1,543 research outputs found

    Cortical Oscillations During a Lateral Balance Perturbation While Walking

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    The role of sensory systems in the cortical control of dynamic balance was examined using electroencephalography (EEG) recordings during balance perturbations while walking. Specifically, we examined the impact of sensory deficits on cortical oscillations using vibratory stimuli to suppress sensory feedback and by comparing cortical oscillations during balance perturbations while walking in people with sensory deficits associated with cervical myelopathy and neurologically intact controls. Balance during walking provides a rich framework for investigating cortical control using EEG during a functionally relevant task. While this approach is promising, substantial technical challenges remain in recording and processing EEG in the noisy, artifact laden environment associated with walking. We therefore first investigated the role of sensory attenuation in healthy, adult controls within the framework of a simple, motor task. We then examined the effectiveness of using independent component analysis and additional machine learning techniques such as clustering and linear classifiers for differentiating noise from actual brain activity in EEG signals during walking. Finally, we examined a more complicated experimental framework using a custom cable-servomotor system to deliver a lateral pull to the waist of participants with cervical myelopathy while walking and measured their cortical activity using high density EEG. We observed that the attenuation of sensory input in healthy controls induced a similar change in beta band modulation as found previously in spinal cord injury for simple movements of the ankle. During walking, large increases in theta band power throughout the cortex were observed to modulate with lateral balance perturbations. Theta band modulations in the frontal areas of the cortex were significantly delayed in time and displayed a more spatially lateralized cortical localization for participants with cervical myelopathy compared to age-matched, healthy controls. The timing of these theta power modulations were significantly correlated with the initiation of a widening step width correction in response to the balance perturbation. Our results support a link between the modulation of cortical oscillations and sensorimotor integration in simple and complex motor paradigms

    The narrative manipulation of human subjectivity : a machinic exploration of psyche as artificial ready-made

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    Avec l’accélération de la production narrative au vingt-et-unième siècle, ainsi que les tentatives d’appropriation des moyens de production et des mythes collectifs par le marché, il y a lieu de questionner l’effet des nouveaux mythes sur la psyché humaine. L’ingestion persistante et soutenue de récits infusés de symboles capitalistes produit une mutation de la subjectivité humaine, dans un mouvement vers une certaine homogénéité. Par une relecture de la Poétique d’Aristote, la première section de cette thèse propose une vision politique de la catharsis, qui théorise le récepteur de toute narration comme programmable et pouvant être guidé vers des attitudes et des postures. Cette conception mène directement à une définition machinique du récit et la notion d’asservissement machinique, qui conçoit la subjectivité humaine comme engagée dans des processus de connectivité où elle perd certains fragments de son unicité. La troisième foulée de cette thèse théorise la société de contrôle de Deleuze et ses héritiers conceptuels, le capitalisme de surveillance et l’ectosubjectivité. Ces deux notions tentent de percevoir le régime de pouvoir du vingt-et-unième siècle, fondé sur les données personnelles et la standardisation de la psyché humaine. Finalement, le quatrième et dernier chapitre de cette recherche se penche sur la notion de vérité telle que décrite par Michel Foucault dans Le Courage de la Vérité. Dans la notion Grecque, et particulièrement son développement platonicien, de parrhēsia, Foucault identifie l’homogénéité d’une vérité basée sur une hiérarchie éthique, et son renversement par les Cyniques en animalité assumée qui ouvre de nouveaux territoires d’existence et de vérité. En somme, ce renversement nous permet de concevoir ce que serait une existence libre, hors d’un régime de vérité qui désubjective et rend homogène.With the acceleration of narrative production in the twenty-first century, as well as the attempted appropriation of means of production and collective myths by market economy, there is an increasing need to question the effect of these new myths on the human psyche. The persistent and sustained ingestion of narratives infused with capitalist symbols produces a transformation of subjectivity, which mutates from unicity to increased standardization. Through a rereading of Aristotle’s Poetics, the first section of this thesis offers a political conception of catharsis that theorizes the receiver of narratives as programmable and guidable towards attitudes and postures. This conception leads directly to a machinic definition of the narrative and the concept of machinic enslavement. These concepts conceive of human subjectivity as engaged in processes of networking where it loses fragments of its unicity. The third chapter of this thesis theorizes Deleuze's society of control and its conceptual successors, surveillance capitalism and ectosubjectivity. Both these concepts attempt to theorize the reigning regime of power of the twenty-first century, based on personal data and the standardization of the human psyche. Finally, the fourth and final chapter of this research analyzes the notion of truth as described by Michel Foucault in The Courage of Truth. In the Greek notion of parrhēsia, and especially in its platonic development, Foucault identifies the homogeneity of a truth system based on a hierarchization of ethics. The reversal of this system by the Cynics into an assumed bestiality is crucial to this thesis as it opens new territories of existence and truth. In sum, the Cynic reversal permits us to conceive of a free existence, outside of a regime of truth that desubjectivates and homogenizes

