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1.
Neuroimage ; 228: 117712, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33387630

RESUMO

In recent years, several ERP components have been identified as potential neural correlates of consciousness (NCC), including early negativities and late positivities. Based on experiments in the visual modality, it has recently been shown that awareness is often confounded with reporting it, possibly overestimating the NCC. It is unknown whether similar constraints also exist in the auditory modality. In order to address this gap, we presented spoken words in a sustained inattentional deafness paradigm. Electrophysiological responses were obtained in three physically identical experimental conditions that differed only with respect to the participants' instructions. Participants were either left uninformed or informed about the presence of spoken words while confronted with an auditory distractor task (U/I condition), informed about the words while exposed to the same task as before (I condition), or requested to respond to the now task-relevant speech stimuli (TR condition). After completion of the U/I condition, only informed participants reported awareness of the words. In ERPs, awareness of words in the U/I and I condition was accompanied by an anterior auditory awareness negativity (AAN). Only when stimuli were task-relevant, i.e., during the TR condition, late positivities emerged. Taken together, these results indicate that early negativities but not late positivities index awareness across sensory modalities. Thus, they provide evidence for a recurrent processing framework, which highlights the importance of early sensory processing in conscious perception.


Assuntos
Atenção/fisiologia , Percepção Auditiva/fisiologia , Conscientização/fisiologia , Estado de Consciência/fisiologia , Adolescente , Adulto , Encéfalo/fisiologia , Eletroencefalografia , Potenciais Evocados/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
2.
Neuroimage ; 228: 117681, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33359346

RESUMO

Sequences of repeating tones can be masked by other tones of different frequency. When these tone sequences are perceived, nevertheless, a prominent neural response in the auditory cortex is evoked by each tone of the sequence. When the targets are detected based on their isochrony, participants know that they are listening to the target once they detected it. To explore if the neural activity is more closely related to this detection task or to perceptual awareness, this magnetoencephalography (MEG) study used targets that could only be identified with cues provided after or before the masked target. In experiment 1, multiple mono-tone streams with jittered inter-stimulus interval were used, and the tone frequency of the target was indicated by a cue. Results showed no differential auditory cortex activity between hit and miss trials with post-stimulus cues. A late negative response for hit trials was only observed for pre-stimulus cues, suggesting a task-related component. Since experiment 1 provided no evidence for a link of a difference response with tone awareness, experiment 2 was planned to probe if detection of tone streams was linked to a difference response in auditory cortex. Random-tone sequences were presented in the presence of a multi-tone masker, and the sequence was repeated without masker thereafter. Results showed a prominent difference wave for hit compared to miss trials in experiment 2 evoked by targets in the presence of the masker. These results suggest that perceptual awareness of tone streams is linked to neural activity in auditory cortex.


Assuntos
Atenção/fisiologia , Córtex Auditivo/fisiologia , Conscientização/fisiologia , Mascaramento Perceptivo/fisiologia , /fisiologia , Adulto , Potenciais Evocados Auditivos/fisiologia , Feminino , Humanos , Magnetoencefalografia/métodos , Masculino , Adulto Jovem
3.
Nature ; 589(7842): 420-425, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33361808

RESUMO

Everyday tasks in social settings require humans to encode neural representations of not only their own spatial location, but also the location of other individuals within an environment. At present, the vast majority of what is known about neural representations of space for self and others stems from research in rodents and other non-human animals1-3. However, it is largely unknown how the human brain represents the location of others, and how aspects of human cognition may affect these location-encoding mechanisms. To address these questions, we examined individuals with chronically implanted electrodes while they carried out real-world spatial navigation and observation tasks. We report boundary-anchored neural representations in the medial temporal lobe that are modulated by one's own as well as another individual's spatial location. These representations depend on one's momentary cognitive state, and are strengthened when encoding of location is of higher behavioural relevance. Together, these results provide evidence for a common encoding mechanism in the human brain that represents the location of oneself and others in shared environments, and shed new light on the neural mechanisms that underlie spatial navigation and awareness of others in real-world scenarios.


