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Rout TW, Duda AT, De Blasio FM, Clarke AR, Barry RJ. Global alpha power fluctuations in a self-caught mind-wandering paradigm are independent of arousal. Int J Psychophysiol 2024; 205:112428. [PMID: 39233206 DOI: 10.1016/j.ijpsycho.2024.112428] [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: 06/06/2024] [Revised: 08/30/2024] [Accepted: 09/01/2024] [Indexed: 09/06/2024]
Abstract
Mind-wandering is characterised as the emergence of thought and emotions which shift attention away from a primary task. It is thought to consume up to 50 % of our waking lives and has several negative implications. Breath-counting is one task that has been utilised in conjunction with electroencephalography (EEG) to examine the brain states associated with mind-wandering. Research has consistently found reductions in alpha oscillations during periods of mind-wandering relative to breath-focus. It is possible that such fluctuations reflect an arousal mechanism warranting further investigation. Thirty-seven participants completed a 15 min breath-counting task, with simultaneous recording of EEG and skin conductance level (SCL). During this task participants were required to self-identify periods of mind-wandering via button-press. Event-related spectral perturbation (ERSP) analysis was used to quantify changes in global alpha power (8-13 Hz) relative to the button press. The -8 to -4 s period prior to button-press was assessed as mind-wandering, and the 4 to 8 s period following the button-press as breath-focus. Relative to breath-focus, mind-wandering was associated with a significant decrease in global alpha power and significant increase in SCL, consistent with perceptual decoupling theory. However, changes in global alpha power and SCL did not correlate. These results suggest arousal is not the primary mechanism underlying alpha changes observed during breath-counting, thus additional processes should be considered.
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Affiliation(s)
- Thomas W Rout
- Brain & Behaviour Research Institute and School of Psychology, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522, Australia
| | - Alexander T Duda
- Brain & Behaviour Research Institute and School of Psychology, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522, Australia.
| | - Frances M De Blasio
- Brain & Behaviour Research Institute and School of Psychology, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522, Australia
| | - Adam R Clarke
- Brain & Behaviour Research Institute and School of Psychology, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522, Australia
| | - Robert J Barry
- Brain & Behaviour Research Institute and School of Psychology, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522, Australia
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Soltanzadeh S, Chitsaz S, Kazemi R. Color and brightness at work: Shedding some light on mind wandering. Brain Behav 2024; 14:e70020. [PMID: 39295080 PMCID: PMC11410860 DOI: 10.1002/brb3.70020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Revised: 08/02/2024] [Accepted: 08/07/2024] [Indexed: 09/21/2024] Open
Abstract
INTRODUCTION Occupational hazards are partly caused by the physical factors of the work environment, among which are ambient color and brightness, which can interfere with cognitive performance. Especially in modern work environments, performance relies heavily on cognitive functions such as attention, and an important factor in disrupting sustained attention is mind wandering (MW). This study aimed to investigate the effects of white and blue colors with two brightness levels on sustained attention and brain electrophysiology. METHODS A total of 20 participants were exposed to 4 different conditions (white and blue as color and 300 and 800 lx as the brightness level) in separate blocks in a virtual reality environment in which a continuous performance test (CPT) was performed. RESULTS The high brightness blue condition induced significant changes in sustained attention. MW network analysis showed a significant decrease in delta frequency band in the blue color condition with high brightness and beta decrease in the blue color condition with low brightness, whereas the activity of MW network increased when exposed to the white color condition. CONCLUSION High-brightness blue light resulted in better sustained attention and decreased activity of MW-related neural regions. It is thus recommended that these results be taken into consideration in the interior design of educational settings and cars among other environments that require a high level and maintenance of cognitive functions, especially sustained attention.
