Predicting mind wandering episodes quarter hours in advances from EEG

Mind wandering occurs when spontaneous thought generation is increased while cognitive control is decreased, presumably in response to antagonistic effects of default mode- (DMN) and goal-directed network (GDN) activity. Previous studies assumed that DMN or GDN activity manifests in behavior with minimal delays and has rigid effects, i.e., DMN always facilitates generation of spontaneous thought and inhibits cognitive control. With those static response functions, the antagonism of DMN and GDN could explain the alternation of task focused and mind wandering states. But it rules out others, such as multi-tasking, where spontaneous thought and cognitive control are both increased, or rumination, where both are decreased. However, shifts from task focused to mind wandering have been shown to occur via a multi-tasking state. We therefore propose dynamic response functions, allowing delay or reversal of DMN and GDN effects. Dynamic response functions enabled us to stochastically predict mind wandering up to at least 30 min in advance from EEG measures of DMN and GDN activity in a tone counting task. Experimental results show both considerable delays and switches between task-positive and negative effects. Mind wandering was initiated by a barrage of DMN activity more than 20 minutes prior a report of mind wandering, directing the mental focus inward. Critically, facilitation of spontaneous thoughts occurred several minutes prior to the report. These thoughts sustained up to 10 min, after which a rebound to task-focused behavior was effectuated, notably without intervention from the GDN. Repeated GDN interventions, however, secured a basic level of task performance.

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CO2-Induced Changes in Wheat Grain Composition: Meta-Analysis and Response Functions

Agronomy ◽

10.3390/agronomy7020032 ◽

2017 ◽

Vol 7 (2) ◽

pp. 32 ◽

Cited By ~ 37

Author(s):

Malin Broberg ◽

Petra Högy ◽

Håkan Pleijel

Keyword(s):

Grain Yield ◽

Meta Analysis ◽

N Uptake ◽

Co2 Concentration ◽

Gradual Change ◽

Response Functions ◽

Wheat Grain ◽

Negative Effects ◽

Mineral Concentration ◽

Protein Nitrogen

Elevated carbon dioxide (eCO2) stimulates wheat grain yield, but simultaneously reduces protein/nitrogen (N) concentration. Also, other essential nutrients are subject to change. This study is a synthesis of wheat experiments with eCO2, estimating the effects on N, minerals (B, Ca, Cd, Fe, K, Mg, Mn, Na, P, S, Zn), and starch. The analysis was performed by (i) deriving response functions to assess the gradual change in element concentration with increasing CO2 concentration, (ii) meta-analysis to test the average magnitude and significance of observed effects, and (iii) relating CO2 effects on minerals to effects on N and grain yield. Responses ranged from zero to strong negative effects of eCO2 on mineral concentration, with the largest reductions for the nutritionally important elements of N, Fe, S, Zn, and Mg. Together with the positive but small and non-significant effect on starch concentration, the large variation in effects suggests that CO2-induced responses cannot be explained only by a simple dilution model. To explain the observed pattern, uptake and transport mechanisms may have to be considered, along with the link of different elements to N uptake. Our study shows that eCO2 has a significant effect on wheat grain stoichiometry, with implications for human nutrition in a world of rising CO2.

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Local Environmental Effects in Magnetic Alloys and Multilayers: Calculations of the Static Response Functions

MRS Proceedings ◽

10.1557/proc-166-121 ◽

1989 ◽

Vol 166 ◽

Author(s):

D. D. Johnson ◽

J. B. Staunton ◽

B. L. Györffy ◽

F. J. Pinski ◽

G. M. Stocks

Keyword(s):

