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Akdogan I, Ogmen H, Kafaligonul H. The phase coherence of cortical oscillations predicts dynamic changes in perceived visibility. Cereb Cortex 2024; 34:bhae380. [PMID: 39319441 PMCID: PMC11422671 DOI: 10.1093/cercor/bhae380] [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: 05/22/2024] [Revised: 08/28/2024] [Accepted: 09/03/2024] [Indexed: 09/26/2024] Open
Abstract
The phase synchronization of brain oscillations plays an important role in visual processing, perceptual awareness, and performance. Yet, the cortical mechanisms underlying modulatory effects of post-stimulus phase coherence and frequency-specific oscillations associated with different aspects of vision are still subject to debate. In this study, we aimed to identify the post-stimulus phase coherence of cortical oscillations associated with perceived visibility and contour discrimination. We analyzed electroencephalogram data from two masking experiments where target visibility was manipulated by the contrast ratio or polarity of the mask under various onset timing conditions (stimulus onset asynchronies, SOAs). The behavioral results indicated an SOA-dependent suppression of target visibility due to masking. The time-frequency analyses revealed significant modulations of phase coherence over occipital and parieto-occipital regions. We particularly identified modulations of phase coherence in the (i) 2-5 Hz frequency range, which may reflect feedforward-mediated contour detection and sustained visibility; and (ii) 10-25 Hz frequency range, which may be associated with suppressed visibility through inhibitory interactions between and within synchronized neural pathways. Taken together, our findings provide evidence that oscillatory phase alignments, not only in the pre-stimulus but also in the post-stimulus window, play a crucial role in shaping perceived visibility and dynamic vision.
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Affiliation(s)
- Irem Akdogan
- Department of Neuroscience, Bilkent University, Cankaya, Ankara 06800, Türkiye
- Aysel Sabuncu Brain Research Center, Bilkent University, Cankaya, Ankara 06800, Türkiye
- National Magnetic Resonance Research Center (UMRAM), Bilkent University, Cankaya, Ankara 06800, Türkiye
| | - Haluk Ogmen
- Laboratory of Perceptual and Cognitive Dynamics, Electrical & Computer Engineering, Ritchie School of Engineering & Computer Science, University of Denver, Denver, CO 80210, United States
| | - Hulusi Kafaligonul
- Department of Neuroscience, Bilkent University, Cankaya, Ankara 06800, Türkiye
- Aysel Sabuncu Brain Research Center, Bilkent University, Cankaya, Ankara 06800, Türkiye
- National Magnetic Resonance Research Center (UMRAM), Bilkent University, Cankaya, Ankara 06800, Türkiye
- Neuroscience and Neurotechnology Center of Excellence (NÖROM), Faculty of Medicine, Gazi University, Yenimahalle, Ankara 06560, Türkiye
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2
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Senkowski D, Engel AK. Multi-timescale neural dynamics for multisensory integration. Nat Rev Neurosci 2024; 25:625-642. [PMID: 39090214 DOI: 10.1038/s41583-024-00845-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/02/2024] [Indexed: 08/04/2024]
Abstract
Carrying out any everyday task, be it driving in traffic, conversing with friends or playing basketball, requires rapid selection, integration and segregation of stimuli from different sensory modalities. At present, even the most advanced artificial intelligence-based systems are unable to replicate the multisensory processes that the human brain routinely performs, but how neural circuits in the brain carry out these processes is still not well understood. In this Perspective, we discuss recent findings that shed fresh light on the oscillatory neural mechanisms that mediate multisensory integration (MI), including power modulations, phase resetting, phase-amplitude coupling and dynamic functional connectivity. We then consider studies that also suggest multi-timescale dynamics in intrinsic ongoing neural activity and during stimulus-driven bottom-up and cognitive top-down neural network processing in the context of MI. We propose a new concept of MI that emphasizes the critical role of neural dynamics at multiple timescales within and across brain networks, enabling the simultaneous integration, segregation, hierarchical structuring and selection of information in different time windows. To highlight predictions from our multi-timescale concept of MI, real-world scenarios in which multi-timescale processes may coordinate MI in a flexible and adaptive manner are considered.
