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1.
Rev Neurol ; 69(4): 159-166, 2019 Aug 16.
Article in Spanish | MEDLINE | ID: mdl-31334559

ABSTRACT

Interest in the causal relation between consciousness and the underlying neuronal activity has grown in recent decades. Numerous experimental studies have been carried out on the brain structures and networks underlying consciousness in animal models, in patients with brain damage and with very precise functional neuroimaging. In spite of the great multitude of findings, there is no theoretical proposal that integrates this knowledge under a coherent theoretical framework based on the evidence obtained. Existing theories offer a dismembered view of consciousness, since they pose causal explanations that do not include a global functional perspective of the interaction of the different brain networks involved in consciousness. This work offers a theoretical framework that integrates the empirical knowledge, generated in recent decades, into a neurofunctional model of consciousness. This model represents consciousness as an epiphenomenon resulting from the sequential activation of different neural loops that are formed by specific brain structures and networks which receive feedback from their own operations in order to reconfigure their own functional states and the entire system. The ascending reticular activating system, the thalamocortical networks and the cortico-cortical networks sustain cognitive processes that are differentiated, although highly dependent and fundamental for the final experience of consciousness. All these systems form a single physiological space where the individual can deploy different cognitive skills that allow the emergence of complex behaviours such as language, thought and social cognition.


TITLE: Modelo neurofuncional de la conciencia: bases neurofisiologicas y cognitivas.El interes por la relacion causal existente entre la conciencia y la actividad neuronal subyacente ha aumentado en las ultimas decadas. Se han llevado a cabo numerosos estudios experimentales en modelos animales, en pacientes con daño cerebral y con neuroimagen funcional con una excelente precision sobre las estructuras y redes cerebrales que subyacen a la conciencia. A pesar de la gran multitud de hallazgos, no existe una propuesta teorica que integre este conocimiento bajo un marco teorico coherente basado en las evidencias obtenidas. Las teorias existentes ofrecen una vision desmembrada de la conciencia, ya que plantean explicaciones causales que no incluyen una perspectiva funcional global sobre la interaccion del conjunto de redes cerebrales involucradas en la conciencia. Este trabajo ofrece un marco teorico que integra el conocimiento empirico, generado en las ultimas decadas, en un modelo neurofuncional de la conciencia. Este modelo representa la conciencia como un epifenomeno resultante de la activacion secuencial de diferentes bucles neuronales que estan formados por estructuras y redes cerebrales especificas retroalimentadas por sus propias operaciones para poder reconfigurar sus propios estados funcionales y todo el sistema. El sistema reticular activador ascendente, las redes talamocorticales y las redes corticocorticales sostienen procesos cognitivos diferenciados, aunque altamente dependientes y basicos para la experiencia final de conciencia. Todos estos sistemas forman un unico espacio fisiologico en donde el individuo puede desplegar diferentes habilidades cognitivas que permiten la emergencia de conductas complejas como el lenguaje, el pensamiento y la cognicion social.


Subject(s)
Consciousness/physiology , Models, Neurological , Models, Psychological , Cerebral Cortex/physiology , Emotions/physiology , Feedback, Physiological , Higher Nervous Activity/physiology , Humans , Memory/physiology , Neural Pathways/physiology , Psychophysiology , Thalamus/physiology
2.
Rev Neurol ; 66(S01): S51-S56, 2018 Mar 01.
Article in Spanish | MEDLINE | ID: mdl-29516453

ABSTRACT

INTRODUCTION: From a differential perspective, high intellectual ability is an expression of intellectual functioning with characteristic functional correlates and structural correlates of the underlying neural activity that suggests an improved executive capacity as a relevant characteristic, highlighting in it a more effective working memory. DEVELOPMENT: The neuroscientific evidences about the neural mechanisms that can explain the differences are analyzed between the intellectual functioning of the high intellectual ability and the typical intellectual capacity. The possibilities that offer the recording of evoked potentials to capture fundamental mental processes that allow explain the differences between them are put under review. CONCLUSIONS: Neuroscientific evidences through electroencephalography or other mental imagery techniques show that the brain, as a structural correlate of high intellectual abilities, has greater neural efficiency, interconnectivity and differences in the cytoarchitecture. It is a brain that captures, understands and interprets reality in a qualitatively different manner. But the neural differences are structural and the high intellectual capacity emerges from its plasticity functional. That is, it is a brain prepared for better executive regulation that is not always directly related with excellence and the eminent manifestation of its potentiality because it requires other conditioning factors such as motivation, the organization of knowledge, personal traits of temperament or perfectionism, and exogenous conditions.