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Affiliation(s)
- Soodabeh Soltanzadeh
- Department of Design and CreativityInstitute for Cognitive Science StudiesTehranIran
| | - Shaghayegh Chitsaz
- Department of Design and CreativityInstitute for Cognitive Science StudiesTehranIran
| | - Reza Kazemi
- Faculty of EntrepreneurshipUniversity of TehranTehranIran
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Sihn D, Kim J, Kim SP. Meditation-type specific reduction in infra-slow activity of electroencephalogram. Biomed Eng Lett 2024; 14:823-831. [PMID: 38946818 PMCID: PMC11208365 DOI: 10.1007/s13534-024-00377-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 03/24/2024] [Accepted: 03/31/2024] [Indexed: 07/02/2024] Open
Abstract
Purpose Meditation is renowned for its positive effects on cognitive abilities and stress reduction. It has been reported that the amplitude of electroencephalographic (EEG) infra-slow activity (ISA, < 0.1 Hz) is reduced as the stress level decreases. Consequently, we aimed to determine if EEG ISA amplitude decreases as a result of meditation practice across various traditions. Methods To this end, we analyzed an open dataset comprising EEG data acquired during meditation sessions from experienced practitioners in the Vipassana tradition-which integrates elements of focused attention and open monitoring, akin to mindfulness meditation-and in the Himalayan Yoga and Isha Shoonya traditions, which emphasize focused attention and open monitoring, respectively. Results A general trend was observed where EEG ISA amplitude tended to decrease in experienced meditators from these traditions compared to novices, particularly significant in the 0.03-0.08 Hz band for Vipassana meditators. Therefore, our analysis focused on this ISA frequency band. Specifically, a notable decrease in EEG ISA amplitude was observed in Vipassana meditators, predominantly in the left-frontal region. This reduction in EEG ISA amplitude was also accompanied by a decrease in phase-amplitude coupling (PAC) between the ISA phase and alpha band (8-12 Hz) amplitude, which implied decreased neural excitability fluctuations. Conclusion Our findings suggest that not only does EEG ISA amplitude decrease in experienced meditators from traditions that incorporate both focused attention and open monitoring, but this decrease may also signify a diminished influence of neural excitability fluctuations attributed to ISA.
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Affiliation(s)
- Duho Sihn
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan, 44919 Republic of Korea
| | - Junsuk Kim
- School of Information Convergence, Kwangwoon University, Seoul, 01897 Republic of Korea
| | - Sung-Phil Kim
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan, 44919 Republic of Korea
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Long Z, Fu Q, Fu X. How mind wandering influences motor control: The modulating role of movement difficulty. Neuroimage 2024; 294:120638. [PMID: 38719153 DOI: 10.1016/j.neuroimage.2024.120638] [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: 01/01/2024] [Revised: 05/01/2024] [Accepted: 05/04/2024] [Indexed: 05/12/2024] Open
Abstract
It has been found that mind wandering can impair motor control. However, it remains unclear whether the impact of mind wandering on motor control is modulated by movement difficulty and its associated neural mechanisms. To address this issue, we manipulated movement difficulty using handedness and finger dexterity separately in two signal-response tasks with identical experiment designs, in which right-handed participants performed key-pressing and key-releasing movements with the specified fingers, and they had to intermittently report whether their attention was "On task" or "Off task." Key-releasing with the right index finger (RI) had a faster reaction time and stronger contralateral delta-theta (1-7 Hz) functional connectivity than with the left index (LI) in Experiment 1, and mind wandering only reduced the contralateral delta-theta functional connectivity and midfrontal delta-theta activity for key-releasing with RI. Key-pressing with right index and middle fingers (RIR) had a faster reaction time and stronger midfrontal delta-theta activity than with right index and ring fingers (RIR) in Experiment 2, and mind wandering only reduced the midfrontal delta-theta activity for key-pressing with RIM. Theta oscillations are vital in motor control. These findings suggest that mind wandering only impairs the motor control of relatively simple movements without affecting the difficult ones. It supports the notion that mind wandering competes for executive resources with the primary task. Moreover, the quantity of executive resources recruited for a task and how these resources are allocated is contingent upon the task difficulty, which may determine whether mind wandering would interfere with motor control.
