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Transcranial Electrical Stimulation for mTBI

Passive Electrical Neurofeedback Treatment of mTBI: MEG and Behavioral Outcomes

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03244475
Acronym
TESmTBI
Enrollment
66
Registered
2017-08-09
Start date
2017-02-01
Completion date
2022-09-30
Last updated
2024-01-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Mild Traumatic Brain Injury (mTBI), Post-traumatic Stress Disorder

Keywords

mild Traumatic Brain Injury, transcranial electrical stimulation, neurofeedback, magnetoencephalography, post-traumatic stress disorder

Brief summary

mTBI is a leading cause of sustained physical, cognitive, emotional, and behavioral deficits in OEF/OIF/OND Veterans and the general public. However, the underlying pathophysiology is not completely understood, and there are few effective treatments for post-concussive symptoms (PCS). In addition, there are substantial overlaps between PCS and PTSD symptoms in mTBI. IASIS is among a class of passive neurofeedback treatments that combine low-intensity pulses for transcranial electrical stimulation (LIP-tES) with EEG monitoring. Nexalin is another tES technique , with FDA approvals for treating insomnia, depression, and anxiety. LIP-tES techniques have shown promising results in alleviating PCS individuals with TBI. However, the neural mechanisms underlying the effects of LIP-tES treatment in TBI are unknown, owing to the dearth of neuroimaging investigations of this therapeutic intervention. Conventional neuroimaging techniques such as MRI and CT have limited sensitivity in detecting physiological abnormalities caused by mTBI, or in assessing the efficacy of mTBI treatments. In acute and chronic phases, CT and MRI are typically negative even in mTBI patients with persistent PCS. In contrast, evidence is mounting in support of resting-state magnetoencephalography (rs-MEG) slow-wave source imaging (delta-band, 1-4 Hz) as a marker for neuronal abnormalities in mTBI. The primary goal of the present application is to use rs-MEG to identify the neural underpinnings of behavioral changes associated with IASIS treatment in Veterans with mTBI. Using a double-blind placebo controlled design, the investigators will study changes in abnormal MEG slow-waves before and after IASIS treatment (relative to a 'sham' treatment group) in Veterans with mTBI. For a subset of participants who may have remaining TBI symptoms at the end of all IASIS treatment sessions, MEG slow-wave changes will be recorded before and after additional Nexalin treatment. In addition, the investigators will examine treatment-related changes in PCS, PTSD symptoms, neuropsychological test performances, and their association with changes in MEG slow-waves. The investigators for the first time will address a fundamental question about the mechanism of slow-waves in brain injury, namely whether slow-wave generation in wakefulness is merely a negative consequence of neuronal injury or if it is a signature of ongoing neuronal rearrangement and healing that occurs at the site of the injury.

