Trial Outcomes & Findings for Effects of Sensory Flicker and Electrical Flicker Stimulation (NCT NCT04188834)
NCT ID: NCT04188834
Last Updated: 2024-03-26
Results Overview
The power spectral density of the LFP will be measured across stimulus frequencies and modalities of sensory flicker stimuli in visual areas, auditory areas, hippocampus, and prefrontal cortex. To evaluate the effects of sensory flicker on brain activity in various brain regions, researchers compared the average increase in oscillatory neural activity of given recorded brain regions during sensory stimulation, among the total number of recording locations that showed a significant response to sensory stimulation compared to baseline. In participants in whom a condition was repeated across multiple experimental sessions. If a location showed a significant response in multiple sessions, the data point that showed the highest level of response was kept. The average fold-change increase in oscillatory activity, 25th and 75th percentiles, within a region of interest is reported.
Recruitment status
COMPLETED
Study phase
NA
Target enrollment
23 participants
Primary outcome timeframe
During experiment session (up to 2 hours) during hospital admission (up to 2 weeks)
Results posted on
2024-03-26
Participant Flow
Participants were recruited from Emory University Hospital in Atlanta, Georgia, USA. Participant enrollment began January 10, 2020, and all follow up was complete by November 22, 2022.
Participants only had the Sensory Flicker Stimulation. In the initial IRB protocol submission, the research team intended to potentially do electrical flicker experiments as further exploration of their project but ended up opting not to pursue this avenue.
Participant milestones
| Measure |
Sensory Flicker Stimulation
Participants will be exposed for about 10 to 60 minutes at a time, to a sequence of sensory flicker trials each lasting a few seconds to 5 minutes, while their eyes are open or closed. Each trial may include the following modalities and frequencies of flicker:
* Modalities: auditory only, visual only, or audiovisual combined.
* Frequencies: random, or anywhere from 3Hz to 200Hz.
Additionally, subjects may be exposed to individual pulses of light and/or sound, i.e. around or less than 1 pulse /second, for up to 20 minutes at a time.
Customized version of DAVID device: A customized version of the DAVID device will be used to expose participants to sensory flicker. The device consists of opaque glasses containing LEDs to present flickering light, as well as earbuds or headphones to present flickering sound.
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|---|---|
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Overall Study
STARTED
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23
|
|
Overall Study
COMPLETED
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19
|
|
Overall Study
NOT COMPLETED
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4
|
Reasons for withdrawal
| Measure |
Sensory Flicker Stimulation
Participants will be exposed for about 10 to 60 minutes at a time, to a sequence of sensory flicker trials each lasting a few seconds to 5 minutes, while their eyes are open or closed. Each trial may include the following modalities and frequencies of flicker:
* Modalities: auditory only, visual only, or audiovisual combined.
* Frequencies: random, or anywhere from 3Hz to 200Hz.
Additionally, subjects may be exposed to individual pulses of light and/or sound, i.e. around or less than 1 pulse /second, for up to 20 minutes at a time.
Customized version of DAVID device: A customized version of the DAVID device will be used to expose participants to sensory flicker. The device consists of opaque glasses containing LEDs to present flickering light, as well as earbuds or headphones to present flickering sound.
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|---|---|
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Overall Study
Participants did not complete enough proportion of experiment(s) to be included in analysis
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4
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Baseline Characteristics
Effects of Sensory Flicker and Electrical Flicker Stimulation
Baseline characteristics by cohort
| Measure |
Sensory Flicker Stimulation
n=23 Participants
Participants will be exposed for about 10 to 60 minutes at a time, to a sequence of sensory flicker trials each lasting a few seconds to 5 minutes, while their eyes are open or closed. Each trial may include the following modalities and frequencies of flicker:
* Modalities: auditory only, visual only, or audiovisual combined.
* Frequencies: random, or anywhere from 3Hz to 200Hz.
Additionally, subjects may be exposed to individual pulses of light and/or sound, i.e. around or less than 1 pulse /second, for up to 20 minutes at a time.
Customized version of DAVID device: A customized version of the DAVID device will be used to expose participants to sensory flicker. The device consists of opaque glasses containing LEDs to present flickering light, as well as earbuds or headphones to present flickering sound.
