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Online speech processing imposes significant computational demands on the listening brain, the underlying mechanisms of which remain poorly understood. Here, we exploit the perceptual "pop-out" phenomenon (i.e. the dramatic improvement of speech intelligibility after receiving information about speech content) to investigate the neurophysiological effects of prior expectations on degraded speech comprehension. We recorded electroencephalography (EEG) and pupillometry from 21 adults while they rated the clarity of noise-vocoded and sine-wave synthesized sentences. Pop-out was reliably elicited following visual presentation of the corresponding written sentence, but not following incongruent or neutral text. Pop-out was associated with improved reconstruction of the acoustic stimulus envelope from low-frequency EEG activity, implying that improvements in perceptual clarity were mediated via top-down signals that enhanced the quality of cortical speech representations. Spectral analysis further revealed that pop-out was accompanied by a reduction in theta-band power, consistent with predictive coding accounts of acoustic filling-in and incremental sentence processing. Moreover, delta-band power, alpha-band power, and pupil diameter were all increased following the provision of any written sentence information, irrespective of content. Together, these findings reveal distinctive profiles of neurophysiological activity that differentiate the content-specific processes associated with degraded speech comprehension from the context-specific processes invoked under adverse listening conditions.
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Motivação , Percepção da Fala , Ruído , Eletroencefalografia , Estimulação Acústica , Inteligibilidade da Fala/fisiologia , Percepção da Fala/fisiologiaRESUMO
Karl Friston's free-energy principle casts agents as self-evidencing through active inference. This implies that decision-making, planning and information-seeking are, in a generic sense, 'wishful'. We take an interdisciplinary perspective on this perplexing aspect of the free-energy principle and unpack the epistemological implications of wishful thinking under the free-energy principle. We use this epistemic framing to discuss the emergence of biases for self-evidencing agents. In particular, we argue that this elucidates an optimism bias as a foundational tenet of self-evidencing. We allude to a historical precursor to some of these themes, interestingly found in Machiavelli's oeuvre, to contextualise the universal optimism of the free-energy principle.
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BACKGROUND: People often feel urges to engage in activities that violate pandemic public health guidelines. Research on these urges has been reliant on measures of typical behaviour, which fail to capture these urges as they unfold. Guideline adherence could be improved through interventions, but few methods allow for ecologically valid observation of the range of behaviours that pandemic guidelines prescribe. METHODS: In this preregistered parallel randomised trial, 95 participants aged 18-65 from the UK were assigned to three groups using blinded block randomisation, and engaged in episodic future thinking (n = 33), compassion exercises (n = 31), or a control procedure (n = 31). Following an ecological momentary assessment procedure, participants report on the intensity of their occurrent urges (min. 1, max. 10) and their ability to control them. The study further investigates whether, and through which mechanism, state impulsivity and vaccine attitudes affect guideline adherence. RESULTS: Episodic future thinking (b = -1.80) and compassion exercises (b = -1.45) reduced the intensity of urges. State impulsivity is associated with stronger urges, but we found no evidence that vaccine hesitancy predicts lesser self-control. CONCLUSIONS: We conclude that episodic future thinking exercises and compassion training may be used to decrease non-compliance urges of individuals who are an acute public health risk for the community, such as those in voluntary isolation.
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Empatia , Saúde Pública , Humanos , Exercício Físico , Terapia por Exercício , Cooperação do PacienteRESUMO
OBJECTIVE: Borderline Personality Disorder (BPD) diagnosis comprises several constellations of trait, neurocognitive, and psychosocial alterations. Dimensional models of psychopathology provide new opportunities to parse heterogeneity and create a stronger interface between individual characterization and psychosocial outcomes. However, dimensional models have focused on either traits or neurocognitive features, lacking integration to capture the multifaceted nature of BPD. METHOD: We assessed 100 participants with BPD using a combination of tools stemming from trait (Alternative Model for Personality Disorders) and neurocognitive models (Research Domain Criteria; RDoC) to examine if trait-derived subgroups display distinctive social-processing and psychosocial profiles. We used two complementary analytical approaches: person-centered (k-means clustering) and construct-based (multiple factor analysis). RESULTS: Our person-centered approach identified four subgroups with separable internalizing, detached, externalizing, and low psychopathology trait profiles. These profiles revealed distinctive patterns of affiliation, emotion recognition and mentalization performance in RDoC tasks, and psychosocial measures of quality of life and social connectedness. RDoC-based measures showed close construct proximity with negative affectivity, disinhibition, and antagonism trait domains, relative to the detachment domain, which had close proximity with self-knowledge. CONCLUSIONS: Altogether, findings support consilience between trait-based and neurobiological frameworks and suggest that trait models are useful to parse BPD heterogeneity leading to unique social functioning profiles.