Assuntos
Neurônios/fisiologia , Percepção Espacial/fisiologia , Navegação Espacial/fisiologia , Adulto , Conscientização/fisiologia , Relógios Biológicos , Cognição/fisiologia , Eletrodos Implantados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Lobo Temporal/fisiologia
4.
Trials ; 21(1): 1019, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33308290

RESUMO

BACKGROUND: Burnout is an occupational syndrome that leads to mental health problems, job turnover, and patient safety events. Those caring for critically ill patients are especially susceptible due to high patient mortality, long hours, and regular encounters with trauma and ethical issues. Interventions to prevent burnout in this population are needed. Preliminary studies suggest debriefing sessions may reduce burnout. This study aims to assess whether participation in regular debriefing can prevent burnout in intensive care unit (ICU) clinicians. METHODS: A randomized controlled trial will be conducted in two large academic medical centers. Two hundred ICU clinicians will be recruited with target enrollment of 100 physicians and 100 non-physicians (nurses, pharmacists, therapists). Participants must have worked in the ICU for the equivalent of at least 1 full time work week in the preceding 4 weeks. Enrolled subjects will be randomized to virtually attend biweekly debriefing sessions facilitated by a psychotherapist for 3 months or to a control arm without sessions. Our debriefs are modeled after Death Cafés, which are informal discussions focusing on death, dying, loss, grief, and illness. These sessions allow for reflection on distressing events and offer community and collaboration among hospital employees outside of work. The primary outcome is clinician burnout as measured by the Maslach Burnout Inventory (MBI) Score. Secondary outcomes include depression and anxiety, as measured by the Patient Health Questionnaire 8 (PHQ-8) and Generalized Anxiety Disorder 7-item scale (GAD-7), respectively. Questionnaires will be administered prior to the intervention, at 1 month, at 3 months, and at 6 months after enrollment. These values will be compared between groups temporally. Qualitative feedback will also be collected and analyzed. DISCUSSION: With ICU clinician burnout rates exceeding 50%, Death Café debriefing sessions may prove to be an effective tool to avert this debilitating syndrome. With COVID-19 limiting social interactions and overloading ICUs worldwide, the virtual administration of the Death Café for ICU clinicians provides an innovative strategy to potentially mitigate burnout in this vulnerable population. TRIAL REGISTRATION: ClinicalTrials.gov NCT04347811 . Registered on 15 April 2020.


Assuntos
Esgotamento Profissional/prevenção & controle , Unidades de Terapia Intensiva/estatística & dados numéricos , Estresse Ocupacional/psicologia , Assistência Terminal/psicologia , Ansiedade/diagnóstico , Ansiedade/epidemiologia , Conscientização/fisiologia , Esgotamento Profissional/epidemiologia , /virologia , Estudos de Casos e Controles , Comunicação , Estado Terminal/mortalidade , Estado Terminal/psicologia , Depressão/diagnóstico , Depressão/epidemiologia , Humanos , Estresse Ocupacional/epidemiologia , Questionário de Saúde do Paciente/estatística & dados numéricos , Segurança do Paciente/estatística & dados numéricos , Reorganização de Recursos Humanos/estatística & dados numéricos , Inquéritos e Questionários , Interface Usuário-Computador
5.
Sleep Med ; 74: 199-203, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32861011