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Affiliation(s)
- Zhengkun Long
- State Key Laboratory of Brain and Cognitive Science, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China; Department of Psychology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qiufang Fu
- State Key Laboratory of Brain and Cognitive Science, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China; Department of Psychology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaolan Fu
- State Key Laboratory of Brain and Cognitive Science, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China; Department of Psychology, University of Chinese Academy of Sciences, Beijing 100049, China.
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Alaerts K, Moerkerke M, Daniels N, Zhang Q, Grazia R, Steyaert J, Prinsen J, Boets B. Chronic oxytocin improves neural decoupling at rest in children with autism: an exploratory RCT. J Child Psychol Psychiatry 2024. [PMID: 38400592 DOI: 10.1111/jcpp.13966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/17/2024] [Indexed: 02/25/2024]
Abstract
BACKGROUND Shifts in peak frequencies of oscillatory neural rhythms are put forward as a principal mechanism by which cross-frequency coupling/decoupling is implemented in the brain. During active neural processing, functional integration is facilitated through transitory formations of "harmonic" cross-frequency couplings, whereas "nonharmonic" decoupling among neural oscillatory rhythms is postulated to characterize the resting, default state of the brain, minimizing the occurrence of spurious, noisy, background couplings. METHODS Within this exploratory, randomized, placebo-controlled trial, we assessed whether the transient occurrence of nonharmonic and harmonic relationships between peak-frequencies in the alpha (8-14 Hz) and theta (4-8 Hz) bands is impacted by intranasal administration of oxytocin, a neuromodulator implicated in improving homeostasis and reducing stress/anxiety. To do so, resting-state electroencephalography was acquired before and after 4 weeks of oxytocin administration (12 IU twice-daily) in children with autism spectrum disorder (8-12 years, n = 33 oxytocin; n = 34 placebo). At the baseline, neural assessments of children with autism were compared with those of a matched cohort of children without autism (n = 40). RESULTS Compared to nonautistic peers, autistic children displayed a lower incidence of nonharmonic alpha-theta cross-frequency decoupling, indicating a higher incidence of spurious "noisy" coupling in their resting brain (p = .001). Dimensionally, increased neural coupling was associated with more social difficulties (p = .002) and lower activity of the parasympathetic "rest & digest" branch of the autonomic nervous system (p = .018), indexed with high-frequency heart-rate-variability. Notably, after oxytocin administration, the transient formation of nonharmonic cross-frequency configurations was increased in the cohort of autistic children (p < .001), indicating a beneficial effect of oxytocin on reducing spurious cross-frequency-interactions. Furthermore, parallel epigenetics changes of the oxytocin receptor gene indicated that the neural effects were likely mediated by changes in endogenous oxytocinergic signaling (p = .006). CONCLUSIONS Chronic oxytocin induced important homeostatic changes in the resting-state intrinsic neural frequency architecture, reflective of reduced noisy oscillatory couplings and improved signal-to-noise properties.
