in patients suffering from cervical dystonia (CD) is hitherto poorly understood. Dysregulated neuronal activity in the basal ganglia has been suggested to have a role in the pathophysiology of CD. Here, we re-assessed the question to what extent relative changes occur in the direct versus indirect basal ganglia pathway in CD, whether these circuit changes are lateralized, and how these alterations relate to CD symptoms. To this end, we recorded ongoing single cell and local field potential (LFP) activity from the external (GPe) and internal pallidal segment (GPi) of thirteen CD patients undergoing microelectrode-guided stereotactic surgery for deep brain stimulation in the GPi. We compared pallidal recordings from CD patients operated under local anaesthesia (LA) with those obtained in CD patients operated under general anaesthesia (GA). In awake patients, mean GPe discharge rate (52 Hz) was lower than that of GPi (72 Hz). Mean GPi discharge ipsilateral to the side of head turning was higher than contralateral and correlated with torticollis symptom severity. Lateralized differences were absent at the level of the GPe and in recordings from patients operated under GA. Furthermore, in the GPi of CD patients there was a subpopulation of theta-oscillatory cells with unique bursting characteristics. Power and coherence of GPe- and GPi-LFPs were dominated by a theta peak and also exhibited band-specific interhemispheric differences. Strong cross-frequency coupling of low-gamma amplitude to theta phase was a feature of pallidal LFPs recorded under LA, but not GA. These results indicate that CD is associated with an asymmetric pallidal outflow. Based on the finding of symmetric neuronal discharges in the GPe, we propose that an imbalanced interhemispheric direct pathway gain may be involved in CD pathophysiology.

Aims: To assess placental transfer of antibodies to the child at birth and at 2 months of age. Materials and methods: For the quantification of anti-PT IgG antibodies, we used an indirect enzyme-linked immunosorbent assay standardized by The National Institute of Epidemiologic Diagnosis and Reference (InDRE). Samples were considered negative from 0 to 48 IU/mL, indeterminate from 49 to 93 IU/mL and positive at ≥94 IU/mL. We performed a cross-sectional assessment of anti-PT IgG antibody levels in the mother, umbilical cord, and child. Results: There was a higher concentration of IgG anti-TP in the umbilical cord (4.3%) and in the mother (1.4%), but a total absence was observed in the child (0%). Conclusion: The vulnerability of children to Bordetella pertussis shows the need to implement effective immunization strategies, whether actively, in the child, or passively through the mother, adolescents, and adults who are in contact with the child.

A review of the main advances of disaster Psychology, on the background of the situation of the subject in 1985, when an erthquake destroyed a part of Mexico City causing thousands of victims

A set of procedures to evaluate skills of blind children for a further training.

Monte Carlo simulated side feeding times are compared with experimental values in 75Br and 77Rb. The simulation predicts that τ≈τSF. Neither of these nuclei behave in exactly this way and 75Br has an extremely different behaviour. This fact should be a fingerprint of different continuum structures.

An analysis of the application of behavior modification in the training of basic skills, self-care, language and social skills in children with intellectual disabilities

An analysis of the huge problems for the education of persons with intellectual disabilities in Mexico and some proposals.

An analysis of the development of Psychology in Mexico in a period of expansion.

An analysis of Psychology in Mexico

A reflection on the state of Psychology in Mexico and the role of Psychologists on the background of social and political urgent problems