Speech
Conditions
Keywords
speech motor control, vocal learning
Brief summary
The purpose of this research study is to understand how the brain processes and controls speech in healthy people. The investigators are doing this research because it will help identify the mechanisms that allow people to perceive their own speech errors and to learn new speech sounds, which may be applied to people who have communication disorders. 15 participants will be enrolled into this part of the study and can expect to be on study for 4 visits of 2-4 hours each.
Detailed description
The overall study (Establishing the clinical utility of sensorimotor adaptation for speech rehabilitation) aims to understand how cognitive, perceptual, and motor processes are integrated in the control of speech movements. The investigators study how this complex skill is performed in healthy speakers to understand how this system functions, how this skill relates to the perception of speech, and what role different parts of the brain play in this process. Different studies look at how speech motor control is executed, maintained, and changed. Overall, the study will recruit 329 participants over the course of 5 years. Participants can expect to be on study for up to 3 weeks. The entire study is composed of 8 experiments and 6 interventions. The present record represents the experiments involving transcranial magnetic stimulation (TMS), i.e. Experiment 7: Using TMS to alter somatosensory acuity. This paradigm uses theta-burst transcranial magnetic stimulation (tbTMS) to modulate the excitability of sensory cortices to examine the effect on sensory acuity and sensorimotor adaptation. Participants will complete three total sessions targeting primary somatosensory cortex (S1): one using intermittent theta-burst stimulation (iTBS), one using continuous theta-burst stimulation (cTBS), and one with sham stimulation. The effect of the stimulation on auditory acuity will be measured through a tactile discrimination task in which participants report the relative amplitude and/or timing of vibrating probes pressed lightly into the tongue using a custom device (a version of the Corticalmetrics Brain Gauge adapted to study the orofacial system).
Interventions
DEVICETMS
This paradigm uses theta-burst transcranial magnetic stimulation (tbTMS) to modulate the excitability of sensory cortices to examine the effect on sensory acuity and sensorimotor adaptation. Participants will complete three total sessions targeting primary somatosensory cortex (S1): one using intermittent theta-burst stimulation (iTBS), one using continuous theta-burst stimulation (cTBS), and one with sham stimulation.
BEHAVIORALsomatosensory acuity measurement
Somatosensory acuity will be measured through a tactile discrimination task using the corticalmetrics Brain Gauge. Participants lightly press their tongue onto two vibrating probes and report which one vibrated first or with greater amplitude.
Sponsors
National Institute on Deafness and Other Communication Disorders (NIDCD)
University of Wisconsin, Madison
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 70 Years
Healthy volunteers
Yes
Inclusion criteria
(Control): * English-speaking adults * normal hearing and speech * no history of stroke or neurological conditions
Exclusion criteria
* Native language other than English * Any neurological disorders other than the disorder of interest * Any history of hearing disorders * Uncorrected vision problems that prevent participants from seeing visually-presented stimuli * Significant cognitive impairments that prevent participants from carrying out the task or from giving informed consent * Vulnerable populations (minors and prisoners) * Additional exclusionary criteria for TMS: * Implanted paramagnetic materials (metal clips, plates, pacemakers, etc.) * Increased risk in the event of a seizure * Serious heart disease * Increased intracranial pressure * Pregnancy * History of seizures * Family history of epilepsy * Epileptogenic medications * Chronic or transient disruption of sleep (including jet lag) * History of fainting * Chronic or transient increase in stressful experiences * Use of illegal drugs
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Somatosensory Acuity: Spatial Amplitude Discrimination Threshold (SDT) | up to 1 hour | The investigators will measure thresholds in spatial amplitude discrimination (SDT). These thresholds represent the smallest difference that participants can detect in the amplitude of vibration on the tongue. Vibratory stimulation is delivered by the corticalmetrics Brain Gauge device, which has two probes, one on the left and one on the right side of the tongue. Participants will complete three total sessions targeting primary somatosensory cortex (S1): one using intermittent theta-burst stimulation (iTBS), one using continuous theta-burst stimulation (cTBS), and one with sham stimulation. Tactile acuity measured in this way is used as a proxy for full somatosensation, given the difficulty in measuring proprioception in the oral system. Tactile acuity has been suggested to be important for speech production, as tactile contact is maintained parasagittally during vowel production and tactile deprivation leads to imprecise speech movements. |
| Somatosensory Acuity: Temporal Discrimination Threshold (TDT) | up to 1 hour | The investigators will measure thresholds in temporal discrimination (SDT). These thresholds represent the smallest difference that participants can detect in the timing of vibrations on the tongue. Vibratory stimulation is delivered by the corticalmetrics Brain Gauge device, which has two probes, one on the left and one on the right side of the tongue. Participants will complete three total sessions targeting primary somatosensory cortex (S1): one using intermittent theta-burst stimulation (iTBS), one using continuous theta-burst stimulation (cTBS), and one with sham stimulation. Tactile acuity measured in this way is used as a proxy for full somatosensation, given the difficulty in measuring proprioception in the oral system. Tactile acuity has been suggested to be important for speech production, as tactile contact is maintained parasagittally during vowel production and tactile deprivation leads to imprecise speech movements. |
Countries
United States
Participant flow
Recruitment details
15 people provided data for this study from November 2022 to May 2023
Participants by arm
| Arm | Count |
|---|---|
| Healthy Adult Speakers healthy adult participants across the lifespan in three groups:18-35, 36-55, and 56+
TMS: This paradigm uses theta-burst transcranial magnetic stimulation (tbTMS) to modulate the excitability of sensory cortices to examine the effect on sensory acuity and sensorimotor adaptation. Participants will complete three total sessions targeting primary somatosensory cortex (S1): one using intermittent theta-burst stimulation (iTBS), one using continuous theta-burst stimulation (cTBS), and one with sham stimulation.