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Transtorno da Personalidade Borderline , Humanos , Qualidade de Vida , Transtornos da Personalidade , Psicopatologia , Interação SocialRESUMO
The question how the brain distinguishes between information about self and others is of fundamental interest to both philosophy and neuroscience. In this functional magnetic resonance imaging (fMRI) study, we sought to distinguish the neural substrates of representing a full-body movement as one's movement and as someone else's movement. Participants performed a delayed match-to-sample working memory task where a retained full-body movement (displayed using point-light walkers) was arbitrarily labeled as one's own movement or as performed by someone else. By using arbitrary associations we aimed to address a limitation of previous studies, namely that our own movements are more familiar to us than movements of other people. A searchlight multivariate decoding analysis was used to test where information about types of movement and about self-association was coded. Movement specific activation patterns were found in a network of regions also involved in perceptual processing of movement stimuli, however not in early sensory regions. Information about whether a memorized movement was associated with the self or with another person was found to be coded by activity in the left middle frontal gyrus (MFG), left inferior frontal gyrus (IFG), bilateral supplementary motor area, and (at reduced threshold) in the left temporoparietal junction (TPJ). These areas are frequently reported as involved in action understanding (IFG, MFG) and domain-general self/other distinction (TPJ). Finally, in univariate analysis we found that selecting a self-associated movement for retention was related to increased activity in the ventral medial prefrontal cortex.
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Memória de Curto Prazo , Córtex Motor , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Mapeamento Encefálico , Humanos , Imageamento por Ressonância Magnética/métodos , Memória de Curto Prazo/fisiologiaRESUMO
Perception likely results from the interplay between sensory information and top-down signals. In this electroencephalography (EEG) study, we utilised the hierarchical frequency tagging (HFT) method to examine how such integration is modulated by expectation and attention. Using intermodulation (IM) components as a measure of nonlinear signal integration, we show in three different experiments that both expectation and attention enhance integration between top-down and bottom-up signals. Based on a multispectral phase coherence (MSPC) measure, we present two direct physiological measures to demonstrate the distinct yet related mechanisms of expectation and attention, which would not have been possible using other amplitude-based measures. Our results link expectation to the modulation of descending signals and to the integration of top-down and bottom-up information at lower levels of the visual hierarchy. Meanwhile, the results link attention to the modulation of ascending signals and to the integration of information at higher levels of the visual hierarchy. These results are consistent with the predictive coding account of perception.
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Motivação/fisiologia , Percepção/fisiologia , Adolescente , Adulto , Atenção/fisiologia , Percepção Auditiva/fisiologia , Mapeamento Encefálico , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Percepção Visual/fisiologiaRESUMO
OBJECTIVE: Social processing (SP) deficits manifest across numerous mental disorders. However, this research has been plagued by heterogeneity and a piecemeal approach whereby skills are examined in isolation rather than as part of an integrated cognitive system. Here, we combined two dimensional frameworks of psychopathology to address these limitations. METHOD: We utilized the Alternative Model for Personality Disorders (AMPD) to distill trait-related heterogeneity within a community sample (n = 200), and the Research Domain Criteria (RDoC) 'Systems for Social Processes' to comprehensively assess SP. We first applied latent class analyses (LCA) to derive AMPD-based groups and subsequently contrasted the performance of these groups on a SP test battery that we developed to align with the RDoC SP constructs. RESULTS: Our LCA yielded four distinct subgroups. The recognizable trait profiles and psychopathological symptoms of these classes suggested they were clinically meaningful. The subgroups differed in their SP profiles: one displayed deficits regarding the self, a second displayed deficits in understanding others, a third displayed more severe deficits including affiliation problems, whilst the fourth showed normal performance. CONCLUSIONS: Our results support the link between clusters of maladaptive personality traits and distinctive profiles of SP deficits, which may inform research on disorders involving SP dysfunctions.
