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Attention, predictions and expectations and their violation: attentional control in the human brain

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889193677 Year: Pages: 211 DOI: 10.3389/978-2-88919-367-7 Language: English
Publisher: Frontiers Media SA
Subject: Neurology --- Science (General)
Added to DOAB on : 2015-11-19 16:29:12
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In the burdened scenes of everyday life, our brains must select from among many competing inputs for perceptual synthesis - so that only the most relevant receive full attention and irrelevant (distracting) information is suppressed. At the same time, we must remain responsive to salient events outside our current focus of attention - and balancing these two processing modes is a fundamental task our brain constantly needs to solve. Both the physical saliency of a stimulus, as well as top-down predictions about imminent sensations crucially influence attentional selection and consequently the response to unexpected events. Research over recent decades has identified two separate brain networks involved in predictive top-down control and reorientation to unattended events (or oddball stimuli): the dorsal and ventral fronto-parietal attention systems of the human brain. Moreover, specific electrophysiological brain responses are known to characterize attentional orienting as well as the processing of deviant stimuli. However, many key questions are outstanding. What are the exact functional differences between these cortical attention systems? How are they lateralised in the two hemispheres? How do top-down and bottom-up signals interact to enable flexible attentional control? How does structural damage to one system affect the functionality of the other in brain damaged patients? Are there sensory-specific and supra-modal attentional systems in the brain? In addition to these questions, it is now accepted that brain responses are not only affected by the saliency of external stimuli, but also by our expectations about sensory inputs. How these two influences are balanced, and how predictions are formed in cortical networks, or generated on the basis of experience-dependent learning, are intriguing issues. In this Research Topic, we aim to collect innovative contributions that shed further light on the (cortical) mechanisms of attentional control in the human brain. In particular, we would like to encourage submissions that investigate the behavioural correlates, functional anatomy or electrophysiological markers of attentional selection and reorientation. Special emphasis will be given to studies investigating the context-sensitivity of these attentional processes in relation to prior expectations, trial history, contextual cues or physical saliency. We would like to encourage submissions employing different research methods (psychophysical recordings, neuroimaging techniques such as fMRI, MEG, EEG or ECoG, as well as neurostimulation methods such as TMS or tDCS) in healthy volunteers or neurological patients. Computational models and animal studies are also welcome. Finally, we also welcome submission of meta-analyses and reviews articles that provide new insights into, or conclusions about recent work in the field.

The cognitive and neural organisation of speech processing

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889197750 Year: Pages: 146 DOI: 10.3389/978-2-88919-774-3 Language: English
Publisher: Frontiers Media SA
Subject: Neurology --- Science (General)
Added to DOAB on : 2016-04-07 11:22:02
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Speech production and perception are two of the most complex actions humans perform. The processing of speech is studied across various fields and using a wide variety of research approaches. These fields include, but are not limited to, (socio)linguistics, phonetics, cognitive psychology, neurophysiology, and cognitive neuroscience. Research approaches range from behavioural studies to neuroimaging techniques such as Magnetoencephalography, electroencephalography (MEG/EEG) and functional Magnetic Resonance Imaging (fMRI), as well as neurophysiological approaches, such as the recording of Motor Evoked Potentials (MEPs), and Transcranial Magnetic Stimulation (TMS). Each of these approaches provides valuable information about specific aspects of speech processing. Behavioural testing can inform about the nature of the cognitive processes involved in speech processing, neuroimaging methods show where (fMRI and MEG) in the brain these processes take place and/or elucidate on the time-course of activation of these brain areas (EEG and MEG), while neurophysiological methods (MEPs and TMS) can assess critical involvement of brain regions in the cognitive process. Yet, what is currently unclear is how speech researchers can combine methods such that a convergent approach adds to theory/model formulation, above and beyond the contribution of individual component methods? We expect that such combinations of approaches will significantly forward theoretical development in the field. The present research topic comprise a collection of manuscripts discussing the cognitive and neural organisation of speech processing, including speech production and perception at the level of individual speech sounds, syllables, words, and sentences. Our goal was to use findings from a variety of disciplines, perspectives, and approaches to gain a more complete picture of the organisation of speech processing. The contributions are grouped around the following five main themes: 1) Spoken language comprehension under difficult listening conditions; 2) Sub-lexical processing; 3) Sensorimotor processing of speech; 4) Speech production. The contributions used a variety of research approaches, including behavioural experiments, fMRI, EEG, MEG, and TMS. Twelve of the 14 contributions were on speech perception processing, and the remaining two examined speech production. This Research Topic thus displays a wide variety of topics and research methods and this comprehensive approach allows an integrative understanding of currently available evidence as well as the identification of concrete venues for future research.

