- Investigate effects of bilateral DLPFC tDCS on large-scale brain networks - DMN (default mode network) - ECN (executive control network) - SN (salience network) - Examine drug craving modulation after tDCS

The human brain as an interconnected system of specialized modules. Functional networks' intrinsic organization and importance. Resting state fMRI (rs-fMRI) for studying brain connectivity. Altered functional connectivity in psychopathological conditions. Significance of large-scale networks in addiction and substance use disorders. Transcranial Direct Current Stimulation (tDCS) as a neuromodulation technique. Increasing interest in tDCS effects on functional brain networks.

- Double-blind sham-controlled crossover study - Participants: 15 males with methamphetamine use disorder - Real tDCS (2 mA) applied over DLPFC on separate days - Resting state fMRI before and after tDCS - Subjective craving assessment before and after fMRI

- Subjective craving decreased after real tDCS vs. sham - DMN: Decreased connectivity after real tDCS (PCC, precuneus, etc.) - ECN: Increased connectivity after real tDCS (right inferior parietal) - SN: Increased connectivity after real tDCS (right insula, frontal regions)

- Alterations in DMN, ECN, and SN after tDCS - DMN and ECN alterations related to attentional resource redirection - Potential of tDCS as a network intervention strategy - Importance of resting state fMRI in monitoring interventions

tDCS-induced alterations in large-scale brain networks. Potential implications for addiction treatment. Importance of understanding network-level effects. Future research directions and clinical applications.