Detailed description

Mild traumatic brain injury (mTBI) is a leading cause of sustained physical, cognitive, emotional, and behavioral deficits in OEF/OIF/OND Veterans and the general public. However, the underlying pathophysiology is not completely understood, and there are few effective treatments for post-concussive symptoms (PCS). In addition, there are substantial overlaps between PCS and post-traumatic stress disorder (PTSD) symptoms in mTBI. Furthermore, a substantial number of studies have shown higher (nearly double) rates of comorbid PTSD in individuals with mTBI, observed in military and civilian settings. IASIS is among a class of passive neurofeedback treatments that combine low-intensity pulses for transcranial electrical stimulation (LIP-tES) with electroencephalography (EEG) monitoring. Nexalin is another tES technique , with FDA approvals for treating insomnia, depression, and anxiety. LIP-tES techniques have shown promising results in alleviating PCS in individuals with TBI. However, the neural mechanisms underlying the effects of LIP-tES treatment in TBI are unknown, owing to the dearth of neuroimaging investigations of this therapeutic intervention. Conventional neuroimaging techniques such as MRI and CT have limited sensitivity in detecting physiological abnormalities caused by mTBI, or in assessing the efficacy of mTBI treatments. In acute and chronic phases, CT and MRI are typically negative even in mTBI patients with persistent PCS. In contrast, evidence is mounting in support of resting-state magnetoencephalography (rs-MEG) slow-wave source imaging as a non-invasive imaging marker for neuronal abnormalities in mTBI. Using region of interest (ROI) and voxel-wise approaches, the investigators demonstrated that MEG slowwave source imaging detects abnormal slow-waves (delta-band, 1-4 Hz) with \ 85% sensitivity in chronic and sub-acute mTBI patients with persistent PCS. The primary goal of the present application is to use rs- MEG to identify the neural underpinnings of behavioral changes associated with IASIS treatment in Veterans with mTBI. Using a double-blind placebo controlled design, the investigators will study changes in abnormal MEG slowwaves before and after IASIS treatment (relative to a 'sham' treatment group), and for a subset, before and after additional Nexalin treatment, in Veterans with mTBI. In addition, the investigators will examine treatment-related changes in PCS, PTSD symptoms, neuropsychological test performances, and their association with changes in MEG slow-waves. Pre-treatment baseline and posttreatment rs-MEG exams, symptoms assessments, and neuropsychological tests will be performed. The investigators for the first time will address a fundamental question about the mechanism of slow-waves in brain injury, namely whether slow-wave generation in wakefulness is merely a negative consequence of neuronal injury or if it is a signature of ongoing neuronal rearrangement and healing that occurs at the site of the injury. Specific Aim 1: To detect the loci of injury in Veterans with mTBI and assess the mechanisms underlying functional neuroimaging changes related to IASIS treatment, and for a subset of Veterans with remaining symptoms, additional Nexalin treatment, using rs-MEG slow-wave source imaging. The investigators' voxel-wise rs-MEG source-imaging technique will be used to identify abnormal slow-wave generation (delta band) in the baseline and post-treatment MEG exams to assess treatment-related changes on a single-subject basis. Healthy control (HC) Veterans, matched for combat exposure, will be used to establish an MEG normative database. Test-retest reliability of MEG slow-wave source imaging for mTBI will also be examined. Hypothesis 1: Veterans with mTBI will generate abnormal MEG slow-waves during the baseline MEG exam. Voxel-wise MEG slow-wave source imaging will show significantly higher sensitivity than conventional MRI in identifying the loci of injury on a single-subject basis. The test-retest reliability of MEG slow-wave source imaging is expected to be high, with intra-class correlation coefficient (ICC) 0.75 between two sequential MEG exams. Hypothesis 2: In wakefulness, slow-wave generation is a signature of ongoing neural rearrangement/ healing, rather than a negative consequence of neuronal injury. IASIS treatment will enhance neural rearrangement/healing by initially potentiating slow-wave generation immediately after each treatment session. Hypothesis 3: IASIS will ultimately reduce abnormal MEG slow-wave generation in mTBI by the end of the treatment course, owing to the accomplishment of neural rearrangement / healing. In Veterans with mTBI who finish IASIS treatment, but not in the sham group, MEG source imaging will show a significant decrease in abnormal slow-waves at post-treatment exam. Such significant decreases will also be evident in both the voxel-wise and overall abnormal MEG slow-wave measures. Specific Aim 2: To examine treatment-related changes in PCS and PTSD symptoms in Veterans with mTBI. PCS and PTSD symptoms will be assessed at the baseline and post-treatment follow-up visits. Hypothesis 4: Compared with the sham group, mTBI Veterans in the IASIS treatment group will show significantly greater decreases in PCS symptoms between baseline and post-treatment assessments. Hypothesis 5: Compared with the sham group, mTBI Veterans in the IASIS treatment group will also show significantly greater decreases in PTSD symptoms between baseline and post-treatment assessments. Specific Aim 3: To study the relationship among IASIS treatment-related changes in rs-MEG slow-wave imaging, PCS, and neuropsychological measures in Veterans with mTBI. The investigators will correlate changes between baseline and post-IASIS abnormal rs-MEG slow-wave generation (i.e., total abnormal rs-MEG slow-wave and voxel-wise source imaging measures) with changes in PCS and neuropsychological tests performance. Hypothesis 6: Reduced MEG slow-wave generation will correlate with reduced total PCS score, individual PCS scores (e.g., sleep disturbance, post-traumatic headache, photophobia, and memory problem symptoms), and improved neuropsychological exam scores between post-IASIS and baseline exams.

Interventions

DEVICETES

The EEG interface device is the J&J Engineering I-330 C2. IASIS is delivered via the 4 EEG leads with respect to the Common Neck Reference. During each session, 2 electrodes are attached to the participant's left and right mastoids, while the remaining 2 electrodes are moved to various locations on the scalp to record EEG signals. All 4 electrodes are involved in applying weak electric current pulses back to the brain. The feedback signal consists 2 types of narrow pulse trains, both with 150mV in amplitude. The Nexalin device, FDA clearance (501K=K024377, Classification: Stimulator, Cranial Electrotherapy: CFR 882. 5800: U.S. Patent #6904322B2), produces a waveform that provides tES to the brain delivered at a frequency of 4Hz, 40Hz, and 77.5Hz at 0 to 15mA peak current. Evidence shows this waveform, at these frequencies, results in improved clinical outcomes for anxiety and pain. We hypothesize that repeated TES treatments serve to stimulate long-term neurochemical changes.

Sponsors

San Diego Veterans Healthcare System
CollaboratorFED
VA Office of Research and Development
Lead SponsorFED

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Caregiver)

Masking description

Sham treatment, double-blind design: During the sham treatment, we will prep and preplace the electrodes for common reference, A-, B-, plus the set of electrodes on the scalp of the participant following the 10-20 EEG configuration for A+ and A-, just like the procedure for real TES treatment. However, no LIP-tES pulses will be sent from the system during sham treatment, based a code entered to the system. A staff member (SRA #1) will assign a mTBI Veteran to either the mTBI-TES or the mTBI Sham group, with an attached code from an existing code bank. Then, the TES treatment operator (SRA #2) who is blind to the group assignment will enter the code to the TES system during treatments. Based on the code, the system automatically loads the protocol for either TES or Sham treatment. Only at the end of the study (after V16), the group assignment is revealed. Therefore, both the participant and TES treatment operator (SRA #2) are blind to the group assignment during the study.