RESUMO

OBJECTIVES: Sleep status can affect the body's immune status and mental health. This study aims to investigate the sleep status of Chinese residents during the outbreak of Coronavirus Disease 2019 (COVID-19) and to evaluate its related risk factors. METHODS: This research carried out a cross-sectional survey in February 2020 (during the COVID-19 outbreak) to investigate the sleep status of residents nationwide in the form of an online questionnaire. Of the 8151 respondents, 6437 were eventually included in the analysis. Logistic regression is applied to analyze the associated factors affecting residents' sleep quality. RESULTS: During the COVID-19 outbreak, the incidence of sleep disturbances in residents was 17.65%. Increased risk of sleep disturbances was found to be associated with older age, female gender, and poor self-reported health status. Moreover, the odds ratios (ORs) were 1.42 (95% CI: 1.1-2.64), 1.35 (95% CI: 1.16-1.59), 5.59 (95% CI: 4.32-7.23), respectively. Those residents who believed COVID-19 had caused a high number of deaths or who thought COVID-19 was not easy to cure were more likely to experience sleep disorders, and the ORs were 1.73 (95% CI: 1.43-2.09), 1.57 (95% CI: 1.29-1.91), respectively. Regular exercise was a protective factor for sleep disturbances, OR = 0.77 (95% CI: 0.63-0.93). CONCLUSIONS: During the outbreak of COVID-19, nearly one-fifth of participants had sleep disorders. It is necessary to pay more attention to people at high risk for sleep disturbances during the outbreak, adopt effective risk communication methods, enhance residents' rational understanding of COVID-19, and develop practical indoor exercise programs for general public to improve sleep quality.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/psicologia , Surtos de Doenças , Pneumonia Viral/epidemiologia , Pneumonia Viral/psicologia , Transtornos do Sono-Vigília/epidemiologia , Transtornos do Sono-Vigília/psicologia , Adulto , Conscientização/fisiologia , China/epidemiologia , Estudos Transversais , Surtos de Doenças/prevenção & controle , Exercício Físico/fisiologia , Exercício Físico/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Inquéritos e Questionários , Adulto Jovem
8.
Proc Natl Acad Sci U S A ; 117(27): 16055-16064, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32571942

RESUMO

Visual awareness is thought to result from integration of low- and high-level processing; instances of integration failure provide a crucial window into the cognitive and neural bases of awareness. We present neurophysiological evidence of complex cognitive processing in the absence of awareness, raising questions about the conditions necessary for visual awareness. We describe an individual with a neurodegenerative disease who exhibits impaired visual awareness for the digits 2 to 9, and stimuli presented in close proximity to these digits, due to perceptual distortion. We identified robust event-related potential responses indicating 1) face detection with the N170 component and 2) task-dependent target-word detection with the P3b component, despite no awareness of the presence of faces or target words. These data force us to reconsider the relationship between neural processing and visual awareness; even stimuli processed by a workspace-like cognitive system can remain inaccessible to awareness. We discuss how this finding challenges and constrains theories of visual awareness.


Assuntos
Cognição/fisiologia , Potenciais Evocados/fisiologia , Transtornos da Visão/metabolismo , Percepção Visual/fisiologia , Conscientização/fisiologia , Encéfalo/fisiologia , Eletroencefalografia , Potenciais Evocados Visuais/fisiologia , Face , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Neurodegenerativas , Estimulação Luminosa , Córtex Visual/fisiologia
9.
Epilepsia ; 61(6): 1156-1165, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32501547

RESUMO

OBJECTIVE: Dissociative traits represent a disturbance in selfhood that may predispose to, and trigger, functional seizures (FSs). The predictive representation and control of the internal physiological state of the body (interoception) are proposed to underpin the integrity of the sense of self ("minimal selfhood"). Therefore, discrepancies between objective and subjective aspects of interoception may relate to symptom expression in patients with FSs. Here, we tested whether individual differences in trait measures of interoception relate to dissociative symptoms, and whether state interoceptive deficits predict FS occurrence. METHODS: Forty-one participants with FSs and 30 controls completed questionnaire ratings of dissociation, and measures of (1) interoceptive accuracy (IA)-objective performance on heartbeat detection tasks; (2) trait interoceptive sensibility-subjective sensitivity to internal sensations (using the Porges Body Perception Questionnaire); and (3) state interoceptive sensibility-subjective trial-by-trial measures of confidence in heartbeat detection. Interoceptive trait prediction error (ITPE) was calculated from the discrepancy between IA and trait sensibility, and interoceptive state prediction error (ISPE) from the discrepancy between IA and state sensibility. RESULTS: Patients with FSs had significantly lower IA and greater trait interoceptive sensibility than healthy controls. ITPE was the strongest predictor of dissociation after controlling for trait anxiety and depression in a regression model. ISPE correlated significantly with FS frequency after controlling for state anxiety. SIGNIFICANCE: Patients with FSs have disturbances in interoceptive processing that predict both dissociative traits reflecting the disrupted integrity of self-representation, and the expression of FSs. These findings provide insight into the pathophysiology of functional neurological disorder, and could lead to novel diagnostic and therapeutic approaches.