Keywords

Speech --- Perception --- production --- TMS --- fMRI --- EEG --- MEG --- behavioural

Augmentation of Brain Function: Facts, Fiction and Controversy. Volume I: Brain-Machine Interfaces

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889456147 Year: Pages: 666 DOI: 10.3389/978-2-88945-614-7 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Neurology
Added to DOAB on : 2019-01-23 14:53:43
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Volume I, entitled “Augmentation of Brain Functions: Brain-Machine Interfaces”, is a collection of articles on neuroprosthetic technologies that utilize brain-machine interfaces (BMIs). BMIs strive to augment the brain by linking neural activity, recorded invasively or noninvasively, to external devices, such as arm prostheses, exoskeletons that enable bipedal walking, means of communication and technologies that augment attention. In addition to many practical applications, BMIs provide useful research tools for basic science. Several articles cover challenges and controversies in this rapidly developing field, such as ways to improve information transfer rate. BMIs can be applied to the awake state of the brain and to the sleep state, as well. BMIs can augment action planning and decision making. Importantly, BMI operations evoke brain plasticity, which can have long-lasting effects. Advanced neural decoding algorithms that utilize optimal feedback controllers are key to the BMI performance. BMI approach can be combined with the other augmentation methods; such systems are called hybrid BMIs. Overall, it appears that BMI will lead to many powerful and practical brain-augmenting technologies in the future.

Augmentation of Brain Function: Facts, Fiction and Controversy. Volume II: Neurostimulation and Pharmacological Approaches

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889456154 Year: Pages: 403 DOI: 10.3389/978-2-88945-615-4 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Neurology
Added to DOAB on : 2019-01-23 14:53:43
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The Volume II is entitled “Neurostimulation and pharmacological approaches”. This volume describes augmentation approaches, where improvements in brain functions are achieved by modulation of brain circuits with electrical or optical stimulation, or pharmacological agents. Activation of brain circuits with electrical currents is a conventional approach that includes such methods as (i) intracortical microstimulation (ICMS), (ii) transcranial direct current stimulation (tDCS), and (iii) transcranial magnetic stimulation (TMS). tDCS and TMS are often regarded as noninvasive methods. Yet, they may induce long-lasting plastic changes in the brain. This is why some authors consider the term “noninvasive” misleading when used to describe these and other techniques, such as stimulation with transcranial lasers. The volume further discusses the potential of neurostimulation as a research tool in the studies of perception, cognition and behavior. Additionally, a notion is expressed that brain augmentation with stimulation cannot be described as a net zero sum proposition, where brain resources are reallocated in such a way that gains in one function are balanced by costs elsewhere. In recent years, optogenetic methods have received an increased attention, and several articles in Volume II cover different aspects of this technique. While new optogenetic methods are being developed, the classical electrical stimulation has already been utilized in many clinically relevant applications, like the vestibular implant and tactile neuroprosthesis that utilizes ICMS. As a peculiar usage of neurostimulation and pharmacological methods, Volume II includes several articles on augmented memory. Memory prostheses are a popular recent development in the stimulation-based BMIs. For example, in a hippocampal memory prosthesis, memory content is extracted from hippocampal activity using a multiple-input, multiple-output non-linear dynamical model. As to the pharmacological approaches to augmenting memory and cognition, the pros and cons of using nootropic drugs are discussed.