Intervention model description

After consent, Visit 1 (V1) for all 3 groups will include baseline NP and MHA. Then, baseline rs-MEG and MRI will be performed in V2 for all groups. At V3 the mTBI Veterans in TES and sham groups will undergo a pre-session MEG, the first TES/Sham treatment Session (S1), and a post-session MEG. Next, the mTBI Veterans continue their TES/Sham treatments S2-6 in V4-8. During V9, a pair of pre- and post-MEG exams and NP will be performed. The mTBI Veterans will continue treatments S8-11 in V10-13. During V14, a pair of pre- and post-MEG exams will be performed. 1 week after the Veterans finish their final TES/Sham treatment S12, a 1-week follow-up MEG and NP will be conducted during V15. A subset of TES group will be tested 1 month after the final treatment for a follow-up MEG V16. Veterans in the mTBI-sham group will be offered the real TES treatment.

Eligibility

Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
Yes

Inclusion criteria

Inclusion of Veterans for the mTBI groups: * All symptomatic mTBI patients will be evaluated in a clinical interview to document the nature of the injuries and ongoing PCS. * The diagnosis of mTBI patients is based on standard VA/DOD diagnostic criteria. * Inclusion in the mTBI patient group requires a TBI that meets the following criteria: * a loss of consciousness (LOC) \< 30 minutes or transient confusion, disorientation, or impaired consciousness immediately after the trauma * post-traumatic amnesia (PTA) \< 24 hours * an initial Glasgow Coma Scale (GCS) \[90\] between 13-15 (if available) * Since the GCS assessment is often not available in theater, Veterans with missing GCS, but who meet other inclusion criteria will also be recruited. * Each patient must have at least 3 items of persistent PCS at the beginning of the study. Inclusion of Healthy Control (HC) group: * Veterans that qualify as HCs will be age, education, combat exposure, and socioeconomically matched to the mTBI groups. * In addition to

Exclusion criteria

listed above, HC subjects must not have been diagnosed with head injury, affective disorder, or PTSD (CAPS-5 \< 8) throughout life.

Design outcomes

Primary

MeasureTime frameDescription
Change in Abnormal Magnetoencephalography (MEG) Slow-Waves (1-4 Hz) ActivityBaseline through end of treatment, an average of 6 weeksWe will develop a voxel-wise whole brain MEG source imaging approach for detecting abnormal Magnetoencephalography (MEG) slow-waves (1-4 Hz) in mTBI Veterans. The unit of the abnormal MEG source activity was measured in pico Ampere-meter (or pA-m which is 10\^(-12) A-m). Natural logarithm transformation (i.e., e-based) was used. So, the unit of the MEG source imaging was log(pA-m). The range of the voxel-wise MEG source activity scale is 0-10. High amplitude of the MEG source activity suggests more serious injury. In the present study, we measured the Difference score in MEG exam pre- vs post the transcranial electrical stimulation (TES) treatment. Our primary measure is the reduction of the abnormal MEG source activity for slow waves (1-4 Hz), defined as the MEG activity at the pre-TES exam minus that at the post-TES exam. So, the higher this difference score is, the better outcomes due to the TES treatment in reducing the abnormal MEG signal.
Rivermead Post Concussion Symptom QuestionnaireBaseline through end of treatment, an average of 6 weeksThe Rivermead Post Concussion Symptom Questionnaire (RPQ) total score was used to assess change in post-concussion symptoms due to TES. Our focus in this analysis was the difference score in RPQ total score pre- vs post-treatment measures. The questionnaire has 16 items and uses scale of 0 - 4, with 0 as not experienced at all and 4 as a severe problem. Value range: 0 - 64, where the higher scores mean a worse outcome. For this measure, we focused on the difference score: total score from prior to treatment minus total score from end of treatment. Therefore, the higher the difference score, the more positive change was observed.
Neurobehavioral Symptoms InventoryBaseline through end of treatment, an average of 6 weeksThe Neurobehavioral Symptoms Inventory (NSI) total score was used to assess the changes of post-concussion symptoms due to TES. Our focus in this analysis was the difference score in NSI total score pre- vs post-treatment measures. The NSI has 22 items and uses a response scale of 0 - 4, with 0 as none and 4 as very severe. Value range: 0 - 88, where the higher scores mean a worse outcome/more severe post-concussive symptoms. For this measure, we focused on the difference score: total score from prior to treatment minus total score from end of treatment. Therefore, the higher the difference score, the more positive change was observed.