    Vocal emotions on the brain: the role of acoustic parameters and musicality

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    The human voice is a powerful transmitter of emotions. This dissertation addresses three main gaps in the field of vocal emotion perception. The first is the quantification of the relative contribution of fundamental frequency (F0) and timbre cues to the perception of different emotions and their associated electrophysiological correlates. Using parameter-specific voice morphing, the results show that both F0 and timbre carry unique information that allow emotional inferences, although F0 seems to be relatively more important overall. The electrophysiological data revealed F0- and timbre-specific modulations in several ERP components, such as the P200 and the N400. Second, it was explored how musicality affects the processing of emotional voice cues, by providing a review on the literature linking musicality to emotion perception and subsequently showing that musicians have a benefit in vocal emotion perception compared to non-musicians. The present data offer original insight into the special role of pitch cues: musicians outperformed non-musicians when emotions were expressed by the pitch contour only, but not when they were expressed by vocal timbre. Although the electrophysiological patterns were less conclusive, they imply that musicality may modulate brain responses to vocal emotions. Third, this work provides a critical reflection on parameter-specific voice morphing and its suitability to study the processing of vocal emotions. Distortions in voice naturalness resulting from extreme acoustic manipulations were identified as one of the major threats to the ecological validity of the stimulus material produced with this technique. However, the results suggested that while voice morphing does affect the perceived naturalness of stimuli, behavioral measures of emotion perception were found to be remarkably robust against these distortions. Thus, the present data advocate parameter-specific voice morphing as a valid tool for vocal emotional research

    Afektiivsete individuaalsete erinevuste psühholoogiliste mehhanismide uurimine EEG korrelaatidega

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    Väitekirja elektrooniline versioon ei sisalda publikatsiooneAfektiivsed individuaalsed erinevused on võrdlemisi stabiilsed kalduvused kogeda teatud afektiivseid seisundeid. Afektiivsete individuaalsete erinevuste psühholoogiliste mehhanismide kaardistamine võib anda väärtuslikku infot nende seostest vaimse tervisega. Käesolev väitekiri pakub varasemale kirjandusele tuginedes välja teoreetilise mudeli antud mehhanismide mõtestamiseks ja uurimiseks. Konstrukti-Protsessi-Konteksti (KPK) mudeli kohaselt avalduvad psühholoogilised mehhanismid uuritava individuaalse erinevuse konstrukti, seda iseloomustava afektiivse protsessi eripära ning viimase avaldumist mõjutavate kontekstuaalsete tegurite kokkupuutealal. Väitekirja empiirilised tööd rakendavad KPK mudelit erinevate afektiivsete individuaalsete erinevuste mehhanismide uurimiseks elektroentsefalograafia (EEG) abil. Töid ühendab keskendumine mehhanismidele, mis seisnevad lähenemis- ja vältimismotivatsiooni või motivatsioonilise tähelepanu eripärades. Uuringud I ja III täpsustavad antud protsesside hindamise metodoloogilisi aspekte. Uuringu II tulemused osutavad sellele, et kõrge Neurootilisusega (negatiivse afektiivsuse ja psüühikahäirete riskiga seotud isiksuseomadus) inimesi iseloomustab vältimismotivatsiooni kogemine vastusena pilkkontaktiga mudeldatud neutraalsele sotsiaalsele tähelepanule. Uuring IV demonstreerib, kuidas hõivatus kehakaalust ja välimusest (oluline söömishäirete riskitegur) on seotud ülemäärase tähelepanuga enda kehasuuruse muutustele ja puuduliku tähelepanuga kellegi teise kehasuuruse muutustele. Uuring V näitab, et teadvelolekut (arendatav kalduvus käesoleva kogemuse hinnanguvabaks teadvustamiseks, mis on seotud madalama emotsionaalse reaktiivsuse ja parema vaimse tervisega) iseloomustab kiirem negatiivse informatsiooni eelistöötluse vähenemine ehk tõhusam afektiivne adaptatsioon. Väitekirja uuringutest järeldub, et KPK mudeli rakendamine võib aidata tuvastada väga erinevate afektiivsete individuaalsete erinevuste võimalikke psühholoogilisi mehhanisme.Affective individual differences are relatively stable tendencies to experience certain patterns of affective states. Clarifying the psychological mechanisms of affective individual differences can offer valuable insights into mental health and illness. Building on previous work, the current dissertation proposed the Construct-Process-Context (CPC) framework as a conceptual tool for studying these mechanisms. The CPC framework suggests that affective individual differences involve biases in specific affective processes that arise in specific contexts. The empirical studies of the dissertation applied the CPC framework to electroencephalography (EEG) based investigation of the mechanisms of affective individual differences that involve either approach-avoidance motivation or motivated attention. Studies I and III clarified open methodological questions to inform the design and interpretation of individual difference studies. Study II demonstrated that high levels of Neuroticism, a personality dimension that is characterized by negative affectivity and elevated risk for psychopathology, may be related to the activation of avoidance tendencies in response to another person’s directed attention (i.e., eye contact) during a neutral social encounter. Study IV demonstrated that high preoccupation with body image, which is a risk factor for eating disorders, may involve attentional over-prioritization of own body size and under-prioritization of peer body size. Finally, Study V demonstrated that cultivated mindfulness, a trainable tendency to be aware of and nonjudgmental toward one’s experiences that has been related to reduced affective reactivity and better mental health, is characterized by improved affective adaptation as indicated by initial increase and subsequent decrease in the salience of negative stimuli. It was concluded that the CPC framework may be helpful for clarifying the psychological mechanisms of very different affective individual difference constructs

