scholarly journals Intracranial EEG reveals bihemispheric parietal and extra parietal brain networks supporting mental arithmetic

2019 ◽  
Author(s):  
Gray Umbach ◽  
Michael Rugg ◽  
Gregory Worrell ◽  
Michael Sperling ◽  
Robert Gross ◽  
...  
Keyword(s):  
Temporal Dynamics ◽  
Mental Arithmetic ◽  
Mathematical Reasoning ◽  
Brain Regions ◽  
Hemispheric Differences ◽  
Simple Arithmetic ◽  
Data Set ◽  
Network Activation ◽  
Spatial And Temporal Dynamics ◽  
Intracranial Electrodes

Mathematical reasoning is central to everyday life. Lesion data and functional MRI studies suggest that even simple arithmetic involves the coordination of multiple spatially diverse brain regions, but to date, math processing has not been well characterized using direct brain recordings, especially outside of the parietal cortex. To address this, we utilized an unparalleled data set of 310 subjects implanted with intracranial electrodes to investigate the spatial and temporal dynamics of arithmetic reasoning. Our data support the importance of regions previously implicated in numerosity such as the superior parietal lobule and intraparietal sulcus. However, we also identify contributions to arithmetic processing from regions such as the entorhinal cortex and temporal pole. Using the excellent bihemispheric coverage afforded by our data set and the precise temporal resolution of intracranial recordings, we characterize in detail the spatial and temporal characteristics of an arithmetic processing network, quantifying subtle hemispheric differences for selected regions. We also examine how activity in these regions predicts arithmetic ability and look for gender differences in the pattern of network activation. Our findings further define the complex network of regions involved in human arithmetical reasoning.

EEG frequency band sloreta sources during mental arithmetic compared to resting

2011 ◽  
Vol 26 (S2) ◽  
pp. 945-945 ◽  
Author(s):  
A. Theodoropoulou ◽  
S. Tei ◽  
D. Lehmann ◽  
P.L. Faber ◽  
F. Schlegel ◽  
...  
Keyword(s):  
Frequency Band ◽  
Current Density ◽  
Mental Arithmetic ◽  
Brain Regions ◽  
Gamma Activity ◽  
Simple Arithmetic ◽  
Frequency Bands ◽  
Head Surface ◽  
Before And After ◽  
Surface Eeg

IntroductionArithmetic reportedly involves left parietal areas.ObjectivesTo test this in independent groups of healthy persons.AimsWhich brain regions are activated / inhibited during mental arithmetic compared to task-free resting?MethodsWe examined four independent groups of healthy adults (N = 15, 14, 14, 23, respectively) during simple arithmetic (continuous subtraction of 7) and task-free resting before and after arithmetic, all with closed eyes. Multichannel head surface EEG (19–58 channels) was continually recorded, then recomputed (using sLORETA functional tomography) into current density for 6239 cortical voxels, for each of the eight EEG frequency bands (delta through gamma, 1.5–44 Hz). Pre- and post-arithmetic resting was averaged. Using paired t-tests, frequency band-wise normalized and log-transformed current density was compared between arithmetic and resting for each group. The resulting p-values were combined across groups using Fisher’s combination procedure. For each frequency band, sLORETA voxels differing between conditions at Fisher’s (across groups) p < 0.05 were computed into centers of gravity separately for increased and decreased activation.ResultsActivity that was stronger during arithmetic compared to resting had gravity centers in midline anterior regions for slow frequency bands (delta, theta, alpha-1) and in right posterior regions for fast frequency bands (alpha-2 through gamma). Activity that was weaker during arithmetic compared to resting was centered around left parietal areas for all eight frequency bands.ConclusionsThe results suggest that arithmetic compared to resting involves frontal inhibition coupled with increased right parietal activation, and left parietal reduced facilitatory and reduced inhibitory activity.

Look both ways: factors affecting roadkill probability in Blue-black Grassquits (Volatinia jacarina)

2020 ◽  
Vol 98 (9) ◽  
pp. 603-610
Author(s):  
C.M. Soares ◽  
R.I. Dias
Keyword(s):  
Temporal Dynamics ◽  
Weather Conditions ◽  
Mitigation Measures ◽  
Breeding Period ◽  
Data Set ◽  
Vehicle Collisions ◽  
Factors Affecting ◽  
Exotic Grasses ◽  
Spatial And Temporal Dynamics ◽  
And Control

The contribution of roads to human economic and social development contrasts with its impact on the environment and wildlife. One of the most significant impacts of roads is wildlife–vehicle collisions. Millions of individuals from numerous species are killed annually around the world. Here we investigated the spatial and temporal dynamics of road killing on a small neotropical bird, the Blue-black Grassquit (Volatinia jacarina (Linnaeus, 1766)). We used a data set of roadkill records collected between 2010 and 2015 to test the hypotheses that roadkills are concentrated during the breeding period of the species and that road features and weather conditions affect the likelihood of animal–vehicle collisions. We observed that the number of fatalities was temporally and spatially clustered. Roadkills were more frequent in warmer, rainy days with lower wind speed. Fatalities were more commonly associated with two-lane roads compared with dirt and four-lane roads. Given that Blue-black Grassquits are attracted to human-modified habitats, especially to artificial grasslands composed of exotic grasses usually found along the margins of roads, mitigation measures should focus on the management and control of grass populations. Roadside mowing may reduce areas where Blue-black Grassquits can establish territories, and consequently, reduce the activity of the species near roads.