Secondary

MeasureTime frameDescription
California Verbal Learning Test-2nd Edition - Free Recall Total Correct T-scoreUp to 6 weeksWe will use T-scores from verbal learning and retrospective memory (California Verbal Learning Test-2nd Edition). Alternate CVLT forms were used during the post-treatment session. T-score ranges from 5 to 95, where the higher the T-score, the better the outcome. The T-score indicates the number of standard deviations away from the mean, where 50 is the mean with a standard deviation of 10, and is age- and gender-corrected. Analysis was based on the difference score between pre-treatment and post-treatment Free Recall Total Correct T-score. The lower the difference score, the more positive change was observed.
Wechsler Adult Intelligence Scale-4th Edition (WAIS-IV) Processing Speed IndexUp to 6 weeksWe will use the sum of scaled scores from the WAIS-IV Symbol Search and Coding subtests to attain the Processing Speed Index. PSI ranged from 50 - 150, where the higher the score, the better the outcome. Analysis was based on the difference score between pre-treatment Processing Speed Index and post-treatment Processing Speed Index. The lower the difference score, the more positive change was observed.
Delis-Kaplan Executive Function System (DKEFS) - Trail Number/Letter Switching ScaledUp to 6 weeksThroughout the study, we used DKEFS Verbal Fluency, Trail-Making, and Color-Word Interference subtests to assess executive functioning. Analysis was based on the DKEFS Trailmaking Number/Letter Switching scaled score. Scaled scores range from 1-19, where the higher the scaled score, the better the outcome. Analysis was based on the difference score between pre-treatment scaled score and the post-treatment scaled score. The lower the difference score, the more positive change was observed.
The McGill Pain Questionnaire (MGPQ)Baseline through end of treatment, an average of 6 weeksThe McGill Pain Questionnaire (MGPQ) will evaluate the level of current pain, pain changes over time, and strength of pain, since pain is frequently co-morbid with mTBI. Category scores range from 1-2 through 1-6. Minimum score = 0. Maximum score = 78. The higher the pain score, the greater the pain. For this measure, we focused on the difference score: total score from prior to treatment minus total score from end of treatment. Therefore, the higher the difference score, the more positive change was observed.
Barratt Impulsivity ScaleUp to 6 weeksImpulsivity was also measured by Barratt Impulsivity Scale, a self-report questionnaire. This scale contains 30 items, with total scores that range from 30 - 120. The higher the score, the worse the outcome. Analysis was based on the difference score between pre- and post-treatment. The higher the difference score, the more positive change was observed.
Frontal Systems Behavior ScaleBaseline through end of treatment, an average of 6 weeksSince frontal lobe areas are more prone to damage, the Frontal Systems Behavior Scale (FrSBe) will measure behavioral dysfunction associated with frontal subcortical impairment. FrSBe is a 46-item rating scale with three subscales: Apathy (14 items), Disinhibition (15 items), and Executive Function (17 items). Items are rated in a 5-point scale, where higher scores mean a worse outcome. The raw scores of these subscales were converted to T-scores, with range of 9 - \>/= 140, where T-scores greater than 65 are considered clinically significant. For this measure, we focused on the difference score of the total T-score prior to treatment minus total score from end of treatment. Therefore, the higher the difference score, the more positive change was observed.
Connors Continuous Performance Task II (CPT-II) - Inattention Omissions T-ScoreUp to 6 weeksThe Connors Continuous Performance Task II (CPT-II) was included as a measure of attention and impulsivity. In this measure, converted T-scores represent the score of the individual relative to the population, who are of the same gender and same age group. A T-score of 50 represents the average for the comparison group. T-score ranges from under 40 (very good performance) to 65+ (markedly atypical). The higher the scores, the worse the performance. This analysis focused on the difference score between the Inattention Omissions T-score pre- and post-treatment. The higher the difference score, the more positive change was observed.
Clinician-Administered PTSD Scale (CAPS-5)Up to 6 weeksThe CAPS-5 is a standard semi-structured interview used to assess PTSD diagnosis and severity. The primary traumatic event is elicited and will be used as the basis of assessing PTSD symptoms. The total symptom severity score is calculated by summing severity scores assessed in this 30-item questionnaire. PTSD diagnostic status will be assessed using the past month version of the CAPS-5A, in which total severity score of 33 or higher indicates full threshold PTSD. The past week version of the CAPS-5 will be given prior to treatment and at follow-up. Severity scores range on a response scale of 0-5, 0=absent, 5=extreme/incapacitating. CAPS-55 summary scores range from 0 to 80, with the higher scores indicating greater severity of PTSD symptoms. For this measure, we focused on the difference score: total score from prior to treatment minus total score from end of treatment. Therefore, the higher the difference score, the more positive change was observed.
Post-Concussion Check List (PCL-5)Up to 6 weeksPCL-5 is a 20-item self-report measure that assesses the 20 DSM-5 symptoms of PTSD. The PCL-5 uses a response scale of 0 - 4. 0 = Not at all to 4 = Extremely. The total score can range from 0 - 80, with the higher the score corresponding to a higher level of distress to the very stressful experience. The difference between scores post-treatment and pre-treatment will analyzed in addition to the CAPS-5 (1 week version) outcomes. DSM-5 symptom cluster severity scores can be obtained by summing the scores for the items within a given cluster, i.e., cluster B (items 1-5), cluster C (items 6-7), cluster D (items 8-14), and cluster E (items 15-20); these subscale scores may be used in secondary analysis.

