Effects of electrical brain stimulation on brain indices and presence experience in immersive, interactive virtual reality

AbstractThe subjective presence experience in virtual reality (VR) is associated with distinct brain activation patterns. Particularly, the dorsolateral prefrontal cortex (DLPFC) seems to play a central role. We investigated the effects of electric brain stimulation (transcranial direct current, tDCS) on the presence experience as well as on brain activity and connectivity. Thirty-eight participants received either anodal (N = 18) or cathodal (N = 20) stimulation of the DLPFC before interacting in an immersive VR as well as sham stimulation. During VR interaction, EEG and heart rate were recorded. After VR interaction, participants rated their subjective presence experience using standardized questionnaires. Cathodal stimulation led to stronger brain connectivity than sham stimulation. Increased brain connectivity was associated with numerically lower levels of subjective presence. Anodal stimulation did not lead to changes in brain connectivity, and no differences in subjective presence ratings were found between the anodal and sham stimulation. These results indicate that cathodal tDCS over the DLPFC leads to a more synchronized brain state, which might hamper the activity in networks, which are generally associated with the evolvement of the subjective presence experience. Our results underline the importance of the DLPFC for the presence experience in VR.

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Head models of healthy and depressed adults for simulating the electric fields of non-invasive electric brain stimulation

10.31234/osf.io/e5agy ◽

2018 ◽

Author(s):

Nya Mehnwolo Boayue ◽

Gábor Csifcsák ◽

Oula Puonti ◽

Axel Thielscher ◽

Matthias Mittner

Keyword(s):

Electric Fields ◽

Brain Stimulation ◽

Brain Anatomy ◽

Imaging Data ◽

Structural Variations ◽

Major Depressive ◽

Non Invasive ◽

The Past ◽

Dorsolateral Prefrontal ◽

Electric Brain Stimulation

During the past decade, it became clear that the electric field elicited by non-invasive brain stimulation (NIBS) techniques such as transcranial direct current stimulation (tDCS) and transcranial magnetic stimulation (TMS) are substantially influenced by variations in individual head and brain anatomy. In addition to structural variations in the healthy, several psychiatric disorders are characterized by anatomical alterations that are likely to further constrain the intracerebral effects of NIBS. Here, we present high-resolution realistic head models derived from structural magnetic resonance imaging data of 19 healthy adults and 19 patients diagnosed with major depressive disorder (MDD). By using a freely available software package for modelling the electric fields induced by different NIBS protocols, we show that our head models are well-suited for assessing inter-individual and between-group variability in the magnitude and focality of tDCS-induced electric fields for two protocols targeting the left dorsolateral prefrontal cortex.

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Head models of healthy and depressed adults for simulating the electric fields of non-invasive electric brain stimulation

F1000Research ◽

10.12688/f1000research.15125.2 ◽

2018 ◽

Vol 7 ◽

pp. 704 ◽

Cited By ~ 1

Author(s):

Nya Mehnwolo Boayue ◽

Gábor Csifcsák ◽

Oula Puonti ◽

Axel Thielscher ◽

Matthias Mittner

Keyword(s):

Electric Fields ◽

Brain Stimulation ◽

Brain Anatomy ◽

Imaging Data ◽

Structural Variations ◽

Major Depressive ◽

Non Invasive ◽

The Past ◽

Dorsolateral Prefrontal ◽

Electric Brain Stimulation

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Investigating the interaction between white matter and brain state on tDCS-induced changes in brain network activity

10.1101/2020.10.09.332742 ◽

2020 ◽

Author(s):

Danielle L. Kurtin ◽

Ines R. Violante ◽

Karl Zimmerman ◽

Robert Leech ◽

Adam Hampshire ◽

...

