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1.
Psychophysiology ; 61(11): e14656, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39095947

RESUMO

The neurological basis for perceptual awareness remains unclear, and theories disagree as to whether sensory cortices per se generate awareness. Critically, neural activity in the sensory cortices is only a neural correlate of consciousness (NCC) if it closely matches the contents of perceptual awareness. Research in vision and touch suggest that contralateral activity in sensory cortices is an NCC. Similarly, research in hearing with two sound sources (left and right) presented over headphones also suggests that a candidate NCC called the auditory awareness negativity (AAN) matches perceived location of sound. The current study used 13 different sound sources presented over loudspeakers for natural localization cues and measured event-related potentials to a threshold stimulus in a sound localization task. Preregistered Bayesian mixed models provided moderate evidence against an overall AAN and very strong evidence against its lateralization. Because of issues regarding data quantity and quality, exploratory analyses with aggregated data from multiple loudspeakers were conducted. Results provided moderate evidence for an overall AAN and strong evidence against its lateralization. Nonetheless, the interpretations of these results remain inconclusive. Therefore, future research should reduce the number of conditions and/or test over several sessions to procure a sufficient amount of data. Taken at face value, the results may suggest issues with AAN as an NCC of auditory awareness, as it does not laterally map onto experiences in a free-field auditory environment, in contrast to the NCCs of vision and touch.


Assuntos
Percepção Auditiva , Conscientização , Eletroencefalografia , Lateralidade Funcional , Localização de Som , Humanos , Conscientização/fisiologia , Feminino , Masculino , Adulto Jovem , Adulto , Lateralidade Funcional/fisiologia , Localização de Som/fisiologia , Percepção Auditiva/fisiologia , Potenciais Evocados Auditivos/fisiologia , Estimulação Acústica , Potenciais Evocados/fisiologia , Adolescente
2.
Cogn Affect Behav Neurosci ; 23(5): 1303-1321, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37656374

RESUMO

Humans have conscious experiences of the events in their environment. Previous research from electroencephalography (EEG) has shown visual awareness negativity (VAN) at about 200 ms to be a neural correlate of consciousness (NCC). However, when considering VAN as an NCC, it is important to explore which particular experiences are associated with VAN. Recent research proposes that VAN is an NCC of lower-level experiences (detection) rather than higher-level experiences (identification). However, previous results are mixed and have several limitations. In the present study, the stimulus was a ring with a Gabor patch tilting either left or right. On each trial, subjects rated their awareness on a three-level perceptual awareness scale that captured both detection (something vs. nothing) and identification (identification vs. something). Separate staircases were used to adjust stimulus opacity to the detection threshold and the identification threshold. Bayesian linear mixed models provided extreme evidence (BF10 = 131) that VAN was stronger at the detection threshold than at the identification threshold. Mean VAN decreased from [Formula: see text]2.12 microV [[Formula: see text]2.86, [Formula: see text]1.42] at detection to [Formula: see text]0.46 microV [[Formula: see text]0.79, [Formula: see text]0.11] at identification. These results strongly support the claim that VAN is an NCC of lower-level experiences of seeing something rather than of higher-level experiences of specific properties of the stimuli. Thus, results are consistent with recurrent processing theory in that phenomenal visual consciousness is reflected by VAN. Further, results emphasize that it is important to consider the level of experience when searching for NCC.


Assuntos
Potenciais Evocados , Percepção Visual , Humanos , Potenciais Evocados/fisiologia , Percepção Visual/fisiologia , Conscientização/fisiologia , Teorema de Bayes , Eletroencefalografia , Estado de Consciência/fisiologia
3.
Conscious Cogn ; 83: 102954, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32485343

RESUMO

Research suggests that the electrophysiological correlates of consciousness are similar in hearing as in vision: the auditory awareness negativity (AAN) and the late positivity (LP). However, from a recently proposed signal-detection perspective, these correlates may be confounded by performance, as the strength of the internal responses differs between aware and unaware trials. Here, we tried to apply this signal-detection approach to correct for performance in an auditory discrimination and detection task (N = 28). A large proportion of subjects had to be excluded because even a small response bias distorted the correction. For the remaining subjects, the correction mainly increased noise in the measurement. Furthermore, the signal-detection approach is theoretically problematic because it may isolate post-perceptual processes and eliminate awareness-related activity. Therefore, we conclude that AAN and LP are not confounded by performance and that the contrastive analysis identifies both as correlates of awareness.