Countries

United States

Participant flow

Participants by arm

ArmCount
Transcranial Electrical Stimulation (TES)
mTBI Veterans blindly assigned to a 6-week IASIS neurofeedback treatment with two sessions per week. If participants in the mTBI group may have remaining PCS, additional Nexalin treatment will be offered. Nexalin TES will be administered once per day, Monday through Friday. Participants will receive 10-20 treatments, 3-4 times a week for 4 weeks, or up to 5 times a week for 4 weeks.
30
TES Sham Treatment
mTBI Veterans blindly assigned to a sham treatment for 6 weeks with two IASIS sessions per week or 10-20 Nexalin treatments, 3-4 times a week for 4 weeks or up to 5 times a week for 4 weeks.
17
Control
Veterans who are age-, gender-, education-, combat exposure-, and socioeconomically-matched. They will not undergo a treatment.
19
Total66

Baseline characteristics

CharacteristicTranscranial Electrical Stimulation (TES)TES Sham TreatmentControlTotal
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
0 Participants0 Participants0 Participants0 Participants
Age, Categorical
Between 18 and 65 years
30 Participants17 Participants19 Participants66 Participants
Age, Continuous38.17857143 years
STANDARD_DEVIATION 10.06072126
38.375 years
STANDARD_DEVIATION 6.945097192
39.68421053 years
STANDARD_DEVIATION 7.643728985
38.68253968 years
STANDARD_DEVIATION 8.677329332
Education Level15.03703704 years
STANDARD_DEVIATION 3.024363802
14.8125 years
STANDARD_DEVIATION 1.911110606
15.94736842 years
STANDARD_DEVIATION 2.139200151
15.25806452 years
STANDARD_DEVIATION 2.558574981
Ethnicity (NIH/OMB)
Hispanic or Latino
8 Participants1 Participants5 Participants14 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
22 Participants16 Participants14 Participants52 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants0 Participants
Handedness28 Participants Right Handed17 Participants Right Handed19 Participants Right Handed64 Participants Right Handed
Region of Enrollment
United States
30 Participants17 Participants19 Participants66 Participants
Sex: Female, Male
Female
1 Participants2 Participants1 Participants4 Participants
Sex: Female, Male
Male
29 Participants15 Participants18 Participants62 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
deaths
Total, all-cause mortality
0 / 380 / 170 / 19
other
Total, other adverse events
0 / 380 / 170 / 19
serious
Total, serious adverse events
0 / 380 / 170 / 19

Outcome results

Primary

Change in Abnormal Magnetoencephalography (MEG) Slow-Waves (1-4 Hz) Activity

We will develop a voxel-wise whole brain MEG source imaging approach for detecting abnormal Magnetoencephalography (MEG) slow-waves (1-4 Hz) in mTBI Veterans. The unit of the abnormal MEG source activity was measured in pico Ampere-meter (or pA-m which is 10\^(-12) A-m). Natural logarithm transformation (i.e., e-based) was used. So, the unit of the MEG source imaging was log(pA-m). The range of the voxel-wise MEG source activity scale is 0-10. High amplitude of the MEG source activity suggests more serious injury. In the present study, we measured the Difference score in MEG exam pre- vs post the transcranial electrical stimulation (TES) treatment. Our primary measure is the reduction of the abnormal MEG source activity for slow waves (1-4 Hz), defined as the MEG activity at the pre-TES exam minus that at the post-TES exam. So, the higher this difference score is, the better outcomes due to the TES treatment in reducing the abnormal MEG signal.

Time frame: Baseline through end of treatment, an average of 6 weeks

Population: \# of TES participants analyzed differs from the # of TES participants enrolled. mTBI veterans who were blindly placed in the TES Sham group had the option of completing TES sessions at the end of their original sessions. Therefore, some TES Sham participants opted to complete TES sessions, with questionnaires and pre-post MEG imaging.

ArmMeasureValue (MEAN)Dispersion
Transcranial Electrical Stimulation (TES)Change in Abnormal Magnetoencephalography (MEG) Slow-Waves (1-4 Hz) Activity1.8 units on a scaleStandard Deviation 1.2
TES Sham TreatmentChange in Abnormal Magnetoencephalography (MEG) Slow-Waves (1-4 Hz) Activity0.2 units on a scaleStandard Deviation 1.4
ControlChange in Abnormal Magnetoencephalography (MEG) Slow-Waves (1-4 Hz) Activity0 units on a scaleStandard Deviation 0
Comparison: The analysis was performed for the voxel-wise delta-band activity from the frontal pole and inferior frontal gyri. Spatial smoothing and logarithm transformation (e-based) were performed. Resting-state MEG activity differences between pre- and post-treatment measures were obtained as difference scores for TES and Sham separately. The null hypothesis was that there was no group difference in the pre- and post-treatment difference scores between TES and Sham groupsp-value: 0.0195% CI: [1.1, 2.2]Wilcoxon (Mann-Whitney)
Primary

Neurobehavioral Symptoms Inventory

The Neurobehavioral Symptoms Inventory (NSI) total score was used to assess the changes of post-concussion symptoms due to TES. Our focus in this analysis was the difference score in NSI total score pre- vs post-treatment measures. The NSI has 22 items and uses a response scale of 0 - 4, with 0 as none and 4 as very severe. Value range: 0 - 88, where the higher scores mean a worse outcome/more severe post-concussive symptoms. For this measure, we focused on the difference score: total score from prior to treatment minus total score from end of treatment. Therefore, the higher the difference score, the more positive change was observed.