Keyword(s):

White Matter ◽

Brain Activity ◽

Inferior Frontal Gyrus ◽

Brain Networks ◽

Brain Network ◽

Network Activity ◽

Brain State ◽

State Dependent ◽

Cathodal Tdcs ◽

The Right

AbstractBackgroundTranscranial direct current stimulation (tDCS) is a form of noninvasive brain stimulation whose potential as a cognitive therapy is hindered by our limited understanding of how participant and experimental factors influence its effects. Using functional MRI to study brain networks, we have previously shown in healthy controls that the physiological effects of tDCS are strongly influenced by brain state. We have additionally shown, in both healthy and traumatic brain injury (TBI) populations, that the behavioral effects of tDCS are positively correlated with white matter (WM) structure.ObjectivesIn this study we investigate how these two factors, WM structure and brain state, interact to shape the effect of tDCS on brain network activity.MethodsWe applied anodal, cathodal and sham tDCS to the right inferior frontal gyrus (rIFG) of healthy (n=22) and TBI participants (n=34). We used the Choice Reaction Task (CRT) performance to manipulate brain state during tDCS. We acquired simultaneous fMRI to assess activity of cognitive brain networks and used Fractional Anisotropy (FA) as a measure of WM structure.ResultsWe find that the effects of tDCS on brain network activity in TBI participants are highly dependent on brain state, replicating findings from our previous healthy control study in a separate, patient cohort. We then show that WM structure further modulates the brain-state dependent effects of tDCS on brain network activity. These effects are not unidirectional – in the absence of task with anodal and cathodal tDCS, FA is positively correlated with brain activity in several regions of the default mode network. Conversely, with cathodal tDCS during CRT performance, FA is negatively correlated with brain activity in a salience network region.ConclusionsOur results show that experimental and participant factors interact to have unexpected effects on brain network activity, and that these effects are not fully predictable by studying the factors in isolation.

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Comparison of Four fMRI Paradigms Probing Emotion Processing

Brain Sciences ◽

10.3390/brainsci11050525 ◽

2021 ◽

Vol 11 (5) ◽

pp. 525

Author(s):

Corinna Hartling ◽

Sophie Metz ◽

Corinna Pehrs ◽

Milan Scheidegger ◽

Rebecca Gruzman ◽

...

Keyword(s):

Brain Activity ◽

Emotion Processing ◽

Brain Regions ◽

Anterior Insula ◽

Anterior Cingulate ◽

Future Research ◽

Activation Patterns ◽

Study Planning ◽

Dorsolateral Prefrontal ◽

The Right

Previous fMRI research has applied a variety of tasks to examine brain activity underlying emotion processing. While task characteristics are known to have a substantial influence on the elicited activations, direct comparisons of tasks that could guide study planning are scarce. We aimed to provide a comparison of four common emotion processing tasks based on the same analysis pipeline to suggest tasks best suited for the study of certain target brain regions. We studied an n-back task using emotional words (EMOBACK) as well as passive viewing tasks of emotional faces (FACES) and emotional scenes (OASIS and IAPS). We compared the activation patterns elicited by these tasks in four regions of interest (the amygdala, anterior insula, dorsolateral prefrontal cortex (dlPFC) and pregenual anterior cingulate cortex (pgACC)) in three samples of healthy adults (N = 45). The EMOBACK task elicited activation in the right dlPFC and bilateral anterior insula and deactivation in the pgACC while the FACES task recruited the bilateral amygdala. The IAPS and OASIS tasks showed similar activation patterns recruiting the bilateral amygdala and anterior insula. We conclude that these tasks can be used to study different regions involved in emotion processing and that the information provided is valuable for future research and the development of fMRI biomarkers.

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Current Directions in Non-Invasive Low Intensity Electric Brain Stimulation for Depressive Disorder

CNS & Neurological Disorders - Drug Targets ◽

10.2174/1871527313666140612115123 ◽

2014 ◽

Vol 13 (6) ◽

pp. 945-952 ◽

Cited By ~ 1

Author(s):

Dennis Schutter ◽

Alexander Sack

Keyword(s):

Depressive Disorder ◽

Brain Stimulation ◽

Non Invasive ◽

Low Intensity ◽

Electric Brain Stimulation

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Applying a Sensing-Enabled System for Ensuring Safe Anterior Cingulate Deep Brain Stimulation for Pain

Brain Sciences ◽

10.3390/brainsci9070150 ◽

2019 ◽

Vol 9 (7) ◽

pp. 150 ◽

Cited By ~ 5

Author(s):

Yongzhi Huang ◽

Binith Cheeran ◽

Alexander L. Green ◽

Timothy J. Denison ◽

Tipu Z. Aziz

Keyword(s):