Assuntos
Conscientização/fisiologia , Estado de Consciência/fisiologia , Potenciais Evocados/fisiologia , Discriminação da Altura Tonal/fisiologia , Detecção de Sinal Psicológico/fisiologia , Adolescente , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Adulto Jovem
4.
Conscious Cogn ; 71: 70-78, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30928900

RESUMO

One theory of visual awareness proposes that electrophysiological activity related to awareness occurs in primary visual areas approximately 200 ms after stimulus onset (visual awareness negativity: VAN) and in fronto-parietal areas about 300 ms after stimulus onset (late positivity: LP). Although similar processes might be involved in auditory awareness, only sparse evidence exists for this idea. In the present study, we recorded electrophysiological activity while subjects listened to tones that were presented at their own awareness threshold. The difference in electrophysiological activity elicited by tones that subjects reported being aware of versus unaware of showed an early negativity about 200 ms and a late positivity about 300 ms after stimulus onset. These results closely match those found in vision and provide convincing evidence for an early negativity (auditory awareness negativity: AAN), as well as an LP. These findings suggest that theories of visual awareness are also applicable to auditory awareness.


Assuntos
Limiar Auditivo/fisiologia , Conscientização/fisiologia , Córtex Cerebral/fisiologia , Potenciais Evocados/fisiologia , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Adulto Jovem
5.
Cogn Affect Behav Neurosci ; 18(1): 176-188, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29344763

RESUMO

Electrophysiological recordings are commonly used to study the neural correlates of consciousness in humans. Previous research is inconsistent as to whether awareness can be indexed with visual awareness negativity (VAN) at about 200 ms or if it occurs later. The present study was preregistered with two main aims: First, to provide independent evidence for or against the presence of VAN, and second, to study whether stimulus size may account for the inconsistent findings. Subjects were shown low-contrast Gaussian filtered gratings (Gabor patches) in the four visual quadrants. Gabor size (large and small) was varied in different sessions and calibrated to each subject's threshold of visual awareness. Event-related potentials were derived from trials in which subjects localized the Gabors correctly to capture the difference between trials in which they reported awareness versus no awareness. Bayesian analyses revealed very strong evidence for the presence of VAN for both Gabor sizes. However, there was no evidence for or against an effect of stimulus size. The present findings provide evidence for VAN as an early neural correlate of awareness.


Assuntos
Conscientização/fisiologia , Estado de Consciência/fisiologia , Potenciais Evocados Visuais/fisiologia , Potenciais Evocados/fisiologia , Percepção Visual/fisiologia , Adulto , Encéfalo/fisiologia , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Adulto Jovem
6.
Perception ; 46(3-4): 530-537, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28056659

RESUMO

Autism spectrum disorders (ASD) are often characterized by atypical sensory behavior (hyper- or hyporeactivity) although evidence is scarce regarding olfactory abilities in ASD; 16 adults with high-functioning ASD (mean age: 38.2, SD: 9.7) and 14 healthy control subjects (mean age: 42.0 years, SD: 12.5) were assessed in odor threshold, free and cued odor identification, and perceived pleasantness, intensity, and edibility of everyday odors. Although results showed no differences between groups, the Bayes Factors (close to 1) suggested that the evidence for no group differences on the threshold and identification tests was inconclusive. In contrast, there was some evidence for no group differences on perceived edibility (BF01 = 2.69) and perceived intensity (BF01 = 2.80). These results do not provide conclusive evidence for or against differences between ASD and healthy controls on olfactory abilities. However, they suggest that there are no apparent group differences in subjective ratings of odors.