TITLE: Neurofuncionalidad ejecutiva: estudio comparativo en las altas capacidades.Introduccion. Desde una perspectiva diferencial, la alta capacidad intelectual es una expresion del funcionamiento intelectual con unos correlatos funcionales caracteristicos y unos correlatos estructurales de la actividad neural subyacente que sugieren una capacidad ejecutiva mejorada como caracteristica relevante, destacando en ella una memoria de trabajo mas eficaz. Desarrollo. Se analizan las evidencias neurocientificas sobre los mecanismos neurales que pueden explicar las diferencias entre el funcionamiento intelectual de la alta capacidad intelectual y la capacidad intelectual tipica, y se revisan las posibilidades que ofrece el registro de potenciales evocados para apresar procesos mentales fundamentales que permitan explicar las diferencias entre ellas. Conclusiones. Las evidencias neurocientificas mediante electroencefalografia u otras tecnicas de imagineria mental muestran que el cerebro, como correlato estructural de la alta capacidad intelectual, tiene mayor eficiencia neural, interconectividad y diferencias en la citoarquitectura. Es un cerebro que captura, comprende e interpreta la realidad de forma cualitativamente diferente. Pero las diferencias neurales son estructurales y la alta capacidad intelectual emerge de su plasticidad funcional. Es decir, es un cerebro preparado para una mejor regulacion ejecutiva que no siempre guarda relacion directa con la excelencia y la eminente manifestacion de su potencialidad porque precisa de otros condicionantes como la motivacion, la organizacion del conocimiento, rasgos personales de temperamento o perfeccionismo, y condicionantes exogenos.


Subject(s)
Executive Function/physiology , Higher Nervous Activity/physiology , Intelligence/physiology , Brain/diagnostic imaging , Brain/physiology , Cognition/physiology , Decision Making , Electroencephalography , Evoked Potentials/physiology , Humans , Membrane Potentials/physiology , Neuroimaging , Neuronal Plasticity
3.
Physiol Rev ; 98(1): 239-389, 2018 01 01.
Article in English | MEDLINE | ID: mdl-29351512

ABSTRACT

Astrocytes are neural cells of ectodermal, neuroepithelial origin that provide for homeostasis and defense of the central nervous system (CNS). Astrocytes are highly heterogeneous in morphological appearance; they express a multitude of receptors, channels, and membrane transporters. This complement underlies their remarkable adaptive plasticity that defines the functional maintenance of the CNS in development and aging. Astrocytes are tightly integrated into neural networks and act within the context of neural tissue; astrocytes control homeostasis of the CNS at all levels of organization from molecular to the whole organ.


Subject(s)
Astrocytes/physiology , Animals , Astrocytes/cytology , Biological Evolution , Higher Nervous Activity/physiology , Homeostasis , Humans , Ion Channels/metabolism , Membrane Potentials , Receptors, Cell Surface/metabolism
4.
J Clin Exp Neuropsychol ; 40(2): 173-182, 2018 03.
Article in English | MEDLINE | ID: mdl-28511576

