Journal: Scientific Reports

Article Title: Structural Connectivity Variances Underlie Functional and Behavioral Changes During Pain Relief Induced by Neuromodulation

doi: 10.1038/srep41603

Figure Lengend Snippet: Pain intensity ratings were recorded immediately before and after sham and anodal tDCS. The numerical rating scale was anchored between the extremes of 0 (“None”) and 10 (“Worst Imaginable”). Greater analgesia was found with anodal tDCS compared to sham tDCS (ANOVA stimulation by time interaction effect F (1,17) = 4.460, p < 0.05). A significant reduction was also observed in anodal tDCS trials (p = 0.04) but not in sham tDCS trials (p = 0.65). (*indicates p < 0.05).

Article Snippet: An MR-compatible tDCS kit (DC-Stimulator MR, Magstim, Cardiff, UK) was used, which was fitted with a pair of 5 kΩ resistors by the electrodes (7 cm × 5 cm) to prevent the occurrence of eddy currents or significant electrode heating in an MR setting.

Techniques:

Journal: Scientific Reports

Article Title: Structural Connectivity Variances Underlie Functional and Behavioral Changes During Pain Relief Induced by Neuromodulation

doi: 10.1038/srep41603

Figure Lengend Snippet: ( A ) Perfusion activity map of gray matter associated with Sham [Stimulation−Pre-stimulation] − Anodal [Stimulation−Pre-stimulation] (mixed effects; Z > 2). The sham session showed higher (in yellow-red) rCBF to left posterior insula and left thalamus and lower (in blue) rCBF to the left M1 than the anodal session. The striking lateralization of significant rCBF changes suggests that the modulations originated from anodal tDCS of L-DLPFC. ( B ) Due to the positive relationship between ongoing pain and posterior insula activity, the perfusion time course of the activated voxels in the left posterior insula was extracted for illustrative purposes. Despite temporal variations across the periods, the rCBF of posterior insula was consistently higher for the sham session than for the anodal session after their respective pre-stimulation period. This finding supports the behavioral pain ratings reported by the research volunteers. All perfusion percentages were compared to the mean time course value of the pre-stimulation period in the respective stimulation session. The data points were smoothed with a moving average filter (period = 1 minute). (*indicates p < 0.05).

Article Snippet: An MR-compatible tDCS kit (DC-Stimulator MR, Magstim, Cardiff, UK) was used, which was fitted with a pair of 5 kΩ resistors by the electrodes (7 cm × 5 cm) to prevent the occurrence of eddy currents or significant electrode heating in an MR setting.

Techniques: Activity Assay

Journal: Scientific Reports

Article Title: Structural Connectivity Variances Underlie Functional and Behavioral Changes During Pain Relief Induced by Neuromodulation

doi: 10.1038/srep41603

Figure Lengend Snippet: ( A ) For visualization purposes, axial slices of the mean probabilistic tracts between L-DLPFC (in blue) and left thalamus (in green) are shown. This mean probabilistic tract was used as a mask to derive individual’s FA within the L-DLPFC–thalamic tract. ( B ) There was a significant positive correlation between the mean FA within the L-DLPFC–thalamic tract and pain intensity decrease after anodal tDCS (Anodal [Pre-stimulation−Stimulation] ; r = 0.654, p < 0.01) but not during sham (Sham [Pre-stimulation−Stimulation] ; r = 0.300, p = 0.23). No data points were found to be outliers using Grubbs’ test (p < 0.01).

Article Snippet: An MR-compatible tDCS kit (DC-Stimulator MR, Magstim, Cardiff, UK) was used, which was fitted with a pair of 5 kΩ resistors by the electrodes (7 cm × 5 cm) to prevent the occurrence of eddy currents or significant electrode heating in an MR setting.

Techniques:

Journal: Scientific Reports

Article Title: Structural Connectivity Variances Underlie Functional and Behavioral Changes During Pain Relief Induced by Neuromodulation

doi: 10.1038/srep41603

Figure Lengend Snippet: ( A ) TBSS analysis describing the relationship between white matter integrity and tDCS induced pain intensity changes (i.e. Sham [Stimulation−Pre-stimulation] − Anodal [Stimulation−Pre-stimulation] ) across the whole white matter FA skeleton (in blue) (p < 0.05, FWE-corrected). ( B ) The only regions in which there was a significant correlation (in red-yellow) anatomically corresponded to the L-DLPFC-thalamic pathway identified using probabilistic tractography (in green; from ).

