Chronic stimulant abuse is associated with both impairment in decision making and structural abnormalities in brain gray and white matter. Recent data suggest these structural abnormalities may be related to functional impairment in important behavioral processes. In 15 cocaine-dependent and 18 control subjects, we examined relationships between decision-making performance on the Iowa Gambling Task (IGT) and white matter integrity as measured by diffusion tensor imaging (DTI). Whole brain voxelwise analyses showed that, relative to controls, the cocaine group had lower fractional anisotropy (FA) and higher mean of the second and third eigenvalues (λ⊥) in frontal and parietal white matter regions and the corpus callosum. Cocaine subjects showed worse performance on the IGT, notably over the last 40 trials. Importantly, FA and λ⊥ values in these regions showed a significant relationship with IGT performance on the last 40 trials. Compromised white matter integrity in cocaine dependence may be related to functional impairments in decision making.

An assay in which groups perform at both similar and significantly different levels within the same test session may have experimental advantages both in understanding underlying behavioral-cognitive processes and in helping to resolve neuroimaging issues regarding functional significance vs. performance confounds. Here we report behavioral data from a response inhibition (Go/No-Go) task with two levels of No-Go difficulty (easy, hard). The sample included individuals with current cocaine dependence (N = 18) and controls (N = 15). Using signal detection methodology (d′ and Beta), significant main effects were observed for group and trial type on d′. Post-hoc analyses revealed the cocaine-dependent individuals performed significantly worse than controls on difficult, but not easy, trials. Differences on d′ but not Beta, and slower reaction times in cocaine subjects, suggest that response inhibition deficits were related to disruption in visual information processing rather than inhibition of motor activity.

Suicidal ideation refers to thoughts about or a preoccupation with killing oneself, while suicide attempts involve actual acts of self-harm with the intent to die.¹ Suicidality encompasses both suicidal ideation and suicide attempts and is strongly predictive of youth suicide deaths and warrants attention. It is more prevalent among adolescents than adults, and several studies have revealed increasing trends in adolescent suicidality over the past decades.^2-5 In the US National Comorbidity Survey, 12.1% of adolescents reported serious thoughts of suicide, and approximately one-third of those with suicidal ideation attempted suicide before reaching adulthood.⁶ Rates of emergency department (ED) visits for intentional self-harm in 2020 were highest among adolescents aged 15 to 19 years compared with older age groups (472 vs 133 per 100 000),² and youth suicidal ideation or suicide attempt rates in the US nearly doubled from 2008 to 2015.⁵