ABSTRACT

INTRODUCTION: The Barrow Neurological Institute (BNI) Screen for Higher Cerebral Functions (BNIS) has been translated into several languages and found useful in evaluating multiple domains of cognitive and affective dysfunction, particularly in neuro-rehabilitation settings. Normative data from countries with high literacy rates have reported strikingly similar mean level of performance scores on this test, with age typically correlating higher with total score performance than education. In the present study, we obtain convenience sample normative data from a native Brazilian population on a Portuguese translation of the BNIS (i.e., BNIS-PT). METHOD: The BNIS was translated into Portuguese by two native speaking Portuguese neuropsychologists who were also fluent in English. It was then administered to 201 normally functioning native Brazilian individuals who varied considerably in age and formal educational training. RESULTS: The mean BNIS total score was similar to what previous studies reported, but primarily in younger adults with at least 12 years of formal education. In this Brazilian sample, the correlation of educational level and BNIS total score was r = .68, p < .001. The correlation of age and BNIS total score was r = -.36, p < .001. This is the opposite pattern to that observed in previous standardization studies. The strong correlation of education with performance in various subtests was observed in all age groups (ages ranging from 15 to 85 years). CONCLUSION: This standardization study provides guidelines for calculating expected average performance levels on the BNIS-PT for Brazilian individuals with varying degrees of age and education. Educational level positively correlated with test performance on the BNIS-PT and was repeatedly observed to overshadow the effects of age, suggesting its important role in the development of higher cerebral functions in multiple domains in a Brazilian sample of normally functioning individuals.


Subject(s)
Cognition Disorders/diagnosis , Cross-Cultural Comparison , Higher Nervous Activity/physiology , Mood Disorders/diagnosis , Neuropsychological Tests/statistics & numerical data , Psychometrics/statistics & numerical data , Translating , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Brazil , Cerebral Cortex/physiopathology , Cognition Disorders/physiopathology , Correlation of Data , Educational Status , Female , Humans , Male , Middle Aged , Mood Disorders/physiopathology , Reproducibility of Results , Young Adult
5.
Hum Mov Sci ; 50: 62-72, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27788372

ABSTRACT

In the present experiment, we aimed to evaluate the interactive effect of performing a cognitive task simultaneously with a manual task requiring either high or low steadiness on APRs. Young volunteers performed the task of recovering upright balance following a mechanical perturbation provoked by unanticipatedly releasing a load pulling the participant's body backwards. The postural task was performed while holding a cylinder steadily on a tray. One group performed that task under high (cylinder' round side down) and another one under low (cylinder' flat side down) manual steadiness constraint. Those tasks were evaluated in the conditions of performing concurrently a cognitive numeric subtraction task and under no cognitive task. Analysis showed that performance of the cognitive task led to increased body and tray displacement, associated with higher displacement at the hip and upper trunk, and lower magnitude of activation of the GM muscle in response to the perturbation. Conversely, high manual steadiness constraint led to reduced tray velocity in association with lower values of trunk displacement, and decreased rotation amplitude at the ankle and hip joints. We found no interactions between the effects of the cognitive and manual tasks on APRs, suggesting that they were processed in parallel in the generation of responses for balance recovery. Modulation of postural responses from the manual and cognitive tasks indicates participation of higher order neural structures in the generation of APRs, with postural responses being affected by multiple mental processes occurring in parallel.


Subject(s)
Attention/physiology , Cognition/physiology , Postural Balance/physiology , Problem Solving/physiology , Psychomotor Performance/physiology , Weight-Bearing/physiology , Adolescent , Adult , Female , Higher Nervous Activity/physiology , Humans , Male , Young Adult
7.
Praxis (Bern 1994) ; 105(12): 703-8, 2016 Jun 08.
Article in German | MEDLINE | ID: mdl-27269777

ABSTRACT

Migraine is a complex neurologic disorder by which several systems of the central nervous system (autonomous system, affective, cognitive, sensoric and motoric system) may be affected on different levels. Around a fourth of the patients have migraine aura. The most common aura is the visual aura, followed by sensoric aura. But motoric deficits as well as deficits of higher cortical centers (disorders of thinking, orientation, coherence or concentration) may occur as well. In analogy with a headache calendar, an aura calendar can deliver important help in the diagnostic process of rare migraine manifestations and prevent underdiagnosis of unusual migraine manifestations. Complex migraine manifestations are diagnoses of exlusion, and a broad diagnostic work-up is warranted in order to exclude dangerous neurologic pathologies. There are no specific therapeutic recommendations, as there is a lack of randomized controlled studies.


