Chunk #37 — 4. Discussion — 4.1. Aberrant FC in Individuals with AUD — 4.1.2. Hypoconnectivity across Anterior–Posterior and Interhemispheric Connections in AUD
individuals showed hypoconnectivity in the long-range anterior–posterior connections, viz., between the medial PFC and the PCC and between the left IPL and the medial PFC [111]. In a study on smoking addiction, Tang et al. [112] reported that smokers had reduced effective connectivity from the PCC to the medial PFC (ACC) and from the IPL to the medial PFC, compared to non-smokers. As mentioned earlier, Huang et al. [103] reported hypoconnectivity in long-range connections across multiple regions of reward and executive processes in AUD patients with excessive craving, in addition to local hyperconnectivity at anterior and posterior regions, while processing alcohol cues. These studies from drug and behavioral addictions suggest that there might be a common substrate for the entire addiction spectrum disorders, which can include addiction for substances and behaviors. On the other hand, hyperconnectivity within prefrontal nodes observed in the current study may be interpreted as a compensatory mechanism to overcome the functional loss due to prefrontal hypoactivity found in abstinent AUD individuals [113]. Furthermore, diffusion tensor imaging (DTI) studies have reported widespread abnormalities in the white matter tracts of associative fibers [114,115] as well as interhemispheric fibers [6,116]. In sum, although these findings support the view that
