scholarly journals Electrophysiological aftereffects of high-frequency transcranial random noise stimulation (hf-tRNS): an EEG investigation

Author(s):  
Filippo Ghin ◽  
Louise O’Hare ◽  
Andrea Pavan

AbstractThere is evidence that high-frequency transcranial random noise stimulation (hf-tRNS) is effective in improving behavioural performance in several visual tasks. However, so far there has been limited research into the spatial and temporal characteristics of hf-tRNS-induced facilitatory effects. In the present study, electroencephalogram (EEG) was used to investigate the spatial and temporal dynamics of cortical activity modulated by offline hf-tRNS on performance on a motion direction discrimination task. We used EEG to measure the amplitude of motion-related VEPs over the parieto-occipital cortex, as well as oscillatory power spectral density (PSD) at rest. A time–frequency decomposition analysis was also performed to investigate the shift in event-related spectral perturbation (ERSP) in response to the motion stimuli between the pre- and post-stimulation period. The results showed that the accuracy of the motion direction discrimination task was not modulated by offline hf-tRNS. Although the motion task was able to elicit motion-dependent VEP components (P1, N2, and P2), none of them showed any significant change between pre- and post-stimulation. We also found a time-dependent increase of the PSD in alpha and beta bands regardless of the stimulation protocol. Finally, time–frequency analysis showed a modulation of ERSP power in the hf-tRNS condition for gamma activity when compared to pre-stimulation periods and Sham stimulation. Overall, these results show that offline hf-tRNS may induce moderate aftereffects in brain oscillatory activity.

2015 ◽  
Vol 15 (1) ◽  
pp. 5-5 ◽  
Author(s):  
J. C. A. Read ◽  
R. Georgiou ◽  
C. Brash ◽  
P. Yazdani ◽  
R. Whittaker ◽  
...  

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Peter M. Kreuzer ◽  
Timm B. Poeppl ◽  
Rainer Rupprecht ◽  
Veronika Vielsmeier ◽  
Astrid Lehner ◽  
...  

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Beatrice Moret ◽  
Rita Donato ◽  
Massimo Nucci ◽  
Giorgia Cona ◽  
Gianluca Campana

Abstract Transcranial random noise stimulation (tRNS) is a recent neuromodulation protocol. The high-frequency band (hf-tRNS) has shown to be the most effective in enhancing neural excitability. The frequency band of hf-tRNS typically spans from 100 to 640 Hz. Here we asked whether both the lower and the higher half of the high-frequency band are needed for increasing neural excitability. Three frequency ranges (100–400 Hz, 400–700 Hz, 100–700 Hz) and Sham conditions were delivered for 10 minutes at an intensity of 1.5 mA over the primary motor cortex (M1). Single-pulse transcranial magnetic stimulation (TMS) was delivered over the same area at baseline, 0, 10, 20, 30, 45 and 60 minutes after stimulation, while motor evoked potentials (MEPs) were recorded to evaluate changes in cortical excitability. Only the full-band condition (100–700 Hz) was able to modulate excitability by enhancing MEPs at 10 and 20 minutes after stimulation: neither the higher nor the lower sub-range of the high-frequency band significantly modulated cortical excitability. These results show that the efficacy of tRNS is strictly related to the width of the selected frequency range.


2017 ◽  
Author(s):  
Chris Allen

AbstractDo brain oscillations limit the temporal dynamics of experience? This pre-registered study used the separation of auditory stimuli to track perceptual experience and related this to oscillatory activity using magnetoencephalography. The rates at which auditory stimuli could be individuated matched the rates of oscillatory brain activity. Stimuli also entrained brain activity at the frequencies at which they were presented and a progression of high frequency gamma band events appeared to predict successful separation. These findings support a generalised function for brain oscillations, across frequency bands, in the alignment of activity to delineate representations.


2020 ◽  
Author(s):  
Bhuvanesh Awasthi

This study used high frequency transcranial Random Noise Stimulation (tRNS) to examine how low and high spatial frequency filtered faces are processed. In a response time behavioral task, healthy young adults categorized male and female faces, presented at fovea and periphery in alternate blocks, while sham and high frequency random noise was applied to occipito-parietal location on their scalp. Both the frequentist and bayesian approaches show that stimulation at the right occipito-temporal cortex significantly reduced response times to peripherally presented low spatial frequency information. This finding points to a possible plasticity in targeted regions induced by non-invasive neuromodulation of spatial frequency information in rapid perception of faces.


2021 ◽  
Vol 132 ◽  
pp. 116-122
Author(s):  
Martin Schecklmann ◽  
Vahid Nejati ◽  
Timm B. Poeppl ◽  
Juliette Peytard ◽  
Rainer Rupprecht ◽  
...  

2015 ◽  
Vol 25 (11) ◽  
pp. 4334-4340 ◽  
Author(s):  
Aleksandra Romanska ◽  
Constantin Rezlescu ◽  
Tirta Susilo ◽  
Bradley Duchaine ◽  
Michael J. Banissy

2014 ◽  
Vol 14 (10) ◽  
pp. 553-553 ◽  
Author(s):  
M. Banissy ◽  
B. Duchaine ◽  
T. Susilo ◽  
C. Rezlescu ◽  
A. Romanska

Perception ◽  
1996 ◽  
Vol 25 (1_suppl) ◽  
pp. 68-68
Author(s):  
H S Hock ◽  
K Kogan ◽  
N Lodes

In classical apparent motion, a spot of light is presented in alternation such that the waveforms describing the varying luminance at each of two locations are 180° out of phase. However, when the luminance variation at each location is approximately sinusoidal, and the perceiver's task is to discriminate motion direction, the optimum temporal phase is 90° (van Santen and Sperling, 1984 Journal of the Optical Society of America A1 451 – 473). The results reported in this study suggest that the optimality of the 90° temporal phase may be specific to the direction-discrimination task. Our experiments were based on a new procedure for measuring classical apparent motion thresholds (Hock, Kogan, and Espinoza, 1996, paper presented at ARVO). Two horizontally displaced dots are presented simultaneously against a darker background. The luminance ( L1) of one dot is always greater than that of the other ( L2), and the luminance values for the dots are exchanged on successive frames. Whether motion or stationarity is perceived depends on the background-relative luminance contrast (BRLC): ( L1- L2) divided by the difference between the average [( L1+ L2)/2] and background luminance. We found in the current study that motion thresholds depend on the temporal phase of the luminance variation at each location (rather than temporal asynchrony); the greater the phase difference (from 41° to 180°) the less the BRLC required for motion perception. At suprathreshold BRLC values, the perceived speed of apparent motion decreases with increased differences in temporal phase. The results are discussed in terms of Reichardt-type motion detection models.


Sign in / Sign up

Export Citation Format

Share Document