Assuntos
Transtorno do Espectro Autista/psicologia , Percepção Olfatória , Limiar Sensorial , Adulto , Teorema de Bayes , Estudos de Casos e Controles , Emoções , Feminino , Preferências Alimentares/psicologia , Humanos , Masculino , Reconhecimento Psicológico , Adulto Jovem
7.
Neuroimage ; 77: 254-61, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23298751

RESUMO

The present study compared the temporal and spatial aspects of human olfactory and trigeminal processing. A relatively selective trigeminal stimulus, CO2, and a relatively selective olfactory stimulus, H2S, were delivered with an olfactometer to young, healthy volunteers. The analysis was performed in a classical (5-electrode, main ERPs peaks) and modern approach (high topographical resolution, inverse solution, source localization). Results of microstate segmentation highlighted 5 maps that generally described the two processes at cerebral level. The trigeminal response differed from the olfactory response up to 300ms after stimulus onset. In this time range, source analysis pointed out that the olfactory stimulation involved olfactory related areas, while trigeminal stimulation involved noxious/somatosensory specific brain areas. Moreover, from 300ms on our data showed a similarity between the two processes. Statistical parametrical mapping of the differences between conditions suggested greater activation in a specific motor/sniffing network for the CO2 stimulation (probably related to a regulation of the potential noxious stimulus) and a greater activation of the ipsilateral primary olfactory cortex for H2S.


Assuntos
Mapeamento Encefálico/métodos , Potenciais Evocados/fisiologia , Percepção Olfatória/fisiologia , Adulto , Dióxido de Carbono/toxicidade , Eletroencefalografia , Potenciais Evocados/efeitos dos fármacos , Feminino , Humanos , Sulfeto de Hidrogênio/toxicidade , Nervo Olfatório/fisiologia , Processamento de Sinais Assistido por Computador , Estimulação Química , Nervo Trigêmeo/fisiologia , Adulto Jovem
8.
BMC Neurosci ; 14: 139, 2013 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-24207058

RESUMO

BACKGROUND: When people view emotional and neutral pictures, the emotional pictures capture more attention than do neutral pictures. In support, studies with event-related potentials have shown that the early posterior negativity (EPN) and the late positive potential (LPP) to emotional versus neutral pictures are enhanced when pictures are attended. However, this motivated attention decreases when voluntary attention is directed away from the pictures. Most previous studies included only generally emotional pictures of either negative or positive valence. Because people with spider fear report intense fear of spiders, we examined whether directing attention away from emotional pictures at fixation decreases motivated attention less strongly for spiders than for generally negative distracters. RESULTS: We recorded event-related potentials from 128 channels to study whether manipulations of attention (i.e., spatial attention and perceptual load) decrease the EPN and the LPP to emotional distracters less strongly for spiders than for fear-irrelevant negative pictures in people with spider fear. Results confirmed that the EPN and the LPP to spiders (vs. neutral pictures) were particularly enhanced in participants with spider fear compared to participants without spider fear. When attention was directed away from the pictures, the EPN and the LPP to spiders (vs. neutral pictures) decreased similarly in fearful and nonfearful participants. Further, in fearful participants, the decrease in the EPN and the LPP was similar for spiders and for fear-irrelevant negative pictures. CONCLUSIONS: Our findings suggest that for people with spider fear, directing attention away from emotional pictures at fixation decreases motivated attention to these distracters similarly for spiders as for fear-irrelevant negative pictures. These findings imply that attention to spiders in spider fear does not exceed the level of attention expected from the spider pictures' high arousal and negative valence (i.e., their intrinsic motivated attention).


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Potenciais Evocados/fisiologia , Medo/fisiologia , Adulto , Animais , Eletroencefalografia , Feminino , Humanos , Masculino , Estimulação Luminosa , Aranhas , Adulto Jovem
9.
Cogn Affect Behav Neurosci ; 12(1): 151-60, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22095306

RESUMO

Previous research suggests that intense, emotional pictures at fixation elicit an early posterior negativity (EPN) and a late positive potential (LPP) despite manipulations of spatial inattention and perceptual load. However, if high emotional intensity protects against such manipulations, then these manipulations should reduce emotional effects on EPN and LPP more strongly for medium than for intense emotional pictures. To test this prediction, pictures that were high negative, medium negative, or neutral were shown at fixation, and a small letter string was superimposed on the picture center. When participants attended the pictures, there were clear emotional effects on EPN and LPP. When participants attended the letter string, the emotional effects on LPP decreased; this decrease was smaller for medium than for high negative pictures. Thus, opposite of predictions, spatial inattention reduced the emotional effects more strongly for high than for medium negative pictures. As a manipulation of perceptual load, participants performed the letter task with one, three, or six relevant letters. Irrespective of load, EPN and LPP were similar for high and medium negative pictures. Our findings suggest that high negative valence does not protect EPN and LPP more strongly from effects of spatial inattention and perceptual load than does medium negative valence.