    From the Cell to the Brain –Fear and Anxiety across the Levels of Neuroscience

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    The four studies presented in this thesis independently provided support for a dynamic multilevel account for anxiety-related phenomena (see Table 2). Study 1 showed how medial prefrontal cortex activity (i.e., Structure Level) measured with EEG was related to heart rate (PNS Level) and provided some evidence that this association was dynamically linked to trait anxiety: in conditions of negative but not positive feedback did trait anxiety increase the link between cortical and cardiac activity. This modulation is consistent with the functional definition of anxiety given that negative but not positive feedback is normally associated with increased danger in the future. Study 2 showed how dopaminergic genes (Molecule Level) and manipulations of dopamine (Synapse Level) presumably affected network states (Network Level), which then influenced brain activity at the AMC (Structure Level) and error-related behavior (Whole System Level). The unexpected finding that trait-anxiety was not related to error monitoring in that study can be explained post hoc by task characteristics (Olvet & Hajcak, 2009), again suggesting that some patterns of multilevel interactions are dynamically linked to anxiety. Study 3 tested individuals with GAD (manifest at the Whole System Level) using a neuropsychological test designed to measure future-orientation in patients with damage of the ventromedial prefrontal cortex (Structure Level) and resulting impairments in neurovisceral connectivity (Bechara et al., 1997) thus affecting the CNS and PNS-Levels. Consistent with (a) the assumed future-orientation of anxiety and (b) increased neurovisceral connectivity in anxiety (Study 1) individuals with GAD performed better in the IGT than non-anxious control participants. Finally, Study 4 manipulated intracellular signalling cascades (Molecule Level), thereby modulating synaptic learning and extinction learning (Synapse Level), which then affected fear-related reflex potentiation (CNS-Level and Whole Systems Level). In contrast to prior studies that found improved extinction learning of hippocampus-dependent fear memory (e.g., fear conditioned to a place), Study 4 found that rolipram disturbed extinction learning of presumably hippocampus independent fear-memory (e.g., fear conditioned to a sound). Together with these other studies, Study 4 thus provides further evidence that situational characteristics (place vs. sound as cue for present danger) may influence various levels (including the Molecule Level) with regard to fear processing. As can be seen in Table 2, some studies covered different levels than others. Of course, the herein proposed subdivision into eight levels of organization should be seen as a flexible framework used for illustrating the multilevel perspective rather than as a rigid model. Future research may uncover that much more levels of organization are needed to explain certain phenomena, and there may also be cases when good predictions can be made based on fewer than eight levels. However, Table 2 also shows that guesses for most empty cells can be made based on existing theories and research findings. A critical exception may be the network level, and it has been noted by others that this level is underrepresented in cognitive neuroscience research. However, the network level may be particularly critical for linking what we know about substances, cells, synapses and neurons (mostly based on in vitro work) to what we know about anxiety relevant structures (based on neuroimaging, EEG and lesion studies). From this perspective, future studies that include the neural network levels when investigating danger-reduction phenomena may be indispensable stations for achieving a wholistic understanding of fear and anxiety