Assuntos
Conscientização/fisiologia , Transtornos Dissociativos/diagnóstico , Transtornos Dissociativos/psicologia , Interocepção/fisiologia , Convulsões/diagnóstico , Convulsões/psicologia , Adulto , Ansiedade/diagnóstico , Ansiedade/fisiopatologia , Ansiedade/psicologia , Transtornos Dissociativos/fisiopatologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Testes Neuropsicológicos , Convulsões/fisiopatologia
10.
J Neurosci ; 40(25): 4925-4935, 2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32409620

RESUMO

To identify the neural correlates of perceptual awareness, researchers often compare the differences in neural activation between conditions in which an observer is or is not aware of a stimulus. While intuitive, this approach often contains a critical limitation: to link brain activity with perceptual awareness, observers traditionally report the contents of their perceptual experience. However, relying on observers' reports is problematic because it is difficult to know whether the neural responses being measured are associated with conscious perception or with postperceptual processes involved in the reporting task (e.g., working memory, decision-making). To address this issue, we combined a standard visual masking paradigm with a recently developed "no-report" paradigm in male/female human participants. In the visual masking paradigm, observers saw images of animals and objects that were visible or invisible, depending on their proximity to masks. Meanwhile, on half of the trials, observers reported the contents of their perceptual experience (i.e., report condition), while on the other half of trials they refrained from reporting about their experiences (i.e., no-report condition). We used electroencephalography to examine how visibility interacts with reporting by measuring the P3b event-related potential, one of the proposed canonical "signatures" of conscious processing. Overall, we found a robust P3b in the report condition, but no P3b whatsoever in the no-report condition. This finding suggests that the P3b itself is not a neural signature of conscious processing and highlights the importance of carefully distinguishing the neural correlates of perceptual awareness from postperceptual processing.SIGNIFICANCE STATEMENT What are the neural signatures that differentiate conscious and unconscious processing in the brain? Perhaps the most well established candidate signature is the P3b event-related potential, a late slow wave that appears when observers are aware of a stimulus, but disappears when a stimulus fails to reach awareness. Here, however, we found that the P3b does not track what observers are perceiving, but instead tracks what observers are reporting. When observers are aware of simple visual stimuli, the P3b is nowhere to be found unless observers are reporting the contents of their experience. These results challenge the well established notion of the P3b as a neural marker of awareness and highlight the need for new approaches to the neuroscience of consciousness.


Assuntos
Conscientização/fisiologia , Encéfalo/fisiologia , Potencial Evocado P300/fisiologia , Mascaramento Perceptivo/fisiologia , Percepção Visual/fisiologia , Adulto , Estado de Consciência/fisiologia , Eletroencefalografia , Feminino , Humanos , Masculino , Adulto Jovem
11.
J Stud Alcohol Drugs ; 81(2): 262-272, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32359057