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Affiliation(s)
- Kaat Alaerts
- Research Group for Neurorehabilitation, Neuromodulation Laboratory, KU Leuven, Leuven, Belgium
- Leuven Autism Research (LAuRes), KU Leuven, Leuven, Belgium
| | - Matthijs Moerkerke
- Leuven Autism Research (LAuRes), KU Leuven, Leuven, Belgium
- Department of Neurosciences, Center for Developmental Psychiatry, KU Leuven, Leuven, Belgium
| | - Nicky Daniels
- Research Group for Neurorehabilitation, Neuromodulation Laboratory, KU Leuven, Leuven, Belgium
- Leuven Autism Research (LAuRes), KU Leuven, Leuven, Belgium
| | - Qianqian Zhang
- Research Group for Neurorehabilitation, Neuromodulation Laboratory, KU Leuven, Leuven, Belgium
- Leuven Autism Research (LAuRes), KU Leuven, Leuven, Belgium
| | - Ricchiuti Grazia
- Research Group for Neurorehabilitation, Neuromodulation Laboratory, KU Leuven, Leuven, Belgium
- Leuven Autism Research (LAuRes), KU Leuven, Leuven, Belgium
| | - Jean Steyaert
- Leuven Autism Research (LAuRes), KU Leuven, Leuven, Belgium
| | - Jellina Prinsen
- Research Group for Neurorehabilitation, Neuromodulation Laboratory, KU Leuven, Leuven, Belgium
- Leuven Autism Research (LAuRes), KU Leuven, Leuven, Belgium
| | - Bart Boets
- Leuven Autism Research (LAuRes), KU Leuven, Leuven, Belgium
- Department of Neurosciences, Center for Developmental Psychiatry, KU Leuven, Leuven, Belgium
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Nejati V, Zamiran B, Nitsche MA. The Interaction of the Dorsolateral and Ventromedial Prefrontal Cortex During Mind Wandering. Brain Topogr 2023:10.1007/s10548-023-00970-z. [PMID: 37202646 DOI: 10.1007/s10548-023-00970-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 05/05/2023] [Indexed: 05/20/2023]
Abstract
BACKGROUND AND AIMS Mind wandering refers to spontaneously occurring, often disruptive thoughts during an ongoing task or resting state. The ventromedial prefrontal cortex (vmPFC) and dorsolateral prefrontal cortex (dlPFC) are two main cortical areas which are involved in this process. This study aimed to explore the interaction of these areas during mind wandering by enhancing specific oscillatory activity of these areas via transcranial alternating current stimulation (tACS) in the theta frequency range. MATERIAL AND METHODS Eighteen healthy adults participated in a randomized, single-blinded, crossover study. tACS (1.5 mA, 6 Hz) was applied in five sessions with one week interval via (1) two channels with synchronized stimulation over the left dlPFC and right vmPFC, (2) the same electrode placement with anti-phase stimulation, (3) stimulation over the left dlPFC only, (4) stimulation over right vmPFC only, and (5) sham stimulation. The return electrodes were placed over the contralateral shoulder in all conditions. The sustained attention to response task (SART) with embedded probes about task-unrelated-thoughts and awareness of these thoughts was performed during intervention. RESULTS Stimulation did not alter SART performance. Right vmPFC stimulation decreased mind wandering and increased awareness of mind wandering. Left dlPFC stimulation and desynchronized stimulation over the dlPFC and vmPFC increased mind wandering compared to the sham stimulation condition. Synchronized stimulation had no effect on mind wandering, but increased awareness of mind wandering. CONCLUSION The results suggest that regional entrainment of the vmPFC decreases mind wandering and increases awareness of mind wandering, whereas regional entrainment of the dlPFC increases mind wandering, but decreases awareness. Under desynchronized stimulation of both areas, the propensity of mind wandering was increased, whereas synchronized stimulation increased the awareness of mind wandering. These results suggest a role of the dlPFC in initiation of mind wandering, whereas the vmPFC downregulates mind wandering, and might exert this function by counteracting respective dlPFC effects via theta oscillations.
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Affiliation(s)
- Vahid Nejati
- Department of Psychology, Shahid Beheshti University Tehran, Tehran, Iran.