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Affiliation(s)
- Daniel Senkowski
- Department of Psychiatry and Neurosciences, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Andreas K Engel
- Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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3
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Black T, Jenkins BW, Laprairie RB, Howland JG. Therapeutic potential of gamma entrainment using sensory stimulation for cognitive symptoms associated with schizophrenia. Neurosci Biobehav Rev 2024; 161:105681. [PMID: 38641090 DOI: 10.1016/j.neubiorev.2024.105681] [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: 01/25/2024] [Revised: 03/27/2024] [Accepted: 04/16/2024] [Indexed: 04/21/2024]
Abstract
Schizophrenia is a complex neuropsychiatric disorder with significant morbidity. Treatment options that address the spectrum of symptoms are limited, highlighting the need for innovative therapeutic approaches. Gamma Entrainment Using Sensory Stimulation (GENUS) is an emerging treatment for neuropsychiatric disorders that uses sensory stimulation to entrain impaired oscillatory network activity and restore brain function. Aberrant oscillatory activity often underlies the symptoms experienced by patients with schizophrenia. We propose that GENUS has therapeutic potential for schizophrenia. This paper reviews the current status of schizophrenia treatment and explores the use of sensory stimulation as an adjunctive treatment, specifically through gamma entrainment. Impaired gamma frequency entrainment is observed in patients, particularly in response to auditory and visual stimuli. Thus, sensory stimulation, such as music listening, may have therapeutic potential for individuals with schizophrenia. GENUS holds novel therapeutic potential to improve the lives of individuals with schizophrenia, but further research is required to determine the efficacy of GENUS, optimize its delivery and therapeutic window, and develop strategies for its implementation in specific patient populations.
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Affiliation(s)
- Tallan Black
- College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, SK, Canada.
| | - Bryan W Jenkins
- Division of Behavioral Biology, Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Robert B Laprairie
- College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, SK, Canada; Department of Pharmacology, College of Medicine, Dalhousie University, Halifax, NS, Canada
| | - John G Howland
- Department of Anatomy, Physiology, and Pharmacology, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada
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Batterink LJ, Mulgrew J, Gibbings A. Rhythmically Modulating Neural Entrainment during Exposure to Regularities Influences Statistical Learning. J Cogn Neurosci 2024; 36:107-127. [PMID: 37902580 DOI: 10.1162/jocn_a_02079] [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: 10/31/2023]
Abstract
The ability to discover regularities in the environment, such as syllable patterns in speech, is known as statistical learning. Previous studies have shown that statistical learning is accompanied by neural entrainment, in which neural activity temporally aligns with repeating patterns over time. However, it is unclear whether these rhythmic neural dynamics play a functional role in statistical learning or whether they largely reflect the downstream consequences of learning, such as the enhanced perception of learned words in speech. To better understand this issue, we manipulated participants' neural entrainment during statistical learning using continuous rhythmic visual stimulation. Participants were exposed to a speech stream of repeating nonsense words while viewing either (1) a visual stimulus with a "congruent" rhythm that aligned with the word structure, (2) a visual stimulus with an incongruent rhythm, or (3) a static visual stimulus. Statistical learning was subsequently measured using both an explicit and implicit test. Participants in the congruent condition showed a significant increase in neural entrainment over auditory regions at the relevant word frequency, over and above effects of passive volume conduction, indicating that visual stimulation successfully altered neural entrainment within relevant neural substrates. Critically, during the subsequent implicit test, participants in the congruent condition showed an enhanced ability to predict upcoming syllables and stronger neural phase synchronization to component words, suggesting that they had gained greater sensitivity to the statistical structure of the speech stream relative to the incongruent and static groups. This learning benefit could not be attributed to strategic processes, as participants were largely unaware of the contingencies between the visual stimulation and embedded words. These results indicate that manipulating neural entrainment during exposure to regularities influences statistical learning outcomes, suggesting that neural entrainment may functionally contribute to statistical learning. Our findings encourage future studies using non-invasive brain stimulation methods to further understand the role of entrainment in statistical learning.