RESUMO

OBJECTIVE: Alcohol labels are one strategy for communicating health information to consumers. This study tested the extent to which consumers recalled alcohol labels with national drinking guidelines and examined the impact of labels on awareness and knowledge of the guidelines. METHOD: A quasi-experimental study was conducted in two jurisdictions in northern Canada examining the impact of labels on the following outcomes: unprompted and prompted recall of the drinking guideline label message, awareness of the drinking guidelines, and knowledge of the daily and weekly recommended drink limits. The intervention site applied labels with national drinking guidelines, a cancer warning, and standard drink information to alcohol containers in its liquor store, whereas the comparison site did not apply these labels. In total, 2,049 cohort participants in both sites were recruited to complete surveys before and at two time points after the intervention. Changes in outcomes were examined using generalized estimating equations. RESULTS: After the intervention, unprompted and prompted recall of the drinking guideline label message increased more in the intervention versus comparison site (adjusted odds ratio [AOR] = 10.8, 95% CI [0.9, 127.6]; AOR = 7.0, 95% CI [3.3, 14.9], respectively). Awareness of the drinking guidelines increased 2.9 times more in the intervention versus comparison site (AOR = 2.9, 95% CI [2.0, 4.3]). In addition, knowledge of the daily and weekly drink limits increased 1.5 and 1.4 times more in the intervention versus comparison site, respectively (daily: AOR = 1.5, 95% CI [1.0, 2.1]; weekly: AOR = 1.4, 95% CI [1.0, 2.0]). CONCLUSIONS: Enhanced alcohol labels get noticed and may be an effective population-level strategy for increasing awareness and knowledge of national drinking guidelines.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/prevenção & controle , Bebidas Alcoólicas/efeitos adversos , Conhecimentos, Atitudes e Prática em Saúde , Neoplasias/prevenção & controle , Rotulagem de Produtos/normas , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Conscientização/fisiologia , Estudos de Coortes , Feminino , Guias como Assunto/normas , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Estudos Prospectivos , Inquéritos e Questionários , Yukon/epidemiologia
12.
Proc Natl Acad Sci U S A ; 117(19): 10575-10584, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32341167

RESUMO

Even though humans are mostly not aware of their heartbeats, several heartbeat-related effects have been reported to influence conscious perception. It is not clear whether these effects are distinct or related phenomena, or whether they are early sensory effects or late decisional processes. Combining electroencephalography and electrocardiography, along with signal detection theory analyses, we identify two distinct heartbeat-related influences on conscious perception differentially related to early vs. late somatosensory processing. First, an effect on early sensory processing was found for the heartbeat-evoked potential (HEP), a marker of cardiac interoception. The amplitude of the prestimulus HEP negatively correlated with localization and detection of somatosensory stimuli, reflecting a more conservative detection bias (criterion). Importantly, higher HEP amplitudes were followed by decreases in early (P50) as well as late (N140, P300) somatosensory-evoked potential (SEP) amplitudes. Second, stimulus timing along the cardiac cycle also affected perception. During systole, stimuli were detected and correctly localized less frequently, relating to a shift in perceptual sensitivity. This perceptual attenuation was accompanied by the suppression of only late SEP components (P300) and was stronger for individuals with a more stable heart rate. Both heart-related effects were independent of alpha oscillations' influence on somatosensory processing. We explain cardiac cycle timing effects in a predictive coding account and suggest that HEP-related effects might reflect spontaneous shifts between interoception and exteroception or modulations of general attentional resources. Thus, our results provide a general conceptual framework to explain how internal signals can be integrated into our conscious perception of the world.


Assuntos
Frequência Cardíaca/fisiologia , Interocepção/fisiologia , Percepção/fisiologia , Adulto , Atenção/fisiologia , Conscientização/fisiologia , Encéfalo/fisiologia , Mapeamento Encefálico/métodos , Estado de Consciência/fisiologia , Eletrocardiografia/métodos , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Potenciais Somatossensoriais Evocados/fisiologia , Feminino , Coração/fisiologia , Humanos , Masculino , Córtex Somatossensorial/fisiologia
13.
Neurobiol Aging ; 91: 125-135, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32241582

RESUMO

Contingency awareness is thought to rely on an intact medial temporal lobe and also appears to be a function of age, as older subjects tend to be less aware. The current investigation used functional magnetic resonance imaging, transcranial direct current stimulation, and eyeblink classical conditioning to study brain processes related to contingency awareness as a function of age. Older adults were significantly less aware of the relationship between the tone-airpuff pairings than younger adults. Greater right parietal functional magnetic resonance imaging activation was associated with higher levels of contingency awareness for younger and older subjects. Cathodal transcranial direct current stimulation over the right parietal lobe led to lower levels of awareness in younger subjects without disrupting conditioned responses. Older adults exhibited hyperactivations in the parietal and medial temporal lobes, despite showing no conditioning deficits. These findings strongly support the idea that the parietal cortex serves as a substrate for contingency awareness and that age-related disruption of this region is sufficient to impair awareness, which may be a manifestation of some form of naturally occurring age-related neglect.