| | - Bahar Zamiran
- Department of Psychology, Shahid Beheshti University Tehran, Tehran, Iran
| | - Michael A Nitsche
- Leibniz Research Centre for Working Environment and Human Factors, Department of Psychology and Neurosciences, Dortmund, Germany
- Department of Neurology, University Medical Hospital Bergmannsheil, Bochum, Germany
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Bao Z, Frewen P. Sense of self in mind and body: an eLORETA-EEG study. Neurosci Conscious 2022; 2022:niac017. [PMID: 36530551 PMCID: PMC9748806 DOI: 10.1093/nc/niac017] [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: 05/04/2022] [Revised: 10/06/2022] [Accepted: 11/03/2022] [Indexed: 12/23/2022] Open
Abstract
The human brain engages the sense of self through both semantic and somatic self-referential processing (SRP). Alpha and theta oscillations have been found to underlie SRP but have not been compared with respect to semantic and somatic SRP. We recorded electroencephalography (EEG) from 50 participants during focused internal attention on life roles (e.g. "friend") and outer body (e.g. "arms") compared to resting state and an external attention memory task and localized the sources of on-scalp alpha (8-12 Hz) and theta (4-8 Hz) EEG signals with exact low-resolution tomography. Logarithm of F-ratios was calculated to compare differences in alpha and theta power between SRP conditions, resting state, and external attention. Results indicated that compared to resting state, semantic SRP induced lower theta in the frontal cortex and higher theta in the parietal cortex, whereas somatic SRP induced lower alpha in the frontal and insula cortex and higher alpha in the parietal cortex. Furthermore, results indicated that compared to external attention, both semantic and somatic SRP induced higher alpha in the dorsolateral prefrontal cortex with lateralized patterns based on task condition. Finally, an analysis directly comparing semantic and somatic SRP indicated frontal-parietal and left-right lateralization of SRP in the brain. Our results suggest the alpha and theta oscillations in the frontal, parietal, and the insula cortex may play crucial roles in semantic and somatic SRP.
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Affiliation(s)
| | - Paul Frewen
- *Correspondence address. Department of Psychiatry, Schulich School of Medicine and Dentistry, 339 Windermere Rd., London, ON N6A 5A5, Canada. Tel: +519 685 8500 E-mail:
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Rodriguez-Larios J, ElShafei A, Wiehe M, Haegens S. Visual working memory recruits two functionally distinct alpha rhythms in posterior cortex. eNeuro 2022; 9:ENEURO.0159-22.2022. [PMID: 36171059 PMCID: PMC9536853 DOI: 10.1523/eneuro.0159-22.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 06/20/2022] [Accepted: 07/12/2022] [Indexed: 11/21/2022] Open
Abstract
Oscillatory activity in the human brain is dominated by posterior alpha oscillations (8-14 Hz), which have been shown to be functionally relevant in a wide variety of cognitive tasks. Although posterior alpha oscillations are commonly considered a single oscillator anchored at an individual alpha frequency (IAF; ∼10 Hz), previous work suggests that IAF reflects a spatial mixture of different brain rhythms. In this study, we assess whether Independent Component Analysis (ICA) can disentangle functionally distinct posterior alpha rhythms in the context of visual short-term memory retention. Magnetoencephalography (MEG) was recorded in 33 subjects while performing a visual working memory task. Group analysis at sensor level suggested the existence of a single posterior alpha oscillator that increases in power and decreases in frequency during memory retention. Conversely, single-subject analysis of independent components revealed the existence of two dissociable alpha rhythms: one that increases in power during memory retention (Alpha1) and another one that decreases in power (Alpha2). Alpha1 and Alpha2 rhythms were differentially modulated by the presence of visual distractors (Alpha1 increased in power while Alpha2 decreased) and had an opposite relationship with accuracy (positive for Alpha1 and negative for Alpha2). In addition, Alpha1 rhythms showed a lower peak frequency, a narrower peak width, a greater relative peak amplitude and a more central source than Alpha2 rhythms. Together, our results demonstrate that modulations in posterior alpha oscillations during short-term memory retention reflect the dynamics of at least two distinct brain rhythms with different functions and spatiospectral characteristics.Significance statementAlpha oscillations are the most prominent feature of the human brain's electrical activity, and consist of rhythmic neuronal activity in posterior parts of the cortex. Alpha is usually considered a single brain rhythm that changes in power and frequency to support cognitive operations. We here show that posterior alpha entails at least two dissociable rhythms with distinct functions and characteristics. These findings could solve previous inconsistencies in the literature regarding the direction of task-related alpha power/frequency modulations and their relation to cognitive performance. In addition, the existence of two distinct posterior alpha rhythms could have important consequences for the design of neurostimulation protocols aimed at modulating alpha oscillations and subsequently cognition.