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Pomper U. No evidence for tactile entrainment of attention. Front Psychol 2023; 14:1168428. [PMID: 37303888 PMCID: PMC10250593 DOI: 10.3389/fpsyg.2023.1168428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 05/11/2023] [Indexed: 06/13/2023] Open
Abstract
Temporal patterns in our environment provide a rich source of information, to which endogenous neural processes linked to perception and attention can synchronize. This phenomenon, known as entrainment, has so far been studied predominately in the visual and auditory domains. It is currently unknown whether sensory phase-entrainment generalizes to the tactile modality, e.g., for the perception of surface patterns or when reading braille. Here, we address this open question via a behavioral experiment with preregistered experimental and analysis protocols. Twenty healthy participants were presented, on each trial, with 2 s of either rhythmic or arrhythmic 10 Hz tactile stimuli. Their task was to detect a subsequent tactile target either in-phase or out-of-phase with the rhythmic entrainment. Contrary to our hypothesis, we observed no evidence for sensory entrainment in response times, sensitivity or response bias. In line with several other recently reported null findings, our data suggest that behaviorally relevant sensory phase-entrainment might require very specific stimulus parameters, and may not generalize to the tactile domain.
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Nobre AC, van Ede F. Attention in flux. Neuron 2023; 111:971-986. [PMID: 37023719 DOI: 10.1016/j.neuron.2023.02.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 02/20/2023] [Accepted: 02/22/2023] [Indexed: 04/08/2023]
Abstract
Selective attention comprises essential infrastructural functions supporting cognition-anticipating, prioritizing, selecting, routing, integrating, and preparing signals to guide adaptive behavior. Most studies have examined its consequences, systems, and mechanisms in a static way, but attention is at the confluence of multiple sources of flux. The world advances, we operate within it, our minds change, and all resulting signals progress through multiple pathways within the dynamic networks of our brains. Our aim in this review is to raise awareness of and interest in three important facets of how timing impacts our understanding of attention. These include the challenges posed to attention by the timing of neural processing and psychological functions, the opportunities conferred to attention by various temporal structures in the environment, and how tracking the time courses of neural and behavioral modulations with continuous measures yields surprising insights into the workings and principles of attention.
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Affiliation(s)
- Anna C Nobre
- Department of Experimental Psychology, University of Oxford, Oxford OX2 6GG, UK; Oxford Centre for Human Brain Activity, Wellcome Centre for Integrative Neuroimaging, Department of Psychiatry, University of Oxford, Oxford OX3 7JX, UK.
| | - Freek van Ede
- Institute for Brain and Behavior Amsterdam, Department of Experimental and Applied Psychology, Vrije Universiteit Amsterdam, Amsterdam 1081BT, the Netherlands.
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Cansler HL, in ’t Zandt EE, Carlson KS, Khan WT, Ma M, Wesson DW. Organization and engagement of a prefrontal-olfactory network during olfactory selective attention. Cereb Cortex 2023; 33:1504-1526. [PMID: 35511680 PMCID: PMC9930634 DOI: 10.1093/cercor/bhac153] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 03/18/2022] [Accepted: 03/19/2022] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Sensory perception is profoundly shaped by attention. Attending to an odor strongly regulates if and how it is perceived - yet the brain systems involved in this process are unknown. Here we report integration of the medial prefrontal cortex (mPFC), a collection of brain regions integral to attention, with the olfactory system in the context of selective attention to odors. METHODS First, we used tracing methods to establish the tubular striatum (TuS, also known as the olfactory tubercle) as the primary olfactory region to receive direct mPFC input in rats. Next, we recorded (i) local field potentials from the olfactory bulb (OB), mPFC, and TuS, or (ii) sniffing, while rats completed an olfactory selective attention task. RESULTS Gamma power and coupling of gamma oscillations with theta phase were consistently high as rats flexibly switched their attention to odors. Beta and theta synchrony between mPFC and olfactory regions were elevated as rats switched their attention to odors. Finally, we found that sniffing was consistent despite shifting attentional demands, suggesting that the mPFC-OB theta coherence is independent of changes in active sampling. CONCLUSIONS Together, these findings begin to define an olfactory attention network wherein mPFC activity, as well as that within olfactory regions, are coordinated based upon attentional states.