Assuntos
Envelhecimento/psicologia , Conscientização/fisiologia , Lobo Parietal/fisiologia , Adulto , Idoso , Piscadela , Condicionamento Clássico , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Lobo Parietal/diagnóstico por imagem , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Adulto Jovem
14.
J Sports Sci Med ; 19(1): 112-120, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32132834

RESUMO

Recent research has shown multiple motives for high-risk sport participation derived from research on adult participants. The aim of this study was to provide insights into motives and risk-related aspects in adolescent high-risk sport participants and to compare those findings with adults performing the same activity. Semi-structured interviews were conducted with 24 adolescent (14-20 years) freeriders (skiers/snowboarders who ski outside the protected areas of a ski resort) and 24 adult freeriders (26-41 years). A content analyses was done using MAXQDA software. Both cohorts reported the motives Challenge (adolescents: 92%, adults: 88%), Freedom/Pleasure (adolescents: 88%, adults: 75%), Friends (adolescents: 88%, adults: 79%) and Balance (adolescents: 63%, adults: 63%). However, the description of friends differed between adults and adolescents. Whereas adolescents mostly referred to a community and shared interests, adults described the importance of trust and the development of deep friendships through the activity more often. Nature was a major motive in adults (83%) but not in adolescents (29%). Most of the adults have already experienced a major accident or close call (n = 19; 79%), contrary to adolescents (n = 7; 29%). Adolescents learned about the risks in freeriding primarily through their families (n = 10) and the ski club (n = 9). Some adults reported to have realized the risks involved in freeriding after starting with the activity due to experienced negative outcomes. Both cohorts were largely motivated by the same motives. As the new generation of freeriders seems to receive more instructions about risk reduction, it might be interesting to see if this educational approach results into less accidents or close calls in this group.


Assuntos
Motivação/fisiologia , Assunção de Riscos , Esqui/psicologia , Adolescente , Adulto , Fatores Etários , Conscientização/fisiologia , Feminino , Amigos/psicologia , Humanos , Entrevistas como Assunto , Masculino , Prazer/fisiologia , Pesquisa Qualitativa , Comportamento de Redução do Risco , Esqui/lesões , Adulto Jovem
15.
J Neurosci ; 40(14): 2906-2913, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32122954

RESUMO

To date it is poorly understood how and when deviance processing interacts with awareness and task relevance. Furthermore, an important issue in the study of consciousness is the prevalent confound of conscious perception with the requirement of reporting it. This study addresses these topics using a no-report inattentional blindness paradigm with a visual oddball sequence of geometrical shapes presented to male and female human participants. Electrophysiological responses were obtained in three physically identical Phases A-C that differed only with respect to the instructions: (A) participants were uninformed about the shapes and attended an unrelated foreground task (inattentional blind), (B) were informed about the shapes but still attended the foreground task, and (C) attended the shapes. Conscious processing of shapes was indexed by the visual awareness negativity but not a P3. Deviance processing was associated with the visual mismatch negativity independently of consciousness and task relevance. The oddball P3, however, only emerged when the stimuli were task relevant, and was absent for consciously perceived but task irrelevant stimuli. The P3 thus does not represent a reliable marker of stimulus awareness. This result pattern supports the view of hierarchical predictive processing, where lower levels display automatic deviance processing, whereas higher levels require attention and task relevance.SIGNIFICANCE STATEMENT To react to potentially important changes in our environment it is fundamental to detect deviations from regularities of sensory input. It has yet to be understood how awareness and task relevance of this input interact with deviance processing. We investigated the role of awareness in deviance detection while at the same time circumventing the confound of awareness and report by means of a no-report paradigm. Our results suggest that early processes are elicited automatically, whereas, contrary to prominent theories, late processes do not depend on awareness but on task-based attention.