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Transtornos da Personalidade , Psicopatologia , Humanos , Análise de Classes Latentes , Personalidade , Transtornos da Personalidade/psicologia , Inventário de PersonalidadeRESUMO
We challenge the authors' view that Markov blankets are illicitly reified when used to describe organismic boundaries. We do this both on general methodological grounds, where we appeal to a form of structural realism derived from Bayesian cognitive science to dissolve the problem, and by rebutting specific arguments in the target article.
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Dissidências e Disputas , Teorema de Bayes , HumanosRESUMO
Perception results from complex interactions among sensory and cognitive processes across hierarchical levels in the brain. Intermodulation (IM) components, used in frequency tagging neuroimaging designs, have emerged as a promising direct measure of such neural interactions. IMs have initially been used in electroencephalography (EEG) to investigate low-level visual processing. In a more recent trend, IMs in EEG and other neuroimaging methods are being used to shed light on mechanisms of mid- and high-level perceptual processes, including the involvement of cognitive functions such as attention and expectation. Here, we provide an account of various mechanisms that may give rise to IMs in neuroimaging data, and what these IMs may look like. We discuss methodologies that can be implemented for different uses of IMs and we demonstrate how IMs can provide insights into the existence, the degree and the type of neural integration mechanisms at hand. We then review a range of recent studies exploiting IMs in visual perception research, placing an emphasis on high-level vision and the influence of awareness and cognition on visual processing. We conclude by suggesting future directions that can enhance the benefits of IM-methodology in perception research.
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Córtex Cerebral/fisiologia , Eletroencefalografia/métodos , Potenciais Evocados Visuais/fisiologia , Magnetoencefalografia/métodos , Percepção Visual/fisiologia , HumanosRESUMO
The purpose of this review was to integrate leading paradigms in psychology and neuroscience with a theory of the embodied, situated human brain, called the Hierarchically Mechanistic Mind (HMM). The HMM describes the brain as a complex adaptive system that functions to minimize the entropy of our sensory and physical states via action-perception cycles generated by hierarchical neural dynamics. First, we review the extant literature on the hierarchical structure of the brain. Next, we derive the HMM from a broader evolutionary systems theory that explains neural structure and function in terms of dynamic interactions across four nested levels of biological causation (i.e., adaptation, phylogeny, ontogeny, and mechanism). We then describe how the HMM aligns with a global brain theory in neuroscience called the free-energy principle, leveraging this theory to mathematically formulate neural dynamics across hierarchical spatiotemporal scales. We conclude by exploring the implications of the HMM for psychological inquiry.
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Evolução Biológica , Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Cognição/fisiologia , Teoria de Sistemas , Humanos , Modelos Neurológicos , Teoria PsicológicaRESUMO
Time judgement and time experience are distinct elements of time perception. It is known that time experience tends to be slow, or dilated, when depressed, but there is less certainty or clarity concerning how depression affects time judgement. Here, we use a Bayesian Prediction Error Minimisation (PEM) framework called 'distrusting the present' as an explanatory and predictive model of both aspects of time perception. An interval production task was designed to probe and modulate the relationship between time perception and depression. Results showed that hopelessness, a symptom of severe depression, was associated with the ordering of interval lengths, reduced overall error, and dilated time experience. We propose that 'distrusting the future' is accompanied by 'trusting the present', leading to the experiences of time dilation when depressed or hopeless. Evidence was also found to support a relative difference model of how hopelessness dilates, and arousal accelerates, the rate of experienced time.
