This preliminary study is designed to evaluate mechanisms by which excitatory dorsolateral prefrontal cortex (dlPFC) repetitive transcranial magnetic stimulation (rTMS) (vs. sham) and pharmacological stress (vs. placebo) alter behavior in non-treatment seeking individuals with opioid use disorder (OUD). Specific Aims are to (1) Evaluate how stress impacts domains of behavior including (1a) executive function and (1b) opioid-seeking behavior; and (2) Determine whether rTMS stimulation attenuates (2a) executive dysfunction, (2b) stress-reactivity, and (2c) opioid-seeking in individuals with OUD not receiving treatment.
This study will use a double-blind, 10Hz left dlPFC rTMS (vs. sham) and pharmacological stressor (\[yohimbine + hydrocortisone\] vs. placebo) within-subject, randomized crossover design. Each participant will complete 4 sessions (stressor vs. placebo, crossed with rTMS vs. sham), each separated by at least 1 week. Participants will complete these 4 (2x2 within subject) test conditions in randomized order: sham rTMS/placebo stress, sham rTMS/active stress, active rTMS/ placebo stress, and active rTMS/active stress. The PI will perform randomization using a Latin Square and will assign participants to conditions and prepare medication (stressor or placebo) for each participant's sessions. The PI will keep others blinded and will not be involved in study assessments.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
BASIC_SCIENCE
Masking
DOUBLE
Enrollment
20
Yohimbine (54mg bulk powder inside capsule) administered in combination with Hydrocortisone (20mg tablet inside capsule)
10Hz rTMS over the left dlPFC
lactose (inside capsule)
inactive stimulation over the left dlPFC
Tolan Park Medical Building
Detroit, Michigan, United States
Color-Word Stroop Task
measures cognitive control in response to opioid-related words.
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Digit Span Task
measures verbal working memory. Participants are asked to repeat strings of numbers of increasing length, both forward and backward.
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Wisconsin Card Sorting Task
measures ability to shift set and assesses cognitive flexibility.
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Emotion Regulation Task
subjects rate the unpleasantness and arousal of different emotional pictures
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Positive and Negative Affect Schedule
subjects rate their positive and negative affect
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
State-Trait Anxiety Inventory
subjects rate their level state anxiety
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Monetary Incentive Delay Task
Participants respond to a visual target that follows 2 different cues: incentive or non-incentive. No reward or punishment occurs on non-incentive trials. On incentive trials, participants must respond within a fixed amount of time. In the reward condition, responses within that time result in receiving the incentive , else nothing. In the punishment condition, the participant will lose money if they do not respond within the time limit
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Delay Discounting Task
Participants perform a brief (\<1min) hypothetical version of the traditional monetary task with a 5-trial adjusting delay previously validated to rapidly assess discount rate
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Drug/Money Choice Task
participants choose hypothetically between a constant amount of their preferred opioid ($10 unit dose) or money ($2)
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Systolic blood pressure
millimeters mercury (mmHg)
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Diastolic blood pressure
millimeters mercury (mmHg)
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Heart rate
beats per minute
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Saliva cortisol level
measure of the activity of the HPA axis
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Saliva alpha-amylase level
indirect measure of adrenergic stimulation
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Serum prolactin level
indirect measure of dopamine stimulation
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Serum brain derived neurotrophic factor (BDNF) level
indirect measure of brain derived neurotrophic factor activation
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Relative electroencephalogram (EEG) gamma power
Prefrontal gamma (25-100 Hz) EEG power, relative to slow-wave EEG power, is a stress biomarker
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Opioid craving
Desire for Drug Questionnaire total score; higher scores indicate greater craving
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Opioid agonist symptoms
Opiate-32 questionnaire agonist symptom total score; higher scores indicate greater opioid symptom severity
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
Opioid withdrawal symptoms
Opiate-32 questionnaire withdrawal symptom total score; higher scores indicate greater withdrawal severity
Time frame: change from pre- to post-intervention in each of 4 sessions (through study completion, about 1 month total)
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