Spatial and temporal dynamics of lexico-semantic processing in American Sign Language

2011 ◽  
Author(s):  
M. Leonard ◽  
N. Ferjan Ramirez ◽  
C. Torres ◽  
M. Hatrak ◽  
R. Mayberry ◽  
...  
Keyword(s):  
American Sign Language ◽  
Sign Language ◽  
Semantic Processing ◽  
Temporal Dynamics ◽  
American Sign ◽  
Spatial And Temporal Dynamics

Spatial and temporal dynamics of Pacific capelin Mallotus catervarius in the Gulf of Alaska: implications for ecosystem-based fisheries management

2020 ◽  
Vol 637 ◽  
pp. 117-140 ◽  
Author(s):  
DW McGowan ◽  
ED Goldstein ◽  
ML Arimitsu ◽  
AL Deary ◽  
O Ormseth ◽  
...  
Keyword(s):  
Temporal Dynamics ◽  
Marine Ecosystem ◽  
Gulf Of Alaska ◽  
Data Series ◽  
Limited Information ◽  
Important Species ◽  
Multiple Data ◽  
Spatial And Temporal Dynamics ◽  
Spawning Areas ◽  
Spatio Temporal

Pacific capelin Mallotus catervarius are planktivorous small pelagic fish that serve an intermediate trophic role in marine food webs. Due to the lack of a directed fishery or monitoring of capelin in the Northeast Pacific, limited information is available on their distribution and abundance, and how spatio-temporal fluctuations in capelin density affect their availability as prey. To provide information on life history, spatial patterns, and population dynamics of capelin in the Gulf of Alaska (GOA), we modeled distributions of spawning habitat and larval dispersal, and synthesized spatially indexed data from multiple independent sources from 1996 to 2016. Potential capelin spawning areas were broadly distributed across the GOA. Models of larval drift show the GOA’s advective circulation patterns disperse capelin larvae over the continental shelf and upper slope, indicating potential connections between spawning areas and observed offshore distributions that are influenced by the location and timing of spawning. Spatial overlap in composite distributions of larval and age-1+ fish was used to identify core areas where capelin consistently occur and concentrate. Capelin primarily occupy shelf waters near the Kodiak Archipelago, and are patchily distributed across the GOA shelf and inshore waters. Interannual variations in abundance along with spatio-temporal differences in density indicate that the availability of capelin to predators and monitoring surveys is highly variable in the GOA. We demonstrate that the limitations of individual data series can be compensated for by integrating multiple data sources to monitor fluctuations in distributions and abundance trends of an ecologically important species across a large marine ecosystem.

scholarly journals Simultaneous spatiotemporal super-resolution and multi-parametric fluorescence microscopy

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jagadish Sankaran ◽  
Harikrushnan Balasubramanian ◽  
Wai Hoh Tang ◽  
Xue Wen Ng ◽  
Adrian Röllin ◽  
...  
Keyword(s):  
Single Molecule ◽  
Temporal Dynamics ◽  
Growth Factor Receptor ◽  
Super Resolution ◽  
Actin Binding ◽  
Biological Knowledge ◽  
Data Set ◽  
Epidermal Growth ◽  
Molecular Brightness ◽  
Super Resolution Microscopy

AbstractSuper-resolution microscopy and single molecule fluorescence spectroscopy require mutually exclusive experimental strategies optimizing either temporal or spatial resolution. To achieve both, we implement a GPU-supported, camera-based measurement strategy that highly resolves spatial structures (~100 nm), temporal dynamics (~2 ms), and molecular brightness from the exact same data set. Simultaneous super-resolution of spatial and temporal details leads to an improved precision in estimating the diffusion coefficient of the actin binding polypeptide Lifeact and corrects structural artefacts. Multi-parametric analysis of epidermal growth factor receptor (EGFR) and Lifeact suggests that the domain partitioning of EGFR is primarily determined by EGFR-membrane interactions, possibly sub-resolution clustering and inter-EGFR interactions but is largely independent of EGFR-actin interactions. These results demonstrate that pixel-wise cross-correlation of parameters obtained from different techniques on the same data set enables robust physicochemical parameter estimation and provides biological knowledge that cannot be obtained from sequential measurements.

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