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Affiliation(s)
- Julio Rodriguez-Larios
- Dept. of Psychiatry, Columbia University, New York, USA, NY 10032
- Div. of Systems Neuroscience, New York State Psychiatric Institute, New York, USA, NY 10032
| | - Alma ElShafei
- Donders Institute for Brain, Cognition & Behavior, Radboud University, Nijmegen, The Netherlands, 6525 EN
| | - Melanie Wiehe
- Donders Institute for Brain, Cognition & Behavior, Radboud University, Nijmegen, The Netherlands, 6525 EN
| | - Saskia Haegens
- Dept. of Psychiatry, Columbia University, New York, USA, NY 10032
- Div. of Systems Neuroscience, New York State Psychiatric Institute, New York, USA, NY 10032
- Donders Institute for Brain, Cognition & Behavior, Radboud University, Nijmegen, The Netherlands, 6525 EN
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Alaerts K, Bernaerts S, Wenderoth N. Effects of single- and multiple-dose oxytocin treatment on amygdala low-frequency BOLD fluctuations and BOLD spectral dynamics in autism. Transl Psychiatry 2022; 12:393. [PMID: 36127337 PMCID: PMC9489696 DOI: 10.1038/s41398-022-02158-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 09/02/2022] [Accepted: 09/07/2022] [Indexed: 11/17/2022] Open
Abstract
Prior neuroimaging clinical trials investigating the neural effects of intranasal administration of the neuropeptide oxytocin demonstrated a key role of the amygdala in oxytocin's neuromodulatory effects. These studies mostly demonstrated the acute effects of single-dose administrations, examining task-dependent effects of oxytocin on brain activity elicited during explicit experimental tasks or stimuli presentations. The increased consideration of oxytocin as a potential ameliorating treatment in autism spectrum disorder (ASD) requires a better understanding of how multiple-dose oxytocin administration affects intrinsic, task-free, amygdala function. In this double-blind, randomized, placebo-controlled trial with between-subject design, 38 adult men with ASD underwent resting-state fMRI scanning before and after oxytocin or placebo treatment. Effects were assessed either after a single-dose administration, consisting of 24 international units, or after multiple-dose treatment, consisting of 4 weeks of once-daily nasal spray administrations. Compared to placebo, oxytocin induced a decrease in intrinsic resting-state BOLD signal amplitudes of the bilateral amygdala (fractional amplitudes of low-frequency fluctuations) and modulated cross-frequency interactions between adjacent BOLD frequency components. The right amygdala showed a pattern of reduced cross-frequency harmonicity, while the left amygdala showed a relative increase in harmonic cross-frequency interactions after oxytocin treatment. Notably, the direction and magnitude of BOLD spectral changes induced after a single-dose were qualitatively similar to treatment effects induced after multiple-dose treatment. Furthermore, the identified spectral changes in amygdalar BOLD amplitude and cross-frequency harmonicity were associated with improved feelings of tension, reflecting oxytocin's anxiolytic, stress-reducing neuromodulatory role. The observed effects of oxytocin on amygdalar BOLD spectral characteristics and associated behaviors contribute to a deeper mechanistic understanding of the intrinsic, task-free neuromodulatory dynamics that underlie single- and multiple-dose oxytocin treatment in ASD. European Clinical Trial Registry (Eudract 2014-000586-45).
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Affiliation(s)
- Kaat Alaerts
- Department of Rehabilitation Sciences, Group Biomedical Sciences, Neuromodulation Laboratory, Neurorehabilitation Research Group, University of Leuven, KU Leuven, Leuven, Belgium.
