Functional and Structural Alteration of Default Mode, Executive Control, and Salience Networks in Alcohol Use Disorder

Abstract

Alcohol use disorder (AUD) has been related to aberrant functional connectivity (FC) in the salience network (SN), executive control network (ECN), and default mode network (DMN). However, there is a lack of comprehensive and simultaneous examination of these networks in patients with AUD and of their relation to potential anatomical changes. We aimed to comprehensively examine the alteration in FC in the three networks in AUD patients, and the correlation of the alteration with anatomical/structural changes (volume) in the neural areas implicated in these networks, by applying voxel-based morphometry (VBM) and region of interest-to-region of interest connectivity analysis simultaneously. In all, 22 patients with AUD and 22 healthy adults participated in the study and underwent T1 magnetic resonance imaging. Patients with AUD showed increased FCs within the DMN and SN networks, especially in terms of connectivity of the frontal areas and bilateral hippocampi. They also showed decreased FCs in the ECN. In addition, there was significant volume reduction in these areas (frontal areas and hippocampus). The increased FCs within the frontal areas or bilateral hippocampi showed a negative correlation with gray matter volume of these areas in AUD patients. Our findings add to the empirical evidence that the frontal lobe and hippocampi are critical areas that are vulnerable to functional and structural changes due to AUD.

Differences in Brain Network Topology Based on Alcohol Use History in Adolescents

“…Muller-Oehring found that weaker internetwork connectivity in the DMN was associated with hazardous alcohol consumption in adolescence, a finding reflected in a number of additional alcohol use studies [33,49,71]. Additionally, abnormal SN and DMN connectivity have been implicated in cocaine use in adults [63,87,88]. Although we did not observe significant within-network drinking group differences in DMN topology, results from our three-way interactions revealed that the topological differences observed in the DMN were opposite of that observed in the rest of the brain, suggesting that that DMN topology may be associated with alcohol consumption in adolescence.…”

Global, interhemispheric and intrahemispheric functional connection patterns in male adults with alcohol use disorder

“… 38 The thalamus and caudate both belong to the basal ganglia network, thus implying that the basal ganglia network is also associated with the severity of AUD. 39 Numerous studies have suggested that the thalamus might be an important brain node with an abnormal pattern of functional connection in multiple networks in AUD, including the basal ganglia network, 39 reward network, 40 salience network, 41 executive control network, 41 and default mode network. 39 , 41 Our findings also detected abnormal global, interhemispheric and intrahemispheric FCD of the thalamus, predominantly in the anterior nucleus, which is principally connected to the hippocampus and responsible for amnesia in individuals with AUD.…”

Executive function deficit in betel quid‐dependence: Evidence from functional and effective connectivity of executive control network

“…Prior studies suggested that individuals with addictive disorders showed reduced functional connectivity of the ECN. 18,29 The ECN is engaged in high-level cognitive functions such as working memory, inhibitory control, executive control and goal-directed behaviour. 9,10 Functional impairment of the ECN underlies deficits in executive function that characterize addictive disorders.…”

“…15,16 Naturally, ECN disruption is widespread in addictive disorders, including alcohol, internet and nicotine addiction. [17][18][19] The disrupted patterns of deficits in the structure and function of the ECN were recognized as the crucial determinant for the development and maintenance of addiction. 16,20,21 Nevertheless, few studies have investigated the mechanism underlying ECN dysfunction in patients with BQD.…”

“…The addictive disorders share common symptoms of disinhibited behaviour, loss of self‐administration and deficit cognitive function (i.e., impaired executive functioning, poor decision‐making) 15,16 . Naturally, ECN disruption is widespread in addictive disorders, including alcohol, internet and nicotine addiction 17–19 . The disrupted patterns of deficits in the structure and function of the ECN were recognized as the crucial determinant for the development and maintenance of addiction 16,20,21 .…”