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Affiliation(s)
- Hillary L Cansler
- Department of Pharmacology and Therapeutics, Center for Smell and Taste, Center for Addiction Research and Education, Norman Fixel Institute for Neurological Diseases, University of Florida, 1200 Newell Dr., Gainesville, FL 32610, United States
| | - Estelle E in ’t Zandt
- Department of Pharmacology and Therapeutics, Center for Smell and Taste, Center for Addiction Research and Education, Norman Fixel Institute for Neurological Diseases, University of Florida, 1200 Newell Dr., Gainesville, FL 32610, United States
| | - Kaitlin S Carlson
- Department of Pharmacology and Therapeutics, Center for Smell and Taste, Center for Addiction Research and Education, Norman Fixel Institute for Neurological Diseases, University of Florida, 1200 Newell Dr., Gainesville, FL 32610, United States
| | - Waseh T Khan
- Department of Pharmacology and Therapeutics, Center for Smell and Taste, Center for Addiction Research and Education, Norman Fixel Institute for Neurological Diseases, University of Florida, 1200 Newell Dr., Gainesville, FL 32610, United States
| | - Minghong Ma
- Department of Neuroscience, University of Pennsylvania Perelman School of Medicine, 110 Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104, United States
| | - Daniel W Wesson
- Department of Pharmacology and Therapeutics, Center for Smell and Taste, Center for Addiction Research and Education, Norman Fixel Institute for Neurological Diseases, University of Florida, 1200 Newell Dr., Gainesville, FL 32610, United States
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Snapiri L, Kaplan Y, Shalev N, Landau AN. Rhythmic modulation of visual discrimination is linked to individuals' spontaneous motor tempo. Eur J Neurosci 2023; 57:646-656. [PMID: 36512369 DOI: 10.1111/ejn.15898] [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: 08/18/2022] [Revised: 11/17/2022] [Accepted: 12/01/2022] [Indexed: 12/15/2022]
Abstract
The impact of external rhythmic structure on perception has been demonstrated across different modalities and experimental paradigms. However, recent findings emphasize substantial individual differences in rhythm-based perceptual modulation. Here, we examine the link between spontaneous rhythmic preferences, as measured through the motor system, and individual differences in rhythmic modulation of visual discrimination. As a first step, we measure individual rhythmic preferences using the spontaneous tapping task. Then we assess perceptual rhythmic modulation using a visual discrimination task in which targets can appear either in-phase or out-of-phase with a preceding rhythmic stream of visual stimuli. The tempo of the preceding stream was manipulated over different experimental blocks (0.77 Hz, 1.4 Hz, 2 Hz). We find that visual rhythmic stimulation modulates discrimination performance. The modulation is dependent on the tempo of stimulation, with maximal perceptual benefits for the slowest tempo of stimulation (0.77 Hz). Most importantly, the strength of modulation is also linked to individuals' spontaneous motor tempo. Individuals with slower spontaneous tempi show greater rhythmic modulation compared to individuals with faster spontaneous tempi. This finding suggests that different tempi affect the cognitive system with varying levels of efficiency and that self-generated rhythms impact our ability to utilize rhythmic structure in the environment for guiding perception and performance.
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Affiliation(s)
- Leah Snapiri
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Yael Kaplan
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Nir Shalev
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Ayelet N Landau
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel.,Department of Cognitive Science, The Hebrew University of Jerusalem, Jerusalem, Israel
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Herrmann B, Maess B, Johnsrude IS. Sustained responses and neural synchronization to amplitude and frequency modulation in sound change with age. Hear Res 2023; 428:108677. [PMID: 36580732 DOI: 10.1016/j.heares.2022.108677] [Citation(s) in RCA: 1] [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] [Received: 04/28/2022] [Revised: 12/09/2022] [Accepted: 12/16/2022] [Indexed: 12/23/2022]
Abstract
Perception of speech requires sensitivity to features, such as amplitude and frequency modulations, that are often temporally regular. Previous work suggests age-related changes in neural responses to temporally regular features, but little work has focused on age differences for different types of modulations. We recorded magnetoencephalography in younger (21-33 years) and older adults (53-73 years) to investigate age differences in neural responses to slow (2-6 Hz sinusoidal and non-sinusoidal) modulations in amplitude, frequency, or combined amplitude and frequency. Audiometric pure-tone average thresholds were elevated in older compared to younger adults, indicating subclinical hearing impairment in the recruited older-adult sample. Neural responses to sound onset (independent of temporal modulations) were increased in magnitude in older compared to younger adults, suggesting hyperresponsivity and a loss of inhibition in the aged auditory system. Analyses of neural activity to modulations revealed greater neural synchronization with amplitude, frequency, and combined amplitude-frequency modulations for older compared to younger adults. This potentiated response generalized across different degrees of temporal regularity (sinusoidal and non-sinusoidal), although neural synchronization was generally lower for non-sinusoidal modulation. Despite greater synchronization, sustained neural activity was reduced in older compared to younger adults for sounds modulated both sinusoidally and non-sinusoidally in frequency. Our results suggest age differences in the sensitivity of the auditory system to features present in speech and other natural sounds.