Deep Brain Stimulation ◽

Pain Relief ◽

Brain Stimulation ◽

Brain Activity ◽

Anterior Cingulate ◽

Chronic Therapy ◽

Provide Pain Relief ◽

Surgical Options ◽

Effective Pain Relief ◽

Deep Brain

Deep brain stimulation (DBS) of the anterior cingulate cortex (ACC) was offered to chronic pain patients who had exhausted medical and surgical options. However, several patients developed recurrent seizures. This work was conducted to assess the effect of ACC stimulation on the brain activity and to guide safe DBS programming. A sensing-enabled neurostimulator (Activa PC + S) allowing wireless recording through the stimulating electrodes was chronically implanted in three patients. Stimulation patterns with different amplitude levels and variable ramping rates were tested to investigate whether these patterns could provide pain relief without triggering after-discharges (ADs) within local field potentials (LFPs) recorded in the ACC. In the absence of ramping, AD activity was detected following stimulation at amplitude levels below those used in chronic therapy. Adjustment of stimulus cycling patterns, by slowly ramping on/off (8-s ramp duration), was able to prevent ADs at higher amplitude levels while maintaining effective pain relief. The absence of AD activity confirmed from the implant was correlated with the absence of clinical seizures. We propose that AD activity in the ACC could be a biomarker for the likelihood of seizures in these patients, and the application of sensing-enabled techniques has the potential to advance safer brain stimulation therapies, especially in novel targets.

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The Neural Basis of Vivid Memory Is Patterned on Perception

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00253 ◽

2012 ◽

Vol 24 (9) ◽

pp. 1867-1883 ◽

Cited By ~ 41

Author(s):

Bradley R. Buchsbaum ◽

Sabrina Lemire-Rodger ◽

Candice Fang ◽

Hervé Abdi

Keyword(s):

Brain Activity ◽

Sensory Perception ◽

Direct Perception ◽

Neural Basis ◽

Activation Patterns ◽

Short Video ◽

Initial Perception ◽

Experiential Quality ◽

High Degree

When we have a rich and vivid memory for a past experience, it often feels like we are transported back in time to witness once again this event. Indeed, a perfect memory would exactly mimic the experiential quality of direct sensory perception. We used fMRI and multivoxel pattern analysis to map and quantify the similarity between patterns of activation evoked by direct perception of a diverse set of short video clips and the vivid remembering, with closed eyes, of these clips. We found that the patterns of distributed brain activation during vivid memory mimicked the patterns evoked during sensory perception. Using whole-brain patterns of activation evoked by perception of the videos, we were able to accurately classify brain patterns that were elicited when participants tried to vividly recall those same videos. A discriminant analysis of the activation patterns associated with each video revealed a high degree (explaining over 80% of the variance) of shared representational similarity between perception and memory. These results show that complex, multifeatured memory involves a partial reinstatement of the whole pattern of brain activity that is evoked during initial perception of the stimulus.

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An Analysis of the External Validity of EEG Spectral Power in an Uncontrolled Outdoor Environment during Default and Complex Neurocognitive States

Brain Sciences ◽

10.3390/brainsci11030330 ◽

2021 ◽

Vol 11 (3) ◽

pp. 330

Author(s):

Dalton J. Edwards ◽

Logan T. Trujillo

Keyword(s):

External Validity ◽

Spectral Power ◽

Brain Activity ◽

Outdoor Environment ◽

Oscillatory Activity ◽

Brain State ◽

Beta Band ◽

Eeg Spectral Power ◽

Eeg Power ◽

Human Participants

Traditionally, quantitative electroencephalography (QEEG) studies collect data within controlled laboratory environments that limit the external validity of scientific conclusions. To probe these validity limits, we used a mobile EEG system to record electrophysiological signals from human participants while they were located within a controlled laboratory environment and an uncontrolled outdoor environment exhibiting several moderate background influences. Participants performed two tasks during these recordings, one engaging brain activity related to several complex cognitive functions (number sense, attention, memory, executive function) and the other engaging two default brain states. We computed EEG spectral power over three frequency bands (theta: 4–7 Hz, alpha: 8–13 Hz, low beta: 14–20 Hz) where EEG oscillatory activity is known to correlate with the neurocognitive states engaged by these tasks. Null hypothesis significance testing yielded significant EEG power effects typical of the neurocognitive states engaged by each task, but only a beta-band power difference between the two background recording environments during the default brain state. Bayesian analysis showed that the remaining environment null effects were unlikely to reflect measurement insensitivities. This overall pattern of results supports the external validity of laboratory EEG power findings for complex and default neurocognitive states engaged within moderately uncontrolled environments.

