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Rürup L, Mathes B, Schmiedt-Fehr C, Wienke AS, Özerdem A, Brand A, Basar-Eroglu C. Altered gamma and theta oscillations during multistable perception in schizophrenia. Int J Psychophysiol 2020; 155:127-139. [DOI: 10.1016/j.ijpsycho.2020.06.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 06/01/2020] [Accepted: 06/05/2020] [Indexed: 12/24/2022]
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Wimmer MC, Marx C, Stirk S, Hancock PJB. Bilinguals' inhibitory control and attentional processes in a visual perceptual task. PSYCHOLOGICAL RESEARCH 2020; 85:1439-1448. [PMID: 32382882 DOI: 10.1007/s00426-020-01333-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 03/27/2020] [Indexed: 12/01/2022]
Abstract
The aim was to examine theories of bilingual inhibitory control superiority in the visual domain. In an ambiguous figure task, the ability to reverse (switch) interpretations (e.g., duck-rabbit) was examined in 3-5-year-olds bilinguals and monolinguals (N = 67). Bilingualism was no performance predictor in conceptual tasks (Droodle task, false belief task, ambiguous figures production task) that did not pose inhibitory demands. Bilinguals outperformed monolinguals in the ability to reverse, suggesting superior inhibitory capacity per se. Once reversal was experienced there was no difference in the time it took to reverse or reversal frequency between bilinguals and monolinguals. Bayesian analyses confirmed statistical result patterns. Findings support the established view of bilinguals' superior domain-general inhibitory control. This might be brought to bear by attending the environment differently.
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Affiliation(s)
- Marina C Wimmer
- Department of Psychology, Edinburgh Napier University, Edinburgh, EH11 4DY, UK.
| | - Christina Marx
- Department of Psychology, University of Salzburg, 5020, Salzburg, Austria
| | - Steven Stirk
- School of Psychology, University of Plymouth, Plymouth, PL4 8AA, UK
| | - Peter J B Hancock
- Psychology, Faculty of Natural Sciences, University of Stirling, Stirling, FK9 4LA, UK
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Taranu M, Wimmer MC, Ross J, Farkas D, van Ee R, Winkler I, Denham SL. Children's perception of visual and auditory ambiguity and its link to executive functions and creativity. J Exp Child Psychol 2019; 184:123-138. [PMID: 31029832 DOI: 10.1016/j.jecp.2019.03.010] [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: 10/03/2018] [Revised: 03/25/2019] [Accepted: 03/26/2019] [Indexed: 10/26/2022]
Abstract
The phenomenon of perceptual bistability provides insights into aspects of perceptual processing not normally accessible to everyday experience. However, most experiments have been conducted in adults, and it is not clear to what extent key aspects of perceptual switching change through development. The current research examined the ability of 6-, 8-, and 10-year-old children (N = 66) to switch between competing percepts of ambiguous visual and auditory stimuli and links between switching rate, executive functions, and creativity. The numbers of switches participants reported in two visual tasks (ambiguous figure and ambiguous structure from motion) and two auditory tasks (verbal transformation and auditory streaming) were measured in three 60-s blocks. In addition, inhibitory control was measured with a Stroop task, set shifting was measured with a verbal fluency task, and creativity was measured with a divergent thinking task. The numbers of perceptual switches increased in all four tasks from 6 to 10 years of age but differed across tasks in that they were higher in the verbal transformation and ambigous structure-from-motion tasks than in the ambigous figure and auditory streaming tasks for all age groups. Although perceptual switching rates differed across tasks, there were predictive relationships between switching rates in some tasks. However, little evidence for the influence of central processes on perceptual switching was found. Overall, the results support the notion that perceptual switching is largely modality and task specific and that this property is already evident when perceptual switching emerges.