Assuntos
Atenção/fisiologia , Conscientização/fisiologia , Encéfalo/fisiologia , Potenciais Evocados/fisiologia , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Percepção Visual/fisiologia , Adulto Jovem
16.
Sci Rep ; 10(1): 5419, 2020 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-32214173

RESUMO

Neural activity is known to oscillate within discrete frequency bands and the synchronization between these rhythms is hypothesized to underlie information integration in the brain. Since strict synchronization is only possible for harmonic frequencies, a recent theory proposes that the interaction between different brain rhythms is facilitated by transient harmonic frequency arrangements. In this line, it has been recently shown that the transient occurrence of 2:1 harmonic cross-frequency relationships between alpha and theta rhythms (i.e. falpha ≈ 12 Hz; ftheta ≈ 6 Hz) is enhanced during effortful cognition. In this study, we tested whether achieving a state of 'mental emptiness' during meditation is accompanied by a relative decrease in the occurrence of 2:1 harmonic cross-frequency relationships between alpha and theta rhythms. Continuous EEG recordings (19 electrodes) were obtained from 43 highly experienced meditators during meditation practice, rest and an arithmetic task. We show that the occurrence of transient alpha:theta 2:1 harmonic relationships increased linearly from a meditative to an active cognitive processing state (i.e. meditation < rest < arithmetic task). It is argued that transient EEG cross-frequency arrangements that prevent alpha:theta cross-frequency coupling could facilitate the experience of 'mental emptiness' by avoiding the interaction between the memory and executive components of cognition.


Assuntos
Ritmo alfa/fisiologia , Conscientização/fisiologia , Cognição/fisiologia , Meditação/psicologia , Descanso/fisiologia , Ritmo Teta/fisiologia , Adulto , Encéfalo , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Matemática/métodos , Pessoa de Meia-Idade
17.
J Abnorm Psychol ; 129(5): 445-456, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32202809

RESUMO

Interoceptive awareness (IA), or the awareness of internal body states, is known to be impaired in individuals with eating disorders (EDs); however, little is understood about how IA and ED symptoms are connected. Network analysis is a statistical approach useful for examining how symptoms interrelate and how comorbidities may be maintained. The present study used network analysis to (1) test central symptoms within an IA-ED network, (2) identify symptoms that may bridge the association between IA and ED symptoms, and (3) explore whether central and bridge symptoms predict ED remission at discharge from intensive treatment. A regularized partial correlation network was estimated in a sample of 428 adolescent (n = 187) and adult (n = 241) ED patients in a partial hospital program. IA was assessed using items from the Multidimensional Assessment of Interoceptive Awareness, and ED symptoms were assessed using items from the Eating Disorder Examination-Questionnaire. Central symptoms within the network were strong desire to lose weight, feeling guilty, and listening for information from the body about emotional state. The most central symptom bridging IA and ED symptoms was (not) feeling safe in one's body. Of the central symptoms, greater desire to lose weight predicted lower likelihood of remission at treatment discharge. Bridge symptoms did not significantly predict remission. Body mistrust may be a mechanism by which associations between IA and EDs are maintained. Findings suggest targeting central and bridge symptoms may be helpful to improve IA and ED symptoms. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Emoções/fisiologia , Transtornos da Alimentação e da Ingestão de Alimentos/fisiopatologia , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Interocepção/fisiologia , Adolescente , Adulto , Fatores Etários , Conscientização/fisiologia , Feminino , Humanos , Masculino , Adulto Jovem
18.
Sci Rep ; 10(1): 2038, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-32029854

