1
|
Ciupińska K, Orłowska W, Zębrowski A, Łępa L, Koculak M, Bola M, Wierzchoń M. The influence of spatial and temporal attention on visual awareness-a behavioral and ERP study. Cereb Cortex 2024; 34:bhae241. [PMID: 38850216 DOI: 10.1093/cercor/bhae241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 05/14/2024] [Accepted: 05/22/2024] [Indexed: 06/10/2024] Open
Abstract
Whether attention is a prerequisite of perceptual awareness or an independent and dissociable process remains a matter of debate. Importantly, understanding the relation between attention and awareness is probably not possible without taking into account the fact that both are heterogeneous and multifaceted mechanisms. Therefore, the present study tested the impact on visual awareness of two attentional mechanisms proposed by the Posner model: temporal alerting and spatio-temporal orienting. Specifically, we evaluated the effects of attention on the perceptual level, by measuring objective and subjective awareness of a threshold-level stimulus; and on the neural level, by investigating how attention affects two postulated event-related potential correlates of awareness. We found that alerting and orienting mechanisms additively facilitate perceptual consciousness, with activation of the latter resulting in the most vivid awareness. Furthermore, we found that late positivity is unlikely to constitute a neural correlate of consciousness as its amplitude was modulated by both attentional mechanisms, but early visual awareness negativity was independent of the alerting and orienting mechanisms. In conclusion, our study reveals a nuanced relationship between attention and awareness; moreover, by investigating the effect of the alerting mechanism, this study provides insights into the role of temporal attention in perceptual consciousness.
Collapse
Affiliation(s)
- Kinga Ciupińska
- Consciousness Lab, Institute of Psychology, Jagiellonian University, 6 Ingardena Street, 30-060 Krakow, Poland
- Social Cognition in Human-Robot Interaction (S4HRI), Italian Institute of Technology, via Enrico Melen 83, 16152 Genova, Italy
| | - Wiktoria Orłowska
- Consciousness Lab, Institute of Psychology, Jagiellonian University, 6 Ingardena Street, 30-060 Krakow, Poland
- Doctoral School in the Social Sciences, Jagiellonian University, 34 Rynek Główny, 31-010 Krakow, Poland
| | - Aleksander Zębrowski
- Doctoral School in the Social Sciences, Jagiellonian University, 34 Rynek Główny, 31-010 Krakow, Poland
- Centre for Brain Research, Jagiellonian University, 50 Kopernika Street, 31-501 Krakow, Poland
| | - Laura Łępa
- Consciousness Lab, Institute of Psychology, Jagiellonian University, 6 Ingardena Street, 30-060 Krakow, Poland
| | - Marcin Koculak
- Consciousness Lab, Institute of Psychology, Jagiellonian University, 6 Ingardena Street, 30-060 Krakow, Poland
| | - Michał Bola
- Centre for Brain Research, Jagiellonian University, 50 Kopernika Street, 31-501 Krakow, Poland
| | - Michał Wierzchoń
- Consciousness Lab, Institute of Psychology, Jagiellonian University, 6 Ingardena Street, 30-060 Krakow, Poland
- Centre for Brain Research, Jagiellonian University, 50 Kopernika Street, 31-501 Krakow, Poland
| |
Collapse
|
2
|
Doradzińska Ł, Bola M. Early Electrophysiological Correlates of Perceptual Consciousness Are Affected by Both Exogenous and Endogenous Attention. J Cogn Neurosci 2024; 36:1297-1324. [PMID: 38579265 DOI: 10.1162/jocn_a_02156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2024]
Abstract
It has been proposed that visual awareness negativity (VAN), which is an early ERP component, constitutes a neural correlate of visual consciousness that is independent of perceptual and cognitive mechanisms. In the present study, we investigated whether VAN is indeed a specific marker of phenomenal awareness or rather reflects the involvement of attention. To this end, we reanalyzed data collected in a previously published EEG experiment in which awareness of visual stimuli and two aspects that define attentional involvement, namely, the inherent saliency and task relevance of a stimulus, were manipulated orthogonally. During the experimental procedure, participants (n = 41) were presented with images of faces that were backward-masked or unmasked, fearful or neutral, and defined as task-relevant targets or task-irrelevant distractors. Single-trial ERP analysis revealed that VAN was highly dependent on attentional manipulations in the early time window (140-200 msec), up to the point that the effect of awareness was not observed for attentionally irrelevant stimuli (i.e., neutral faces presented as distractors). In the late time window (200-350 msec), VAN was present in all attentional conditions, but its amplitude was significantly higher in response to fearful faces and task-relevant face images than in response to neutral ones and task-irrelevant ones, respectively. In conclusion, we demonstrate that the amplitude of VAN is highly dependent on both exogenous (stimulus saliency) and endogenous attention (task requirements). Our results challenge the view that VAN constitutes an attention-independent correlate of phenomenal awareness.