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Affiliation(s)
- Mihaela Taranu
- Cognition Institute and School of Psychology, University of Plymouth, Plymouth PL4 8AA, UK
| | - Marina C Wimmer
- Cognition Institute and School of Psychology, University of Plymouth, Plymouth PL4 8AA, UK.
| | - Josephine Ross
- Psychology, School of Social Sciences, University of Dundee, Nethergate, Dundee DD1 4HN, Scotland, UK
| | - Dávid Farkas
- Institute of Cognitive Neuroscience and Psychology, Research Centre of Natural Sciences, Hungarian Academy of Sciences, H-1117 Budapest, Hungary
| | - Raymond van Ee
- Biophysics, Donders Institute for Brain, Cognition and Behavior, Radboud University, 6500 GL Nijmegen, The Netherlands; Department of Brain and Cognition, Leuven University, 3000 BE Leuven, Belgium; Department of Brain, Behavior and Cognition, Philips Research, High Tech Campus, 5656 AE Eindhoven, The Netherlands
| | - István Winkler
- Department of Cognitive Science, Faculty of Natural Sciences, Budapest University of Technology and Economics, H-1111 Budapest, Hungary
| | - Susan L Denham
- Cognition Institute and School of Psychology, University of Plymouth, Plymouth PL4 8AA, UK
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Rodríguez-Martínez GA, Castillo-Parra H. Bistable perception: neural bases and usefulness in psychological research. Int J Psychol Res (Medellin) 2018; 11:63-76. [PMID: 32612780 PMCID: PMC7110285 DOI: 10.21500/20112084.3375] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Bistable images have the possibility of being perceived in two different ways. Due to their physical characteristics, these visual stimuli allow two different perceptions, associated with top-down and bottom-up modulating processes. Based on an extensive literature review, the present article aims to gather the conceptual models and the foundations of perceptual bistability. This theoretical article compiles not only notions that are intertwined with the understanding of this perceptual phenomenon, but also the diverse classification and uses of bistable images in psychological research, along with a detailed explanation of the neural correlates that are involved in perceptual reversibility. We conclude that the use of bistable images as a paradigmatic resource in psychological research might be extensive. In addition, due to their characteristics, visual bistable stimuli have the potential to be implemented as a resource in experimental tasks that seek to understand diverse concerns linked essentially to attention, sensory, perceptual and memory processes.
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Affiliation(s)
- Guillermo Andrés Rodríguez-Martínez
- Escuela de Publicidad - Universidad de Bogotá Jorge Tadeo Lozano, Bogotá, Colombia. Universidad de Bogotá Jorge Tadeo Lozano Universidad de Bogotá Jorge Tadeo Lozano Bogotá Colombia.,Facultad de Psicología - Universidad de San Buenaventura de Medellín, Colombia. Universidad de San Buenaventura Universidad de San Buenaventura de Medellín Colombia
| | - Henry Castillo-Parra
- Facultad de Psicología - Universidad de San Buenaventura de Medellín, Colombia. Universidad de San Buenaventura Universidad de San Buenaventura de Medellín Colombia
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Zhao Y, Tang J, Cao Y, Jiao X, Xu M, Zhou P, Ming D, Qi H. Effects of Distracting Task with Different Mental Workload on Steady-State Visual Evoked Potential Based Brain Computer Interfaces-an Offline Study. Front Neurosci 2018; 12:79. [PMID: 29497360 PMCID: PMC5818426 DOI: 10.3389/fnins.2018.00079] [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: 03/17/2017] [Accepted: 01/31/2018] [Indexed: 11/30/2022] Open
Abstract
Brain-computer interfaces (BCIs), independent of the brain's normal output pathways, are attracting an increasing amount of attention as devices that extract neural information. As a typical type of BCI system, the steady-state visual evoked potential (SSVEP)-based BCIs possess a high signal-to-noise ratio and information transfer rate. However, the current high speed SSVEP-BCIs were implemented with subjects concentrating on stimuli, and intentionally avoided additional tasks as distractors. This paper aimed to investigate how a distracting simultaneous task, a verbal n-back task with different mental workload, would affect the performance of SSVEP-BCI. The results from fifteen subjects revealed that the recognition accuracy of SSVEP-BCI was significantly impaired by the distracting task, especially under a high mental workload. The average classification accuracy across all subjects dropped by 8.67% at most from 1- to 4-back, and there was a significant negative correlation (maximum r = −0.48, p < 0.001) between accuracy and subjective mental workload evaluation of the distracting task. This study suggests a potential hindrance for the SSVEP-BCI daily use, and then improvements should be investigated in the future studies.