Time frame: Baseline through end of treatment, an average of 6 weeks

ArmMeasureValue (MEAN)Dispersion
Transcranial Electrical Stimulation (TES)Neurobehavioral Symptoms Inventory12.3 units on a scaleStandard Deviation 13
TES Sham TreatmentNeurobehavioral Symptoms Inventory12.7 units on a scaleStandard Deviation 10.7
ControlNeurobehavioral Symptoms Inventory0 units on a scaleStandard Deviation 0
Comparison: Differences between pre- and post-treatment measures were obtained as difference scores for TES and Sham separately. The null hypothesis was that there was no group difference in the pre- and post-treatment difference scores between TES and Sham groupsp-value: 0.05Wilcoxon (Mann-Whitney)
Primary

Rivermead Post Concussion Symptom Questionnaire

The Rivermead Post Concussion Symptom Questionnaire (RPQ) total score was used to assess change in post-concussion symptoms due to TES. Our focus in this analysis was the difference score in RPQ total score pre- vs post-treatment measures. The questionnaire has 16 items and uses scale of 0 - 4, with 0 as not experienced at all and 4 as a severe problem. Value range: 0 - 64, where the higher scores mean a worse outcome. For this measure, we focused on the difference score: total score from prior to treatment minus total score from end of treatment. Therefore, the higher the difference score, the more positive change was observed.

Time frame: Baseline through end of treatment, an average of 6 weeks

ArmMeasureValue (MEAN)Dispersion
Transcranial Electrical Stimulation (TES)Rivermead Post Concussion Symptom Questionnaire11.1 units on a scaleStandard Deviation 9.7
TES Sham TreatmentRivermead Post Concussion Symptom Questionnaire10.9 units on a scaleStandard Deviation 11.2
ControlRivermead Post Concussion Symptom Questionnaire0 units on a scaleStandard Deviation 0
Comparison: Differences between pre- and post-treatment measures were obtained as difference scores for TES and Sham separately. The null hypothesis was that there was no group difference in the pre- and post-treatment difference scores between TES and Sham groupsp-value: 0.05Wilcoxon (Mann-Whitney)
Secondary

Barratt Impulsivity Scale

Impulsivity was also measured by Barratt Impulsivity Scale, a self-report questionnaire. This scale contains 30 items, with total scores that range from 30 - 120. The higher the score, the worse the outcome. Analysis was based on the difference score between pre- and post-treatment. The higher the difference score, the more positive change was observed.

Time frame: Up to 6 weeks

ArmMeasureValue (MEAN)Dispersion
Transcranial Electrical Stimulation (TES)Barratt Impulsivity Scale7.6 units on a scaleStandard Deviation 8.1
TES Sham TreatmentBarratt Impulsivity Scale2.4 units on a scaleStandard Deviation 10.8
ControlBarratt Impulsivity Scale0 units on a scaleStandard Deviation 0
Comparison: Differences between pre- and post-treatment measures were obtained as difference scores for TES and Sham separately. The null hypothesis was that there was no group difference in the pre- and post-treatment difference scores between TES and Sham groupsp-value: 0.05Wilcoxon (Mann-Whitney)
Secondary

California Verbal Learning Test-2nd Edition - Free Recall Total Correct T-score

We will use T-scores from verbal learning and retrospective memory (California Verbal Learning Test-2nd Edition). Alternate CVLT forms were used during the post-treatment session. T-score ranges from 5 to 95, where the higher the T-score, the better the outcome. The T-score indicates the number of standard deviations away from the mean, where 50 is the mean with a standard deviation of 10, and is age- and gender-corrected. Analysis was based on the difference score between pre-treatment and post-treatment Free Recall Total Correct T-score. The lower the difference score, the more positive change was observed.

Time frame: Up to 6 weeks

ArmMeasureValue (MEAN)Dispersion
Transcranial Electrical Stimulation (TES)California Verbal Learning Test-2nd Edition - Free Recall Total Correct T-score-6.7 CVLT Free Recall Total Correct t-scoreStandard Deviation 9.8
TES Sham TreatmentCalifornia Verbal Learning Test-2nd Edition - Free Recall Total Correct T-score-2.8 CVLT Free Recall Total Correct t-scoreStandard Deviation 7.4
ControlCalifornia Verbal Learning Test-2nd Edition - Free Recall Total Correct T-score0 CVLT Free Recall Total Correct t-scoreStandard Deviation 0
Comparison: Differences between pre- and post-treatment measures were obtained as difference scores for TES and Sham separately. The null hypothesis was that there was no group difference in the pre- and post-treatment difference scores between TES and Sham groupsp-value: 0.05Wilcoxon (Mann-Whitney)
Secondary

Clinician-Administered PTSD Scale (CAPS-5)