somatosensory acuity measurement: Somatosensory acuity will be measured through a tactile discrimination task using the corticalmetrics Brain Gauge. Participants lightly press their tongue onto two vibrating probes and report which one vibrated first or with greater amplitude. | 15 |
| Total | 15 |
Baseline characteristics
| Characteristic | Healthy Adult Speakers |
|---|---|
| Age, Continuous | 25 years |
| Ethnicity (NIH/OMB) Hispanic or Latino | 1 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 14 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants |
| Race (NIH/OMB) Asian | 8 Participants |
| Race (NIH/OMB) Black or African American | 0 Participants |
| Race (NIH/OMB) More than one race | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants |
| Race (NIH/OMB) White | 7 Participants |
| Region of Enrollment United States | 15 participants |
| Sex: Female, Male Female | 8 Participants |
| Sex: Female, Male Male | 7 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | 0 / 15 |
| other Total, other adverse events | 0 / 15 |
| serious Total, serious adverse events | 0 / 15 |
Outcome results
Primary
Somatosensory Acuity: Spatial Amplitude Discrimination Threshold (SDT)
The investigators will measure thresholds in spatial amplitude discrimination (SDT). These thresholds represent the smallest difference that participants can detect in the amplitude of vibration on the tongue. Vibratory stimulation is delivered by the corticalmetrics Brain Gauge device, which has two probes, one on the left and one on the right side of the tongue. Participants will complete three total sessions targeting primary somatosensory cortex (S1): one using intermittent theta-burst stimulation (iTBS), one using continuous theta-burst stimulation (cTBS), and one with sham stimulation. Tactile acuity measured in this way is used as a proxy for full somatosensation, given the difficulty in measuring proprioception in the oral system. Tactile acuity has been suggested to be important for speech production, as tactile contact is maintained parasagittally during vowel production and tactile deprivation leads to imprecise speech movements.
Time frame: up to 1 hour
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Healthy Adult Speakers | Somatosensory Acuity: Spatial Amplitude Discrimination Threshold (SDT) | SDT (cTBS) | 20.08 change in threshold (µm) | Standard Error 7.37 |
| Healthy Adult Speakers | Somatosensory Acuity: Spatial Amplitude Discrimination Threshold (SDT) | SDT (iTBS) | -8.07 change in threshold (µm) | Standard Error 3.74 |
| Healthy Adult Speakers | Somatosensory Acuity: Spatial Amplitude Discrimination Threshold (SDT) | SDT (sham) | 5.39 change in threshold (µm) | Standard Error 5.59 |
| Healthy Adult Speakers | Somatosensory Acuity: Spatial Amplitude Discrimination Threshold (SDT) | SDT (control) | -2.81 change in threshold (µm) | Standard Error 5.24 |
Primary
Somatosensory Acuity: Temporal Discrimination Threshold (TDT)
The investigators will measure thresholds in temporal discrimination (SDT). These thresholds represent the smallest difference that participants can detect in the timing of vibrations on the tongue. Vibratory stimulation is delivered by the corticalmetrics Brain Gauge device, which has two probes, one on the left and one on the right side of the tongue. Participants will complete three total sessions targeting primary somatosensory cortex (S1): one using intermittent theta-burst stimulation (iTBS), one using continuous theta-burst stimulation (cTBS), and one with sham stimulation. Tactile acuity measured in this way is used as a proxy for full somatosensation, given the difficulty in measuring proprioception in the oral system. Tactile acuity has been suggested to be important for speech production, as tactile contact is maintained parasagittally during vowel production and tactile deprivation leads to imprecise speech movements.
Time frame: up to 1 hour
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Healthy Adult Speakers | Somatosensory Acuity: Temporal Discrimination Threshold (TDT) | TDT (cTBS) | 0.41 change in threshold (ms) | Standard Error 6.44 |
| Healthy Adult Speakers | Somatosensory Acuity: Temporal Discrimination Threshold (TDT) | TDT (iTBS) | 5.80 change in threshold (ms) | Standard Error 3.59 |
| Healthy Adult Speakers | Somatosensory Acuity: Temporal Discrimination Threshold (TDT) | TDT (sham) | 4.54 change in threshold (ms) | Standard Error 6.6 |
| Healthy Adult Speakers | Somatosensory Acuity: Temporal Discrimination Threshold (TDT) | TDT (control) | -2.97 change in threshold (ms) | Standard Error 6.25 |