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Affiliation(s)
- Yawei Zhao
- Department of Biomedical Engineering, College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin, China
| | - Jiabei Tang
- Department of Biomedical Engineering, College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin, China
| | - Yong Cao
- National Key Laboratory of Human Factors Engineering, China Astronaut Research and Training Center, Beijing, China
| | - Xuejun Jiao
- National Key Laboratory of Human Factors Engineering, China Astronaut Research and Training Center, Beijing, China
| | - Minpeng Xu
- Department of Biomedical Engineering, College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin, China
| | - Peng Zhou
- Department of Biomedical Engineering, College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin, China
| | - Dong Ming
- Department of Biomedical Engineering, College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin, China
| | - Hongzhi Qi
- Department of Biomedical Engineering, College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin, China
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Juxtaposing the real-time unfolding of subjective experience and ERP neuromarker dynamics. Conscious Cogn 2017; 54:3-19. [DOI: 10.1016/j.concog.2017.05.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 05/10/2017] [Accepted: 05/11/2017] [Indexed: 01/08/2023]
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Díaz-Santos M, Mauro S, Cao B, Yazdanbakhsh A, Neargarder S, Cronin-Golomb A. Bistable perception in normal aging: perceptual reversibility and its relation to cognition. AGING NEUROPSYCHOLOGY AND COGNITION 2016; 24:115-134. [PMID: 27116194 DOI: 10.1080/13825585.2016.1173646] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The effects of age on the ability to resolve perceptual ambiguity are unknown, though it depends on frontoparietal attentional networks known to change with age. We presented the bistable Necker cube to 24 middle-aged and OAs (older adults; 56-78 years) and 20 YAs (younger adults; 18-24 years) under passive-viewing and volitional control conditions: Hold one cube percept and Switch between cube percepts. During passive viewing, OAs had longer dominance durations (time spent on each percept) than YAs. In the Hold condition, OAs were less able than YAs to increase dominance durations. In the Switch condition, OAs and YAs did not differ in performance. Dominance durations in either condition correlated with performance on tests of executive function mediated by the frontal lobes. Eye movements (fixation deviations) did not differ between groups. These results suggest that OAs' reduced ability to hold a percept may arise from reduced selective attention. The lack of correlation of performance between Hold and executive-function measures suggests at least a partial segregation of underlying mechanisms.