    A Review on the Computational Methods for Emotional State Estimation from the Human EEG

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    A growing number of affective computing researches recently developed a computer system that can recognize an emotional state of the human user to establish affective human-computer interactions. Various measures have been used to estimate emotional states, including self-report, startle response, behavioral response, autonomic measurement, and neurophysiologic measurement. Among them, inferring emotional states from electroencephalography (EEG) has received considerable attention as EEG could directly reflect emotional states with relatively low costs and simplicity. Yet, EEG-based emotional state estimation requires well-designed computational methods to extract information from complex and noisy multichannel EEG data. In this paper, we review the computational methods that have been developed to deduct EEG indices of emotion, to extract emotion-related features, or to classify EEG signals into one of many emotional states. We also propose using sequential Bayesian inference to estimate the continuous emotional state in real time. We present current challenges for building an EEG-based emotion recognition system and suggest some future directions.open

    Time to Face Language: Embodied Mechanisms Underpin the Inception of Face-Related Meanings in the Human Brain

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    In construing meaning, the brain recruits multimodal (conceptual) systems and embodied (modality-specific) mechanisms. Yet, no consensus exists on how crucial the latter are for the inception of semantic distinctions. To address this issue, we combined electroencephalographic (EEG) and intracranial EEG (iEEG) to examine when nouns denoting facial body parts (FBPs) and nonFBPs are discriminated in face-processing and multimodal networks. First, FBP words increased N170 amplitude (a hallmark of early facial processing). Second, they triggered fast (~100 ms) activity boosts within the face-processing network, alongside later (~275 ms) effects in multimodal circuits. Third, iEEG recordings from face-processing hubs allowed decoding ~80% of items before 200 ms, while classification based on multimodal-network activity only surpassed ~70% after 250 ms. Finally, EEG and iEEG connectivity between both networks proved greater in early (0-200 ms) than later (200-400 ms) windows. Collectively, our findings indicate that, at least for some lexico-semantic categories, meaning is construed through fast reenactments of modality-specific experience.Fil: García, Adolfo Martín. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Cuyo. Facultad de Educación Elemental y Especial; Argentina. Universidad de San Andrés; Argentina. Universidad de Santiago de Chile; Chile. University of California; Estados UnidosFil: Hesse Rizzi, Eugenia Fátima. Universidad de San Andrés; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt | Instituto de Neurología Cognitiva. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt | Fundación Favaloro. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt; ArgentinaFil: Birba, Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de San Andrés; ArgentinaFil: Gonzalez Adolfi, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt | Instituto de Neurología Cognitiva. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt | Fundación Favaloro. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt; ArgentinaFil: Mikulan, Ezequiel Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Neurociencia Cognitiva. Fundación Favaloro. Instituto de Neurociencia Cognitiva; Argentina. Università degli Studi di Milano; ItaliaFil: Martorell Caro, Miguel Angel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt | Instituto de Neurología Cognitiva. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt | Fundación Favaloro. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt; ArgentinaFil: Petroni, Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigación en Ciencias de la Computación. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigación en Ciencias de la Computación; ArgentinaFil: Bekinchstein, Tristán. University of Cambridge; Reino UnidoFil: García, María del Carmen. Hospital Italiano; ArgentinaFil: Silva, Walter. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Hospital Italiano; ArgentinaFil: Ciraolo, Carlos. Hospital Italiano; ArgentinaFil: Vaucheret Paz, Esteban Fabian. Hospital Italiano; ArgentinaFil: Sedeño, Lucas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt | Instituto de Neurología Cognitiva. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt | Fundación Favaloro. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt; ArgentinaFil: Ibañez, Agustin Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt | Instituto de Neurología Cognitiva. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt | Fundación Favaloro. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt; Argentina. Universidad de San Andrés; Argentina. University of California; Estados Unidos. Universidad Adolfo Ibañez; Chil