The CAPS-5 is a standard semi-structured interview used to assess PTSD diagnosis and severity. The primary traumatic event is elicited and will be used as the basis of assessing PTSD symptoms. The total symptom severity score is calculated by summing severity scores assessed in this 30-item questionnaire. PTSD diagnostic status will be assessed using the past month version of the CAPS-5A, in which total severity score of 33 or higher indicates full threshold PTSD. The past week version of the CAPS-5 will be given prior to treatment and at follow-up. Severity scores range on a response scale of 0-5, 0=absent, 5=extreme/incapacitating. CAPS-55 summary scores range from 0 to 80, with the higher scores indicating greater severity of PTSD symptoms. For this measure, we focused on the difference score: total score from prior to treatment minus total score from end of treatment. Therefore, the higher the difference score, the more positive change was observed.

Time frame: Up to 6 weeks

ArmMeasureValue (MEAN)Dispersion
Transcranial Electrical Stimulation (TES)Clinician-Administered PTSD Scale (CAPS-5)6.5 units on a scaleStandard Deviation 13.4
TES Sham TreatmentClinician-Administered PTSD Scale (CAPS-5)4.2 units on a scaleStandard Deviation 9.6
ControlClinician-Administered PTSD Scale (CAPS-5)0 units on a scaleStandard Deviation 0
Comparison: Differences between pre- and post-treatment measures were obtained as difference scores for TES and Sham separately. The null hypothesis was that there was no group difference in the pre- and post-treatment difference scores between TES and Sham groupsp-value: 0.05Wilcoxon (Mann-Whitney)
Secondary

Connors Continuous Performance Task II (CPT-II) - Inattention Omissions T-Score

The Connors Continuous Performance Task II (CPT-II) was included as a measure of attention and impulsivity. In this measure, converted T-scores represent the score of the individual relative to the population, who are of the same gender and same age group. A T-score of 50 represents the average for the comparison group. T-score ranges from under 40 (very good performance) to 65+ (markedly atypical). The higher the scores, the worse the performance. This analysis focused on the difference score between the Inattention Omissions T-score pre- and post-treatment. The higher the difference score, the more positive change was observed.

Time frame: Up to 6 weeks

ArmMeasureValue (MEAN)Dispersion
Transcranial Electrical Stimulation (TES)Connors Continuous Performance Task II (CPT-II) - Inattention Omissions T-Score5.71 Inattention Omissions T-scoreStandard Deviation 8.04
TES Sham TreatmentConnors Continuous Performance Task II (CPT-II) - Inattention Omissions T-Score-0.89 Inattention Omissions T-scoreStandard Deviation 10.02
ControlConnors Continuous Performance Task II (CPT-II) - Inattention Omissions T-Score0 Inattention Omissions T-scoreStandard Deviation 0
Comparison: Differences between pre- and post-treatment measures were obtained as difference scores for TES and Sham separately. The null hypothesis was that there was no group difference in the pre- and post-treatment difference scores between TES and Sham groupsp-value: 0.05Wilcoxon (Mann-Whitney)
Secondary

Delis-Kaplan Executive Function System (DKEFS) - Trail Number/Letter Switching Scaled

Throughout the study, we used DKEFS Verbal Fluency, Trail-Making, and Color-Word Interference subtests to assess executive functioning. Analysis was based on the DKEFS Trailmaking Number/Letter Switching scaled score. Scaled scores range from 1-19, where the higher the scaled score, the better the outcome. Analysis was based on the difference score between pre-treatment scaled score and the post-treatment scaled score. The lower the difference score, the more positive change was observed.

Time frame: Up to 6 weeks

ArmMeasureValue (MEAN)Dispersion
Transcranial Electrical Stimulation (TES)Delis-Kaplan Executive Function System (DKEFS) - Trail Number/Letter Switching Scaled-0.77 units on a scaleStandard Deviation 1.13
TES Sham TreatmentDelis-Kaplan Executive Function System (DKEFS) - Trail Number/Letter Switching Scaled-2.08 units on a scaleStandard Deviation 2.03
ControlDelis-Kaplan Executive Function System (DKEFS) - Trail Number/Letter Switching Scaled0 units on a scaleStandard Deviation 0
Comparison: Differences between pre- and post-treatment measures were obtained as difference scores for TES and Sham separately. The null hypothesis was that there was no group difference in the pre- and post-treatment difference scores between TES and Sham groupsp-value: 0.05Wilcoxon (Mann-Whitney)
Secondary

Frontal Systems Behavior Scale

Since frontal lobe areas are more prone to damage, the Frontal Systems Behavior Scale (FrSBe) will measure behavioral dysfunction associated with frontal subcortical impairment. FrSBe is a 46-item rating scale with three subscales: Apathy (14 items), Disinhibition (15 items), and Executive Function (17 items). Items are rated in a 5-point scale, where higher scores mean a worse outcome. The raw scores of these subscales were converted to T-scores, with range of 9 - \>/= 140, where T-scores greater than 65 are considered clinically significant. For this measure, we focused on the difference score of the total T-score prior to treatment minus total score from end of treatment. Therefore, the higher the difference score, the more positive change was observed.