Assuntos
Atenção/fisiologia , Variação Contingente Negativa/fisiologia , Emoções/fisiologia , Potenciais Evocados/fisiologia , Percepção Visual/fisiologia , Adulto , Análise de Variância , Mapeamento Encefálico , Eletroencefalografia , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Adulto Jovem
10.
BMC Neurosci ; 13: 49, 2012 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-22607397

RESUMO

BACKGROUND: In research on event-related potentials (ERP) to emotional pictures, greater attention to emotional than neutral stimuli (i.e., motivated attention) is commonly indexed by two difference waves between emotional and neutral stimuli: the early posterior negativity (EPN) and the late positive potential (LPP). Evidence suggests that if attention is directed away from the pictures, then the emotional effects on EPN and LPP are eliminated. However, a few studies have found residual, emotional effects on EPN and LPP. In these studies, pictures were shown at fixation, and picture composition was that of simple figures rather than that of complex scenes. Because figures elicit larger LPP than do scenes, figures might capture and hold attention more strongly than do scenes. Here, we showed negative and neutral pictures of figures and scenes and tested first, whether emotional effects are larger to figures than scenes for both EPN and LPP, and second, whether emotional effects on EPN and LPP are reduced less for unattended figures than scenes. RESULTS: Emotional effects on EPN and LPP were larger for figures than scenes. When pictures were unattended, emotional effects on EPN increased for scenes but tended to decrease for figures, whereas emotional effects on LPP decreased similarly for figures and scenes. CONCLUSIONS: Emotional effects on EPN and LPP were larger for figures than scenes, but these effects did not resist manipulations of attention more strongly for figures than scenes. These findings imply that the emotional content captures attention more strongly for figures than scenes, but that the emotional content does not hold attention more strongly for figures than scenes.


Assuntos
Atenção/fisiologia , Mapeamento Encefálico , Emoções , Potenciais Evocados Visuais/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Análise de Variância , Eletroencefalografia , Feminino , Lateralidade Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Fatores de Tempo , Adulto Jovem
11.
Memory ; 20(4): 321-31, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22364145

RESUMO

Previous research suggests that the own-race bias (ORB) in memory for faces is a result of other-race faces receiving less visual attention at encoding. As women typically display an own-gender bias in memory for faces and men do not, we investigated whether face gender and sex of viewer influenced visual attention and memory for own- and other-race faces, and if preferential viewing of own-race faces contributed to the ORB in memory. Participants viewed pairs of female or male own- and other-race faces while their viewing time was recorded. Afterwards, they completed a surprise memory test. We found that (1) other-race males received the initial focus of attention, (2) own-race faces were viewed longer than other-race faces over time, although the difference was larger for female faces, and (3) even though longer viewing time increased the probability of remembering a face, it did not explain the magnified ORB in memory for female faces. Importantly, these findings highlight that face gender moderates attentional responses to and memory for own- and other-race faces.


Assuntos
Atenção , Face , Memória , Reconhecimento Visual de Modelos , Grupos Raciais/psicologia , Reconhecimento Psicológico , Adulto , Feminino , Humanos , Modelos Logísticos , Masculino , Estimulação Luminosa/métodos , Caracteres Sexuais , Adulto Jovem
12.
Cogn Emot ; 26(2): 252-60, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21973031

RESUMO

Theories of emotion propose that responses to emotional pictures can occur independently of whether or not people are aware of the picture content. Because evidence from dissociation paradigms is inconclusive, we manipulated picture awareness gradually and studied whether emotional responses varied with degree of awareness. Spider fearful and non-fearful participants viewed pictures of spiders and flowers at four levels of backward masking while electrodermal activity and heart rate were measured continuously. Recognition ratings confirmed that participants' picture awareness decreased with masking. Critically, effects of spider fear on emotion ratings and heart rate also decreased with masking. These findings suggest that effects of spider fear on emotion ratings and heart rate are closely related to picture awareness.


