Ignite Creation Date:
2025-12-25 @ 3:26 AM
Ignite Modification Date:
2025-12-26 @ 2:06 AM
Study NCT ID:
NCT04471805
Status:
COMPLETED
Last Update Posted:
2023-05-10
First Post:
2020-07-10
Is NOT Gene Therapy:
False
Has Adverse Events:
True
Brief Title:
4 mA tDCS, Estrogen, and Leg Muscle Fatigability
Sponsor:
Organization:
Raw JSON
{'hasResults': True, 'derivedSection': {'miscInfoModule': {'versionHolder': '2025-12-24', 'submissionTracking': {'firstMcpInfo': {'postDateStruct': {'date': '2023-04-13', 'type': 'ACTUAL'}}}}}, 'resultsSection': {'moreInfoModule': {'pointOfContact': {'email': 'thorsten-rudroff@uiowa.edu', 'phone': '(319)467-0363', 'title': 'Thorsten Rudroff, PhD', 'organization': 'University of Iowa, Department of Health and Human Physiology'}, 'certainAgreement': {'piSponsorEmployee': False, 'restrictiveAgreement': False}}, 'adverseEventsModule': {'timeFrame': 'Completed at each visit, spaced approximately 14 days apart for 2 consecutive months', 'description': 'This study was deemed to be of non-significant risk. This type of brain stimulation has established safety and tolerability data in both human and animal models.', 'eventGroups': [{'id': 'EG000', 'title': 'Eumenorrheic Women', 'description': 'Biological women will have the anode (active electrode) placed over the brain area the controls their dominant leg and the cathode (return electrode) above the eyebrow on the opposite side of the head.\n\nTranscranial direct current stimulation 2 mA: Uses weak electrical current (2 mA intensity) to either increase or decrease brain excitability and improve functional or cognitive outcomes. Stimulation is ramped up to 2 mA over the first 30 seconds and stays at 2 mA for the remainder of the stimulation time.\n\nSham transcranial direct current stimulation 2 mA/4mA: Uses weak electrical current (2 mA or 4 mA intensity) at the beginning and the end of a given stimulation period to control for potential placebo-like effects or participant expectation bias. Stimulation is turned on (2 mA or 4 mA) for the 30 seconds at the beginning and the end of the trial but stays at 0 mA in the intervening time.', 'otherNumAtRisk': 10, 'deathsNumAtRisk': 10, 'otherNumAffected': 0, 'seriousNumAtRisk': 10, 'deathsNumAffected': 0, 'seriousNumAffected': 0}], 'frequencyThreshold': '0'}, 'outcomeMeasuresModule': {'outcomeMeasures': [{'type': 'PRIMARY', 'title': 'Fatigue Index From the Isokinetic Fatigue Test', 'denoms': [{'units': 'Participants', 'counts': [{'value': '10', 'groupId': 'OG000'}]}], 'groups': [{'id': 'OG000', 'title': 'Eumenorrheic Women', 'description': 'Participants will have the anode (active electrode) placed over the brain area that controls their dominant leg and the cathode (return electrode) above the ipsilateral eyebrow. tDCS is administered in the early follicular phase, late follicular phase, and mid-luteal phase of their menstrual cycle.\n\ntDCS: Stimulation is ramped up to 4 mA over the first 30 seconds and stays at 4 mA for the remainder of the simulation time.\n\nSham: Stimulation is turned on (4 mA) for 30 seconds at the beginning and the end of the trial but stays at 0 mA in the intervening time.'}], 'classes': [{'title': 'tDCS High Estrogen', 'categories': [{'measurements': [{'value': '61.7', 'spread': '10.6', 'groupId': 'OG000'}]}]}, {'title': 'Sham High Estrogen', 'categories': [{'measurements': [{'value': '46.7', 'spread': '20.0', 'groupId': 'OG000'}]}]}, {'title': 'tDCS Low Estrogen', 'categories': [{'measurements': [{'value': '57.28', 'spread': '11.57', 'groupId': 'OG000'}]}]}, {'title': 'Sham Low Estrogen', 'categories': [{'measurements': [{'value': '55.90', 'spread': '8.67', 'groupId': 'OG000'}]}]}], 'analyses': [{'pValue': '<0.05', 'groupIds': ['OG000'], 'pValueComment': "Post hoc analyses (paired t-tests and Bonferroni correction) and effect size (Cohen's d) were calculated to clarify significant main effects and interactions.", 'statisticalMethod': 'ANOVA', 'nonInferiorityType': 'SUPERIORITY', 'statisticalComment': "Normality and sphericity evaluated with Shapiro-Wilk test and Mauchly's test. Greenhouse-Geisser corrections used when sphericity was violated."}], 'paramType': 'MEAN', 'timeFrame': 'Completed at each visit, spaced approximately 14 days apart for 2 consecutive months', 'description': 'Perform 40 consecutive flexion and extension repetitions of the knee on the dominant leg. After a 10 minute rest, do the same task on the non-dominant leg.\n\nThe fatigue index was calculated using the greatest torque from the relevant repetitions of the fatigue test as follows: (\\[mean of reps 3 through 7-mean of last five reps\\]/mean of reps 3 through 7) X 100 and is expressed as a percentage of decline in torque production.', 'unitOfMeasure': 'Percent decline', 'dispersionType': 'Standard Deviation', 'reportingStatus': 'POSTED'}, {'type': 'PRIMARY', 'title': 'Muscle Activity During the Strength and Fatigue Tests', 'denoms': [{'units': 'Participants', 'counts': [{'value': '10', 'groupId': 'OG000'}]}], 'groups': [{'id': 'OG000', 'title': 'Eumenorrheic Women', 'description': 'Participants will have the anode (active electrode) placed over the brain area that controls their dominant leg and the cathode (return electrode) above the ipsilateral eyebrow. tDCS is administered in the early follicular phase, late follicular phase, and mid-luteal phase of their menstrual cycle.\n\ntDCS: Stimulation is ramped up to 4 mA over the first 30 seconds and stays at 4 mA for the remainder of the simulation time.\n\nSham: Stimulation is turned on (4 mA) for 30 seconds at the beginning and the end of the trial but stays at 0 mA in the intervening time.'}], 'classes': [{'title': 'tDCS High Estrogen', 'categories': [{'measurements': [{'value': '95.15', 'spread': '26.46', 'groupId': 'OG000'}]}]}, {'title': 'tDCS Low Estrogen', 'categories': [{'measurements': [{'value': '91.83', 'spread': '16.48', 'groupId': 'OG000'}]}]}, {'title': 'Sham High Estrogen', 'categories': [{'measurements': [{'value': '77.53', 'spread': '19.71', 'groupId': 'OG000'}]}]}, {'title': 'Sham Low Estrogen', 'categories': [{'measurements': [{'value': '82.35', 'spread': '21.44', 'groupId': 'OG000'}]}]}], 'analyses': [{'pValue': '<0.05', 'groupIds': ['OG000'], 'pValueComment': "Post hoc analyses (paired t-tests and Bonferroni correction) and effect size (Cohen's d) were calculated to clarify significant main effects and interactions.", 'statisticalMethod': 'ANOVA', 'nonInferiorityType': 'SUPERIORITY', 'statisticalComment': "Normality and sphericity evaluated with Shapiro-Wilk test and Mauchly's test. Greenhouse-Geisser corrections used when sphericity was violated."}], 'paramType': 'MEAN', 'timeFrame': 'Completed at each visit, spaced approximately 14 days apart for 2 consecutive months', 'description': 'Collect electromyographic (EMG; muscle activity) information during the fatigue tests. Muscle activity is measured as electrical signals/voltages.\n\nThe muscle activity of the knee extensors (rectus femoris, vastus medialis, and vastus lateralis) was averaged to represent the cumulative activity of this muscle group. The first two repetitions of the fatigue test were considered adaptation repetitions and were removed. Therefore, the remaining 38 repetitions were used for the average EMG analyses. The subsequent 38 repetitions were also organized into 8 windows. The first seven windows consisted of five consecutive and non-overlapping repetitions (e.g., window 2 = reps 8-12; window 3 = reps 13-17, etc.) while the last (eighth) window was comprised of the final three repetitions.', 'unitOfMeasure': 'Microvolts', 'dispersionType': 'Standard Deviation', 'reportingStatus': 'POSTED'}, {'type': 'SECONDARY', 'title': 'Estrogen Level', 'denoms': [{'units': 'Participants', 'counts': [{'value': '10', 'groupId': 'OG000'}]}], 'groups': [{'id': 'OG000', 'title': 'Eumenorrheic Women', 'description': 'Participants will have the anode (active electrode) placed over the brain area that controls their dominant leg and the cathode (return electrode) above the ipsilateral eyebrow. tDCS is administered in the early follicular phase, late follicular phase, and mid-luteal phase of their menstrual cycle.\n\ntDCS: Stimulation is ramped up to 4 mA over the first 30 seconds and stays at 4 mA for the remainder of the simulation time.\n\nSham: Stimulation is turned on (4 mA) for 30 seconds at the beginning and the end of the trial but stays at 0 mA in the intervening time.'}], 'classes': [{'title': 'tDCS High Estrogen', 'categories': [{'measurements': [{'value': '157.7', 'spread': '101.5', 'groupId': 'OG000'}]}]}, {'title': 'tDCS Low Estrogen', 'categories': [{'measurements': [{'value': '31.9', 'spread': '10.9', 'groupId': 'OG000'}]}]}, {'title': 'Sham High Estrogen', 'categories': [{'measurements': [{'value': '137.2', 'spread': '114.0', 'groupId': 'OG000'}]}]}, {'title': 'Sham Low Estrogen', 'categories': [{'measurements': [{'value': '42.9', 'spread': '25.1', 'groupId': 'OG000'}]}]}], 'paramType': 'MEAN', 'timeFrame': 'Completed at each visit, spaced approximately 14 days apart for 2 consecutive months', 'description': "Staff nurses collected 4.5 mL of blood from the median cubital vein of the left arm (total volume collected per subject = 9 mL) for the estrogen assay. Samples were immediately analyzed for serum estrogen levels after the blood draws by University of Iowa Hospitals and Clinics Pathology technicians using an Electrochemiluminescence Assay (Roche Diagnostics, Basel, Switzerland). The estrogen assay had a lower limit of detection of 5 pg/mL and a coefficient of variation of 8%.\n\nBecause menstrual cycles have great inter- and intrasubject variability, the peak estrogen levels of the subjects were not consistently found in the late-follicular phase, which is a common failing of menstrual cycle phase calendar estimation. Thus, estrogen levels were grouped as high or low according to each individual subject's estrogen serum levels, irrespective of the anticipated/targeted phase.", 'unitOfMeasure': '(pg/mL)', 'dispersionType': 'Standard Deviation', 'reportingStatus': 'POSTED'}]}, 'participantFlowModule': {'groups': [{'id': 'FG000', 'title': 'Eumenorrheic Women', 'description': 'Participants will have the anode (active electrode) placed over the brain area that controls their dominant leg and the cathode (return electrode) above the ipsilateral eyebrow. tDCS is administered in the early follicular phase, late follicular phase, and mid-luteal phase of their menstrual cycle.\n\ntDCS: Stimulation is ramped up to 4 mA over the first 30 seconds and stays at 4 mA for the remainder of the simulation time.\n\nSham: Stimulation is turned on (4 mA) for 30 seconds at the beginning and the end of the trial but stays at 0 mA in the intervening time.'}], 'periods': [{'title': 'Overall Study', 'milestones': [{'type': 'STARTED', 'achievements': [{'groupId': 'FG000', 'numSubjects': '10'}]}, {'type': 'tDCS, Early Follicular Phase', 'achievements': [{'groupId': 'FG000', 'numSubjects': '10'}]}, {'type': 'Sham, Early Follicular Phase', 'achievements': [{'groupId': 'FG000', 'numSubjects': '10'}]}, {'type': 'tDCS, Late Follicular Phase', 'achievements': [{'groupId': 'FG000', 'numSubjects': '10'}]}, {'type': 'Sham, Late Follicular Phase', 'achievements': [{'groupId': 'FG000', 'numSubjects': '10'}]}, {'type': 'tDCS, Mid-Luteal Phase', 'achievements': [{'groupId': 'FG000', 'numSubjects': '10'}]}, {'type': 'Sham, Mid-Luteal Phase', 'achievements': [{'groupId': 'FG000', 'numSubjects': '10'}]}, {'type': 'COMPLETED', 'achievements': [{'groupId': 'FG000', 'numSubjects': '10'}]}, {'type': 'NOT COMPLETED', 'achievements': [{'groupId': 'FG000', 'numSubjects': '0'}]}]}]}, 'baselineCharacteristicsModule': {'denoms': [{'units': 'Participants', 'counts': [{'value': '10', 'groupId': 'BG000'}]}], 'groups': [{'id': 'BG000', 'title': 'Eumenorrheic Women', 'description': 'Biological women will have the anode (active electrode) placed over the brain area the controls their dominant leg and the cathode (return electrode) above the eyebrow on the opposite side of the head.\n\nTranscranial direct current stimulation 2 mA: Uses weak electrical current (2 mA intensity) to either increase or decrease brain excitability and improve functional or cognitive outcomes. Stimulation is ramped up to 2 mA over the first 30 seconds and stays at 2 mA for the remainder of the stimulation time.\n\nSham transcranial direct current stimulation 2 mA/4mA: Uses weak electrical current (2 mA or 4 mA intensity) at the beginning and the end of a given stimulation period to control for potential placebo-like effects or participant expectation bias. Stimulation is turned on (2 mA or 4 mA) for the 30 seconds at the beginning and the end of the trial but stays at 0 mA in the intervening time.'}], 'measures': [{'title': 'Age, Continuous', 'classes': [{'categories': [{'measurements': [{'value': '24.3', 'spread': '5.5', 'groupId': 'BG000'}]}]}], 'paramType': 'MEAN', 'unitOfMeasure': 'years', 'dispersionType': 'STANDARD_DEVIATION'}, {'title': 'Sex: Female, Male', 'classes': [{'categories': [{'title': 'Female', 'measurements': [{'value': '10', 'groupId': 'BG000'}]}, {'title': 'Male', 'measurements': [{'value': '0', 'groupId': 'BG000'}]}]}], 'paramType': 'COUNT_OF_PARTICIPANTS', 'unitOfMeasure': 'Participants'}, {'title': 'Race (NIH/OMB)', 'classes': [{'categories': [{'title': 'American Indian or Alaska Native', 'measurements': [{'value': '0', 'groupId': 'BG000'}]}, {'title': 'Asian', 'measurements': [{'value': '0', 'groupId': 'BG000'}]}, {'title': 'Native Hawaiian or Other Pacific Islander', 'measurements': [{'value': '0', 'groupId': 'BG000'}]}, {'title': 'Black or African American', 'measurements': [{'value': '0', 'groupId': 'BG000'}]}, {'title': 'White', 'measurements': [{'value': '10', 'groupId': 'BG000'}]}, {'title': 'More than one race', 'measurements': [{'value': '0', 'groupId': 'BG000'}]}, {'title': 'Unknown or Not Reported', 'measurements': [{'value': '0', 'groupId': 'BG000'}]}]}], 'paramType': 'COUNT_OF_PARTICIPANTS', 'unitOfMeasure': 'Participants'}, {'title': 'Region of Enrollment', 'classes': [{'title': 'United States', 'categories': [{'measurements': [{'value': '10', 'groupId': 'BG000'}]}]}], 'paramType': 'NUMBER', 'unitOfMeasure': 'participants'}]}}, 'documentSection': {'largeDocumentModule': {'largeDocs': [{'date': '2021-07-08', 'size': 110779, 'label': 'Study Protocol and Statistical Analysis Plan', 'hasIcf': False, 'hasSap': True, 'filename': 'Prot_SAP_001.pdf', 'typeAbbrev': 'Prot_SAP', 'uploadDate': '2023-04-17T08:45', 'hasProtocol': True}]}}, 'protocolSection': {'designModule': {'phases': ['NA'], 'studyType': 'INTERVENTIONAL', 'designInfo': {'allocation': 'NA', 'maskingInfo': {'masking': 'NONE'}, 'primaryPurpose': 'TREATMENT', 'interventionModel': 'SINGLE_GROUP'}, 'enrollmentInfo': {'type': 'ACTUAL', 'count': 10}}, 'statusModule': {'overallStatus': 'COMPLETED', 'startDateStruct': {'date': '2020-10-01', 'type': 'ACTUAL'}, 'expandedAccessInfo': {'hasExpandedAccess': False}, 'statusVerifiedDate': '2023-04', 'completionDateStruct': {'date': '2021-11-01', 'type': 'ACTUAL'}, 'lastUpdateSubmitDate': '2023-04-17', 'studyFirstSubmitDate': '2020-07-10', 'resultsFirstSubmitDate': '2023-03-19', 'studyFirstSubmitQcDate': '2020-07-10', 'lastUpdatePostDateStruct': {'date': '2023-05-10', 'type': 'ACTUAL'}, 'resultsFirstSubmitQcDate': '2023-04-17', 'studyFirstPostDateStruct': {'date': '2020-07-15', 'type': 'ACTUAL'}, 'resultsFirstPostDateStruct': {'date': '2023-05-10', 'type': 'ACTUAL'}, 'primaryCompletionDateStruct': {'date': '2021-11-01', 'type': 'ACTUAL'}}, 'outcomesModule': {'primaryOutcomes': [{'measure': 'Fatigue Index From the Isokinetic Fatigue Test', 'timeFrame': 'Completed at each visit, spaced approximately 14 days apart for 2 consecutive months', 'description': 'Perform 40 consecutive flexion and extension repetitions of the knee on the dominant leg. After a 10 minute rest, do the same task on the non-dominant leg.\n\nThe fatigue index was calculated using the greatest torque from the relevant repetitions of the fatigue test as follows: (\\[mean of reps 3 through 7-mean of last five reps\\]/mean of reps 3 through 7) X 100 and is expressed as a percentage of decline in torque production.'}, {'measure': 'Muscle Activity During the Strength and Fatigue Tests', 'timeFrame': 'Completed at each visit, spaced approximately 14 days apart for 2 consecutive months', 'description': 'Collect electromyographic (EMG; muscle activity) information during the fatigue tests. Muscle activity is measured as electrical signals/voltages.\n\nThe muscle activity of the knee extensors (rectus femoris, vastus medialis, and vastus lateralis) was averaged to represent the cumulative activity of this muscle group. The first two repetitions of the fatigue test were considered adaptation repetitions and were removed. Therefore, the remaining 38 repetitions were used for the average EMG analyses. The subsequent 38 repetitions were also organized into 8 windows. The first seven windows consisted of five consecutive and non-overlapping repetitions (e.g., window 2 = reps 8-12; window 3 = reps 13-17, etc.) while the last (eighth) window was comprised of the final three repetitions.'}], 'secondaryOutcomes': [{'measure': 'Estrogen Level', 'timeFrame': 'Completed at each visit, spaced approximately 14 days apart for 2 consecutive months', 'description': "Staff nurses collected 4.5 mL of blood from the median cubital vein of the left arm (total volume collected per subject = 9 mL) for the estrogen assay. Samples were immediately analyzed for serum estrogen levels after the blood draws by University of Iowa Hospitals and Clinics Pathology technicians using an Electrochemiluminescence Assay (Roche Diagnostics, Basel, Switzerland). The estrogen assay had a lower limit of detection of 5 pg/mL and a coefficient of variation of 8%.\n\nBecause menstrual cycles have great inter- and intrasubject variability, the peak estrogen levels of the subjects were not consistently found in the late-follicular phase, which is a common failing of menstrual cycle phase calendar estimation. Thus, estrogen levels were grouped as high or low according to each individual subject's estrogen serum levels, irrespective of the anticipated/targeted phase."}]}, 'oversightModule': {'isUsExport': False, 'oversightHasDmc': False, 'isFdaRegulatedDrug': False, 'isFdaRegulatedDevice': True}, 'conditionsModule': {'keywords': ['transcranial direct current stimulation', 'muscle fatigue', 'brain stimulation'], 'conditions': ['Healthy']}, 'descriptionModule': {'briefSummary': 'The majority of transcranial direct current stimulation (tDCS) studies have failed to consider sex as a modulating factor. This neglect may partly account for the high inter-subject variability bemoaned by many tDCS investigators (e.g., approximately 50% of participants do not respond to tDCS) and has certainly delayed progress in the field. Therefore, research into how sex influences stimulation-related outcomes is vital to fully understand the underlying mechanisms of tDCS, which has shown great inconsistency.\n\nBecause of the menstrual cycle, the hormonal levels of women fluctuate considerably more than in men. Importantly, these hormonal variations might impact the efficacy of neuromodulatory tools, like tDCS. It is suggested that estrogen, which is high in the second follicular phase, reinforces excitatory mechanisms in the motor cortex. However, because anodal tDCS enhances cortical excitation there is also a possibility of excessive excitability. For instance, anodal tDCS may lead to overexcitation and non-optimal performance when it is applied in the second follicular phase of the menstrual cycle. Currently, there is a lack of knowledge on how the phases of the menstrual cycle affect tDCS performance outcomes in healthy young women because no studies have examined if and how the phases of the menstrual cycle alter tDCS efficacy.\n\nThis study is critical for determining the optimal time to administer anodal tDCS, and the ideal intensity for that administration, to achieve the most beneficial results. Furthermore, this investigation will emphasize the need for future tDCS studies to test women during the same menstrual cycle phase.', 'detailedDescription': 'The majority of transcranial direct current stimulation (tDCS) studies have failed to consider sex as a modulating factor. This neglect may partly account for the high inter-subject variability bemoaned by many tDCS investigators (e.g., approximately 50% of participants do not respond to tDCS) and has certainly delayed progress in the field. Therefore, research into how sex influences stimulation-related outcomes is vital to fully understand the underlying mechanisms of tDCS, which has shown great inconsistency.\n\nBecause of the menstrual cycle, the hormonal levels of women fluctuate considerably more than in men. There are two main phases of the menstrual cycle: 1) the follicular phase, characterized by low levels of estradiol and progesterone (first follicular phase, days 1-7) followed by increased levels of estradiol and low levels of progesterone (second follicular phase, days 7-14); and 2) the luteal phase (days 14-28), characterized by moderate estradiol and high progesterone levels. Importantly, these hormonal variations might impact the efficacy of neuromodulatory tools, like tDCS.\n\nIt is suggested that estrogen, which is high in the second follicular phase, reinforces excitatory mechanisms in the motor cortex. Thus, it appears that higher levels of estradiol increase cortical excitability. However, because anodal tDCS enhances cortical excitation there is also a possibility of excessive excitability. For instance, anodal tDCS may lead to overexcitation and nonoptimal performance when it is applied in the second follicular phase of the menstrual cycle. Currently, there is a lack of knowledge on how the phases of the menstrual cycle affect tDCS performance outcomes in healthy young women because no studies have examined if and how the phases of the menstrual cycle alter tDCS efficacy.