Collapse
Affiliation(s)
- Łucja Doradzińska
- Nencki Institute of Experimental Biology of Polish Academy of Sciences, Warsaw, Poland
| | - Michał Bola
- Centre for Brain Research, Jagiellonian University, Krakow, Poland
| |
Collapse
|
3
|
Ye M, Wang A, Liang H, Liu X. Late Positivity Correlates with Subjective Reports: Evidence from the Low-frequency and High-frequency Reporting Tasks. Neuroscience 2024; 546:143-156. [PMID: 38574798 DOI: 10.1016/j.neuroscience.2024.03.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 03/18/2024] [Accepted: 03/29/2024] [Indexed: 04/06/2024]
Abstract
Identifying the neural correlates of consciousness (NCCs) is an important way to understand the fundamental nature of consciousness. By recording event-related potentials (ERPs) using EEG, researchers have found three potential electrophysiological NCCs: early positive correlate of consciousness (enhanced P1), visual awareness negativity (VAN), and late positivity (LP). However, LP may reflect post-perceptual processing associated with subjective reports rather than consciousness per se. The present experiment investigated the relationship between LP and subjective reports. We adopted two subjective reporting tasks that differed in the requirement for subjective reports. In the low-frequency reporting task, participants needed to report whether they saw the target picture in 25% of trials, whereas in the high-frequency reporting task, participants needed to report whether they saw the target picture in each trial. Behavioral results showed that the hit rates were lower and false alarm rates were higher on reporting trials in low-frequency reporting tasks than on reporting trials in high-frequency reporting tasks. Unexpectedly, VAN was larger on reporting trials in the low-frequency reporting task than on reporting trials in the high-frequency reporting task. Importantly, our ERP results showed that LP was larger on reporting trials in the high-frequency reporting task than on reporting trials in the low-frequency reporting task. Thus, our findings indicated that when the frequency of reports was increased, the task relevance of the stimuli increased, which led to larger LP amplitudes. These findings suggest that LP correlates with subjective reports.
Collapse
Affiliation(s)
- Muwang Ye
- Academy of Psychology and Behavior, Faculty of Psychology, Tianjin Normal University, Tianjin, China; State Key Laboratory of Brain and Cognitive Sciences, CAS Center for Excellence in Brain Science and Intelligence Technology, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China.
| | - Anhui Wang
- Academy of Psychology and Behavior, Faculty of Psychology, Tianjin Normal University, Tianjin, China
| | - Haiyang Liang
- Academy of Psychology and Behavior, Faculty of Psychology, Tianjin Normal University, Tianjin, China
| | - Xiaowen Liu
- Academy of Psychology and Behavior, Faculty of Psychology, Tianjin Normal University, Tianjin, China
| |
Collapse
|
4
|
Dominik T, Mele A, Schurger A, Maoz U. Libet's legacy: A primer to the neuroscience of volition. Neurosci Biobehav Rev 2024; 157:105503. [PMID: 38072144 DOI: 10.1016/j.neubiorev.2023.105503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 11/09/2023] [Accepted: 12/04/2023] [Indexed: 12/23/2023]
Abstract
The neuroscience of volition is an emerging subfield of the brain sciences, with hundreds of papers on the role of consciousness in action formation published each year. This makes the state-of-the-art in the discipline poorly accessible to newcomers and difficult to follow even for experts in the field. Here we provide a comprehensive summary of research in this field since its inception that will be useful to both groups. We also discuss important ideas that have received little coverage in the literature so far. We systematically reviewed a set of 2220 publications, with detailed consideration of almost 500 of the most relevant papers. We provide a thorough introduction to the seminal work of Benjamin Libet from the 1960s to 1980s. We also discuss common criticisms of Libet's method, including temporal introspection, the interpretation of the assumed physiological correlates of volition, and various conceptual issues. We conclude with recent advances and potential future directions in the field, highlighting modern methodological approaches to volition, as well as important recent findings.