Assuntos
Conscientização/fisiologia , Emoções/fisiologia , Mascaramento Perceptivo/fisiologia , Transtornos Fóbicos/fisiopatologia , Transtornos Fóbicos/psicologia , Reconhecimento Psicológico/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Resposta Galvânica da Pele/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Estimulação Luminosa/métodos , Desempenho Psicomotor/fisiologia
13.
Psychophysiology ; 59(12): e14123, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35751845

RESUMO

The C1 event-related potential (ERP) captures the earliest stage of feedforward processing in the primary visual cortex (V1). An ongoing debate is whether top-down selective attention can modulate the C1. One side of the debate pointed out that null findings appear to outnumber positive findings; thus, selective attention does not seem to influence the C1. However, this suggestion is not based on a valid approach to summarizing evidence across studies. Therefore, we conducted a systematic review and meta-analysis investigating the effects of selective attention on the C1, involving 47 experiments and 794 subjects in total. Despite heterogeneity across studies, results suggested that attention has a moderate effect on the C1 (Cohen's d z  = 0.33, p < .0001); that is, C1 amplitude is larger for visual stimuli that are attended than unattended. These results suggest that C1 is affected by top-down selective attention.


Assuntos
Potenciais Evocados Visuais , Córtex Visual , Humanos , Percepção Visual , Estimulação Luminosa , Eletroencefalografia , Mapeamento Encefálico/métodos , Atenção , Potenciais Evocados
14.
Psychophysiology ; 59(12): e14117, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35687668

RESUMO

Specific phobia can be treated successfully with exposure therapy. Although exposure therapy has strong effects on self-reported ratings and behavioral avoidance, effects on measures derived from electroencephalography (EEG) are scant and unclear. To fill this gap, spider-phobic individuals received either in-vivo or virtual reality exposure treatment. Patients were tested twice (one week before and after treatment), and control subjects once. In each session, EEG was recorded to spider pictures as well as other positive, negative, and neutral pictures. During EEG recording, participants performed a simple detection task while task-irrelevant pictures were shown in the background. The task was used to reduce potential confounding effects from shifts of attention. After the task, subjects were shown the pictures again and rated each in terms of their emotional reaction (arousal and pleasantness). The results showed that before treatment, patients rated spiders as more negative than did control subjects. Patients also showed elevated early posterior negativity (EPN) and late positive potential (LPP) to spiders. After treatment, the negative emotional ratings of spiders were substantially reduced. Critically, Bayesian analyses suggested that EPN and LPP were unaffected by treatment and that the treatment groups did not differ in their responses (EPN, LPP, and ratings). These findings suggest that the effects of in vivo and virtual reality exposure therapy are similar and that the initial stages of motivated attention (EPN and LPP) are unaffected by treatment.


Assuntos
Transtornos Fóbicos , Aranhas , Terapia de Exposição à Realidade Virtual , Animais , Terapia de Exposição à Realidade Virtual/métodos , Estimulação Luminosa , Teorema de Bayes , Transtornos Fóbicos/terapia , Transtornos Fóbicos/psicologia , Eletroencefalografia
15.
Physiol Behav ; 228: 113240, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33188789

RESUMO

Ignoring background sounds while focusing on a visual task is a necessary ability in everyday life. If attentional resources are shared between modalities, processing of task-irrelevant auditory information should become attenuated when attentional capacity is expended by visual demands. According to the early-filter model, top-down attenuation of auditory responses is possible at various stages of the auditory pathway through multiple recurrent loops. Furthermore, the adaptive filtering model of selective attention suggests that filtering occurs early when concurrent visual tasks are demanding (e.g., high load) and late when tasks are easy (e.g., low load). To test these models, this study examined the effects of three levels of visual load on auditory steady-state responses (ASSRs) at three modulation frequencies. Subjects performed a visual task with no, low, and high visual load while ignoring task-irrelevant sounds. The auditory stimuli were 500-Hz tones amplitude-modulated at 20, 40, or 80 Hz to target different processing stages of the auditory pathway. Results from bayesian analyses suggest that ASSRs are unaffected by visual load. These findings imply that attentional resources are modality specific and that the attentional filter of auditory processing does not vary with visual task demands.