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Affiliation(s)
- Björn Herrmann
- Rotman Research Institute, Baycrest, North York, ON M6A 2E1, Canada; Department of Psychology, University of Toronto, Toronto, ON M5S 1A1, Canada; Department of Psychology & Brain and Mind Institute, The University of Western Ontario, London, ON N6A 3K7, Canada.
| | - Burkhard Maess
- Max Planck Institute for Human Cognitive and Brain Sciences, Brain Networks Unit, Leipzig 04103, Germany
| | - Ingrid S Johnsrude
- Department of Psychology & Brain and Mind Institute, The University of Western Ontario, London, ON N6A 3K7, Canada; School of Communication Sciences & Disorders, The University of Western Ontario, London, ON N6A 5B7, Canada
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Cross-modal attentional effects of rhythmic sensory stimulation. Atten Percept Psychophys 2022; 85:863-878. [PMID: 36385670 PMCID: PMC10066103 DOI: 10.3758/s13414-022-02611-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/31/2022] [Indexed: 11/18/2022]
Abstract
AbstractTemporal regularities are ubiquitous in our environment. The theory of entrainment posits that the brain can utilize these regularities by synchronizing neural activity with external events, thereby, aligning moments of high neural excitability with expected upcoming stimuli and facilitating perception. Despite numerous accounts reporting entrainment of behavioural and electrophysiological measures, evidence regarding this phenomenon remains mixed, with several recent studies having failed to provide confirmatory evidence. Notably, it is currently unclear whether and for how long the effects of entrainment can persist beyond their initiating stimulus, and whether they remain restricted to the stimulated sensory modality or can cross over to other modalities. Here, we set out to answer these questions by presenting participants with either visual or auditory rhythmic sensory stimulation, followed by a visual or auditory target at six possible time points, either in-phase or out-of-phase relative to the initial stimulus train. Unexpectedly, but in line with several recent studies, we observed no evidence for cyclic fluctuations in performance, despite our design being highly similar to those used in previous demonstrations of sensory entrainment. However, our data revealed a temporally less specific attentional effect, via cross-modally facilitated performance following auditory compared with visual rhythmic stimulation. In addition to a potentially higher salience of auditory rhythms, this could indicate an effect on oscillatory 3-Hz amplitude, resulting in facilitated cognitive control and attention. In summary, our study further challenges the generality of periodic behavioural modulation associated with sensory entrainment, while demonstrating a modality-independent attention effect following auditory rhythmic stimulation.
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Kawashima T, Shibusawa S, Amano K. Frequency- and Phase-Dependent Effects of Auditory Entrainment on Attentional Blink. Eur J Neurosci 2022; 56:4411-4424. [PMID: 35796700 DOI: 10.1111/ejn.15760] [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: 10/26/2021] [Revised: 05/26/2022] [Accepted: 06/09/2022] [Indexed: 11/30/2022]
Abstract
Attentional blink (AB) is the impaired detection of a second target (T2) after a first target has been identified. In this paper, we investigated the functional roles of alpha and theta oscillations on AB by determining how much preceding rhythmic auditory stimulation affected the performance of AB. Healthy young adults participated in the experiment online. We found that when two targets were embedded in rapid serial visual presentation (RSVP) of distractors at 10 Hz (i.e., alpha frequency), the magnitude of AB increased with auditory stimuli. The increase was limited to the case when the frequency and phase of auditory stimuli matched the following RSVP stream. On the contrary, when only two targets were presented without a distractor, auditory stimuli at theta, not alpha, increased the AB magnitude. These results indicate that neural oscillations at two different frequencies, namely, alpha and theta, are involved in attentional blink.
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Affiliation(s)
- Tomoya Kawashima
- Graduate School of Human Sciences, Osaka University.,Center for Information and Neural Networks (CiNet), Advanced ICT Research Institute, National Institute of Information and Communications Technology (NICT) and Osaka University
| | - Shuka Shibusawa
- Center for Information and Neural Networks (CiNet), Advanced ICT Research Institute, National Institute of Information and Communications Technology (NICT) and Osaka University.,Japan Society for the Promotion of Science
| | - Kaoru Amano
- Center for Information and Neural Networks (CiNet), Advanced ICT Research Institute, National Institute of Information and Communications Technology (NICT) and Osaka University.,Graduate School of Information Science and Technology, The University of Tokyo
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