Trial Outcomes & Findings for Flexible Representation of Speech (NCT NCT05209386)
NCT ID: NCT05209386
Last Updated: 2025-09-08
Results Overview
Neural activity will be measured via simultaneous EEG-sEEG monitoring in the supratemporal plane as indicated by high-gamma band activity in the electrical signal. Neural activity will be measured as participants listen to acoustic stimuli with gradually manipulated acoustic dimensions, fundamental frequency (F0) and voice onset time (VOT). The data reported here is the number of temporal lobe channels demonstrating significant encoding of change in acoustic dimension (F0 as VOT is held constant).
COMPLETED
NA
48 participants
During sEEG-EEG recording sessions, up to 3 hours total
2025-09-08
Participant Flow
Participants were recruited from PI Abel's clinical population of patients undergoing invasive monitoring (sEEG) for drug-resistant epilepsy at Children's Hospital of Pittsburgh between May 2022-May 2025.
As there is only a single experimental group in this study, all enrolled patients were assigned to Arm 1 (Patient Participants).
Participant milestones
| Measure |
Patient Participants
This single-group study will recruit patients through the PI's clinical practice who are undergoing invasive neurophysiological monitoring (sEEG) with clinically necessary placement of electrodes in the supratemporal plane.
All participants will complete the same behavioral response paradigms.
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|---|---|
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Overall Study
STARTED
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48
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Overall Study
COMPLETED
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16
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Overall Study
NOT COMPLETED
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32
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Reasons for withdrawal
| Measure |
Patient Participants
This single-group study will recruit patients through the PI's clinical practice who are undergoing invasive neurophysiological monitoring (sEEG) with clinically necessary placement of electrodes in the supratemporal plane.
All participants will complete the same behavioral response paradigms.
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|---|---|
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Overall Study
Withdrawal by Subject
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8
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Overall Study
Period of sEEG implant insufficient to collect complete behavioral task
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24
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Baseline Characteristics
Flexible Representation of Speech
Baseline characteristics by cohort
| Measure |
Patient Participants
n=16 Participants
This single-group study will recruit patients through the PI's clinical practice who are undergoing invasive neurophysiological monitoring (sEEG) with clinically necessary placement of electrodes in the supratemporal plane.
All participants will complete the same behavioral response paradigms.
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|---|---|
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Age, Continuous
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17.62 years
STANDARD_DEVIATION 3.10 • n=5 Participants
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Sex: Female, Male
Female
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6 Participants
n=5 Participants
|
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Sex: Female, Male
Male
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10 Participants
n=5 Participants
|
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Ethnicity (NIH/OMB)
Hispanic or Latino
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0 Participants
n=5 Participants
|
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Ethnicity (NIH/OMB)
Not Hispanic or Latino
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14 Participants
n=5 Participants
|
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Ethnicity (NIH/OMB)
Unknown or Not Reported
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2 Participants
n=5 Participants
|
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Race (NIH/OMB)
American Indian or Alaska Native
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0 Participants
n=5 Participants
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Race (NIH/OMB)
Asian
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0 Participants
n=5 Participants
|
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Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
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0 Participants
n=5 Participants
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Race (NIH/OMB)
Black or African American
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0 Participants
n=5 Participants
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Race (NIH/OMB)
White
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16 Participants
n=5 Participants
|
|
Race (NIH/OMB)
More than one race
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0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=5 Participants
|
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Phoneme Categorization
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81.5 percent of stimuli classified as /p/
STANDARD_DEVIATION 4.1 • n=5 Participants
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PRIMARY outcome
Timeframe: During sEEG-EEG recording sessions, up to 3 hours totalPopulation: Neural data from 3 participants was contaminated by noise and was thus excluded from analysis.
Neural activity will be measured via simultaneous EEG-sEEG monitoring in the supratemporal plane as indicated by high-gamma band activity in the electrical signal. Neural activity will be measured as participants listen to acoustic stimuli with gradually manipulated acoustic dimensions, fundamental frequency (F0) and voice onset time (VOT). The data reported here is the number of temporal lobe channels demonstrating significant encoding of change in acoustic dimension (F0 as VOT is held constant).
Outcome measures
| Measure |
Patient Participants
n=618 sEEG Channels
This single-group study will recruit patients through the PI's clinical practice who are undergoing invasive neurophysiological monitoring (sEEG) with clinically necessary placement of electrodes in the supratemporal plane.
All participants will complete the same behavioral response paradigms.