Time frame: Baseline through end of treatment, an average of 6 weeks

Population: Some participants did not complete the FrSBe and/or did not complete all study visits, but analysis was completed on those who finished the FRsBe.

ArmMeasureValue (MEAN)Dispersion
Transcranial Electrical Stimulation (TES)Frontal Systems Behavior Scale9.1 T-scoreStandard Deviation 13.1
TES Sham TreatmentFrontal Systems Behavior Scale3.2 T-scoreStandard Deviation 17.2
ControlFrontal Systems Behavior Scale0 T-scoreStandard Deviation 0
Comparison: Differences between pre- and post-treatment measures were obtained as difference scores for TES and Sham separately. The null hypothesis was that there was no group difference in the pre- and post-treatment difference scores between TES and Sham groupsp-value: 0.05Wilcoxon (Mann-Whitney)
Secondary

Post-Concussion Check List (PCL-5)

PCL-5 is a 20-item self-report measure that assesses the 20 DSM-5 symptoms of PTSD. The PCL-5 uses a response scale of 0 - 4. 0 = Not at all to 4 = Extremely. The total score can range from 0 - 80, with the higher the score corresponding to a higher level of distress to the very stressful experience. The difference between scores post-treatment and pre-treatment will analyzed in addition to the CAPS-5 (1 week version) outcomes. DSM-5 symptom cluster severity scores can be obtained by summing the scores for the items within a given cluster, i.e., cluster B (items 1-5), cluster C (items 6-7), cluster D (items 8-14), and cluster E (items 15-20); these subscale scores may be used in secondary analysis.

Time frame: Up to 6 weeks

ArmMeasureValue (MEAN)Dispersion
Transcranial Electrical Stimulation (TES)Post-Concussion Check List (PCL-5)14.9 units on a scaleStandard Deviation 15.9
TES Sham TreatmentPost-Concussion Check List (PCL-5)12.1 units on a scaleStandard Deviation 24.3
ControlPost-Concussion Check List (PCL-5)0 units on a scaleStandard Deviation 0
Comparison: Differences between pre- and post-treatment measures were obtained as difference scores for TES and Sham separately. The null hypothesis was that there was no group difference in the pre- and post-treatment difference scores between TES and Sham groupsp-value: 0.05Wilcoxon (Mann-Whitney)
Secondary

The McGill Pain Questionnaire (MGPQ)

The McGill Pain Questionnaire (MGPQ) will evaluate the level of current pain, pain changes over time, and strength of pain, since pain is frequently co-morbid with mTBI. Category scores range from 1-2 through 1-6. Minimum score = 0. Maximum score = 78. The higher the pain score, the greater the pain. For this measure, we focused on the difference score: total score from prior to treatment minus total score from end of treatment. Therefore, the higher the difference score, the more positive change was observed.

Time frame: Baseline through end of treatment, an average of 6 weeks

Population: Some participants did not complete the MGPQ and/or did not complete all study visits, therefore, no statistical analysis was completed on this measure.

ArmMeasureValue (MEAN)Dispersion
Transcranial Electrical Stimulation (TES)The McGill Pain Questionnaire (MGPQ)14.8 units on a scaleStandard Deviation 16.9
TES Sham TreatmentThe McGill Pain Questionnaire (MGPQ)-5.1 units on a scaleStandard Deviation 18.1
ControlThe McGill Pain Questionnaire (MGPQ)0 units on a scaleStandard Deviation 0
Comparison: Differences between pre- and post-treatment measures were obtained as difference scores for TES and Sham separately. The null hypothesis was that there was no group difference in the pre- and post-treatment difference scores between TES and Sham groupsp-value: 0.05Wilcoxon (Mann-Whitney)
Secondary

Wechsler Adult Intelligence Scale-4th Edition (WAIS-IV) Processing Speed Index

We will use the sum of scaled scores from the WAIS-IV Symbol Search and Coding subtests to attain the Processing Speed Index. PSI ranged from 50 - 150, where the higher the score, the better the outcome. Analysis was based on the difference score between pre-treatment Processing Speed Index and post-treatment Processing Speed Index. The lower the difference score, the more positive change was observed.

Time frame: Up to 6 weeks

ArmMeasureValue (MEAN)Dispersion
Transcranial Electrical Stimulation (TES)Wechsler Adult Intelligence Scale-4th Edition (WAIS-IV) Processing Speed Index-5.06 units on a scaleStandard Deviation 10.53
TES Sham TreatmentWechsler Adult Intelligence Scale-4th Edition (WAIS-IV) Processing Speed Index-11.48 units on a scaleStandard Deviation 11.21
ControlWechsler Adult Intelligence Scale-4th Edition (WAIS-IV) Processing Speed Index0 units on a scaleStandard Deviation 0
Comparison: Differences between pre- and post-treatment measures were obtained as difference scores for TES and Sham separately. The null hypothesis was that there was no group difference in the pre- and post-treatment difference scores between TES and Sham groupsp-value: 0.05Wilcoxon (Mann-Whitney)

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026