Assuntos
Percepção Auditiva , Potenciais Evocados Auditivos , Estimulação Acústica , Atenção , Teorema de Bayes , Eletroencefalografia
16.
Neuropsychologia ; 158: 107910, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34090867

RESUMO

Theories disagree as to whether it is the early or the late neural correlate of awareness that plays a critical role in phenomenal awareness. According to recurrent processing theory, early activity in primary sensory areas corresponds closely to phenomenal awareness. In support, research with electroencephalography found that in the visual and somatosensory modality, an early neural correlate of awareness is contralateral to the perceived side of stimulation. Thus, early activity is sensitive to the perceived side of visual and somatosensory stimulation. Critically, it is unresolved whether this is true also for hearing. In the present study (N = 26 students), Bayesian analyses showed that the early neural correlate of awareness (auditory awareness negativity, AAN) was stronger for contralateral than ipsilateral electrodes whereas the late correlate of auditory awareness (late positivity, LP) was not lateralized. These findings demonstrate that the early but not the late neural correlate of auditory awareness reflects lateralized experiences. Thus, these findings imply that AAN is a more suitable NCC than LP because it correlates more closely with lateralized experiences.


Assuntos
Conscientização , Potenciais Evocados , Teorema de Bayes , Eletroencefalografia , Humanos , Percepção Visual
17.
Brain ; 132(Pt 11): 3021-31, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19767414

RESUMO

Affective neuroscience has been strongly influenced by the view that a 'feeling' is the perception of somatic changes and has consequently often neglected the neural mechanisms that underlie the integration of somatic and other information in affective experience. Here, we investigate affective processing by means of functional magnetic resonance imaging in nine cortically blind patients. In these patients, unilateral postgeniculate lesions prevent primary cortical visual processing in part of the visual field which, as a result, becomes subjectively blind. Residual subcortical processing of visual information, however, is assumed to occur in the entire visual field. As we have reported earlier, these patients show significant startle reflex potentiation when a threat-related visual stimulus is shown in their blind visual field. Critically, this was associated with an increase of brain activity in somatosensory-related areas, and an increase in experienced negative affect. Here, we investigated the patients' response when the visual stimulus was shown in the sighted visual field, that is, when it was visible and cortically processed. Despite the fact that startle reflex potentiation was similar in the blind and sighted visual field, patients reported significantly less negative affect during stimulation of the sighted visual field. In other words, when the visual stimulus was visible and received full cortical processing, the patients' phenomenal experience of affect did not closely reflect somatic changes. This decoupling of phenomenal affective experience and somatic changes was associated with an increase of activity in the left ventrolateral prefrontal cortex and a decrease of affect-related somatosensory activity. Moreover, patients who showed stronger left ventrolateral prefrontal cortex activity tended to show a stronger decrease of affect-related somatosensory activity. Our findings show that similar affective somatic changes can be associated with different phenomenal experiences of affect, depending on the depth of cortical processing. They are in line with a model in which the left ventrolateral prefrontal cortex is a relay station that integrates information about subcortically triggered somatic responses and information resulting from in-depth cortical stimulus processing. Tentatively, we suggest that the observed decoupling of somatic responses and experienced affect, and the reduction of negative phenomenal experience, can be explained by a left ventrolateral prefrontal cortex-mediated inhibition of affect-related somatosensory activity.


Assuntos
Afeto/fisiologia , Cegueira Cortical/fisiopatologia , Córtex Pré-Frontal , Vias Visuais/patologia , Vias Visuais/fisiologia , Percepção Visual/fisiologia , Estimulação Acústica , Adulto , Cegueira Cortical/patologia , Expressão Facial , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Reconhecimento Visual de Modelos/fisiologia , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/fisiopatologia , Desempenho Psicomotor/fisiologia , Reflexo , Visão Ocular/fisiologia , Córtex Visual/fisiologia , Vias Visuais/fisiopatologia
18.
Psychophysiology ; 57(12): e13689, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32944959