Dimension-Based Statistical Learning: Each participant will complete self-paced blocks of stimuli that will first establish a baseline for neural activity and behavioral responses with clear speech, and will then record responses for experimentally manipulated blocks to introduce a Canonical-Reverse block to model an "accent." Auditory stimuli will be adjusted to a comfortable level for each participant as determined by a calibration process completed by the participant. Each block involves listening to sound via earphones and making a categorical decision between initial consonants (/b/ or /p/) by tapping a button to indicate the word heard by the participant.
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|---|---|
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Supratemporal Neural Response to Change in Acoustic-Phonetic Dimensions
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17 sEEG Channels
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PRIMARY outcome
Timeframe: During sEEG-EEG recording sessions, up to 3 hours totalPopulation: 2 participants were excluded because they performed \<50% on catch trials (0 and 40 ms VOTs); 1 participant was excluded because of a data quality issue
Behavioral responses in the form of a category judgment will be obtained as participants listen to acoustic stimuli in with gradually varying fundamental frequency (F0) and voice onset time (VOT). Participants will provide a behavioral response by indicating the phoneme perceived at the beginning of stimulus words (/b/ or /p/). Specifically, the outcome is reported as percent of stimuli classified as /p/ over varying F0 with VOT held constant.
Outcome measures
| Measure |
Patient Participants
n=13 Participants
This single-group study will recruit patients through the PI's clinical practice who are undergoing invasive neurophysiological monitoring (sEEG) with clinically necessary placement of electrodes in the supratemporal plane.
All participants will complete the same behavioral response paradigms.
Dimension-Based Statistical Learning: Each participant will complete self-paced blocks of stimuli that will first establish a baseline for neural activity and behavioral responses with clear speech, and will then record responses for experimentally manipulated blocks to introduce a Canonical-Reverse block to model an "accent." Auditory stimuli will be adjusted to a comfortable level for each participant as determined by a calibration process completed by the participant. Each block involves listening to sound via earphones and making a categorical decision between initial consonants (/b/ or /p/) by tapping a button to indicate the word heard by the participant.
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|---|---|
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Behavioral Impact of Change in Acoustic-Phonetic Dimensions
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37.4 percent of stimuli classified as /p/
Standard Error 6.4
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PRIMARY outcome
Timeframe: During sEEG-EEG recording sessions, up to 3 hours totalPopulation: Neural data from 3 participants were contaminated by noise and therefore excluded from analysis. Channels included in this analysis were only those that demonstrated significant encoding of acoustic features (F0).
Neural activity was measured via sEEG monitoring as indicated by high-gamma band activity in the electrical signal. Neural activity will be measured as participants listen to acoustic stimuli in accented speech. The un-transformed voltage represents the difference in electric potential between a specific electrode contact and the reference electrode contact; since we use a common average reference, that means it's the difference between a specific electrode contact and the mean voltage across all electrodes. We then z-score to characterize shifts from baseline activity (where z = 0) at a specific electrode, which is believed to measure changes in voltage due largely to post-synaptic currents. This is a mathematical transformation rather than a published scale or standardized assessment. More extreme z-scores (+ or -) indicate a greater change from baseline local neural activity; in other words, stimuli evoked greater activity in this region.
Outcome measures
| Measure |
Patient Participants
n=17 sEEG Channels
This single-group study will recruit patients through the PI's clinical practice who are undergoing invasive neurophysiological monitoring (sEEG) with clinically necessary placement of electrodes in the supratemporal plane.
All participants will complete the same behavioral response paradigms.
Dimension-Based Statistical Learning: Each participant will complete self-paced blocks of stimuli that will first establish a baseline for neural activity and behavioral responses with clear speech, and will then record responses for experimentally manipulated blocks to introduce a Canonical-Reverse block to model an "accent." Auditory stimuli will be adjusted to a comfortable level for each participant as determined by a calibration process completed by the participant. Each block involves listening to sound via earphones and making a categorical decision between initial consonants (/b/ or /p/) by tapping a button to indicate the word heard by the participant.
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|---|---|
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Supratemporal Neural Response to Change in Listening Context
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0.55 Difference in z-scored voltage
Standard Error 0.12
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PRIMARY outcome
Timeframe: During sEEG-EEG recording sessions, up to 3 hours totalPopulation: 2 participants were excluded because they performed \<50% on catch trials (0 and 40 ms VOTs); 1 participant was excluded because of a data quality issue
Behavioral responses in the form of a category judgment will be obtained as participants listen to acoustic stimuli in a varied listening context: accented speech. Participants will provide a behavioral response by indicating the phoneme perceived at the beginning of stimulus words (/b/ or /p/). Specifically, the outcome is reported as the mean % of stimuli classified as /p/ with varying VOT and F0 relationships.
