RecruitingNot ApplicableNCT07079839

A Neurosensory Account of Anxiety and Stress (Study 2)

Threat-related Sensory Cortical (SC) Disinhibition and SPA Pathology in Posttraumatic Stress Disorder (PTSD) (Aim 3; Expts. 2&3)

Sponsor

The University of Texas Health Science Center, Houston

Enrollment

160 participants

Start Date

Jul 3, 2025

Study Type

INTERVENTIONAL

Conditions

Posttraumatic Stress Disorder (PTSD)Threat-related Sensory Cortical (SC) Disinhibition

Summary

This study will take a basic neuroscience approach to investigate pathological mechanisms underlying PTSD. Additionally, the study aims to identify how Transcranial Alternating Current Stimulation (tACS) brain stimulation can modulate and correct neural networks and related emotions of anxious arousal and hypervigilance, with the goal of assessing tACS brain stimulation technology as a novel intervention for symptoms of anxiety.

Eligibility

Min Age: 18 YearsMax Age: 50 Years

Inclusion Criteria7

Right-handed
With normal or corrected-to-normal vision and normal olfaction
Between the ages of 18 and 50 years
Meeting the tACS screening criteria (see List I below; e.g., lack of a serious head injury or loss of consciousness)
Patients: Diagnosis of PTSD
Patients: If taking psychotropic medications, medication stability in the past 2 months
If having mild substance use disorder (for patients) or occasional substance use, abstention from use 48 hours before the experiment.

Exclusion Criteria11

A history of diagnosis for a major medical illness (e.g., cancer, metabolic syndrome, cardiovascular disease, inflammatory disorders) or a neurological disorder (e.g., seizure, stroke, Parkinson's disease).
Patients: Concurrent Axis I diagnosis (depression, anxiety, and mild substance use disorder are allowed given their high comorbidity with PTSD).
Healthy controls: A history of diagnosis for a Diagnostic and Statistical Manual of Mental Disorders (DSM)-5 Axis I disorder or current use of psychoactive medications.
Severe psychiatric instability or severe situational life crises, including evidence of being actively suicidal or homicidal, or any behavior that poses an immediate danger to self or others.
History of head trauma with unconsciousness (\> 5 minutes)
Report that they regularly drink 3 or more alcoholic beverages a day.
Report that they are unable to abstain from substance use (including alcohol, nicotine, cannabis, amphetamines, narcotics, solvents, cocaine, hallucinogens, tranquilizers, barbiturates, etc.) or sleep medication for 48 hours before being scanned.
Are on calcium channel blockers (e.g., verapamil, nifedipine) or alpha-blockers (e.g., prazosin, terazosin) and are unable to stop these medications for a 48-hour period prior to scanning (to exclude the impact of these medications on the interpretation of fMRI/EEG).
Failed Urine Drug Screening Test: A rapid urine screening test that utilizes monoclonal antibodies to detect elevated levels of specific drugs (including alcohol, amphetamines, benzodiazepines, barbiturates, cocaine, marijuana, opiates, etc.) in urine (iCup)
Pregnancy based on urine test. The safety of magnetic resonance (MR) systems has not been established for fetuses
Having electrically, magnetically, or mechanically activated implants (e.g., cardiac pacemakers), because the electromagnetic fields produced by the MR system may interfere with the operation of these devices.

Interventions

DEVICETranscranial Alternating Current Stimulation (tACS)

A weak electrical current will be passed through the scalp over targeted cortical regions via a transcranial electrical stimulation system (Soterix Medical, Inc), for a span of 10 to 40 minutes at a time. Participants will receive a 2 milliamp (mA) sinusoidal current oscillating at individual participants' baseline peak alpha frequencies (PAF; 7-13 Hz), which will be determined by a 3-min resting state EEG recording during the setup. Current intensities will be modified to address individual participants' subjective reports of discomfort, with a maximum intensity of 2 mA. Stimulation electrodes will be placed within an EEG cap fitted over the participant's head.

DEVICESham for Transcranial Alternating Current Stimulation (tACS)

Stimulation electrodes will be placed on the scalp, but no current will be passed. Stimulation electrodes will be placed within an EEG cap fitted over the participant's head.

DEVICETranscranial Random Noise stimulation (tRNS)

A weak electrical currents will be passed through the scalp over targeted cortical regions via a transcranial electrical stimulation system (Soterix Medical, Inc), for a span of 10 to 40 minutes at a time. Participants will receive a 2 mA sinusoidal current oscillating at random frequency (1-200 Hz). Current intensities will be modified to address individual participants' subjective reports of discomfort, with a maximum intensity of 2 mA. Stimulation electrodes will be placed within an EEG cap fitted over the participant's head.