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Nível de Alerta/fisiologia , Sistema Nervoso Autônomo/fisiopatologia , Transtorno Depressivo/fisiopatologia , Esperança/fisiologia , Percepção do Tempo/fisiologia , Adolescente , Adulto , Teorema de Bayes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: Individuals with cocaine use disorder (CUD) often display behaviours that are paradoxically misaligned with their situation. Typical examples include poor treatment motivation and inconsistent self-reported craving. These behaviours may reflect impairments in the awareness of one's own behaviour. OBJECTIVES: We examined whether impaired self-awareness of addiction-related frontostriatal dysfunction (i.e., symptoms of apathy, disinhibition, and executive dysfunction) was associated with treatment motivation and craving. METHODS: Sixty-five outpatients with CUD (57 male) and their informants (those who knew the patient well) completed parallel self and informant versions of the Frontal Systems Behaviour Scale. Self-awareness was indexed through the discrepancy between self and informant scores in the three sub-scales; apathy, disinhibition and executive dysfunction. The University Rhode Island Change Assessment Scale assessed treatment motivation. Self-reported craving was assessed using a visual analogue scale. Multiple linear regression models examined associations between self-awareness and treatment motivation and craving, adjusting for sociodemographic factors and lifetime drug use. RESULTS: We found an inverse relationship between self-awareness of symptoms of disinhibition and treatment motivation maintenance. Although impaired awareness of disinhibition was also correlated with craving, this association was not significant after adjusting for sociodemographic factors and drug use. The apathy and executive dysfunction awareness scores were not associated with treatment motivation or craving. CONCLUSION: We show that people with lower insight into their disinhibition problems (e.g., impulsivity, mood instability) have more problems maintaining motivation when initiating treatment. Findings suggest that self-awareness interventions could be useful to prevent premature treatment dropout and improve addiction treatment outcomes.
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Comportamento Aditivo/psicologia , Transtornos Relacionados ao Uso de Cocaína/psicologia , Motivação , Autoimagem , Adulto , Transtornos Relacionados ao Uso de Cocaína/terapia , Fissura , Função Executiva , Feminino , Humanos , Masculino , Pacientes Ambulatoriais , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , AutorrelatoRESUMO
This article examines the serious shortcomings that characterize the current taxonomy of postcomatose disorders of consciousness (DoC), and it provides guidelines for how an improved DoC taxonomy might be developed. In particular, it is argued that behavioral criteria for the application of DoC categories should be supplemented with brain-based criteria (eg, information derived from electroencephalography and functional magnetic resonance imaging), and that the categorical framework that currently characterizes DoC should be replaced by a multidimensional framework that better captures the performance of patients across a range of cognitive and behavioural tasks. Ann Neurol 2017;82:866-872.
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Encéfalo/fisiopatologia , Transtornos da Consciência/classificação , Transtornos da Consciência/fisiopatologia , Estado de Consciência/fisiologia , Classificação , Transtornos da Consciência/diagnóstico , Humanos , Metacognição/fisiologia , Volição/fisiologiaRESUMO
INTRODUCTION: "Body swapping" illusions have been used to explore factors contributing to the experience of "owning" an artificial body. Preliminary research indicated that those people diagnosed with schizophrenia experience more vivid illusions of this kind than do "normal" individuals. OBJECTIVES: Here, we explored whether participants who rated themselves "high" on the cognitive-perceptual factor of the Schizotypal Personality Questionnaire (SPQ) experienced a more compelling sense of immersion in a variation of the body swapping illusion: The Barbie Doll Illusion. We also hypothesised that these individuals would experience a change in size perception when immersed in the illusion. METHOD: Forty-four participants wore a pair of Head-Mounted Display goggles connected to a video-camera, and thus a doll's body replaced their own body in their visual field. In two conditions, touch was either applied synchronously or asynchronously to the doll's and each participant's leg. After each condition, participants filled out a questionnaire relating to their experience in the illusion. When both conditions were completed, they filled out the SPQ. RESULTS: Our first hypothesis was confirmed, which suggested that people with higher cognitive-perceptual SPQ scores do indeed experience a more compelling Barbie Doll Illusion; however, our second hypothesis was not supported. CONCLUSION: Our study demonstrated, for the first time, that proneness to the positive and interpersonal factors of schizotypy in a normal population is sufficient to produce a compelling sense of swapping bodies.
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Imagem Corporal/psicologia , Ilusões/psicologia , Transtorno da Personalidade Esquizotípica/psicologia , Percepção de Tamanho , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Transtorno da Personalidade Esquizotípica/diagnóstico , Adulto JovemRESUMO
I discuss top-down modulation of perception in terms of a variable Bayesian learning rate, revealing a wide range of prior hierarchical expectations that can modulate perception. I then switch to the prediction error minimization framework and seek to conceive cognitive penetration specifically as prediction error minimization deviations from a variable Bayesian learning rate. This approach retains cognitive penetration as a category somewhat distinct from other top-down effects, and carves a reasonable route between penetrability and impenetrability. It prevents rampant, relativistic cognitive penetration of perception and yet is consistent with the continuity of cognition and perception.