RESUMO

The self is built as an entity independent from the external world using the human ability to experience the senses of agency and ownership. Humans usually experience these senses during movement. Nevertheless, researchers recently reported that another person's synchronous mirror-symmetrical movements elicited both agency and ownership in research participants. However, it is unclear whether this elicitation was caused by the synchronicity or the mirror symmetry of the movements. To address this question, we investigated the effect of interpersonal synchronization on the self-reported sense of agency and ownership in two conditions, using movements with and without mirror symmetry. Participants performed rhythmic hand movements while viewing the experimenter's synchronous or random hand movements, and then reported their perceptions of agency and ownership in a questionnaire. We observed that agency and ownership were significantly elicited by the experimenter's synchronous hand movements in both conditions. The results suggested that the synchronous movements of another person-rather than mirror- or non-mirror-symmetrical movements-appear to elicit the experience of a sense of agency and ownership. The results also suggested that people could experience these senses not only from their own movements but also from another person's synchronous movements.


Assuntos
Conscientização/fisiologia , Mãos/fisiologia , Percepção de Movimento/fisiologia , Movimento/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
19.
Atten Percept Psychophys ; 82(4): 1586-1598, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31970711

RESUMO

Visual attention can sometimes be involuntarily captured by salient stimuli, and this may lead to impaired performance in a variety of real-world tasks. If observers were aware that their attention was being captured, they might be able to exert control and avoid subsequent distraction. However, it is unknown whether observers can detect attention capture when it occurs. In the current study, participants searched for a target shape and attempted to ignore a salient color distractor. On a subset of trials, participants then immediately classified whether the salient distractor captured their attention ("capture" vs. "no capture"). Participants were slower and less accurate at detecting the target on trials on which they reported "capture" than "no capture." Follow-up experiments revealed that participants specifically detected covert shifts of attention to the salient item. Altogether, these results indicate that observers can have immediate awareness of visual distraction, at least under certain circumstances.


Assuntos
Atenção/fisiologia , Conscientização/fisiologia , Percepção de Cores/fisiologia , Estimulação Luminosa/métodos , Pensamento/fisiologia , Adolescente , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia , Adulto Jovem
20.
Am J Clin Hypn ; 62(3): 198-230, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31928516

RESUMO

The Thought Impact Scale (TIS) is a new questionnaire designed to measure the theorized psychological characteristic of subconscious connectedness, defined as the degree to which nonconscious mental functions spontaneously interact with, and are accessible to, conscious awareness in everyday life. A principal reason for developing the TIS was the expectation that subconscious connectedness influences hypnosis treatment responses and seeking of hypnosis treatment. Two studies involving 1,216 subjects were carried out to validate the questionnaire. The TIS exhibited high internal consistency (Cronbach's alpha of 0.93 and 0.95), good one-month test-retest reliability (r = 0.89), and convergent validity evidenced by substantial correlations with other measures hypothesized to partly assess the same construct: Absorption (r = 0.70), fantasy proneness (r = 0.54), dissociation (r = 0.50), and emotional empathy (r = 0.39). TIS scores were approximately normally distributed, higher in females than males, and declining with age. Exploratory factor analysis showed the TIS to be composed of a single dominant factor. High TIS scorers were 2.5 times as likely as low scorers to have undergone hypnosis treatment, 2.6 times as likely to report at least moderate benefit after hypnosis treatment, and 3.8 times as likely to consider themselves highly hypnotizable. High TIS scorers also more frequently reported being highly creative, art lovers, intuition-reliant, absentminded, spontaneous, novelty-seeking, and prone to form intense relationships. The TIS is a reliable and valid measure that is likely to be useful in clinical hypnosis practice and hypnosis research and for quantifying communication between conscious and nonconscious mental functions.


Assuntos
Conscientização/fisiologia , Hipnose , Psicometria/normas , Pensamento/fisiologia , Inconsciente Psicológico , Adulto , Feminino , Humanos , Masculino , Psicometria/instrumentação , Reprodutibilidade dos Testes
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