Mind blanking is associated with a rigid spatio-temporal profile in typical wakefulness

Mind-blanking (MB) is the inability to report mental contents, challenging the view of a constantly thought-oriented mind during wakefulness. Using fMRI experience-sampling we show that MB is reported scarcely, fast, and has low transitional dynamics, pointing to its role as a transient mental relay. MB's cerebral profile is linked to an overall positive connectivity pattern, bearing great resemblance to neural configurations observed in local sleeps, possibly reflecting neuronal silencing during wakefulness. We also find less efficient information flow between the default mode (DMN) and other networks before reporting MB. The DMN-salience network segregation was further able to classify MB from other reports in fewer steps, suggestive of an early saliency evaluation of contentless phenomenology along the neurocognitive hierarchy. Collectively, MB's unique neurofunctional profile among thought-oriented reports supports the view of instantaneous mental absences happening during wakefuless, paving the way for more mechanistic investigations of this particular phenomenology during ongoing mentation.

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Macroscopic cortical dynamics: Spatially uncorrelated but temporally coherent rich-club organisations in source-space resting-state EEG

10.1101/2020.07.23.217786 ◽

2020 ◽

Author(s):

Steve Mehrkanoon

Keyword(s):

Functional Connectivity ◽

Resting State ◽

Complex Dynamics ◽

Cortical Activity ◽

Computational Technique ◽

Salience Network ◽

Resting State Functional Connectivity ◽

Default Mode ◽

Rich Club ◽

Topological Features

AbstractSynchronous oscillations of neuronal populations support resting-state cortical activity. Recent studies indicate that resting-state functional connectivity is not static, but exhibits complex dynamics. The mechanisms underlying the complex dynamics of cortical activity have not been well characterised. Here, we directly apply singular value decomposition (SVD) in source-reconstructed electroencephalography (EEG) in order to characterise the dynamics of spatiotemporal patterns of resting-state functional connectivity. We found that changes in resting-state functional connectivity were associated with distinct complex topological features, “Rich-Club organisation”, of the default mode network, salience network, and motor network. Rich-club topology of the salience network revealed greater functional connectivity between ventrolateral prefrontal cortex and anterior insula, whereas Rich-club topologies of the default mode networks revealed bilateral functional connectivity between fronto-parietal and posterior cortices. Spectral analysis of the dynamics underlying Rich-club organisations of these source-space network patterns revealed that resting-state cortical activity exhibit distinct dynamical regimes whose intrinsic expressions contain fast oscillations in the alpha-beta band and with the envelope-signal in the timescale of < 0.1 Hz. Our findings thus demonstrated that multivariate eigen-decomposition of source-reconstructed EEG is a reliable computational technique to explore how dynamics of spatiotemporal features of the resting-state cortical activity occur that oscillate at distinct frequencies.

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CLUSTER–STAFF search coil magnetometer calibration – comparisons with FGM

Geoscientific Instrumentation Methods and Data Systems ◽

10.5194/gi-3-153-2014 ◽

2014 ◽

Vol 3 (2) ◽

pp. 153-177 ◽

Cited By ~ 6

Author(s):

P. Robert ◽

N. Cornilleau-Wehrlin ◽

R. Piberne ◽

Y. de Conchy ◽

C. Lacombe ◽

...

Keyword(s):

Transfer Functions ◽

Low Frequency ◽

Temporal Analysis ◽

Fluxgate Magnetometer ◽

Data Sets ◽

Spectral Matrix ◽

Spatio Temporal ◽

Cross Calibration ◽

The Waves ◽

The Way

Abstract. The main part of the Cluster Spatio-Temporal Analysis of Field Fluctuations (STAFF) experiment consists of triaxial search coils allowing the measurements of the three magnetic components of the waves from 0.1 Hz up to 4 kHz. Two sets of data are produced, one by a module to filter and transmit the corresponding waveform up to either 10 or 180 Hz (STAFF-SC), and the second by the onboard Spectrum Analyser (STAFF-SA) to compute the elements of the spectral matrix for five components of the waves, 3 × B and 2 × E (from the EFW experiment), in the frequency range 8 Hz to 4 kHz. In order to understand the way the output signals of the search coils are calibrated, the transfer functions of the different parts of the instrument are described as well as the way to transform telemetry data into physical units across various coordinate systems from the spinning sensors to a fixed and known frame. The instrument sensitivity is discussed. Cross-calibration inside STAFF (SC and SA) is presented. Results of cross-calibration between the STAFF search coils and the Cluster Fluxgate Magnetometer (FGM) data are discussed. It is shown that these cross-calibrations lead to an agreement between both data sets at low frequency within a 2% error. By means of statistics done over 10 yr, it is shown that the functionalities and characteristics of both instruments have not changed during this period.

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Localized mechanical stimulation of single cells with engineered spatio-temporal profile

Lab on a Chip ◽

10.1039/c8lc00393a ◽

2018 ◽

Vol 18 (19) ◽

pp. 2955-2965 ◽

Cited By ~ 1

Author(s):

M. Monticelli ◽

D. S. Jokhun ◽

D. Petti ◽

G. V. Shivashankar ◽

R. Bertacco

Keyword(s):

Cell Culture ◽

Mechanical Stimulation ◽

Single Cells ◽

Mechanical Stimuli ◽

Temporal Profile ◽

A Cell ◽

Spatio Temporal ◽

Stimulation Of

We introduce a new platform for mechanobiology based on active substrates, made of Fe-coated polymeric micropillars, capable to apply mechanical stimuli with tunable spatio-temporal profile on a cell culture.

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Efficient Information Flow Based on Graphical Network Characteristics

Proceedings of the International Conference on Paradigms of Computing, Communication and Data Sciences - Algorithms for Intelligent Systems ◽

10.1007/978-981-15-7533-4_40 ◽

2021 ◽

pp. 515-526

Author(s):

Rahul Saxena ◽

Mahipal Jadeja ◽

Atul Kumar Verma

Keyword(s):

Information Flow ◽

Network Characteristics ◽

Efficient Information

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Projectivism

Routledge Encyclopedia of Philosophy ◽

10.4324/9780415249126-n048-1 ◽

2018 ◽

Author(s):

Simon Blackburn

Keyword(s):

Twentieth Century ◽

Scientific Theory ◽

Temporal Order ◽

The World ◽

Great Propensity ◽

Spatio Temporal ◽

The Mind ◽

Modern Era ◽

The Way

‘Projectivism’ is used of philosophies that agree with Hume that ‘the mind has a great propensity to spread itself on the world’, that what is in fact an aspect of our own experience or of our own mental organization is treated as a feature of the objective order of things. Such philosophies distinguish between nature as it really is, and nature as we experience it as being. The way we experience it as being is thought of as partly a reflection or projection of our own natures. The projectivist might take as a motto the saying that beauty lies in the eye of the beholder, and seeks to develop the idea and explore its implications. The theme is a constant in the arguments of the Greek sceptics, and becomes almost orthodox in the modern era. In Hume it is not only beauty that lies in the eye (or mind) of the beholder, but also virtue, and causation. In Kant the entire spatio-temporal order is not read from nature, but read into it as a reflection of the organization of our minds. In the twentieth century it has been especially non-cognitive and expressivist theories of ethics that have adopted the metaphor, it being fairly easy to see how we might externalize or project various sentiments and attitudes onto their objects. But causation, probability, necessity, the stances we take towards each other as persons, even the temporal order of events and the simplicity of scientific theory have also been candidates for projective treatment.

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