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Affiliation(s)
- Mirella Díaz-Santos
- a Department of Psychological and Brain Sciences , Boston University , Boston , MA , USA
| | - Samantha Mauro
- a Department of Psychological and Brain Sciences , Boston University , Boston , MA , USA
| | - Bo Cao
- b Center for Computational Neuroscience and Neural Technology , Boston University , Boston , MA , USA
| | - Arash Yazdanbakhsh
- b Center for Computational Neuroscience and Neural Technology , Boston University , Boston , MA , USA
| | - Sandy Neargarder
- a Department of Psychological and Brain Sciences , Boston University , Boston , MA , USA.,c Department of Psychology , Hart Hall, Bridgewater State University , Bridgewater , MA , USA
| | - Alice Cronin-Golomb
- a Department of Psychological and Brain Sciences , Boston University , Boston , MA , USA
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Multistable Perception in Older Adults: Constructing a Whole from Fragments. Brain Sci 2016; 6:brainsci6010010. [PMID: 27011204 PMCID: PMC4810180 DOI: 10.3390/brainsci6010010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 03/07/2016] [Accepted: 03/15/2016] [Indexed: 11/23/2022] Open
Abstract
Visual perception is constructive in nature; that is, a coherent whole is generated from ambiguous fragments that are encountered in dynamic visual scenes. Creating this coherent whole from fragmented sensory inputs requires one to detect, identify, distinguish and organize sensory input. The organization of fragments into a coherent whole is facilitated by the continuous interactions between lower level sensory inputs and higher order processes. However, age-related declines are found in both neural structures and cognitive processes (e.g., attention and inhibition). The impact of these declines on the constructive nature of visual processing was the focus of this study. Here we asked younger adults, young-old (65–79 years), and old-old adults (80+ years) to view a multistable figure (i.e., Necker cube) under four conditions (free, priming, volition, and adaptation) and report, via a button press, when percepts spontaneously changed. The oldest-olds, unlike young-olds and younger adults, were influenced by priming, had less visual stability during volition and showed less ability to adapt to multistable stimuli. These results suggest that the ability to construct a coherent whole from fragments declines with age. More specifically, vision is constructed differently in the old-olds, which might influence environmental interpretations and navigational abilities in this age group.
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Johannesen JK, Bi J, Jiang R, Kenney JG, Chen CMA. Machine learning identification of EEG features predicting working memory performance in schizophrenia and healthy adults. ACTA ACUST UNITED AC 2016; 2:3. [PMID: 27375854 PMCID: PMC4928381 DOI: 10.1186/s40810-016-0017-0] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Background With millisecond-level resolution, electroencephalographic (EEG) recording provides a sensitive tool to assay neural dynamics of human cognition. However, selection of EEG features used to answer experimental questions is typically determined a priori. The utility of machine learning was investigated as a computational framework for extracting the most relevant features from EEG data empirically. Methods Schizophrenia (SZ; n = 40) and healthy community (HC; n = 12) subjects completed a Sternberg Working Memory Task (SWMT) during EEG recording. EEG was analyzed to extract 5 frequency components (theta1, theta2, alpha, beta, gamma) at 4 processing stages (baseline, encoding, retention, retrieval) and 3 scalp sites (frontal-Fz, central-Cz, occipital-Oz) separately for correctly and incorrectly answered trials. The 1-norm support vector machine (SVM) method was used to build EEG classifiers of SWMT trial accuracy (correct vs. incorrect; Model 1) and diagnosis (HC vs. SZ; Model 2). External validity of SVM models was examined in relation to neuropsychological test performance and diagnostic classification using conventional regression-based analyses. Results SWMT performance was significantly reduced in SZ (p < .001). Model 1 correctly classified trial accuracy at 84 % in HC, and at 74 % when cross-validated in SZ data. Frontal gamma at encoding and central theta at retention provided highest weightings, accounting for 76 % of variance in SWMT scores and 42 % variance in neuropsychological test performance across samples. Model 2 identified frontal theta at baseline and frontal alpha during retrieval as primary classifiers of diagnosis, providing 87 % classification accuracy as a discriminant function. Conclusions EEG features derived by SVM are consistent with literature reports of gamma’s role in memory encoding, engagement of theta during memory retention, and elevated resting low-frequency activity in schizophrenia. Tests of model performance and cross-validation support the stability and generalizability of results, and utility of SVM as an analytic approach for EEG feature selection.