    Pain as Feedback for Bionic Limbs

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    Abstract: This paper looks at advancements made in the area of thought controlled mechanical prosthesis that are being developed for amputees in order for them to regain mobility. It focuses on the brain-machine interface which is hardware and software that is used to control mechanical prosthesis or bionic limbs by sending and receiving signals between the prosthetic and the users mind. There is signaling feedback from the prosthesis to the user that indicates how much pressure is being applied to an object that is being grasped for instance. This paper explores the notion of the value of pain as a warning in the form of artificial feedback to help prevent damage and death to people and posits that pain should be included in the feedback loop so that when, for example, an artificial hand is in imminent danger of being burned the wearer is alerted

    Zur Plastizität von sozio-emotionalen Kompetenzen auf Verhaltens- und Gehirnebene: Eine EEG-begleitete Trainingsstudie bei Vorschulkindern mittels des computergestützten Trainingsprogramms Zirkus Empathico

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    Die Förderung funktionaler sozio-emotionaler Kompetenz in der Vorschulzeit (Altersspanne 3 bis 6 Jahre) ist von entscheidender Bedeutung, um der Entstehung psychischer Störungen vorzubeugen. Bislang gibt es nur wenige Studien, die die Auswirkungen digitaler Trainings auf die sozio-emotionale Entwicklung von Vorschulkindern untersuchen. Ebenso liefert die Forschung umfangreiche Informationen über typisches sozio-emotionales Verhalten bei Vorschulkindern, während weniger darüber bekannt ist, wie das Gehirn diese Funktionen umsetzt. Ziel der Dissertation war es daher, grundlegende und komplexe Aspekte der sozio-emotionalen Kompetenz von Vorschulkindern zu untersuchen, indem ihre Reife und Trainierbarkeit mit Verhaltens- und neuronalen Maßen erfasst wurden. In den Studien 1 und 2 wurden ereigniskorrelierte Potenziale und die Fast Periodic Visual Stimulation Methode eingesetzt, um neuronale Mechanismen der Emotionserkennung zu quantifizieren. Beide Studien ergaben das Vorhandensein grundlegender Mechanismen der Emotionserkennung in dieser Altersgruppe. Darüber hinaus zeigten Vorschulkinder einen Verarbeitungsvorteil von fröhlichen gegenüber ärgerlichen oder neutralen Gesichtern. Studie 3 untersuchte die Trainierbarkeit sozio-emotionaler Kompetenz anhand des digitalen Trainings Zirkus Empathico. Die Zirkus-Empathico-Gruppe zeigte im Vergleich zur Kontrollgruppe einen Anstieg sowohl der grundlegenden als auch der komplexen sozio-emotionalen Kompetenzen. Darüber hinaus ergab sich für die Zirkus-Empathico-Gruppe auf der neuronalen Ebene einen Verarbeitungsvorteil für fröhliche Gesichter. Zusammenfassend zeigt sich ein erheblicher Nutzen neuronaler Marker für das Verständnis von Mechanismen, welchen der Emotionserkennung von Vorschulkindern zugrunde liegen. Die vielversprechende Evidenz für die Wirksamkeit eines digitalen sozio-emotionalen Kompetenztrainings ermöglicht darüber hinaus weitere Überlegungen zur Nachhaltigkeit der Effekte sowie der gesellschaftlichen Bedeutung.Promoting functional socio-emotional competence in the preschool years (age range 3 to 6 years) is crucial to prevent the development of psychological disorders. To date, there are few studies examining the effects of digital training on the socio-emotional development of preschool children. Similarly, research provides extensive information on typical socio-emotional behaviors in preschool children, while less is known about how the brain implements these functions. Therefore, the goal of this dissertation was to examine fundamental and complex aspects of preschoolers' socio-emotional competence by assessing their maturity and trainability with behavioral and neuronal measures. Studies 1 and 2 used event-related potentials and the Fast Periodic Visual Stimulation method to quantify neural mechanisms of emotion recognition. Both studies revealed the presence of basic emotion recognition mechanisms in this age group. In addition, preschoolers showed a processing advantage of happy over angry or neutral faces. Study 3 investigated the trainability of socio-emotional competence using the digital training Zirkus Empathico. The Zirkus Empathico group showed an increase in both basic and complex socio-emotional competencies compared to the control group. In addition, the Zirkus Empathico group showed a processing advantage for happy faces at the neuronal level. In summary, neuronal markers show considerable utility for understanding mechanisms underlying emotion recognition in preschool children. The promising evidence for the efficacy of digital socio-emotional skills training also allows further consideration of the sustainability of the effects as well as the societal significance
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