Brain Mechanism and Intervention of Executive-control Dysfunction Among Substance Dependents

Brain Mechanism and Intervention of Executive-control Dysfunction Caused by Impaired Prefrontal-ventral Striatum Synchronization Among Substance Dependents

The investigators assume that tACS could improve amphetamine and alcohol dependent patients' executive-control function by adjusting the synchronization patterns and enhancing the functional connectivity of the prefrontal-ventral striatum pathway. A random controlled trial will be used to test the effect of θ-tACS treatment. Three months follow-up assessment will be conducted to test the changing of executive-control function and its mechanism.

Substance abuse has become a major social and public health problem in China, especially for amphetamine abuse and alcohol abuse. Executive-control dysfunction is the main symptom for substance dependents. Previous studies have demonstrated the relationship between cognitive dysfunction and prefrontal-ventral striatum pathway. Studies have shown that abnormal phase synchronization and phase-amplitude coupling (PAC) induced the impairment of cognitive, and tACS could improve executive-control function by adjusting the abnormal synchronization. But it has not been verified among MA or alcohol patients. The investigators assume that tACS could improve MA and alcohol dependent patients' executive-control function by adjusting the synchronization patterns and enhancing the functional connectivity of the prefrontal-ventral striatum pathway. A random controlled trial will be used to test the effect of θ-tACS treatment. Three months follow-up assessment will be conducted to test the changing of executive-control function and its mechanism. This study will provide a practical and theoretical basis for developing a novel treatment for substance dependents.

Inclusion Criteria:

• Aged 18-60, male or female, with 9 or more years of education, and able to complete questionnaire evaluation and behavioral tests
• Meet DSM-5 diagnostic criteria for amphetamine-type substance addiction or alcohol addiction
• Have used amphetamine or alcohol for at least one year (at least once a week)
• Normal vision and hearing, or within the normal range after correction
• Agree to cooperate in the follow-up evaluation
• No metal implantation in the head, no history of nerve problems or head injury, and no skin sensitivity

Exclusion Criteria:

• Have severe cognitive impairment, such as a history of head trauma, cerebrovascular disease, epilepsy, etc.
• Have used drugs promoting cognitive function in the last 6 months
• Have impaired intelligence (IQ<70)
• Abuse or dependence of other psychoactive substances (except nicotine) in the last 5 years