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|---|---|
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Age, Categorical
<=18 years
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0 Participants
n=5 Participants
|
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Age, Categorical
Between 18 and 65 years
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23 Participants
n=5 Participants
|
|
Age, Categorical
>=65 years
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0 Participants
n=5 Participants
|
|
Age, Continuous
|
33.7 years
STANDARD_DEVIATION 11.7 • n=5 Participants
|
|
Sex: Female, Male
Female
|
14 Participants
n=5 Participants
|
|
Sex: Female, Male
Male
|
9 Participants
n=5 Participants
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
1 Participants
n=5 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
22 Participants
n=5 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Asian
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Black or African American
|
6 Participants
n=5 Participants
|
|
Race (NIH/OMB)
White
|
16 Participants
n=5 Participants
|
|
Race (NIH/OMB)
More than one race
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
1 Participants
n=5 Participants
|
|
Region of Enrollment
United States
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23 participants
n=5 Participants
|
PRIMARY outcome
Timeframe: During experiment session (up to 2 hours) during hospital admission (up to 2 weeks)Population: Participants who completed study procedures and had valid data points for each frequency and region are included.
The power spectral density of the LFP will be measured across stimulus frequencies and modalities of sensory flicker stimuli in visual areas, auditory areas, hippocampus, and prefrontal cortex. To evaluate the effects of sensory flicker on brain activity in various brain regions, researchers compared the average increase in oscillatory neural activity of given recorded brain regions during sensory stimulation, among the total number of recording locations that showed a significant response to sensory stimulation compared to baseline. In participants in whom a condition was repeated across multiple experimental sessions. If a location showed a significant response in multiple sessions, the data point that showed the highest level of response was kept. The average fold-change increase in oscillatory activity, 25th and 75th percentiles, within a region of interest is reported.
Outcome measures
| Measure |
Sensory Flicker Stimulation
n=19 Participants
Participants will be exposed for about 10 to 60 minutes at a time, to a sequence of sensory flicker trials each lasting a few seconds to 5 minutes, while their eyes are open or closed. Each trial may include the following modalities and frequencies of flicker:
* Modalities: auditory only, visual only, or audiovisual combined.
* Frequencies: random, or anywhere from 3Hz to 200Hz.
Additionally, subjects may be exposed to individual pulses of light and/or sound, i.e. around or less than 1 pulse /second, for up to 20 minutes at a time.
Customized version of DAVID device: A customized version of the DAVID device will be used to expose participants to sensory flicker. The device consists of opaque glasses containing LEDs to present flickering light, as well as earbuds or headphones to present flickering sound.
|
|---|---|
|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
Visual Region to 5.5Hz-V
|
4.6 Fold-change in power
Interval 1.2 to 11.2
|
|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
Visual Region to 40Hz-V
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4 Fold-change in power
Interval 1.3 to 15.8
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Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
Visual Region to 80Hz-V
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1.1 Fold-change in power
Interval 0.6 to 3.5
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Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
Visual Region to 5.5Hz-A
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0.5 Fold-change in power
Interval 0.4 to 0.7
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Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
Visual Region to 40Hz-A
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0.4 Fold-change in power
Interval 0.3 to 0.8
|
|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
Visual Region to 80Hz-A
|
0.6 Fold-change in power
Interval 0.4 to 0.7
|
|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
Auditory Region to 5.5Hz-V
|
0.9 Fold-change in power
Interval 0.6 to 2.0
|
|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
Auditory Region to 40Hz-V
|
0.7 Fold-change in power
Interval 0.5 to 3.5
|
|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
Auditory Region to 80Hz-V
|
0.7 Fold-change in power
Interval 0.4 to 3.6
|
|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
Auditory Region to 5.5Hz-A
|
0.7 Fold-change in power
Interval 0.5 to 1.2
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|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
Auditory Region to 40Hz-A
|
1.6 Fold-change in power
Interval 0.6 to 4.6
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|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
Auditory Region to 80Hz-A
|
1 Fold-change in power
Interval 0.5 to 3.4
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Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
Medial temporal lobe (MTL) Region to 5.5Hz-V
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0.6 Fold-change in power
Interval 0.5 to 1.4
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Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
MTL Region to 40Hz-V
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0.8 Fold-change in power
Interval 0.5 to 1.4
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|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
MTL Region to 80Hz-V
|
0.6 Fold-change in power
Interval 0.4 to 0.9
|
|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
MTL Region to 5.5Hz-A
|
0.7 Fold-change in power
Interval 0.5 to 1.6
|
|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
MTL Region to 40Hz-A
|
0.6 Fold-change in power
Interval 0.4 to 1.1
|
|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
MTL Region to 80Hz-A
|
0.5 Fold-change in power
Interval 0.4 to 0.6
|
|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
PFC Region to 5.5Hz-V
|
0.5 Fold-change in power
Interval 0.4 to 0.9
|
|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
PFC Region to 40Hz-V
|
0.5 Fold-change in power
Interval 0.4 to 1.0
|
|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
PFC Region to 80Hz-V
|
0.5 Fold-change in power
Interval 0.4 to 1.2
|
|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
PFC Region to 5.5Hz-A
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0.5 Fold-change in power
Interval 0.4 to 0.6
|
|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
PFC Region to 40Hz-A
|
0.5 Fold-change in power
Interval 0.4 to 0.5
|
|
Fold-change in Oscillatory Activity (Power Spectral Density) in Response to Exposure to Sensory Flicker: Comparing Mean Power Spectral Density at the Frequency of Flicker Being Presented Between Flicker and Baseline Periods
PFC Region to 80Hz-A
|
0.4 Fold-change in power
Interval 0.3 to 0.6
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SECONDARY outcome
Timeframe: During experiment session (up to 2 hours) during hospital admission (up to 2 weeks)Population: Participants who completed study procedures and had valid data points for each frequency and region are included.