Subject(s)
Migraine Disorders/diagnosis , Migraine with Aura/diagnosis , Brain Stem/physiopathology , Cerebral Cortex/physiopathology , Diagnosis, Differential , Higher Nervous Activity/physiology , Humans , Migraine Disorders/physiopathology , Migraine with Aura/physiopathology , Neurologic Examination
12.
Psicothema ; 26(1): 1-9, 2014.
Article in English | MEDLINE | ID: mdl-24444722

ABSTRACT

BACKGROUND: Models of cognition propose a hierarchical structure for human cognitive processes, in which the sequences of human action are organized into parts or subunits of analysis that can be grouped into progressively more complex, inclusive higher-order functions. This organizational structure from partial to whole may be reflected in the neural representations that underlie human behaviour, and in its genetic underpinnings. The objective of the present study was to explore a putative hierarchical organization of the genetic influences underlying cognitive domains. METHOD: Thirty four studies of the heritability of cognition on population-based samples were reviewed, which included measures of intelligence, verbal and performance abilities, memory, working memory and processing speed. RESULTS: Specific cognitive domains showed diverse proportions of genetic underpinnings such that higher-order cognitive functions present high heritability estimates, whereas lower-order functions respond to small/moderate heritability estimates. CONCLUSIONS: Based on current understanding of the developmental processes of the neurobiological substrates of human cognition, the genetic contributions to cognitive abilities seem to be organized in line with the ontogenic maturation of the brain. We discuss the large genetic control of the combinatory capacity of basic cognitive functions, and its interaction with environmental influences.


Subject(s)
Brain/physiology , Cognition/physiology , Adolescent , Adult , Aged , Aged, 80 and over , Brain/embryology , Brain/growth & development , Brain Mapping , Child , Child, Preschool , Gene-Environment Interaction , Higher Nervous Activity/genetics , Higher Nervous Activity/physiology , Humans , Intelligence/genetics , Memory , Middle Aged , Models, Neurological , Models, Psychological
13.
Gerodontology ; 30(2): 133-40, 2013 Jun.
Article in English | MEDLINE | ID: mdl-22512354

ABSTRACT

OBJECTIVE: The aim of the present study was to elucidate relationships between higher-level functional capacity and dental health behaviours in community-dwelling older adults. BACKGROUND: In ageing society, it is necessary to promote oral health in the elderly, because good oral health is a significant contributing factor to good general health. Higher-level functional capacity has been considered a crucial factor for successful independent living in the elderly. We hypothesised that functional capacity is a significant indicator of dental health behaviours. METHODS: Three hundred and thirty-eight adults aged 65 years or older were enrolled in this study. Higher-level functional capacity was evaluated using the Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-index). Univariate and multivariate models were constructed with dental health behaviours, such as regular visits to a dentist, brushing frequency and use of extra cleaning devices, as the dependent variable, and the total TMIG-index score and its subcategory scores as the principal independent variable. RESULTS: Univariate logistic regression analysis demonstrated a significant correlation between low TMIG-index and 'intellectual activity' subcategory scores to lack of regular visits to a dentist and not using extra cleaning devices. Using a multivariate model, significant relationships remained after adjusting for a number of variables including demographics, medical status, lifestyle and number of remaining teeth. CONCLUSION: Intellectual activity of higher-level functional capacity may be an accurate indicator of dental health behaviours in community-dwelling older adults. Intellectual activity should be taken into consideration to effectively promote oral health behaviours and oral hygiene in elderly persons living independently.