Diffuse Scattering ◽

Mean Field ◽

Chemical Environment ◽

Response Functions ◽

Static Response ◽

Magnetic Alloys ◽

Multilayer Systems ◽

Local Moments ◽

Statistical Mechanical ◽

Bulk Alloys

ABSTRACTWe have developed an ab-initio method for calculating the static response functions in substitutional alloys. For magnetic alloys, in addition to the nuclear diffuse scattering, a contribution to the alloy diffuse scattering intensities results from the response of the local moments to changes in the ‘local’ chemical environment (i.e. ∂μi/∂cj). We present results of firstprinciples calculations of these ‘local’ response functions in magnetic alloys. These response functions, which may be directly compared to neutron-scattering and Mößbauer experiments, are derived via a mean-field statistical mechanical description of compositional fluctuations in alloys. The statistical averages are performed via the Korringa-Kohn-Rostoker coherent potential approximation, which incorporates the electronic structure of the high-temperature, chemically disordered state. As a first application of the theory, we have investigated the environmental dependence of the moments in NiFe alloys and FeV alloys and multilayers. We compare our results with experiments on bulk alloys and multilayers. Also, a comparison is made to a set of first-principle ‘supercell’ calculations. Although preliminary, the results demonstrate the utility of these response functions for investigating the effects of changes in the chemical environment on the alloy moments and for aiding experimental interpretation in other multilayer systems that are less experimentally amenable than FeV.

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Catching the wandering mind: Meditation as a window into spontaneous thought

10.31231/osf.io/kjyr8 ◽

2017 ◽

Author(s):

Wendy Hasenkamp

Keyword(s):

Mind Wandering ◽

Neural Correlates ◽

Physiological Measures ◽

Great Utility ◽

Spontaneous Thought ◽

New Research ◽

The Mind ◽

Subjective Reports ◽

Insight Into ◽

Research Recommendations

This chapter considers a form of attention-based meditation as a novel means to gain insight into the mechanisms and phenomenology of spontaneous thought. Focused attention (FA) meditation involves keeping one’s attention on a chosen object, and repeatedly catching the mind when it strays from the object into spontaneous thought. This practice can thus be viewed as a kind of self-caught mind wandering paradigm, which suggests it may have great utility for research on spontaneous thought. Current findings about the effects of meditation on mind wandering and meta-awareness are reviewed, and implications for new research paradigms that leverage first-person reporting during FA meditation are discussed. Specifically, research recommendations are made that may enable customized analysis of individual episodes of mind wandering and their neural correlates. It is hoped that by combining detailed subjective reports from experienced meditators with rigorous objective physiological measures, we can advance our understanding of human consciousness.

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How Does the Waking and Sleeping Brain Produce Spontaneous Thought and Imagery, and Why?

10.1093/oxfordhb/9780190464745.013.36 ◽

2018 ◽

Author(s):

John S. Antrobus

Keyword(s):

Cognitive Processes ◽

Mind Wandering ◽

Future Research ◽

Neural Processes ◽

Hard Evidence ◽

Future Value ◽

Spontaneous Imagery ◽

Spontaneous Thought

Although mind-wandering and dreaming often appear as trivial or distracting cognitive processes, this chapter suggests that they may also contribute to the evaluation, sorting, and saving of representations of recent events of future value to an individual. But 50 years after spontaneous imagery—night dreaming—was first compared to concurrent cortical EEG, there is limited hard evidence on the neural processes that produce either visual dreaming imagery or the speech imagery of waking spontaneous thought. The authors propose here an outline of a neurocognitive model of such processes with suggestions for future research that may contribute to a better understanding of their utility.

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Three-Dimensional Thermo-Elasto-Hydrodynamic Computational Fluid Dynamics Model of a Tilting Pad Journal Bearing—Part II: Dynamic Response

Journal of Tribology ◽

10.1115/1.4043350 ◽

2019 ◽

Vol 141 (6) ◽

Cited By ~ 6

Author(s):

