Altered resting-state functional connectivity in male individuals with methamphetamine use disorder at two different withdrawal periods: spotlight on the paraventricular thalamic nucleus.

Preclinical research highlights the paraventricular thalamic nucleus as important in various stages of substance use disorder. However, there is limited research on it in relation to methamphetamine, especially regarding its functional changes after long-term abstinence. This study aims to understand the alterations in functional connectivity of the paraventricular thalamic nucleus in methamphetamine abstainers and its correlation with drug craving at two different withdrawal periods. A total of 49 subjects were allocated to the short-term withdrawal group, 44 to the long-term withdrawal group, and 42 to the healthy control group, all of whom are male and adult. Craving scores were assessed using a visual analogue scale. Functional connectivity was evaluated through resting-state functional MRI, which reflects the correlation between connectivity in different brain regions. Significant differences in functional connectivity between the paraventricular thalamic nucleus and the left caudate nucleus were observed across the three groups. The healthy control group exhibited the strongest connectivity, followed by the long-term withdrawal group, while the short-term withdrawal group demonstrated the weakest connectivity. Within the short-term withdrawal group, functional connectivity of the paraventricular thalamic nucleus with both the left parahippocampal gyrus (r = -0.45, p = 0.001) and the left inferior temporal gyrus (r = -0.43, p = 0.002) was significantly correlated with craving scores. This study confirms abnormalities in the paraventricular thalamic nucleus among male methamphetamine abstainers, emphasizes its potential role in regulating methamphetamine use disorder and craving mechanisms, and offers insights into long-term changes in brain function after abstinence.