Collapse
Affiliation(s)
| | - Alfred Mele
- Department of Philosophy, Florida State University, FL, USA
| | | | - Uri Maoz
- Brain Institute, Chapman University, CA, USA
| |
Collapse
|
5
|
Sun B, Zeng X, Chen X, Zhao J, Fu S. Neural correlates of conscious processing of emotional faces: Evidence from event-related potentials. Neuropsychologia 2023; 182:108478. [PMID: 36707025 DOI: 10.1016/j.neuropsychologia.2023.108478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 12/26/2022] [Accepted: 01/05/2023] [Indexed: 01/25/2023]
Abstract
There is a theoretical debate between the early and late neural correlates of consciousness (NCCs). Previous studies using neutral face stimuli supported an early NCC and suggested that visual awareness negativity (VAN) is associated with consciousness, while late positivity (LP) reflects post-perceptual activity. However, emotional faces may help to examine the relationship between LP and consciousness due to the differences in late processing between emotional and neutral faces. To explore the effects of facial emotional information on NCCs, the present study manipulated consciousness with the inattentional blindness paradigm and used happy, fearful, and neutral faces as visual stimuli. The results showed that the conscious processing of emotional faces was correlated with VAN and LP, while the conscious processing of neutral faces was associated with VAN. First, the results suggest that VAN is an NCC, and the relationship between LP and consciousness is affected by facial emotional information. Second, VAN reflects the early perceptual experience of emotional faces, whereas LP may reflect the late conscious processing of emotional faces. Furthermore, source localization analysis showed that the LPs of emotional faces were mainly located in the frontal and parietal lobes, whereas those of neutral faces showed no significant activation. This suggests that facial emotional information may affect the brain regions associated with conscious processing. Time-frequency analysis showed that conscious processing is related to the enhancement of alpha and theta oscillation, indicating that conscious processing may be associated with the suppression of irrelevant stimuli. Overall, the present study suggests that the integration of the theories that support early and late NCCs helps explain the conscious processing of emotional faces.
Collapse
Affiliation(s)
- Bo Sun
- Department of Psychology and Center for Brain and Cognitive Sciences, School of Education, Guangzhou University, Guangzhou 510006, China.
| | - Xianqing Zeng
- Department of Psychology and Center for Brain and Cognitive Sciences, School of Education, Guangzhou University, Guangzhou 510006, China
| | - Xiaomin Chen
- Department of Psychology and Center for Brain and Cognitive Sciences, School of Education, Guangzhou University, Guangzhou 510006, China
| | - Jin Zhao
- Department of Psychology and Center for Brain and Cognitive Sciences, School of Education, Guangzhou University, Guangzhou 510006, China
| | - Shimin Fu
- Department of Psychology and Center for Brain and Cognitive Sciences, School of Education, Guangzhou University, Guangzhou 510006, China.
| |
Collapse
|
6
|
Bachmann T. Representational 'touch' and modulatory 'retouch'-two necessary neurobiological processes in thalamocortical interaction for conscious experience. Neurosci Conscious 2021; 2021:niab045. [PMID: 34925911 PMCID: PMC8672242 DOI: 10.1093/nc/niab045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 11/16/2021] [Accepted: 11/30/2021] [Indexed: 12/01/2022] Open
Abstract
Theories of consciousness using neurobiological data or being influenced by these data have been focused either on states of consciousness or contents of consciousness. These theories have occasionally used evidence from psychophysical phenomena where conscious experience is a dependent experimental variable. However, systematic catalog of many such relevant phenomena has not been offered in terms of these theories. In the perceptual retouch theory of thalamocortical interaction, recently developed to become a blend with the dendritic integration theory, consciousness states and contents of consciousness are explained by the same mechanism. This general-purpose mechanism has modulation of the cortical layer-5 pyramidal neurons that represent contents of consciousness as its core. As a surplus, many experimental psychophysical phenomena of conscious perception can be explained by the workings of this mechanism. Historical origins and current views inherent in this theory are presented and reviewed.