Article Snippet: An MR-compatible tDCS kit (DC-Stimulator MR, Magstim, Cardiff, UK) was used, which was fitted with a pair of 5 kΩ resistors by the electrodes (7 cm × 5 cm) to prevent the occurrence of eddy currents or significant electrode heating in an MR setting.

Techniques:

Journal: Scientific Reports

Article Title: Structural Connectivity Variances Underlie Functional and Behavioral Changes During Pain Relief Induced by Neuromodulation

doi: 10.1038/srep41603

Figure Lengend Snippet: ( A ) The relationship between structural and functional connectivity of L-DLPFC and thalamus during tDCS was investigated. The correlation between the two measures was significant for the anodal tDCS session (r = 0.485, p < 0.05) but not for the sham tDCS session (r = −0.094, p = 0.71). No data points were found to be outliers using Grubbs’ test (p < 0.01). ( B ) Activated voxels (in blue) from perfusion map between anodal and sham tDCS sessions (Sham [Stimulation−Pre-stimulation] − Anodal [Stimulation−Pre-stimulation] ; ) were overlaid on the white matter pathways identified using probabilistic tractography (in yellow-red). An overlap could be observed between the thresholded tracts and left thalamic voxels with rCBF changes.

Article Snippet: An MR-compatible tDCS kit (DC-Stimulator MR, Magstim, Cardiff, UK) was used, which was fitted with a pair of 5 kΩ resistors by the electrodes (7 cm × 5 cm) to prevent the occurrence of eddy currents or significant electrode heating in an MR setting.

Techniques: Functional Assay

Journal: Scientific Reports

Article Title: Structural Connectivity Variances Underlie Functional and Behavioral Changes During Pain Relief Induced by Neuromodulation

doi: 10.1038/srep41603

Figure Lengend Snippet: ( A ) Fifty-one healthy volunteers were first screened for their response to topical application of 1% capsaicin cream on the right, medial calf. To achieve optimal temporal resolution, a continuous rating scale, anchored between 0 (none) and 10 (worst imaginable) was used to record the subject’s ongoing pain intensity. After capsaicin application for 20–40 minutes, only subjects who reached and maintained a tonic pain experience (pain intensity rating of 5–7 for ≥30 minutes; ) participated in the remainder of the study. One subject withdrew due to discomfort during a sham tDCS MRI session. ( B ) Eighteen capsaicin responders participated in two perfusion MRI sessions, one with anodal tDCS and one with sham tDCS, at least one week apart. The order of the experimental sessions was randomized and counterbalanced across the subject cohort. Capsaicin cream was applied as in the initial screening session. No subjects reported pain before the session commenced. Once the subject’s pain intensity rating reached a score of 5, which typically required 20–40 minutes, a 5-minute pre-stimulation ASL fMRI scan was performed followed by a 20-minute scan with concurrent tDCS (anodal or sham). Subjects’ pain ratings were verbally recorded after each scan using the same numerical rating scale, as above. Prior to ASL fMRI scans, subjects also underwent a DTI scan in a previous session on a different day.

Article Snippet: An MR-compatible tDCS kit (DC-Stimulator MR, Magstim, Cardiff, UK) was used, which was fitted with a pair of 5 kΩ resistors by the electrodes (7 cm × 5 cm) to prevent the occurrence of eddy currents or significant electrode heating in an MR setting.

Techniques: Cream

Journal: Experimental Brain Research

Article Title: Neural changes associated with cerebellar tDCS studied using MR spectroscopy

doi: 10.1007/s00221-018-5170-1

Figure Lengend Snippet: Self-reported rate of attention, fatigue, quality of sleep (1 is poorest and 7 is the maximal), perceived tDCS as active (1) or sham (0) and sleep hours. All the values are averaged and compared using independent t tests between the groups, and presented as mean ± standard deviation (SD)

Article Snippet: Electrodes were connected to an MR-compatible tDCS machine (DC-Stimulator-MR, NeuroConn, Germany).