Outcome measures
| Measure |
Patient Participants
n=13 Participants
This single-group study will recruit patients through the PI's clinical practice who are undergoing invasive neurophysiological monitoring (sEEG) with clinically necessary placement of electrodes in the supratemporal plane.
All participants will complete the same behavioral response paradigms.
Dimension-Based Statistical Learning: Each participant will complete self-paced blocks of stimuli that will first establish a baseline for neural activity and behavioral responses with clear speech, and will then record responses for experimentally manipulated blocks to introduce a Canonical-Reverse block to model an "accent." Auditory stimuli will be adjusted to a comfortable level for each participant as determined by a calibration process completed by the participant. Each block involves listening to sound via earphones and making a categorical decision between initial consonants (/b/ or /p/) by tapping a button to indicate the word heard by the participant.
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|---|---|
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Behavioral Impact of Change in Listening Context
Low F0/Ambiguous VOT
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54.9 percent of stimuli classified as /p/
Standard Error 6.3
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Behavioral Impact of Change in Listening Context
High F0/Ambiguous VOT
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30.3 percent of stimuli classified as /p/
Standard Error 6.0
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SECONDARY outcome
Timeframe: During sEEG-EEG recording sessions, up to 3 hours totalPopulation: Neural data from 3 participants was contaminated by noise and was thus excluded from analysis.
Neural activity will be measured via simultaneous EEG-sEEG monitoring in the supratemporal plane as indicated by high-gamma band activity in the electrical signal. Neural activity will be measured as participants listen to acoustic stimuli with gradually manipulated acoustic dimensions, fundamental frequency (F0) and voice onset time (VOT). The data reported here is the number of temporal lobe channels demonstrating significant encoding of change in acoustic dimension (F0 as VOT is held constant).
Outcome measures
| Measure |
Patient Participants
n=2088 sEEG Channels
This single-group study will recruit patients through the PI's clinical practice who are undergoing invasive neurophysiological monitoring (sEEG) with clinically necessary placement of electrodes in the supratemporal plane.
All participants will complete the same behavioral response paradigms.
Dimension-Based Statistical Learning: Each participant will complete self-paced blocks of stimuli that will first establish a baseline for neural activity and behavioral responses with clear speech, and will then record responses for experimentally manipulated blocks to introduce a Canonical-Reverse block to model an "accent." Auditory stimuli will be adjusted to a comfortable level for each participant as determined by a calibration process completed by the participant. Each block involves listening to sound via earphones and making a categorical decision between initial consonants (/b/ or /p/) by tapping a button to indicate the word heard by the participant.
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|---|---|
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Neural Response of Non-Regions of Interest to Change in Acoustic-Dimension
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4 sEEG Channels
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SECONDARY outcome
Timeframe: During sEEG-EEG recording sessions, up to 3 hours totalPopulation: Channels included in this secondary analysis (n = 4 from n = 3 patients) were only those that demonstrated significant encoding of acoustic features (F0).
Neural activity was measured via sEEG monitoring as indicated by high-gamma band activity in the electrical signal. Neural activity will be measured as participants listen to acoustic stimuli in accented speech. The un-transformed voltage represents the difference in electric potential between a specific electrode contact and the reference electrode contact; since we use a common average reference, that means it's the difference between a specific electrode contact and the mean voltage across all electrodes. We then z-score to characterize shifts from baseline activity (where z = 0) at a specific electrode, which is believed to measure changes in voltage due largely to post-synaptic currents. This is a mathematical transformation rather than a published scale or standardized assessment. More extreme z-scores (+ or -) indicate a greater change from baseline local neural activity; in other words, stimuli evoked greater activity in this region.
Outcome measures
| Measure |
Patient Participants
n=4 sEEG Channels
This single-group study will recruit patients through the PI's clinical practice who are undergoing invasive neurophysiological monitoring (sEEG) with clinically necessary placement of electrodes in the supratemporal plane.
All participants will complete the same behavioral response paradigms.
Dimension-Based Statistical Learning: Each participant will complete self-paced blocks of stimuli that will first establish a baseline for neural activity and behavioral responses with clear speech, and will then record responses for experimentally manipulated blocks to introduce a Canonical-Reverse block to model an "accent." Auditory stimuli will be adjusted to a comfortable level for each participant as determined by a calibration process completed by the participant. Each block involves listening to sound via earphones and making a categorical decision between initial consonants (/b/ or /p/) by tapping a button to indicate the word heard by the participant.
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|---|---|
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Neural Response of Non-Regions of Interest to Change in Listening Context
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-0.11 Difference in z-scored voltage
Standard Error 0.064
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Adverse Events
Patient Participants
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place