Collapse
Affiliation(s)
- Talis Bachmann
- Department of Penal Law, Laboratory of Cognitive Neuroscience, School of Law, University of Tartu (Tallinn Branch), Kaarli puiestee 3, Tallinn 10119, Estonia
| |
Collapse
|
7
|
Abraham A, Rutter B, Hermann C. Conceptual expansion via novel metaphor processing: An ERP replication and extension study examining individual differences in creativity. BRAIN AND LANGUAGE 2021; 221:105007. [PMID: 34416539 DOI: 10.1016/j.bandl.2021.105007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/15/2021] [Accepted: 08/06/2021] [Indexed: 06/13/2023]
Abstract
The aims of the present ERP study were twofold. First, to determine whether a previous study on creative cognition could be replicated, and second, to extend these findings by examining individual differences in creativity. Conceptual expansion, a capacity that is central to creativity, was induced via the processing of novel metaphors. Brain activity patterns in relation to these were compared to the processing of literal and nonsense phrases. The previous findings were replicated in that the N400, known for its sensitivity to semantic anomalies, indexed the originality of the phrases, while a post-N400 late component (LC), which is linked to semantic integration processes, indexed the appropriateness of the phrases. Moreover, only the LC was significantly sensitive to individual differences in creativity in the processing of these phrases. Differences at the level of semantic integration processes as well as the structure of knowledge organization are thereby implicated in individual differences in creativity.
Collapse
Affiliation(s)
- Anna Abraham
- Torrance Center for Creativity and Talent Development, Mary Frances Early College of Education, University of Georgia, Athens, GA, USA; Department of Educational Psychology, Mary Frances Early College of Education, University of Georgia, Athens, GA, USA.
| | - Barbara Rutter
- Department of Clinical Psychology, Justus Liebig University Giessen, Germany
| | - Christiane Hermann
- Department of Clinical Psychology, Justus Liebig University Giessen, Germany
| |
Collapse
|
8
|
Perceptual awareness negativity: a physiological correlate of sensory consciousness. Trends Cogn Sci 2021; 25:660-670. [PMID: 34172384 DOI: 10.1016/j.tics.2021.05.009] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/20/2021] [Accepted: 05/21/2021] [Indexed: 11/21/2022]
Abstract
Much research on the neural correlates of consciousness (NCC) has focused on two evoked potentials, the P3b and the visual or auditory awareness negativity (VAN, AAN). Surveying a broad range of recent experimental evidence, we find that repeated failures to observe the P3b during conscious perception eliminate it as a putative NCC. Neither the VAN nor the AAN have been dissociated from consciousness; furthermore, a similar neural signal correlates with tactile consciousness. These awareness negativities can be maximal contralateral to the evoking stimulus, are likely generated in underlying sensory cortices, and point to the existence of a generalized perceptual awareness negativity (PAN) reflecting the onset of sensory consciousness.
Collapse
|
9
|
Majchrowicz B, Wierzchoń M. Sensory attenuation of action outcomes of varying amplitude and valence. Conscious Cogn 2020; 87:103058. [PMID: 33278651 DOI: 10.1016/j.concog.2020.103058] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 11/13/2020] [Accepted: 11/19/2020] [Indexed: 01/23/2023]
Abstract
Stimuli caused by self-initiated actions are perceived as less intense than those caused externally; this effect is called sensory attenuation (SA). In two experiments, we aimed to assess the impact of the amplitude of outcomes and its affective valence on SA and explicit ratings of sense of agency. This allowed us to test the predictions of the available SA frameworks and better understand the link between SA, affect, and agency. The results indicated that SA can be reversed, and such sensory amplification is driven by low-amplitude and positive-valence outcomes. We also show that intentional action influences the perceived valence of outcomes, and that modulations of explicit sense of agency are divergent from those of SA. Our study shows that valence influences the processing of the amplitude of intentional action outcomes and suggests that none of the currently available frameworks give full justice to SA's variability.
Collapse
Affiliation(s)
- Bartosz Majchrowicz
- Consciousness Lab, Institute of Psychology, Jagiellonian University, Krakow, Poland.
