MRI Study of High Definition Transcranial Electrical Stimulation in Chronic Tinnitus (MRI HDtES-T)

This is an investigator-initiated MRI study of High Definition (HD) transcranial electrical stimulation (tES) in adults with chronic subjective tinnitus. HDtES is a mild, noninvasive form of brain stimulation using small electrodes to target a small part of the brain/cortex. Primary outcomes are changes in brain function and connectivity measured with MRI before and after a single 20-minute session of HDtES. Secondary outcomes are changes in tinnitus symptoms after 20-minutes of HDtES on 5 consecutive days.

Inclusion criteria

• Ages between 18 and 75
• Race/ethnicity: all races and ethnic groups
• Sex/Gender: all
• Capacity to provide informed consent
• Subjective tinnitus symptoms confirmed by patient self report meeting the following criteria:

• Present for at least one year prior to start of study
• Present (can be heard when consciously attended to) >50% of awake time
• Intrudes (is heard even when attempting to ignore/mask) >10% of awake time
• Has discussed tinnitus symptoms with clinician (i.e., physician, audiologist) to confirm low/no likelihood of physical or neurological origin of tinnitus symptoms (e.g., acoustic neuroma, Meniere's Disease, etc.), confirmed by patient self-report
• Stable standard or no pharmacological treatment regimen for tinnitus with no change in treatment 6 weeks prior to study start

Exclusion criteria

• Ages below 18 (neurobiology is quite different in children vs. adults)
• Ages above 75 (cortical excitability changes with age)
• Tinnitus symptoms with known medial origin, including:

• Meniere's disease
• Pulsatile tinnitus
• Acoustic neuroma
• Spontaneous optoacoustic emissions
• Any other known medical origin
• Severe mood disorder (major depression or anxiety)
• Diagnosis of any medical condition potentially affecting brain function, including:

• neuropsychiatric or mental disorders (bipolar, post-traumatic stress disorder, etc.)
• severe mood disorders (major depression or anxiety)
• psychotic states or disorders
• developmental disorders
• neurological disorders, including mild cognitive impairment
• significant head injury
• significant history of alcohol/substance abuse or dependence
• active chronic pain condition (>1 year duration)
• other major medical conditions (e.g., cancer, stroke).
• MRI contraindications:

• metal or other implants that are not MR-safe
• claustrophobia
• pregnancy or suspected pregnancy
• tDCS contraindications*:

• skin conditions or injuries on the scalp
• hair extensions, wigs, braids, etc. that cannot be removed prior to the study
• metal implants or pacemakers (also contraindicated for MRI)
• Non-English speakers (due to written consent and questionnaires administered)
• Significant history of alcohol/substance abuse or dependence within last 12 months
• Neurostimulation or neuromodulation treatment longer than 20 minutes within the past 3 months
• Current medication use potentially affecting brain function, including decongestants, antihistamines, benzodiazepines or other anticonvulsants, or anti-psychotics.