Amplitude low-frequency oscillation abnormalities in the heroin users: a resting state fMRI study

Functional neuroimaging studies have revealed abnormal functional organization of the heroin users' brain, including reward circuit, cognitive control circuit, memory circuit, motivation and salience evaluation circuits and so on. In the current study, we aimed to explore the functional changes in the regional brain of heroin users using the amplitude of low-frequency oscillations in the Blood Oxygenation Level Dependent (BOLD) signals. With fMRI data acquired during resting state from 24 chronic heroin users (all subjects were being treated with methadone) and 24 non-addicted controls, we investigated addiction related altered in the amplitude low-frequency fluctuate (ALFF) between the two groups. Compared with controls, we found that heroin addicts had decreased ALFF in the bilateral dorsal anterior cingulate cortex (dACC), bilateral medial orbit frontal cortex (mOFC), left dorsal lateral prefrontal cortex (dlPFC), left middle temporal gyrus, left inferior temporal gyrus, posterior cingulate cortex and left cuneus as well as increased ALFF in the bilateral angular gyrus, bilateral precuneus, bilateral supramarginal gyrus, left post cingulate cortex and left middle frontal gyrus. Moreover, we also found that the increased ALFF in the bilateral parietal lobe had a significantly positive correlation with the methadone does, thus we inferred that the reduced ALFF may due to heroin consumption, nevertheless, the increased ALFF in the bilateral parietal lobe may have resulted from the methadone treatment. This resting-state fMRI study suggests that the changed spontaneous neuronal activity of these regions may be implicated in the underlying pathophysiology of heroin addicts.