Techniques: Standard Deviation

Journal: Experimental Brain Research

Article Title: Neural changes associated with cerebellar tDCS studied using MR spectroscopy

doi: 10.1007/s00221-018-5170-1

Figure Lengend Snippet: Visuomotor adaptation task. a Experimental set up; participants sat behind a table facing a vertically orientated screen placed 105 cm in front of them. b Task protocol: Following 2 baseline blocks (each 96 trials: pre 1–2), an abrupt 30° VR was applied to the screen cursor and was maintained across 3 blocks (adapt 1–3). Cerebellar tDCS (anodal/sham) was applied from pre 2 until adapt 3 (pink). Following this, retention was examined by removing visual feedback (grey) for the final 3 blocks (post 1–3)

Article Snippet: Electrodes were connected to an MR-compatible tDCS machine (DC-Stimulator-MR, NeuroConn, Germany).

Techniques:

Journal: Experimental Brain Research

Article Title: Neural changes associated with cerebellar tDCS studied using MR spectroscopy

doi: 10.1007/s00221-018-5170-1

Figure Lengend Snippet: Graphical representation of MRS session using voxel localiser scans (T 2 ) and MEGA-PRESS pulse sequence. MRS data was acquired pre-, during, and post-tDCS (lasting 25 min each) performed sequentially within the same individually localised voxel

Article Snippet: Electrodes were connected to an MR-compatible tDCS machine (DC-Stimulator-MR, NeuroConn, Germany).

Techniques: Sequencing

Journal: Experimental Brain Research

Article Title: Neural changes associated with cerebellar tDCS studied using MR spectroscopy

doi: 10.1007/s00221-018-5170-1

Figure Lengend Snippet: MRS voxel localisation. a A single 2 × 2 × 2 cm voxel size was located manually in the posterior part of the right cerebellum underneath the anodal electrode. A cod liver oil capsule (yellow arrow) was situated at the top left edge of the electrode to assist with voxel localisation. Three sets of data were acquired: pre-, during and post- cerebellar tDCS; example MRS spectra are shown for three participants including N-acetylaspartate (NAA) and highlighting the ( b ) GABA and c GLX metabolite signals

Article Snippet: Electrodes were connected to an MR-compatible tDCS machine (DC-Stimulator-MR, NeuroConn, Germany).

Techniques:

Journal: Experimental Brain Research

Article Title: Neural changes associated with cerebellar tDCS studied using MR spectroscopy

doi: 10.1007/s00221-018-5170-1

Figure Lengend Snippet: Influence of cerebellar tDCS on visuomotor adaptation. Epoch data (average across 8 trials) for angular hand direction (˚) for the anodal (blue) and sham cerebellar tDCS groups. Positive values indicate CW hand direction. The inset bar graphs indicate mean hand direction for the anodal and sham groups during adaptation (adapt 1–3) and retention (post-1–3). Solid lines, mean; shaded areas/error bars, S.E.M

Article Snippet: Electrodes were connected to an MR-compatible tDCS machine (DC-Stimulator-MR, NeuroConn, Germany).

Techniques:

Journal: Experimental Brain Research

Article Title: Neural changes associated with cerebellar tDCS studied using MR spectroscopy

doi: 10.1007/s00221-018-5170-1

Figure Lengend Snippet: Cerebellar tDCS dependent changes in GABA and Glu. The average a GABA:H 2 O and b Glu:H 2 O ratio pre-, during and post-cerebellar tDCS. Change (%) in c GABA:H 2 O; d Glu:H 2 O during and post-cerebellar tDCS relative to baseline (pre-tDCS). The box-plot limits represent the 25th and 75th data percentiles and the middle line represents the median. The error bars represent the range of data

Article Snippet: Electrodes were connected to an MR-compatible tDCS machine (DC-Stimulator-MR, NeuroConn, Germany).

Techniques:

Journal: Experimental Brain Research

Article Title: Neural changes associated with cerebellar tDCS studied using MR spectroscopy

doi: 10.1007/s00221-018-5170-1

Figure Lengend Snippet: Correlations between MRS and visuomotor adaptation. a There was no significant correlation between the changes in the GABA:H20 ratio during cerebellar tDCS and total adaptation. The red line represents the sham group’s mean performance during total adaptation (shaded area = SD across group). b A significant negative correlation was observed between changes in the Glu:H2O ratio during cerebellar tDCS and total retention. The red line represents the sham group’s mean performance during total retention (shaded area = SD across group)

Article Snippet: Electrodes were connected to an MR-compatible tDCS machine (DC-Stimulator-MR, NeuroConn, Germany).

Techniques: