At-home Transcranial Alternating Current Stimulation During Multitasking

• Sponsor: University of California, San Francisco (Other)
• Overall Status: Completed
• CT.gov ID: NCT04231825
• Collaborator: (none)
• Enrollment: 47
• Location: 1
• Arms: 2
• Actual Duration (Months): 11
• Patients Per Site Per Month: 4.3

Study Details

Study Description

Brief Summary

The goal is to replicate in-lab results from transcranial alternating current stimulation (tACS) with at-home tACS.

Condition or Disease	Intervention/Treatment	Phase
Multitasking Behavior	Device: Transcranial alternating current stimulation	N/A

Detailed Description

Participants will be assessed in-lab on multitasking and sustained attention abilities. Participants will be sent home with a tACS device to be used at-home for five days while engaged in a multitasking paradigm that is different from the multitasking outcome measure used pre/post tACS. After the at-home stimulation is complete, participants return to UCSF for a final in-lab assessment of multitasking and sustained attention ability.

Study Design

• Study Type: Interventional
• Actual Enrollment: 47 participants
• Allocation: Randomized
• Intervention Model: Parallel Assignment
• Masking: Triple (Participant, Investigator, Outcomes Assessor)
• Primary Purpose: Basic Science
• Official Title: At-home Transcranial Alternating Current Stimulation During Multitasking
• Actual Study Start Date: Oct 15, 2019
• Actual Primary Completion Date: Aug 15, 2020
• Actual Study Completion Date: Sep 15, 2020

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Verum Stimulation This group will receive 6-Hz tACS	Device: Transcranial alternating current stimulation; Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.
Active Comparator: Frequency Control This group will receive 1-Hz tACS	Device: Transcranial alternating current stimulation; Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.

Outcome Measures

Primary Outcome Measures

1. Multitasking Performance Cost (Neuroracer Performance Change From Baseline) [Pre-tACS and post-tACS (1 week later)]

   Assessment of multitasking ability using change from baseline scores in d' cost (metric of discriminability). Discrimination performance (d') was measured for each participant by comparing hit (correct responses to target signs) rates and false alarm (responses to non-targets) rates and calculated as d' = Z (hits) - Z (false alarms). d' cost was then calculated as the ratio of d' during single task target discrimination task to multitask target discrimination, expressed as percentage cost.

2. Single Task Performance Change [Pre-tACS and post-tACS (1 week later)]

   Discrimination performance (d') was measured during single task performance for each participant by comparing hit (correct responses to target signs) rates and false alarm (responses to non-targets) rates and calculated as d' = Z (hits) - Z (false alarms). Performance data was collected during the single task condition.

3. Multitask Performance Change [Pre-tACS and post-tACS (1 week later)]

   Discrimination performance (d') was measured while multitasking for each participant by comparing hit (correct responses to target signs) rates and false alarm (responses to non-targets) rates and calculated as d' = Z (hits) - Z (false alarms). Performance data was collected during the multitask condition.

Secondary Outcome Measures

1. Continuous Performance Test RT Change (Test of Visual Attention / Sustained Attention) [Pre-tACS and post-tACS (1 week later)]

   Assessment of sustained attention ability using response time (in ms) during the continuous performance test

2. Continuous Performance Test RTV Change (Test of Visual Attention / Sustained Attention) [Pre-tACS and post-tACS (1 week later)]

   Assessment of sustained attention ability using response time variability (standard deviation of response times in ms) during the continuous performance test

Eligibility Criteria

Criteria

• Ages Eligible for Study: 18 Years to 35 Years
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Inclusion Criteria:

• English speaking

• Grade 12 or more education

• Normal or corrected to normal vision and hearing

• Ability to complete cognitive tasks

• Ability to cooperate and comply with all study procedures

• Ability to tolerate tACS

Exclusion Criteria:

• Neurological or psychiatric disorders

• Family history of epilepsy

• History of seizures

• Prior head trauma

• Pregnant

• Implanted electronic devices (e.g., pacemaker)

• IQ < 80

• Taking psychotropic medication

• Taking anti-depressants or anti-anxiety medication

• Substance abuse

• Color blind

• Glaucoma

• Macular degeneration

• Amblyopia

• Strabismus

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Sandler Neurosciences Center	San Francisco	California	United States	94158

Sponsors and Collaborators

• University of California, San Francisco

Investigators

• Principal Investigator: Theodore Zanto, Ph.D., University of California, San Francisco

Study Documents (Full-Text)

• Study Protocol and Statistical Analysis Plan - Aug 11, 2021
• Informed Consent Form - Sep 3, 2019

More Information

Publications

None provided.

• Responsible Party: University of California, San Francisco
• ClinicalTrials.gov Identifier: NCT04231825
• Other Study ID Numbers: 18-26268-1
• First Posted: Jan 18, 2020
• Last Update Posted: Mar 21, 2022
• Last Verified: Mar 1, 2022

• Individual Participant Data (IPD) Sharing Statement: Yes
• Plan to Share IPD: Yes
• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: Yes
• Product Manufactured in and Exported from the U.S.: No

Study Results

Participant Flow

Arm/Group Title	Verum Stimulation	Frequency Control
Arm/Group Description	This group will receive 6-Hz tACS Transcranial alternating current stimulation: Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.	This group will receive 1-Hz tACS Transcranial alternating current stimulation: Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.
Period Title: Overall Study
STARTED	23	24
COMPLETED	20	20
NOT COMPLETED	3	4

Baseline Characteristics

Arm/Group Title	Verum Stimulation	Frequency Control	Total
Arm/Group Description	This group will receive 6-Hz tACS Transcranial alternating current stimulation: Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.	This group will receive 1-Hz tACS Transcranial alternating current stimulation: Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.	Total of all reporting groups
Overall Participants	23	24	47
Age (Count of Participants)
<=18 years	1 4.3%	1 4.2%	2 4.3%
Between 18 and 65 years	19 82.6%	19 79.2%	38 80.9%
>=65 years	0 0%	0 0%	0 0%
Age (years) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [years]	25.8 (4.6)	24.6 (4.2)	25.2 (4.4)
Sex: Female, Male (Count of Participants)
Female	12 52.2%	13 54.2%	25 53.2%
Male	8 34.8%	7 29.2%	15 31.9%
Race (NIH/OMB) (Count of Participants)
American Indian or Alaska Native	0 0%	0 0%	0 0%
Asian	3 13%	4 16.7%	7 14.9%
Native Hawaiian or Other Pacific Islander	0 0%	0 0%	0 0%
Black or African American	1 4.3%	2 8.3%	3 6.4%
White	15 65.2%	12 50%	27 57.4%
More than one race	1 4.3%	2 8.3%	3 6.4%
Unknown or Not Reported	0 0%	0 0%	0 0%
Region of Enrollment (Count of Participants)
United States	20 87%	20 83.3%	40 85.1%
Single Task Performance (d') [Mean (Standard Deviation) ]
Mean (Standard Deviation) [d']	1.73 (0.63)	2.01 (0.63)	1.87 (0.63)
Multitask performance (d') [Mean (Standard Deviation) ]
Mean (Standard Deviation) [d']	1.03 (0.63)	1.20 (0.58)	1.12 (0.60)
Multitasking Cost Performance (Percent change) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [Percent change]	45.8 (0.40)	40.5 (0.22)	43.2 (0.31)
Continuous Performance Task RT (milliseconds) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [milliseconds]	322 (43)	322 (34)	322 (39)
Continuous Performance Task RTV (milliseconds) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [milliseconds]	76 (7)	65 (5)	71 (6)

Outcome Measures

1. Primary Outcome

Title	Multitasking Performance Cost (Neuroracer Performance Change From Baseline)
Description	Assessment of multitasking ability using change from baseline scores in d' cost (metric of discriminability). Discrimination performance (d') was measured for each participant by comparing hit (correct responses to target signs) rates and false alarm (responses to non-targets) rates and calculated as d' = Z (hits) - Z (false alarms). d' cost was then calculated as the ratio of d' during single task target discrimination task to multitask target discrimination, expressed as percentage cost.
Time Frame	Pre-tACS and post-tACS (1 week later)

Outcome Measure Data

Analysis Population Description

Only data from participants who completed the full protocol were analyzed

Arm/Group Title	Verum Stimulation	Frequency Control
Arm/Group Description	This group will receive 6-Hz tACS Transcranial alternating current stimulation: Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.	This group will receive 1-Hz tACS Transcranial alternating current stimulation: Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.
Measure Participants	20	20
Mean (Standard Deviation) [percentage change of d']	45.3 (0.31)	37.9 (0.27)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Verum Stimulation, Frequency Control
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.55
	Comments
	Method	ANCOVA
	Comments

2. Secondary Outcome

Title	Continuous Performance Test RT Change (Test of Visual Attention / Sustained Attention)
Description	Assessment of sustained attention ability using response time (in ms) during the continuous performance test
Time Frame	Pre-tACS and post-tACS (1 week later)

Outcome Measure Data

Analysis Population Description

Only data from participants who completed the full protocol were analyzed

Arm/Group Title	Verum Stimulation	Frequency Control
Arm/Group Description	This group will receive 6-Hz tACS Transcranial alternating current stimulation: Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.	This group will receive 1-Hz tACS Transcranial alternating current stimulation: Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.
Measure Participants	20	20
Mean (Standard Deviation) [milliseconds]	300 (42)	303 (31)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Verum Stimulation, Frequency Control
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.51
	Comments
	Method	ANCOVA
	Comments

3. Secondary Outcome

Title	Continuous Performance Test RTV Change (Test of Visual Attention / Sustained Attention)
Description	Assessment of sustained attention ability using response time variability (standard deviation of response times in ms) during the continuous performance test
Time Frame	Pre-tACS and post-tACS (1 week later)

Outcome Measure Data

Analysis Population Description

Only data from participants who completed the full protocol were analyzed

Arm/Group Title	Verum Stimulation	Frequency Control
Arm/Group Description	This group will receive 6-Hz tACS Transcranial alternating current stimulation: Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.	This group will receive 1-Hz tACS Transcranial alternating current stimulation: Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.
Measure Participants	20	20
Mean (Standard Deviation) [milliseconds]	58 (26)	56 (21)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Verum Stimulation, Frequency Control
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.80
	Comments
	Method	ANCOVA
	Comments

4. Primary Outcome

Title	Single Task Performance Change
Description	Discrimination performance (d') was measured during single task performance for each participant by comparing hit (correct responses to target signs) rates and false alarm (responses to non-targets) rates and calculated as d' = Z (hits) - Z (false alarms). Performance data was collected during the single task condition.
Time Frame	Pre-tACS and post-tACS (1 week later)

Outcome Measure Data

Analysis Population Description

Only data from participants who completed the full protocol were analyzed

Arm/Group Title	Verum Stimulation	Frequency Control
Arm/Group Description	This group will receive 6-Hz tACS Transcranial alternating current stimulation: Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.	This group will receive 1-Hz tACS Transcranial alternating current stimulation: Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.
Measure Participants	20	20
Mean (Standard Deviation) [d']	1.99 (0.94)	2.70 (1.07)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Verum Stimulation, Frequency Control
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.02
	Comments
	Method	ANCOVA
	Comments

5. Primary Outcome

Title	Multitask Performance Change
Description	Discrimination performance (d') was measured while multitasking for each participant by comparing hit (correct responses to target signs) rates and false alarm (responses to non-targets) rates and calculated as d' = Z (hits) - Z (false alarms). Performance data was collected during the multitask condition.
Time Frame	Pre-tACS and post-tACS (1 week later)

Outcome Measure Data

Analysis Population Description

Only data from participants who completed the full protocol were analyzed

Arm/Group Title	Verum Stimulation	Frequency Control
Arm/Group Description	This group will receive 6-Hz tACS Transcranial alternating current stimulation: Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.	This group will receive 1-Hz tACS Transcranial alternating current stimulation: Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.
Measure Participants	20	20
Mean (Standard Deviation) [d']	1.17 (0.76)	1.79 (0.89)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Verum Stimulation, Frequency Control
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.03
	Comments
	Method	ANCOVA
	Comments

Adverse Events

Time Frame	10 months
Arm/Group Title	Verum Stimulation		Frequency Control
Arm/Group Description	This group will receive 6-Hz tACS Transcranial alternating current stimulation: Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.		This group will receive 1-Hz tACS Transcranial alternating current stimulation: Transcranial alternating current stimulation across the prefrontal cortex using electrodes F3 and F4.
All Cause Mortality
	Verum Stimulation		Frequency Control
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/23 (0%)		0/24 (0%)
Serious Adverse Events
	Verum Stimulation		Frequency Control
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/23 (0%)		0/24 (0%)
Other (Not Including Serious) Adverse Events
	Verum Stimulation		Frequency Control
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	1/23 (4.3%)		2/24 (8.3%)
Product Issues
Other (Not Including Serious) Adverse Event	1/23 (4.3%)	1	2/24 (8.3%)	2

Limitations/Caveats

[Not Specified]

More Information

Certain Agreements

All Principal Investigators ARE employed by the organization sponsoring the study.

There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.