| | - Michał Wierzchoń
- Consciousness Lab, Institute of Psychology, Jagiellonian University, Krakow, Poland
| |
Collapse
|
10
|
Doradzińska Ł, Wójcik MJ, Paź M, Nowicka MM, Nowicka A, Bola M. Unconscious perception of one's own name modulates amplitude of the P3B ERP component. Neuropsychologia 2020; 147:107564. [DOI: 10.1016/j.neuropsychologia.2020.107564] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 07/10/2020] [Accepted: 07/13/2020] [Indexed: 12/30/2022]
|
11
|
Glim S, Ries A, Sorg C, Wohlschläger AM. The temporal evolution of pre-stimulus slow cortical potentials is associated with an upcoming stimulus' access to visual consciousness. Conscious Cogn 2020; 84:102993. [PMID: 32771954 DOI: 10.1016/j.concog.2020.102993] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 07/28/2020] [Accepted: 07/28/2020] [Indexed: 01/21/2023]
Abstract
Slow cortical potentials (SCPs) have been proposed to be essential for the formation of conscious experience. To examine their temporal characteristics, we recorded electroencephalography during a visual backward-masking task, which required participants to localize the missing part of a target stimulus. A subsequent confidence rating was used as a proxy for the target's access to consciousness. Event-related potentials (ERPs) of all correct trials were determined relative to a brief period immediately before the target and then compared among consciousness levels. In an interval ranging from 2 s prior to target presentation up to this period, a negative relationship between slowly fluctuating ERP values and the level of consciousness became evident. After target presentation, high conscious awareness was characterized by an enhanced visual awareness negativity, an increased P3 component, and associated positive SCPs. Together, these findings add new evidence to the proposed role of SCPs in the emergence of visual consciousness.
Collapse
Affiliation(s)
- Sarah Glim
- Department of Neuroradiology, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675 Munich, Germany; TUM-Neuroimaging Center, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675 Munich, Germany; Graduate School of Systemic Neurosciences, LMU Munich, Großhaderner Str. 2, 82152 Planegg-Martinsried, Germany
| | - Anja Ries
- Department of Neuroradiology, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675 Munich, Germany; TUM-Neuroimaging Center, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675 Munich, Germany
| | - Christian Sorg
- Department of Neuroradiology, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675 Munich, Germany; TUM-Neuroimaging Center, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675 Munich, Germany; Department of Psychiatry, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675 Munich, Germany
| | - Afra M Wohlschläger
- Department of Neuroradiology, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675 Munich, Germany; TUM-Neuroimaging Center, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675 Munich, Germany; Graduate School of Systemic Neurosciences, LMU Munich, Großhaderner Str. 2, 82152 Planegg-Martinsried, Germany.
| |
Collapse
|
12
|
Abstract
It is proposed that the perceived present is not a moment in time, but an information structure comprising an integrated set of products of perceptual processing. All information in the perceived present carries an informational time marker identifying it as "present". This marker is exclusive to information in the perceived present. There are other kinds of time markers, such as ordinality ("this stimulus occurred before that one") and duration ("this stimulus lasted for 50 ms"). These are different from the "present" time marker and may be attached to information regardless of whether it is in the perceived present or not. It is proposed that the perceived present is a very short-term and very high-capacity holding area for perceptual information. The maximum holding time for any given piece of information is ~100 ms: This is affected by the need to balance the value of informational persistence for further processing against the problem of obsolescence of the information. The main function of the perceived present is to facilitate access by other specialized, automatic processes.
Collapse
Affiliation(s)
- Peter A White
- School of Psychology, Cardiff University, Tower Building, Park Place, Cardiff, Wales, CF10 3YG, UK.
| |
Collapse
|
13
|
Mazzi C, Mazzeo G, Savazzi S. Late Positivity Does Not Meet the Criteria to be Considered a Proper Neural Correlate of Perceptual Awareness. Front Syst Neurosci 2020; 14:36. [PMID: 32733211 PMCID: PMC7358964 DOI: 10.3389/fnsys.2020.00036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 05/18/2020] [Indexed: 11/19/2022] Open
Abstract
Contrastive analysis has been widely employed in the search for the electrophysiological neural correlates of consciousness. However, despite its clear logic, it has been argued that it may not succeed in isolating neural processes solely involved in the emergence of perceptual awareness. In fact, data from contrastive analysis would be contaminated by potential confounding factors reflecting distinct, though related, processes either preceding or following the conscious perception. At present, the ERP components representing the proper correlates of perceptual awareness still remain to be identified among those correlating with awareness (i.e., Visual Awareness Negativity, VAN and Late Positivity, LP). In order to dissociate visual awareness from post-perceptual confounds specifically related to decision making, we manipulated the response criterion, which affects how a percept is translated into a decision. In particular, while performing an orientation discrimination task, participants were asked to shift their response criterion across sessions. As a consequence, the resulting modulation should concern the ERP component(s) not exclusively reflecting mechanisms regulating the subjective conscious experience itself but rather the processes accompanying it. Electrophysiological results showed that N1 and P3 were sensitive to the response criterion adopted by participants. Additionally, the more the participants shifted their response criterion, the bigger the ERP modulation was; this was consequently indicative of the critical role of these components in the decision-making processes regardless of awareness level. When considering data independently from the response criterion, the aware vs. unaware contrast showed that both VAN and LP were significant. Crucially, the LP component was also modulated by the interaction of awareness and response criterion, while VAN results to be unaffected. In agreement with previous literature, these findings provide evidence supporting the hypothesis that VAN tracks the emergence of visual awareness by encoding the conscious percept, whereas LP reflects the contribution from post-perceptual processes related to response requirements. This excludes a direct functional role of this later component in giving rise to perceptual awareness.