| | - Sylvie Bernaerts
- grid.5596.f0000 0001 0668 7884Department of Rehabilitation Sciences, Group Biomedical Sciences, Neuromodulation Laboratory, Neurorehabilitation Research Group, University of Leuven, KU Leuven, Leuven, Belgium
| | - Nicole Wenderoth
- grid.5801.c0000 0001 2156 2780Department of Health Sciences and Technology, Neural Control of Movement Lab, ETH Zurich, Zurich, Switzerland
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10
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Kam JWY, Rahnuma T, Park YE, Hart CM. Electrophysiological markers of mind wandering: A systematic review. Neuroimage 2022; 258:119372. [PMID: 35700946 DOI: 10.1016/j.neuroimage.2022.119372] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Revised: 06/08/2022] [Accepted: 06/10/2022] [Indexed: 10/18/2022] Open
Abstract
The ability to mentally wander away from the external environment is a remarkable feature of the human mind. Although recent years have witnessed a surge of interest in examining mind wandering using EEG, there is no comprehensive review that summarizes and accounts for the variable findings. Accordingly, we conducted a systematic review that synthesizes evidence from EEG studies that examined the electrophysiological measures of mind wandering. Our search yielded 42 studies that met eligibility criteria. The reviewed literature converges on a reduction in the amplitude of canonical ERP components (i.e., P1, N1 and P3) as the most reliable markers of mind wandering. Spectral findings were less robust, but point towards greater activity in lower frequency bands, (i.e., delta, theta, and alpha), as well as a decrease in beta band activity, during mind wandering compared to on-task states. The variability in these findings appears to be modulated by the task context. To integrate these findings, we propose an electrophysiological account of mind wandering that explains how the brain supports this inner experience. Conclusions drawn from this work will inform future endeavours in basic science to map out electrophysiological patterns underlying mind wandering and in translational science using EEG to predict the occurrence of this phenomenon.
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Affiliation(s)
- J W Y Kam
- Department of Psychology, University of Calgary. 2500 University Dr. NW., Calgary, AB, T2N 1N4, Canada; Hotchkiss Brain Institute, University of Calgary. 3330 Hospital Dr. NW., Calgary, AB, T2N 4N1, Canada.
| | - T Rahnuma
- Hotchkiss Brain Institute, University of Calgary. 3330 Hospital Dr. NW., Calgary, AB, T2N 4N1, Canada
| | - Y E Park
- Department of Psychology, University of Calgary. 2500 University Dr. NW., Calgary, AB, T2N 1N4, Canada
| | - C M Hart
- Department of Psychology, University of Calgary. 2500 University Dr. NW., Calgary, AB, T2N 1N4, Canada
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11
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Paoletti P, Leshem R, Pellegrino M, Ben-Soussan TD. Tackling the Electro-Topography of the Selves Through the Sphere Model of Consciousness. Front Psychol 2022; 13:836290. [PMID: 35664179 PMCID: PMC9161303 DOI: 10.3389/fpsyg.2022.836290] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 03/11/2022] [Indexed: 11/13/2022] Open
Abstract
In the current hypothesis paper, we propose a novel examination of consciousness and self-awareness through the neuro-phenomenological theoretical model known as the Sphere Model of Consciousness (SMC). Our aim is to create a practical instrument to address several methodological issues in consciousness research. We present a preliminary attempt to validate the SMC via a simplified electrophysiological topographic map of the Self. This map depicts the gradual shift from faster to slower frequency bands that appears to mirror the dynamic between the various SMC states of Self. In order to explore our hypothesis that the SMC's different states of Self correspond to specific frequency bands, we present a mini-review of studies examining the electrophysiological activity that occurs within the different states of Self and in the context of specific meditation types. The theoretical argument presented here is that the SMC's hierarchical organization of three states of the Self mirrors the hierarchical organization of Focused Attention, Open Monitoring, and Non-Dual meditation types. This is followed by testable predictions and potential applications of the SMC and the hypotheses derived from it. To our knowledge, this is the first integrated electrophysiological account that combines types of Self and meditation practices. We suggest this electro-topographic framework of the Selves enables easier, clearer conceptualization of the connections between meditation types as well as increased understanding of wakefulness states and altered states of consciousness.