The change of of the sensory flicker effect will be evaluated by the comparison of the whole-brain rate of IEDs between sensory flicker stimulation and baseline (no stimulation).
Outcome measures
| Measure |
Sensory Flicker Stimulation
n=19 Participants
Participants will be exposed for about 10 to 60 minutes at a time, to a sequence of sensory flicker trials each lasting a few seconds to 5 minutes, while their eyes are open or closed. Each trial may include the following modalities and frequencies of flicker:
* Modalities: auditory only, visual only, or audiovisual combined.
* Frequencies: random, or anywhere from 3Hz to 200Hz.
Additionally, subjects may be exposed to individual pulses of light and/or sound, i.e. around or less than 1 pulse /second, for up to 20 minutes at a time.
Customized version of DAVID device: A customized version of the DAVID device will be used to expose participants to sensory flicker. The device consists of opaque glasses containing LEDs to present flickering light, as well as earbuds or headphones to present flickering sound.
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|---|---|
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Effect of Sensory Flicker on the Rate of Interictal Epileptiform Discharges (IEDs) Which Represent Pathological Activity Often Observed in Epilepsy
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-3.0 Percent change
Interval -4.5 to -1.6
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Adverse Events
Sensory Flicker Stimulation
Serious events: 0 serious events
Other events: 16 other events
Deaths: 0 deaths
Serious adverse events
Adverse event data not reported
Other adverse events
| Measure |
Sensory Flicker Stimulation
n=23 participants at risk
Participants will be exposed for about 10 to 60 minutes at a time, to a sequence of sensory flicker trials each lasting a few seconds to 5 minutes, while their eyes are open or closed. Each trial may include the following modalities and frequencies of flicker:
* Modalities: auditory only, visual only, or audiovisual combined.
* Frequencies: random, or anywhere from 3Hz to 200Hz.
Additionally, subjects may be exposed to individual pulses of light and/or sound, i.e. around or less than 1 pulse /second, for up to 20 minutes at a time.
Customized version of DAVID device: A customized version of the DAVID device will be used to expose participants to sensory flicker. The device consists of opaque glasses containing LEDs to present flickering light, as well as earbuds or headphones to present flickering sound.
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|---|---|
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Nervous system disorders
Headache or discomfort
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34.8%
8/23 • Number of events 10 • Adverse events that occurred during the experimental sessions (up to 2h) and were conducted during the patient's hospital stay are reported. Participant's hospital stay duration was strictly determined by the clinical team based on clinical needs and typically lasted about 2 weeks.
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General disorders
Fatigue
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34.8%
8/23 • Number of events 10 • Adverse events that occurred during the experimental sessions (up to 2h) and were conducted during the patient's hospital stay are reported. Participant's hospital stay duration was strictly determined by the clinical team based on clinical needs and typically lasted about 2 weeks.
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General disorders
Miscellaneous
|
34.8%
8/23 • Number of events 8 • Adverse events that occurred during the experimental sessions (up to 2h) and were conducted during the patient's hospital stay are reported. Participant's hospital stay duration was strictly determined by the clinical team based on clinical needs and typically lasted about 2 weeks.
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Nervous system disorders
Seizure likely unrelated to experiment
|
13.0%
3/23 • Number of events 3 • Adverse events that occurred during the experimental sessions (up to 2h) and were conducted during the patient's hospital stay are reported. Participant's hospital stay duration was strictly determined by the clinical team based on clinical needs and typically lasted about 2 weeks.
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Additional Information
Dr. Annabelle Singer
Georgia Institute of Technology Atlanta
Phone: 404.385.4936
Email: [email protected]
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place