Collapse
Affiliation(s)
- Chiara Mazzi
- Perception and Awareness (PandA) Laboratory, Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Gaetano Mazzeo
- Perception and Awareness (PandA) Laboratory, Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Silvia Savazzi
- Perception and Awareness (PandA) Laboratory, Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| |
Collapse
|
14
|
Bachmann T. Account of consciousness by Christof Koch: Review and questions. Conscious Cogn 2020; 82:102937. [PMID: 32388455 DOI: 10.1016/j.concog.2020.102937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 04/16/2020] [Accepted: 04/18/2020] [Indexed: 10/24/2022]
Abstract
This review is set to present the gist of the theoretical account of consciousness recently presented by Christof Koch and pose a couple of questions instigated by this account. The expected answers to these questions would hopefully help to advance our understanding of the basic nature of the conscious mind.
Collapse
Affiliation(s)
- Talis Bachmann
- Department of Penal Law, School of Law, University of Tartu (Tallinn Branch), Kaarli Puiestee 3, 10119 Tallinn, Estonia.
| |
Collapse
|
15
|
Förster J, Koivisto M, Revonsuo A. ERP and MEG correlates of visual consciousness: The second decade. Conscious Cogn 2020; 80:102917. [PMID: 32193077 DOI: 10.1016/j.concog.2020.102917] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 02/14/2020] [Accepted: 03/07/2020] [Indexed: 01/04/2023]
Abstract
The first decade of event-related potential (ERP) research had established that the most consistent correlates of the onset of visual consciousness are the early visual awareness negativity (VAN), a posterior negative component in the N2 time range, and the late positivity (LP), an anterior positive component in the P3 time range. Two earlier extensive reviews ten years ago had concluded that VAN is the earliest and most reliable correlate of visual phenomenal consciousness, whereas LP probably reflects later processes associated with reflective/access consciousness. This article provides an update to those earlier reviews. ERP and MEG studies that have appeared since 2010 and directly compared ERPs between aware and unaware conditions are reviewed, and important new developments in the field are discussed. The result corroborates VAN as the earliest and most consistent signature of visual phenomenal consciousness, and casts further doubt on LP as an ERP correlate of phenomenal consciousness.
Collapse
Affiliation(s)
- Jona Förster
- Division of Cognitive Neuroscience and Philosophy, University of Skövde, Sweden.
| | - Mika Koivisto
- Department of Psychology, University of Turku, Finland; Turku Brain and Mind Centre, University of Turku, Finland
| | - Antti Revonsuo
- Division of Cognitive Neuroscience and Philosophy, University of Skövde, Sweden; Department of Psychology, University of Turku, Finland; Turku Brain and Mind Centre, University of Turku, Finland
| |
Collapse
|
16
|
Derda M, Koculak M, Windey B, Gociewicz K, Wierzchoń M, Cleeremans A, Binder M. The role of levels of processing in disentangling the ERP signatures of conscious visual processing. Conscious Cogn 2019; 73:102767. [DOI: 10.1016/j.concog.2019.102767] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 06/13/2019] [Accepted: 06/13/2019] [Indexed: 10/26/2022]
|
17
|
Ye M, Lyu Y, Sclodnick B, Sun HJ. The P3 Reflects Awareness and Can Be Modulated by Confidence. Front Neurosci 2019; 13:510. [PMID: 31156381 PMCID: PMC6533851 DOI: 10.3389/fnins.2019.00510] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 05/02/2019] [Indexed: 12/30/2022] Open
Abstract
An important question in neural correlate of consciousness (NCC) studies is whether event-related potential (ERP) component P3 reflects visual awareness or the confidence with which one reports a visual experience. In the present study, participants detected visual stimuli presented at threshold-level contrast, then rated their subjective confidence with respect to their response on a four-point scale (very confident, quite confident, slightly confident, and not confident at all). Because awareness responses in trials with rating of “not confident at all” were likely noise, we analyzed the data excluding those trials. The ERP results revealed a significant positive difference in P3 amplitude between “aware” and “unaware” trials. P3 amplitude was more positive in aware trials compared to unaware trials. Importantly, this pattern was observed for trials with combined confidence ratings of “very confident” and “quite confident,” and for trials with confidence ratings of “slightly confident,” suggesting that awareness alone can modulate P3. A significant interaction between awareness and confidence is reported, suggesting that confidence influences P3 as well. In addition, ERP results revealed that visual awareness negativity (VAN) was observed over posterior temporal and occipital electrodes and largely not influenced by confidence. This result indicated that VAN is an early neural correlate of visual awareness.