Augmentation of Brain Function: Facts, Fiction and Controversy. Volume III: From Clinical Applications to Ethical Issues and Futuristic Ideas

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889456161 Year: Pages: 338 DOI: 10.3389/978-2-88945-616-1 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Neurology
Added to DOAB on : 2019-01-23 14:53:43
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The final volume in this tripartite series on Brain Augmentation is entitled “From Clinical Applications to Ethical Issues and Futuristic Ideas”. Many of the articles within this volume deal with translational efforts taking the results of experiments on laboratory animals and applying them to humans. In many cases, these interventions are intended to help people with disabilities in such a way so as to either restore or extend brain function. Traditionally, therapies in brain augmentation have included electrical and pharmacological techniques. In contrast, some of the techniques discussed in this volume add specificity by targeting select neural populations. This approach opens the door to where and how to promote the best interventions. Along the way, results have empowered the medical profession by expanding their understanding of brain function. Articles in this volume relate novel clinical solutions for a host of neurological and psychiatric conditions such as stroke, Parkinson’s disease, Huntington’s disease, epilepsy, dementia, Alzheimer’s disease, autism spectrum disorders (ASD), traumatic brain injury, and disorders of consciousness. In disease, symptoms and signs denote a departure from normal function. Brain augmentation has now been used to target both the core symptoms that provide specificity in the diagnosis of a disease, as well as other constitutional symptoms that may greatly handicap the individual. The volume provides a report on the use of repetitive transcranial magnetic stimulation (rTMS) in ASD with reported improvements of core deficits (i.e., executive functions). TMS in this regard departs from the present-day trend towards symptomatic treatment that leaves unaltered the root cause of the condition. In diseases, such as schizophrenia, brain augmentation approaches hold promise to avoid lengthy pharmacological interventions that are usually riddled with side effects or those with limiting returns as in the case of Parkinson’s disease. Brain stimulation can also be used to treat auditory verbal hallucination, visuospatial (hemispatial) neglect, and pain in patients suffering from multiple sclerosis. The brain acts as a telecommunication transceiver wherein different bandwidth of frequencies (brainwave oscillations) transmit information. Their baseline levels correlate with certain behavioral states. The proper integration of brain oscillations provides for the phenomenon of binding and central coherence. Brain augmentation may foster the normalization of brain oscillations in nervous system disorders. These techniques hold the promise of being applied remotely (under the supervision of medical personnel), thus overcoming the obstacle of travel in order to obtain healthcare. At present, traditional thinking would argue the possibility of synergism among different modalities of brain augmentation as a way of increasing their overall effectiveness and improving therapeutic selectivity. Thinking outside of the box would also provide for the implementation of brain-to-brain interfaces where techniques, proper to artificial intelligence, could allow us to surpass the limits of natural selection or enable communications between several individual brains sharing memories, or even a global brain capable of self-organization. Not all brains are created equal. Brain stimulation studies suggest large individual variability in response that may affect overall recovery/treatment, or modify desired effects of a given intervention. The subject’s age, gender, hormonal levels may affect an individual’s cortical excitability. In addition, this volume discusses the role of social interactions in the operations of augmenting technologies. Finally, augmenting methods could be applied to modulate consciousness, even though its neural mechanisms are poorly understood. Finally, this volume should be taken as a debate on social, moral and ethical issues on neurotechnologies. Brain enhancement may transform the individual into someone or something else. These techniques bypass the usual routes of accommodation to environmental exigencies that exalted our personal fortitude: learning, exercising, and diet. This will allow humans to preselect desired characteristics and realize consequent rewards without having to overcome adversity through more laborious means. The concern is that humans may be playing God, and the possibility of an expanding gap in social equity where brain enhancements may be selectively available to the wealthier individuals. These issues are discussed by a number of articles in this volume. Also discussed are the relationship between the diminishment and enhancement following the application of brain-augmenting technologies, the problem of “mind control” with BMI technologies, free will the duty to use cognitive enhancers in high-responsibility professions, determining the population of people in need of brain enhancement, informed public policy, cognitive biases, and the hype caused by the development of brain- augmenting approaches.

Selected Papers from CUBANNI 2017—“The Fourth International Workshop of Neuroimmunology”

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ISBN: 9783038974871 / 9783038974888 Year: Pages: 170 DOI: 10.3390/books978-3-03897-488-8 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Social Sciences --- Neurology --- Arts in general
Added to DOAB on : 2019-02-04 12:03:12
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Starting from the most interesting papers presented at CUBANNI 2017, the First International Meeting of the Cuban Network of Neuroimmunology, this eBook covers the most up-to-date findings on neuroimmunology research. The topics of the selected papers range from clinical to pre-clinical models, as well as in vitro basic research. Scientific areas covered are autism spectrum disorders, epilepsy, Parkinson’s disease, and seizures, with emphasis on epigenetics and experimental models. Neuroinflammation, neuroplasticity, and neurodegenerative processes, biomarker discovery, and the molecular pathways involved are proposed. Additionally as one of the most current and relevant topics published, Tamara da Silva Vaccaro et al proved relevant results on “Alterations in the MicroRNA and their effects on Epigenetic Regulation and Potential Biomarkers in ASD” and Lázaro Gómez et al also published interesting results on Non-Invasive Brain Stimulation for Children with Autism Spectrum Disorders.