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Affiliation(s)
- Patrizio Paoletti
- Research Institute for Neuroscience, Education and Didactics, Patrizio Paoletti Foundation, Assisi, Italy
| | - Rotem Leshem
- Department of Criminology, Bar-Ilan University, Ramat Gan, Israel
| | - Michele Pellegrino
- Research Institute for Neuroscience, Education and Didactics, Patrizio Paoletti Foundation, Assisi, Italy
| | - Tal Dotan Ben-Soussan
- Research Institute for Neuroscience, Education and Didactics, Patrizio Paoletti Foundation, Assisi, Italy
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Lu Y, Rodriguez-Larios J. Nonlinear EEG signatures of mind wandering during breath focus meditation. CURRENT RESEARCH IN NEUROBIOLOGY 2022; 3:100056. [DOI: 10.1016/j.crneur.2022.100056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 08/31/2022] [Accepted: 09/07/2022] [Indexed: 11/17/2022] Open
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Alaerts K, Taillieu A, Prinsen J, Daniels N. Tracking transient changes in the intrinsic neural frequency architecture: Oxytocin facilitates non-harmonic relationships between alpha and theta rhythms in the resting brain. Psychoneuroendocrinology 2021; 133:105397. [PMID: 34481326 DOI: 10.1016/j.psyneuen.2021.105397] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 08/20/2021] [Accepted: 08/21/2021] [Indexed: 11/29/2022]
Abstract
Shifts in the peak frequencies of oscillatory neural rhythms have been put forward as a principal mechanism by which cross-frequency coupling and decoupling is implemented in the brain. This notion is based on the mathematical reality that neural oscillations can only fully synchronize when their peak frequencies form harmonic 2:1 relationships (e.g., f2=f1/2). Non-harmonic cross-frequency relationships, on the other hand (based on the irrational golden mean 1.618.:1), provide the highest physiologically possible desynchronized state (reducing the occurrence of spurious, noisy, background coupling), and are therefore anticipated to characterize the resting state of the brain, in which no selective information processing takes place. The present study sought to assess whether the transient occurrence of 1.6:1 non-harmonic and 2:1 harmonic relationships between peak frequencies in the alpha (8-14 Hz) and theta (4-8 Hz) bands - respectively facilitating states of decoupling or coupling between oscillatory rhythms - are impacted by the intranasal administration of a single-dose of oxytocin (OT) or placebo. To do so, continuous resting-state electroencephalography (5 min eyes open, 19 electrodes) was obtained from 96 healthy adult men before and after nasal spray administration. The transient formation of non-harmonic cross-frequency configurations between alpha and theta peak frequencies was significantly increased after OT nasal spray administration, indicating an effect of OT on reducing the intrinsic occurrence of spurious (noisy) background phase synchronizations during resting-state. As a group, the OT group also showed a significant parallel increase in high-frequency and decrease in low-frequency heart rate variability, confirming a homeostatic role of OT in balancing parasympathetic drive. Overall, non-harmonic cross-frequency configurations have been put forward to lay the ground for a healthy neural network allowing the opportunity for an efficient transition from resting state to activity. The observed effects of OT on cross-frequency dynamics are therefore interpreted to reflect a homeostatic role of OT in increasing the signal-to-noise properties of the intrinsic EEG neural frequency architecture, i.e., by precluding the occurrence of 'noisy', unwanted, spurious couplings among neural rhythms in the resting brain.
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Affiliation(s)
- Kaat Alaerts
- KU Leuven, Department of Rehabilitation Sciences, Research Group for Neurorehabilitation, Tervuursevest 101 box 1501, 3001 Leuven, Belgium.
| | - Aymara Taillieu
- KU Leuven, Department of Rehabilitation Sciences, Research Group for Neurorehabilitation, Tervuursevest 101 box 1501, 3001 Leuven, Belgium
| | - Jellina Prinsen
- KU Leuven, Department of Rehabilitation Sciences, Research Group for Neurorehabilitation, Tervuursevest 101 box 1501, 3001 Leuven, Belgium
| | - Nicky Daniels
- KU Leuven, Department of Rehabilitation Sciences, Research Group for Neurorehabilitation, Tervuursevest 101 box 1501, 3001 Leuven, Belgium
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