Collapse
Affiliation(s)
- Muwang Ye
- Academy of Psychology and Behavior, Tianjin Normal University, Tianjin, China
| | - Yong Lyu
- Academy of Psychology and Behavior, Tianjin Normal University, Tianjin, China
| | - Ben Sclodnick
- Department of Psychology, Neuroscience & Behavior, McMaster University, Hamilton, ON, Canada
| | - Hong-Jin Sun
- Department of Psychology, Neuroscience & Behavior, McMaster University, Hamilton, ON, Canada
| |
Collapse
|
18
|
Ye M, Lyu Y. Later Positivity Reflects Post-perceptual Processes: Evidence From Immediate Detection and Delayed Detection Tasks. Front Psychol 2019; 10:82. [PMID: 30766499 PMCID: PMC6365435 DOI: 10.3389/fpsyg.2019.00082] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 01/11/2019] [Indexed: 11/24/2022] Open
Abstract
Electrophysiological recordings are usually used to study neural correlates of consciousness (NCCs). The aim of our present study was to use two detection tasks to dissociate the electrophysiological correlates of visual awareness from the post-perceptual processes. In immediate detection task, participants had to quickly report whether the stimulus was presented after stimulus, whereas in delayed detection task, participants had to put off reporting whether the stimulus was presented after stimulus. The results showed that two previously frequently observed electrophysiological NCCs were observed: visual awareness negativity (VAN) and later positivity (LP). Importantly, the amplitude of VAN over posterior temporal and occipital areas was not influenced by the task manipulation. However, the amplitude of LP over parietal, posterior temporal and occipital areas was influenced by the task manipulation during 650–850 ms. These data suggest that VAN is an early electrophysiological correlates of visual awareness, and LP reflects post-perceptual processes required in reporting perceptual awareness.
Collapse
Affiliation(s)
- Muwang Ye
- Academy of Psychology and Behavior, Tianjin Normal University, Tianjin, China
| | - Yong Lyu
- Academy of Psychology and Behavior, Tianjin Normal University, Tianjin, China
| |
Collapse
|
19
|
Spanlang B, Nierula B, Haffar M, Debruille JB. Mimicking Schizophrenia: Reducing P300b by Minimally Fragmenting Healthy Participants' Selves Using Immersive Virtual Reality Embodiment. Front Hum Neurosci 2019; 12:504. [PMID: 30662398 PMCID: PMC6328438 DOI: 10.3389/fnhum.2018.00504] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 12/03/2018] [Indexed: 11/13/2022] Open
Abstract
The most robust and clear biological index differentiating persons with schizophrenia from healthy controls is the drastic reduction of the amplitude of their P300b event-related brain potential (ERP). However, the cause of that reduction remains obscure. Nevertheless, the P300b belongs to the family of the late posterior positivities (LPPs) which are closely related to the consciousness of the meaning of the stimulus in the task for the participants themselves (e.g., the: I am seeing the target stimulus for which I have to respond). The fragmentation of the self present in schizophrenia, could thus be the cause. If this were true, then P300bs should be somewhat reduced in healthy participants when their self representations are temporarily and minimally fragmented. We tested this hypothesis by using the innocuous fragmentation of the self that occurs in virtual reality (VR). There, participants can have a fragment of their self in an avatar they feel embodied in, within a VR room, while having another fragment of their self in their real body in the real room where they know they are. Our participants were thus equipped with a head mounted display in which they viewed a virtual room where a female humanoid avatar was facing them. She was lifting her right hand in synchrony with the participants, in order to induce in them a feeling of embodiment. Stimuli were a frequent green- and a rare red-disk, the oddball stimulus, occurring over the right hand of the avatar. Participants had to perform a Go/NoGo task, lifting their right hand to the frequent green disk and repressing this action for the oddball red disk. In the syncMove block of trials the avatar was lifting her right hand synchronously with the participant, disturbing her self representation as confirmed by the debriefing session. In the noMove block, the avatar remained immobile. In the classic block, only the red and the green disk were displayed on a monochrome background, neither the room nor the avatar were shown. As predicted, P300bs were found to be smaller in the syncMove block than in the noMove- and the classic-block in participants who had the classically large P300b oddball effect between ERPs to the frequent and those to the rare stimuli. Reduced P300bs of schizophrenia could thus be partly due to self fragmentation. Results may also open an avenue of research to the functional significance of LPPs and the content of the consciousness indexed by these potentials.