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Visual Cortex Transcranial Direct Current Stimulation for Proliferative Diabetic Retinopathy Patients: A Double-Blinded Randomized Exploratory Trial

Brain Sciences ◽

10.3390/brainsci11020270 ◽

2021 ◽

Vol 11 (2) ◽

pp. 270

Author(s):

Angelito Braulio F. de Venecia ◽

Shane M. Fresnoza

Keyword(s):

Diabetic Retinopathy ◽

Visual Cortex ◽

Proliferative Diabetic Retinopathy ◽

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Vision Loss ◽

Sham Stimulation ◽

Direct Current Stimulation ◽

Residual Vision ◽

Cathodal Tdcs

Proliferative diabetic retinopathy (PDR) is a severe complication of diabetes. PDR-related retinal hemorrhages often lead to severe vision loss. The main goals of management are to prevent visual impairment progression and improve residual vision. We explored the potential of transcranial direct current stimulation (tDCS) to enhance residual vision. tDCS applied to the primary visual cortex (V1) may improve visual input processing from PDR patients’ retinas. Eleven PDR patients received cathodal tDCS stimulation of V1 (1 mA for 10 min), and another eleven patients received sham stimulation (1 mA for 30 s). Visual acuity (logarithm of the minimum angle of resolution (LogMAR) scores) and number acuity (reaction times (RTs) and accuracy rates (ARs)) were measured before and immediately after stimulation. The LogMAR scores and the RTs of patients who received cathodal tDCS decreased significantly after stimulation. Cathodal tDCS has no significant effect on ARs. There were no significant changes in the LogMAR scores, RTs, and ARs of PDR patients who received sham stimulation. The results are compatible with our proposal that neuronal noise aggravates impaired visual function in PDR. The therapeutic effect indicates the potential of tDCS as a safe and effective vision rehabilitation tool for PDR patients.

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Noninvasive brain stimulation for patients with a disorder of consciousness: a systematic review and meta-analysis

Reviews in the Neurosciences ◽

10.1515/revneuro-2020-0033 ◽

2020 ◽

Vol 31 (8) ◽

pp. 905-914 ◽

Cited By ~ 1

Author(s):

Yali Feng ◽

Jiaqi Zhang ◽

Yi Zhou ◽

Zhongfei Bai ◽

Ying Yin

Keyword(s):

Brain Stimulation ◽

Meta Analysis ◽

Minimally Conscious State ◽

Conscious State ◽

Primary Outcome Measure ◽

Noninvasive Brain Stimulation ◽

Disorder Of Consciousness ◽

Left Dlpfc ◽

Dorsolateral Prefrontal ◽

Minimally Conscious

AbstractNoninvasive brain stimulation (NIBS) techniques have been used to facilitate the recovery from prolonged unconsciousness as a result of brain injury. The aim of this study is to systematically assess the effects of NIBS in patients with a disorder of consciousness (DOC). We searched four databases for any randomized controlled trials on the effect of NIBS in patients with a DOC, which used the JFK Coma Recovery Scale-Revised (CRS-R) as the primary outcome measure. A random-effects meta-analysis was conducted to pool effect sizes. Fourteen studies with 273 participants were included in this review, of which 12 studies with sufficient data were included in the meta-analysis. Our meta-analysis showed a significant effect on increasing CRS-R scores in favor of real stimulation as compared to sham (Hedges’ g = 0.522; 95% confidence interval [CI], 0.318–0.726; P < 0.0001, I2 = 0.00%). Subgroup analysis demonstrated that only anodal transcranial direct current stimulation (tDCS) of the left dorsolateral prefrontal cortex (DLPFC) significantly enhances the CRS-R scores in patients with a DOC, as compared to sham (Hedges’ g = 0.703; 95% CI, 0.419–0.986; P < 0.001), and this effect was predominant in patients in a minimally conscious state (MCS) (Hedges’ g = 0.815; 95% CI, 0.429–1.200; P < 0.001). Anodal tDCS of the left DLPFC appears to be an effective approach for patients with MCS.

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