Manipulative approaches to human brain dynamics

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889194797 Year: Pages: 246 DOI: 10.3389/978-2-88919-479-7 Language: English
Publisher: Frontiers Media SA
Subject: Neurology --- Science (General)
Added to DOAB on : 2016-03-10 08:14:33
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In this EBook, we highlight how newly emerging techniques for non-invasive manipulation of the human brain, combined with simultaneous recordings of neural activity, contribute to the understanding of brain functions and neural dynamics in humans. A growing body of evidence indicates that the neural dynamics (e.g., oscillations, synchrony) are important in mediating information processing and networking for various functions in the human brain. Most of previous studies on human brain dynamics, however, show correlative relationships between brain functions and patterns of neural dynamics measured by imaging methods such as electroencephalography (EEG), magnetoencephalography (MEG), near-infrared spectroscopy (NIRS), positron emission tomography (PET) and functional magnetic resonance imaging (fMRI). In contrast, manipulative approaches by non-invasive brain stimulation (NIBS) have been developed and extensively used. These approaches include transcranial magnetic stimulation (TMS) and transcranial electric stimulation (tES) such as transcranial direct current stimulation (tDCS), alternating current stimulation (tACS), and random noise stimulation (tRNS), which can directly manipulate neural dynamics in the intact human brain. Although the neural-correlate approach is a strong tool, we think that manipulative approaches have far greater potential to show causal roles of neural dynamics in human brain functions. There have been technical challenges with using manipulative methods together with imaging methods. However, thanks to recent technical developments, it has become possible to use combined methods such as TMS–EEG coregistration. We can now directly measure and manipulate neural dynamics and analyze functional consequences to show causal roles of neural dynamics in various brain functions. Moreover, these combined methods can probe brain excitability, plasticity and cortical networking associated with information processing in the intact human brain. The contributors to this EBook have succeeded in showcasing cutting-edge studies and demonstrate the huge impact of their approaches on many areas in human neuroscience and clinical applications.

Beyond the simple contrastive analysis: Appropriate experimental approaches for unraveling the neural basis of conscious experience

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889195473 Year: Pages: 129 DOI: 10.3389/978-2-88919-547-3 Language: English
Publisher: Frontiers Media SA
Subject: Psychology --- Science (General)
Added to DOAB on : 2016-01-19 14:05:46
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Contrasting conditions with and without conscious experience has served consciousness research well. However, research based on this simple contrast has led to controversies about the neural basis of conscious experience. One key reason for these ongoing debates seems to be that the simple contrast between conditions with and without consciousness is not specific for unraveling the neural basis of conscious experience, but rather also leads to other processes that precede or follow it. Acknowledging this methodological problem implies that some of the previous research findings about the neural underpinnings of conscious experience are actually reflecting the prerequisites and consequences rather than the direct correlates of conscious perception. Thus, it is required to re-evaluate the previous results to find out which of them are telling us anything about the neural basis of consciousness. But first and foremost, to overcome this methodological problem we need new experimental paradigms that go beyond the simple contrastive analysis or find the ways how some older but well forgotten paradigms may foster a new look at this emerging problem. Accordingly, this research topic is looking for empirical and theoretical contributions that: 1) envision new and suitable experimental approaches to study consciousness that are free from the limitations of the simple contrastive analysis; 2) provide empirical data that help to separate the neural correlates of conscious experience from the prerequisites and consequences of it; 3) help to re-assess previous research findings about the neural correlates of conscious perception in the light of the methodological problems with the traditional contrastive analysis. We hope that the theoretical insights and experimental approaches collected within this Research Topic help us to gain a more refined understanding of the neural basis of conscious experience.

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