Collapse
Affiliation(s)
- Bernhard Spanlang
- Event-Lab, Department of Clinical Psychology and Psychobiology, Universitat de Barcelona, Barcelona, Spain
| | - Birgit Nierula
- Event-Lab, Department of Clinical Psychology and Psychobiology, Universitat de Barcelona, Barcelona, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Maud Haffar
- Department of Neuroscience, McGill University, Montreal, QC, Canada
- Douglas Hospital Research Center, Montreal, QC, Canada
| | - J. Bruno Debruille
- Department of Neuroscience, McGill University, Montreal, QC, Canada
- Douglas Hospital Research Center, Montreal, QC, Canada
- Department of Psychiatry, McGill University, Montreal, QC, Canada
| |
Collapse
|
20
|
Bachmann T. On a Strategy of Advancement of TMS Based Methods for Studying NCC. Front Psychol 2018; 9:2026. [PMID: 30405502 PMCID: PMC6206045 DOI: 10.3389/fpsyg.2018.02026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 10/02/2018] [Indexed: 11/14/2022] Open
|
21
|
Bachmann T. Visual masking: Contributions from and comments on Bruce Bridgeman. Conscious Cogn 2018; 64:13-18. [DOI: 10.1016/j.concog.2018.04.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 03/26/2018] [Accepted: 04/24/2018] [Indexed: 10/17/2022]
|
22
|
Key B, Brown D. Designing Brains for Pain: Human to Mollusc. Front Physiol 2018; 9:1027. [PMID: 30127750 PMCID: PMC6088194 DOI: 10.3389/fphys.2018.01027] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 07/11/2018] [Indexed: 12/16/2022] Open
Abstract
There is compelling evidence that the "what it feels like" subjective experience of sensory stimuli arises in the cerebral cortex in both humans as well as mammalian experimental animal models. Humans are alone in their ability to verbally communicate their experience of the external environment. In other species, sensory awareness is extrapolated on the basis of behavioral indicators. For instance, cephalopods have been claimed to be sentient on the basis of their complex behavior and anecdotal reports of human-like intelligence. We have interrogated the findings of avoidance learning behavioral paradigms and classical brain lesion studies and conclude that there is no evidence for cephalopods feeling pain. This analysis highlighted the questionable nature of anthropometric assumptions about sensory experience with increased phylogenetic distance from humans. We contend that understanding whether invertebrates such as molluscs are sentient should first begin with defining the computational processes and neural circuitries underpinning subjective awareness. Using fundamental design principles, we advance the notion that subjective awareness is dependent on observer neural networks (networks that in some sense introspect the neural processing generating neural representations of sensory stimuli). This introspective process allows the observer network to create an internal model that predicts the neural processing taking place in the network being surveyed. Predictions arising from the internal model form the basis of a rudimentary form of awareness. We develop an algorithm built on parallel observer networks that generates multiple levels of sensory awareness. A network of cortical regions in the human brain has the appropriate functional properties and neural interconnectivity that is consistent with the predicted circuitry of the algorithm generating pain awareness. By contrast, the cephalopod brain lacks the necessary neural circuitry to implement such an algorithm. In conclusion, we find no compelling behavioral, functional, or neuroanatomical evidence to indicate that cephalopods feel pain.
Collapse
Affiliation(s)
- Brian Key
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
| | - Deborah Brown
- School of Historical and Philosophical Inquiry, University of Queensland, Brisbane, QLD, Australia
| |
Collapse
|