\n\nThis research will be significant because the changing hormone levels during the different phases of menstruation in women is an especially important factor for minimizing response variability from tDCS. Thus, this study is critical for determining the optimal time to administer anodal tDCS, and the ideal intensity for that administration, to achieve the most beneficial results. Furthermore, this investigation will emphasize the need for future tDCS studies to test women during the same menstrual cycle phase.'}, 'eligibilityModule': {'sex': 'FEMALE', 'stdAges': ['ADULT'], 'maximumAge': '35 Years', 'minimumAge': '18 Years', 'healthyVolunteers': True, 'eligibilityCriteria': 'Inclusion Criteria:\n\n1. Has a regular menstrual cycle\n2. Young adult (18-35 years)\n3. Right-side dominant\n4. At least 30 min of moderate-intensity, physical activity on at least 3 days of the week for at least the last 3 months\n5. Without chronic neurological, psychiatric, or medical conditions\n6. Not taking any psychoactive medications.\n\nExclusion Criteria:\n\n1. Pregnant\n2. Known holes or fissures in the skull\n3. Metallic objects or implanted devices in the skull (e.g., metal plate)\n4. Women on hormonal contraceptives/supplements.'}, 'identificationModule': {'nctId': 'NCT04471805', 'briefTitle': '4 mA tDCS, Estrogen, and Leg Muscle Fatigability', 'organization': {'class': 'OTHER', 'fullName': 'University of Iowa'}, 'officialTitle': 'Estrogen Levels and Leg Muscle Fatigability in Eumenorrheic Young Women After 4 mA Transcranial Direct Current Stimulation', 'orgStudyIdInfo': {'id': '202005124'}}, 'armsInterventionsModule': {'armGroups': [{'type': 'EXPERIMENTAL', 'label': 'Eumenorrheic Women', 'description': 'Participants will have the anode (active electrode) placed over the brain area that controls their dominant leg and the cathode (return electrode) above the ipsilateral eyebrow. tDCS is administered in the early follicular phase, late follicular phase, and mid-luteal phase of their menstrual cycle.\n\ntDCS: Stimulation is ramped up to 4 mA over the first 30 seconds and stays at 4 mA for the remainder of the simulation time.\n\nSham: Stimulation is turned on (4 mA) for 30 seconds at the beginning and the end of the trial but stays at 0 mA in the intervening time.', 'interventionNames': ['Device: Sham transcranial direct current stimulation 4 mA', 'Device: Transcranial direct current stimulation 4 mA']}], 'interventions': [{'name': 'Sham transcranial direct current stimulation 4 mA', 'type': 'DEVICE', 'otherNames': ['Sham tDCS 2 mA'], 'description': 'Uses weak electrical current (4 mA intensity) at the beginning and the end of a given stimulation period to control for potential placebo-like effects or participant expectation bias.', 'armGroupLabels': ['Eumenorrheic Women']}, {'name': 'Transcranial direct current stimulation 4 mA', 'type': 'DEVICE', 'otherNames': ['tDCS 4 mA'], 'description': 'Uses weak electrical current (4 mA intensity) to either increase or decrease brain excitability and improve functional or cognitive outcomes.', 'armGroupLabels': ['Eumenorrheic Women']}]}, 'contactsLocationsModule': {'locations': [{'zip': '52242', 'city': 'Iowa City', 'state': 'Iowa', 'country': 'United States', 'facility': 'University of Iowa', 'geoPoint': {'lat': 41.66113, 'lon': -91.53017}}], 'overallOfficials': [{'name': 'Thorsten Rudroff, PhD', 'role': 'PRINCIPAL_INVESTIGATOR', 'affiliation': 'Health and Human Physiology'}]}, 'sponsorCollaboratorsModule': {'leadSponsor': {'name': 'University of Iowa', 'class': 'OTHER'}, 'responsibleParty': {'type': 'PRINCIPAL_INVESTIGATOR', 'investigatorTitle': 'Assistant Professor', 'investigatorFullName': 'Thorsten Rudroff', 'investigatorAffiliation': 'University of Iowa'}}}}