Subject(s)
Health Behavior , Independent Living , Mental Processes/physiology , Oral Health , Aged , Chronic Disease , Dental Care for Aged , Dental Devices, Home Care , Dentition , Educational Status , Employment , Family Characteristics , Female , Geriatric Assessment , Health Promotion , Health Status , Higher Nervous Activity/physiology , Humans , Interpersonal Relations , Life Style , Male , Mental Competency , Oral Hygiene , Self Care , Toothbrushing
14.
Lik Sprava ; (7): 117-20, 2013.
Article in Russian | MEDLINE | ID: mdl-25509925

ABSTRACT

The material of this article provides information about the basics of hygiene conditions and nature of intellectual loads of students of secondary schools in the perception of information in a foreign language. Are the most favorable conditions for the successful training of perception and assimilation of information supplied in the course of the learning process in one foreign language or some more different ones? It was found that the process of perception and assimilation of educational information in foreign languages is associated with some degree of mental and emotional stress of students. At the same time, the effectiveness of the learning process depends on the degree of stress. Certain parameters of the psychological and emotional stress students usually have a stimulating effect on their central nervous system. Another level, the psychological and emotional stress of students on the contrary, causes a braking effect of functional activity of the relevant structures of the central nervous system of students and reduces the effectiveness of training.


Subject(s)
Higher Nervous Activity/physiology , Intelligence/physiology , Learning/physiology , Multilingualism , Stress, Psychological , Students/psychology , Educational Measurement , Humans , Psychophysiology , Stress, Psychological/etiology , Stress, Psychological/psychology
15.
Article in Russian | MEDLINE | ID: mdl-22690543

ABSTRACT

The new trend in brain research designated as brain reading is considered. This research deals with decoding the informational content of the brain processing via its physiological parameters. Such studies are based on rather complicated methods of mathematical analysis. Single records rather than averaged data are used to reveal their content. Three main streams of studies are distinguished, i.e. the object classification, the emotion recognition and brainotyping. Particularly, the studies directed to recognizing the type of thinking via EEG spectra, carried out in the author's laboratory, are reviewed. The possible outcome of the brain reading technique is considered. Finally it is argued that in the future, the broad application of this technique needs to be controlled with some ethical rules.


Subject(s)
Brain Mapping/ethics , Brain Mapping/trends , Brain/physiology , Higher Nervous Activity/physiology , Pattern Recognition, Physiological/physiology , Electroencephalography/methods , Humans , Magnetic Resonance Imaging
16.
Zh Vyssh Nerv Deiat Im I P Pavlova ; 62(2): 197-207, 2012.
Article in Russian | MEDLINE | ID: mdl-22690549

ABSTRACT

In the course of analysis of the conjugate unit activity of simultaneously recorded neurons in the sensorimotor cortex of rabbits, 22 closed neural circuits consisting of 3 or 4 neurons were considered. In the model of the defensive dominanta, 1-3 weeks after imposing rhythmic (2 s) activity to a rabbit, the distribution of coincident impulses was analyzed in real time. It was found out that the events when the coincident impulses of neural pairs were generated with two-second intervals could be shifted in time and space over a closed circuit of neurons in one direction. Two-second intervals between the coincident impulses of the neighboring pairs could be conjugate, i.e. the end of one interval in one pair coincided with the beginning of a two-second interval in the next pair. Conjugate intervals of the neighboring neural pairs could promote a pass-through of the information on the stimulus properties over the closed neuronal circuit, thus completing a full cycle. The longest passes-through lasted from 10 and 12 s. Also, more intricate variants of the information transfer were revealed. Thus, not only passes-through of the two- second intervals between the neuronal pairs were observed, but also, coincident impulses repeatedly occurred with this interval in some of the pairs of the circuits. The longest transitions lasted 16 and 22 s.


Subject(s)
Auditory Cortex/physiology , Motor Cortex/physiology , Nerve Net/physiology , Somatosensory Cortex/physiology , Animals , Electrodes , Evoked Potentials/physiology , Higher Nervous Activity/physiology , Male , Neurons/physiology , Physical Stimulation/methods , Rabbits , Time Factors
17.
Aviakosm Ekolog Med ; 46(1): 5-16, 2012.
Article in Russian | MEDLINE | ID: mdl-22624475

ABSTRACT

The article presents the analysis of difficulty with studying the CNS functional changes caused by ionizing radiations solely and in combination with the other spaceflight factors, and discusses optional methods of modeling the basic elements of operator's work in experiments with animals, primates specifically, as well as of data extrapolation on humans.