RESUMO

The auditory pathway consists of multiple recurrent loops of afferent and efferent connections that extend from the cochlea up to the prefrontal cortex. The early-filter theory proposes that these loops allow top-down filtering of early and middle latency auditory responses. Furthermore, the adaptive filtering model suggests that the filtering of irrelevant auditory stimuli should start lower in the pathway during more demanding tasks. If so, the 40-Hz auditory steady-state responses (ASSRs) to irrelevant sounds should be affected by top-down crossmodal attention to a visual task, and effects should vary with the load of the visual task. Because few studies have examined this possibility, we conducted two preregistered studies that manipulated visual load (Study 1: N = 43, Study 2: N = 45). Study 1 used two levels (low and high), and Study 2 used four levels (no, low, high, and very high). Subjects were asked to ignore a 500-Hz task-irrelevant tone that was amplitude-modulated to evoke 40-Hz ASSRs. Results from Bayesian analyses provided moderate to extreme support for no effect of load (or of a task) on ASSRs. Results also supported no interaction with time (i.e., over blocks, over minutes, or with changes in ASSRs that were synchronized with the onset of the visual stimuli). Further, results provided moderate support for no correlation between the effects of load and working memory capacity. Because the present findings support the robustness of ASSRs against manipulations of crossmodal attention, they are not consistent with the adaptive filtering model.


Assuntos
Percepção Auditiva/fisiologia , Potenciais Evocados P300/fisiologia , Potenciais Evocados Auditivos/fisiologia , Potenciais Evocados Visuais/fisiologia , Memória de Curto Prazo/fisiologia , Desempenho Psicomotor/fisiologia , Percepção Visual/fisiologia , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Adulto Jovem
19.
Front Psychol ; 10: 2083, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31551899

RESUMO

In hearing, two neural correlates of awareness are the auditory awareness negativity (AAN) and the late positivity (LP). These correlates of auditory awareness are typically observed with tasks in which subjects are required to report their awareness with manual responses. Thus, the correlates may be confounded by this manual response requirement. We manipulated the response requirement in a tone detection task (N = 52). Tones were presented at each subject's individual awareness threshold while high-density electroencephalography (EEG) activity was recorded. In one response condition, subjects pushed a button if they were aware of the tone and withheld responding if they were unaware of the tone. In the other condition, subjects pushed a button if they were unaware of the tone and withheld responding if they were aware of the tone. To capture AAN and LP, difference waves were computed between aware and unaware trials, separately for trials in which responses were required and trials in which responses were not required. Results suggest that AAN and LP are unaffected by the response requirement. These findings imply that in hearing, early and late correlates of awareness are not confounded by a manual response requirement. Furthermore, the results suggest that AAN originates from bilateral auditory cortices, supporting the view that AAN is a neural correlate of localized recurrent processing in early sensory areas.

20.
Psychophysiology ; 56(1): e13280, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30246255

RESUMO

The mismatch negativity (MMN) has been widely studied with oddball tasks to index processing of unexpected auditory change. The MMN is computed as the difference of deviant minus standard and is used to capture the pattern violation by the deviant. However, this oddball MMN is confounded because the deviant differs physically from the standard and is presented less often. To improve measurement, the same tone as the deviant is presented in a separate condition. This control tone is equiprobable with other tones and is used to compute a corrected MMN (deviant minus control). Typically, the tones are in random order except that consecutive tones are not identical (no-repetition rule). In contrast, a recent study on frequency MMN presented tones in a regular up-and-down sequence (cascade rule). If the cascade rule is detected more easily than the no-repetition rule, there should be a lower risk of a confounding MMN within the cascade condition. However, in previous research, the cascade and no-repetition conditions differed not only in the regularity of the tone sequence but also in number of tones, frequency range, and proportion of tones. We controlled for these differences to isolate effects of regularity in the tone sequence. Results of our preregistered analyses provided moderate evidence (BF01 >6) that the corrected MMN did not differ between cascade and no-repetition conditions. These findings imply that no-repetition and cascade rules are processed similarly and that the no-repetition condition provides an adequate control in frequency MMN.


Assuntos
Córtex Auditivo/fisiologia , Percepção Auditiva/fisiologia , Potenciais Evocados Auditivos/fisiologia , Estimulação Acústica , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia , Adulto Jovem
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