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Affiliation(s)
- Jason K Johannesen
- VA Connecticut Healthcare System, Psychology Service, 116-B, 950 Campbell Ave, West Haven, CT 06516, USA; Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Jinbo Bi
- Computer Science and Engineering, University of Connecticut, Storrs, CT, USA
| | - Ruhua Jiang
- Computer Science and Engineering, University of Connecticut, Storrs, CT, USA
| | - Joshua G Kenney
- VA Connecticut Healthcare System, Psychology Service, 116-B, 950 Campbell Ave, West Haven, CT 06516, USA; Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Chi-Ming A Chen
- Psychological Sciences, University of Connecticut, Storrs, CT, USA
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Ke Y, Wang P, Chen Y, Gu B, Qi H, Zhou P, Ming D. Training and testing ERP-BCIs under different mental workload conditions. J Neural Eng 2015; 13:016007. [PMID: 26655346 DOI: 10.1088/1741-2560/13/1/016007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE As one of the most popular and extensively studied paradigms of brain-computer interfaces (BCIs), event-related potential-based BCIs (ERP-BCIs) are usually built and tested in ideal laboratory settings in most existing studies, with subjects concentrating on stimuli and intentionally avoiding possible distractors. This study is aimed at examining the effect of simultaneous mental activities on ERP-BCIs by manipulating various levels of mental workload during the training and/or testing of an ERP-BCI. APPROACH Mental workload was manipulated during the training or testing of a row-column P300-speller to investigate how and to what extent the spelling performance and the ERPs evoked by the oddball stimuli are affected by simultaneous mental workload. MAIN RESULTS Responses of certain ERP components, temporal-occipital N200 and the late reorienting negativity evoked by the oddball stimuli and the classifiability of ERP features between targets and non-targets decreased with the increase of mental workload encountered by the subject. However, the effect of mental workload on the performance of ERP-BCI was not always negative but depended on the conditions where the ERP-BCI was built and applied. The performance of ERP-BCI built under an ideal lab setting without any irrelevant mental activities declined with the increasing mental workload of the testing data. However, the performance was significantly improved when an ERP-BCI was built under an appropriate mental workload level, compared to that built under speller-only conditions. SIGNIFICANCE The adverse effect of concurrent mental activities may present a challenge for ERP-BCIs trained in ideal lab settings but which are to be used in daily work, especially when users are performing demanding mental processing. On the other hand, the positive effects of the mental workload of the training data suggest that introducing appropriate mental workload during training ERP-BCIs is of potential benefit to the performance in practical applications.
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Díaz-Santos M, Cao B, Mauro SA, Yazdanbakhsh A, Neargarder S, Cronin-Golomb A. Effect of visual cues on the resolution of perceptual ambiguity in Parkinson's disease and normal aging. J Int Neuropsychol Soc 2015; 21:146-55. [PMID: 25765890 PMCID: PMC5433847 DOI: 10.1017/s1355617715000065] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Parkinson's disease (PD) and normal aging have been associated with changes in visual perception, including reliance on external cues to guide behavior. This raises the question of the extent to which these groups use visual cues when disambiguating information. Twenty-seven individuals with PD, 23 normal control adults (NC), and 20 younger adults (YA) were presented a Necker cube in which one face was highlighted by thickening the lines defining the face. The hypothesis was that the visual cues would help PD and NC to exert better control over bistable perception. There were three conditions, including passive viewing and two volitional-control conditions (hold one percept in front; and switch: speed up the alternation between the two). In the Hold condition, the cue was either consistent or inconsistent with task instructions. Mean dominance durations (time spent on each percept) under passive viewing were comparable in PD and NC, and shorter in YA. PD and YA increased dominance durations in the Hold cue-consistent condition relative to NC, meaning that appropriate cues helped PD but not NC hold one perceptual interpretation. By contrast, in the Switch condition, NC and YA decreased dominance durations relative to PD, meaning that the use of cues helped NC but not PD in expediting the switch between percepts. Provision of low-level cues has effects on volitional control in PD that are different from in normal aging, and only under task-specific conditions does the use of such cues facilitate the resolution of perceptual ambiguity.