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Teorema de Bayes , Cognição/fisiologia , Aprendizagem/fisiologia , Percepção/fisiologia , Teoria Psicológica , HumanosAssuntos
Transtorno Autístico , Big Data , Encéfalo , Feminino , Humanos , Masculino , Caracteres SexuaisRESUMO
Recent predictive processing accounts of perception and action point towards a key challenge for the nervous system in dynamically optimizing the balance between incoming sensory information and existing expectations regarding the state of the environment. Here, we report differences in the influence of the preceding sensory context on motor function, varying with respect to both clinical and subclinical features of autism spectrum disorder (ASD). Reach-to-grasp movements were recorded subsequent to an inactive period in which illusory ownership of a prosthetic limb was induced. We analysed the sub-components of reach trajectories derived using a minimum-jerk fitting procedure. Non-clinical adults low in autistic features showed disrupted movement execution following the illusion compared to a control condition. By contrast, individuals higher in autistic features (both those with ASD and non-clinical individuals high in autistic traits) showed reduced sensitivity to the presence of the illusion in their reaching movements while still exhibiting the typical perceptual effects of the illusion. Clinical individuals were distinct from non-clinical individuals scoring high in autistic features, however, in the early stages of movement. These results suggest that the influence of high-level representations of the environment differs between individuals, contributing to clinical and subclinical differences in motor performance that manifest in a contextual manner. As high-level representations of context help to explain fluctuations in sensory input over relatively longer time scales, more circumscribed sensitivity to prior or contextual information in autistic sensory processing could contribute more generally to reduced social comprehension, sensory impairments and a stronger desire for predictability and routine.
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Transtorno do Espectro Autista/fisiopatologia , Ilusões , Movimento , Adulto , Transtorno do Espectro Autista/psicologia , Feminino , Mãos , Força da Mão , Humanos , Masculino , Desempenho Psicomotor , Distúrbios Somatossensoriais/fisiopatologia , Adulto JovemRESUMO
The efference copy account of the tickle effect (i.e., our inability to tickle ourselves) predicts no tickle effect (i.e., an ability to tickle ourselves) when the trajectory of a tactile stimulus is perturbed relative to the associated movement, and there is evidence in support of this. The active inference account, however, predicts the tickle effect should survive trajectory perturbation. We test these accounts of the tickle effect under the hypothesis that previous findings are due to attentional modulation, and that the tickle effect will be found in a paradigm with no conscious attention directed to the trajectory perturbation. We thus expected to find support for active inference. Our first experiment confirms this hypothesis, while our second seeks to explain previous findings in terms of the modulation of the tickle sensation when there is awareness of, and different degrees of attention to, the spatial tactile and kinesthetic trajectories.
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Conscientização/fisiologia , Cinestesia/fisiologia , Percepção do Tato/fisiologia , Tato/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
The mental states of other people are components of the external world that modulate the activity of our sensory epithelia. Recent probabilistic frameworks that cast perception as unconscious inference on the external causes of sensory input can thus be expanded to enfold the brain's representation of others' mental states. This paper examines this subject in the context of the debate concerning the extent to which we have perceptual awareness of other minds. In particular, we suggest that the notion of perceptual presence helps to refine this debate: are others' mental states experienced as veridical qualities of the perceptual world around us? This experiential aspect of social cognition may be central to conditions such as autism spectrum disorder, where representations of others' mental states seem to be selectively compromised. Importantly, recent work ties perceptual presence to the counterfactual predictions of hierarchical generative models that are suggested to perform unconscious inference in the brain. This enables a characterisation of mental state representations in terms of their associated counterfactual predictions, allowing a distinction between spontaneous and explicit forms of mentalising within the framework of predictive processing. This leads to a hypothesis that social cognition in autism spectrum disorder is characterised by a diminished set of counterfactual predictions and the reduced perceptual presence of others' mental states.