Subject(s)
Central Nervous System/radiation effects , Higher Nervous Activity/radiation effects , Space Flight , Animals , Central Nervous System/physiology , Haplorhini , Higher Nervous Activity/physiology , Humans , Hypokinesia/physiopathology , Models, Biological , Radiation, Ionizing , Rats , Species Specificity , Stress, Physiological/radiation effects , Time Factors , Weightlessness
18.
Usp Fiziol Nauk ; 42(3): 46-64, 2011.
Article in Russian | MEDLINE | ID: mdl-21950008

ABSTRACT

In work the hypothesis according to which different forms of goal-directed behavior develop depending on the basis of the undervaluation/supervaluation of reinforcement by brain abilities at the conditions of its achievement uncertainty. From these positions such opposite biological characteristics of the subject, as impulsiveness/self-control, care/propensity to risk on which basis there are individually typological features in behavior of the person and animals are considered. In the article, our experimental data on animals and the persons by behavioral techniques and results of last years on research of neural networks of animal cortical and subcortical brain structures depending on the strategy in choice behavior are also analyzed.


Subject(s)
Brain/physiology , Choice Behavior/physiology , Conditioning, Operant/physiology , Higher Nervous Activity/physiology , Motivation/physiology , Animals , Behavior Control , Behavior, Animal/physiology , Birds/physiology , Cats , Child , Child, Preschool , Dogs , Feeding Behavior , Humans , Neurons/physiology , Reinforcement, Psychology
19.
Radiats Biol Radioecol ; 51(2): 233-42, 2011.
Article in Russian | MEDLINE | ID: mdl-21674950

ABSTRACT

The dynamics of using a stabilized motor defensive conditioned reflex of active avoidance in "shuttle-box" in rats after the total influence of high energy electrons and gamma-rays at a dose of 100 Gy and a modifying influence of the two most important factors forming the functional status of the central nervous system: the stage of the conditioned reflex consolidation and typological peculiarities of the higher nervous activity have been investigated. The influence of both types of ionizing radiation has been shown to cause far more profound disturbances of non consolidated conditioned reflexes in comparison with the automatized conditioned reflexes and provoke an inverted picture of disturbances in the animals with opposed peculiarities of the higher nervous activity. The qualitative picture of the dynamics of disturbances that are caused by these types of radiation is identical. In summary, the studied conditions that form the functional status of the central nervous system determine the nature of neuroradiation syndrome to a greater extent than differences in the effectiveness of these types of radiation.


Subject(s)
Central Nervous System/radiation effects , Electrons/adverse effects , Gamma Rays/adverse effects , Higher Nervous Activity/radiation effects , Radiation Injuries, Experimental/physiopathology , Animals , Behavior, Animal/radiation effects , Central Nervous System/physiology , Higher Nervous Activity/physiology , Male , Radiation Dosage , Rats , Rats, Wistar , Time Factors , Whole-Body Irradiation
20.
Fiziol Zh (1994) ; 57(1): 88-93, 2011.
Article in Ukrainian | MEDLINE | ID: mdl-21516838

ABSTRACT

The dynamics of the speed formation of the central information processing (CIP) and its connection with functional mobility of nervous processes (FMNP) was investigated among the persons aged 7-20. The indexes of CIP and FMNP among the children, teenagers and youngsters were found to increase gradually and to reach maximum development at the age of 19-20. Statistically significant differences of the CIP speed were found in all age groups of the investigated persons with different levels of FNMP. The persons with high level of FNMP were characterized with reliably high indexes of CIP compared with subjects with the low level of investigated typological properties of high nervous activity (HNA). The correlation proved the reliable relationships between investigated variables. The general age-related conformities in forming CIP and FMNP were established favoring the genetically determined program for development of these nervous system properties. There is a reason to confirm that the index of CIP speed characterizes individual features of information processing and reflects the typological properties of HNA side by side with FMNP.


Subject(s)
Aging/physiology , Mental Processes/physiology , Nervous System Physiological Phenomena , Adolescent , Child , Higher Nervous Activity/physiology , Humans , Psychomotor Performance/physiology , Time Factors , Young Adult
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