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Affiliation(s)
- Mirella Díaz-Santos
- Department of Psychological and Brain Sciences, Boston University, Boston, Massachusetts
| | - Bo Cao
- Center for Computational Neuroscience and Neural Technology, Boston University, Boston, Massachusetts
| | - Samantha A. Mauro
- Department of Psychological and Brain Sciences, Boston University, Boston, Massachusetts
| | - Arash Yazdanbakhsh
- Center for Computational Neuroscience and Neural Technology, Boston University, Boston, Massachusetts
| | - Sandy Neargarder
- Department of Psychological and Brain Sciences, Boston University, Boston, Massachusetts
- Department of Psychology, Hart Hall, Bridgewater State University, Bridgewater, Massachusetts
| | - Alice Cronin-Golomb
- Department of Psychological and Brain Sciences, Boston University, Boston, Massachusetts
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Mathes B, Khalaidovski K, Schmiedt-Fehr C, Basar-Eroglu C. Frontal theta activity is pronounced during illusory perception. Int J Psychophysiol 2014; 94:445-54. [DOI: 10.1016/j.ijpsycho.2014.08.585] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 08/14/2014] [Accepted: 08/18/2014] [Indexed: 10/24/2022]
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Bachmann T, Hudetz AG. It is time to combine the two main traditions in the research on the neural correlates of consciousness: C = L × D. Front Psychol 2014; 5:940. [PMID: 25202297 PMCID: PMC4141455 DOI: 10.3389/fpsyg.2014.00940] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 08/06/2014] [Indexed: 01/08/2023] Open
Abstract
Research on neural correlates of consciousness has been conducted and carried out mostly from within two relatively autonomous paradigmatic traditions – studying the specific contents of conscious experience and their brain-process correlates and studying the level of consciousness. In the present paper we offer a theoretical integration suggesting that an emphasis has to be put on understanding the mechanisms of consciousness (and not a mere correlates) and in doing this, the two paradigmatic traditions must be combined. We argue that consciousness emerges as a result of interaction of brain mechanisms specialized for representing the specific contents of perception/cognition – the data – and mechanisms specialized for regulating the level of activity of whatever data the content-carrying specific mechanisms happen to represent. Each of these mechanisms are necessary because without the contents there is no conscious experience and without the required level of activity the processed contents remain unconscious. Together the two mechanisms, when activated up to a necessary degree each, provide conditions sufficient for conscious experience to emerge. This proposal is related to pertinent experimental evidence.
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Davidson GD, Pitts MA. Auditory event-related potentials associated with perceptual reversals of bistable pitch motion. Front Hum Neurosci 2014; 8:572. [PMID: 25152722 PMCID: PMC4126364 DOI: 10.3389/fnhum.2014.00572] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2014] [Accepted: 07/14/2014] [Indexed: 11/21/2022] Open
Abstract
Previous event-related potential (ERP) experiments have consistently identified two components associated with perceptual transitions of bistable visual stimuli, the "reversal negativity" (RN) and the "late positive complex" (LPC). The RN (~200 ms post-stimulus, bilateral occipital-parietal distribution) is thought to reflect transitions between neural representations that form the moment-to-moment contents of conscious perception, while the LPC (~400 ms, central-parietal) is considered an index of post-perceptual processing related to accessing and reporting one's percept. To explore the generality of these components across sensory modalities, the present experiment utilized a novel bistable auditory stimulus. Pairs of complex tones with ambiguous pitch relationships were presented sequentially while subjects reported whether they perceived the tone pairs as ascending or descending in pitch. ERPs elicited by the tones were compared according to whether perceived pitch motion changed direction or remained the same across successive trials. An auditory reversal negativity (aRN) component was evident at ~170 ms post-stimulus over bilateral fronto-central scalp locations. An auditory LPC component (aLPC) was evident at subsequent latencies (~350 ms, fronto-central distribution). These two components may be auditory analogs of the visual RN and LPC, suggesting functionally equivalent but anatomically distinct processes in auditory vs. visual bistable perception.
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