Low-intensity focused ultrasound targeting the nucleus accumbens as a potential treatment for substance use disorder: safety and feasibility clinical trial

Research on suicide prevention and interventions requires a standard method for assessing both suicidal ideation and behavior to identify those at risk and to track treatment response. The Columbia-Suicide Severity Rating Scale (C-SSRS) was designed to quantify the severity of suicidal ideation and behavior. The authors examined the psychometric properties of the scale. The C-SSRS's validity relative to other measures of suicidal ideation and behavior and the internal consistency of its intensity of ideation subscale were analyzed in three multisite studies: a treatment study of adolescent suicide attempters (N=124); a medication efficacy trial with depressed adolescents (N=312); and a study of adults presenting to an emergency department for psychiatric reasons (N=237). The C-SSRS demonstrated good convergent and divergent validity with other multi-informant suicidal ideation and behavior scales and had high sensitivity and specificity for suicidal behavior classifications compared with another behavior scale and an independent suicide evaluation board. Both the ideation and behavior subscales were sensitive to change over time. The intensity of ideation subscale demonstrated moderate to strong internal consistency. In the adolescent suicide attempters study, worst-point lifetime suicidal ideation on the C-SSRS predicted suicide attempts during the study, whereas the Scale for Suicide Ideation did not. Participants with the two highest levels of ideation severity (intent or intent with plan) at baseline had higher odds for attempting suicide during the study. These findings suggest that the C-SSRS is suitable for assessment of suicidal ideation and behavior in clinical and research settings. Show more

Drug addiction represents a dramatic dysregulation of motivational circuits that is caused by a combination of exaggerated incentive salience and habit formation, reward deficits and stress surfeits, and compromised executive function in three stages. The rewarding effects of drugs of abuse, development of incentive salience, and development of drug-seeking habits in the binge/intoxication stage involve changes in dopamine and opioid peptides in the basal ganglia. The increases in negative emotional states and dysphoric and stress-like responses in the withdrawal/negative affect stage involve decreases in the function of the dopamine component of the reward system and recruitment of brain stress neurotransmitters, such as corticotropin-releasing factor and dynorphin, in the neurocircuitry of the extended amygdala. The craving and deficits in executive function in the so-called preoccupation/anticipation stage involve the dysregulation of key afferent projections from the prefrontal cortex and insula, including glutamate, to the basal ganglia and extended amygdala. Molecular genetic studies have identified transduction and transcription factors that act in neurocircuitry associated with the development and maintenance of addiction that might mediate initial vulnerability, maintenance, and relapse associated with addiction. Show more