Automated 3-D Computer-Aided Measurement of the Bony Orbit: Evaluation of Correlations among Volume, Depth, and Surface Area.

(1)The study aimed to measure the depth, volume, and surface area of the intact human orbit by applying an automated method of CT segmentation and to evaluate correlations among depth, volume, and surface area. Additionally, the relative increases in volume and surface area in proportion to the diagonal of the orbit were assessed. (2) CT data from 174 patients were analyzed.

Cost of focality in TDCS: Interindividual variability in electric fields.

Background: In transcranial direct current stimulation (TDCS), electric current is applied via two large electrodes to modulate brain activity. Computational models have shown that large electrodes produce diffuse electric fields (EFs) in the brain, which depends on individual head and brain anatomy. Recently, smaller electrodes as well as novel electrode arrangements, including high-definition TDCS (HD-TDCS) montages, have been introduced to improve the focality of EFs.

Group-level and functional-region analysis of electric-field shape during cerebellar transcranial direct current stimulation with different electrode montages.

Objective: Cerebellar transcranial direct current stimulation (ctDCS) is a neuromodulation scheme that delivers a small current to the cerebellum. In this work, we computationally investigate the distributions and strength of the stimulation dosage during ctDCS with the aim of determining the targeted cerebellar regions of a group of subjects with different electrode montages.

Approach: We used a new inter-individual registration method that permitted the projection of computed electric fields (EFs) from individual realistic head models (n  =  18) to standard cerebellar template for the first time.

Effects of posture on electric fields of non-invasive brain stimulation.

The brain moves when the orientation of the head changes. This inter-postural motion has been shown to affect the distribution of cerebrospinal fluid (CSF). As CSF layer thickness affects the distribution of electric fields (EF) in non-invasive brain stimulation methods such as transcranial direct current (TDCS) and magnetic (TMS) stimulation, possible differences in body position between sessions could affect the stimulation efficacy.

Can electric fields explain inter-individual variability in transcranial direct current stimulation of the motor cortex?

The effects of transcranial direct current stimulation (tDCS) on motor cortical excitability are highly variable between individuals. Inter-individual differences in the electric fields generated in the brain by tDCS might play a role in the variability. Here, we explored whether these fields are related to excitability changes following anodal tDCS of the primary motor cortex (M1).

A multi-scale computational approach based on TMS experiments for the assessment of electro-stimulation thresholds of the brain at intermediate frequencies.

In recent years, human exposure to electromagnetic fields (EMF) at intermediate frequencies (300 Hz-10 MHz) has risen, mainly due to the growth of technologies using these fields. The current safety guidelines/standards defined by international bodies (e.g.

TMS Motor Thresholds Correlate With TDCS Electric Field Strengths in Hand Motor Area.

Transcranial direct current stimulation (TDCS) modulates cortical activity and influences motor and cognitive functions in both healthy and clinical populations. However, there is large inter-individual variability in the responses to TDCS. Computational studies have suggested that inter-individual differences in cranial and brain anatomy may contribute to this variability via creating varying electric fields in the brain.

Choice of osteoblast model critical for studying the effects of electromagnetic stimulation on osteogenesis in vitro.

The clinical benefits of electromagnetic field (EMF) therapy in enhancing osteogenesis have been acknowledged for decades, but agreement regarding the underlying mechanisms continues to be sought. Studies have shown EMFs to promote osteoblast-like cell proliferation, or contrarily, to induce differentiation and enhance mineralization. Typically these disparities have been attributed to methodological differences.

Electric fields of motor and frontal tDCS in a standard brain space: A computer simulation study.

The electric field produced in the brain is the main physical agent of transcranial direct current stimulation (tDCS). Inter-subject variations in the electric fields may help to explain the variability in the effects of tDCS. Here, we use multiple-subject analysis to study the strength and variability of the group-level electric fields in the standard brain space.