Jongin Yang ◽

Alan Palazzolo

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Dynamic Response ◽

Journal Bearing ◽

Three Dimensional ◽

Static Response ◽

Damping Coefficients ◽

Tilting Pad ◽

Stiffness And Damping ◽

Tilting Pad Journal Bearing

Part II presents a novel approach for predicting dynamic coefficients for a tilting pad journal bearing (TPJB) using computational fluid dynamics (CFD) and finite element method (FEM), including fully coupled elastic deflection, heat transfer, and fluid dynamics. Part I presented a similarly novel, high fidelity approach for TPJB static response prediction which is a prerequisite for the dynamic characteristic determination. The static response establishes the equilibrium operating point values for eccentricity, attitude angle, deflections, temperatures, pressures, etc. The stiffness and damping coefficients are obtained by perturbing the pad and journal motions about this operating point to determine changes in forces and moments. The stiffness and damping coefficients are presented in “synchronously reduced form” as required by American Petroleum Institute (API) vibration standards. Similar to Part I, an advanced three-dimensional thermal—Reynolds equation code validates the CFD code for the special case when flow Between Pad (BP) regions is ignored, and the CFD and Reynolds pad boundary conditions are made identical. The results show excellent agreement for this validation case. Similar to the static response case, the dynamic characteristics from the Reynolds model show large discrepancies compared with the CFD results, depending on the Reynolds mixing coefficient (MC). The discrepancies are a concern given the key role that stiffness and damping coefficients serve instability and response predictions in rotordynamics software. The uncertainty of the MC and its significant influence on static and dynamic response predictions emphasizes a need to utilize the CFD approach for TPJB simulation in critical machines.

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Spin-polarized electron liquid at arbitrary temperatures: Exchange-correlation energies, electron-distribution functions, and the static response functions

Physical Review B ◽

10.1103/physrevb.62.16536 ◽

2000 ◽

Vol 62 (24) ◽

pp. 16536-16548 ◽

Cited By ~ 110

Author(s):

François Perrot ◽

M. W. C. Dharma-wardana

Keyword(s):

Electron Distribution ◽

Distribution Functions ◽

Response Functions ◽

Static Response ◽

Exchange Correlation ◽

Spin Polarized

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Why Is Mind-Wandering Interesting for Philosophers?

10.1093/oxfordhb/9780190464745.013.32 ◽

2018 ◽

Cited By ~ 1

Author(s):

Thomas Metzinger

Keyword(s):

Empirical Research ◽

Philosophy Of Mind ◽

Mind Wandering ◽

Conceptual Level ◽

Specific Target ◽

Fine Grained ◽

Theories Of Mind ◽

Self Knowledge ◽

Spontaneous Thought

This chapter explores points of contact between philosophy of mind and scientific approaches to spontaneous thought. While offering a series of conceptual instruments that might prove helpful for researchers on the empirical research frontier, it begins by asking what the explanandum for theories of mind-wandering is, how one can conceptually individuate single occurrences of this specific target phenomenon, and how one might arrive at a more fine-grained taxonomy. The second half of this contribution sketches some positive proposals as to how one might understand mind-wandering on a conceptual level, namely, as a loss of mental autonomy resulting in involuntary mental behavior, as a highly specific epistemic deficit relating to self-knowledge, and as a discontinuous phenomenological process in which one’s conscious “unit of identification” is switched.

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Cognitive Control along the Language Spectrum: From the Typical Bilingual Child to Language Impairment

Seminars in Speech and Language ◽

10.1055/s-0039-1692962 ◽

2019 ◽

Vol 40 (04) ◽

pp. 256-271

Author(s):

Klara Marton ◽

Thorfun Gehebe ◽

Lia Pazuelo

Keyword(s):

Cognitive Control ◽

Language Processing ◽

Language Impairment ◽

Cognitive Skills ◽

Critical Role ◽

Bilingual Children ◽

Interference Control ◽

Negative Effects ◽

Control Functions ◽

Language Deficit

AbstractCognitive control refers to the ability to perform goal-directed behaviors in the presence of other compelling actions or in the face of habitual practices. Cognitive control functions play a critical role in children's language processing and literacy development. In recent years, many clinicians have expanded their assessment and treatment to target specific cognitive skills. Our goal is to provide a review of recent findings on cognitive control functions in children with different language status (i.e., monolingual and bilingual children with and without language impairment). While children with language impairment show performance deficits in specific cognitive functions (e.g., working memory updating and interference control), typically developing bilingual children often outperform their monolingual peers in cognitive control tasks. However, the relationship between bilingualism and cognitive control has been controversial. Several factors that influence these variations are discussed. Given the findings on the joint impact of bilingualism and language impairment on cognitive control functions, we identify conditions in which bilingualism attenuates the negative effects of the language deficit and conditions in which language impairment has a stronger effect than bilingualism. Critical issues of bilingual assessment, suggestions, and future directions are discussed.

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