Increased local and decreased remote functional connectivity at EEG alpha and beta frequency bands in opioid-dependent patients

Abstract

In 22 opioid-dependent patients, we found the evidence that brain functional connectivity was indeed disrupted by chronic opioid abuse (i.e., the local functional connectivity increased and remote functional connectivity decreased in opioid abusers). This significant difference between "opioid" and "control" populations was the same for alpha and beta frequency bands. Additionally, significant negative relations between duration (years) of daily opioid abuse and the number/strength of functional connections in the posterior section of the cortex were found.

Drug Polyconsumption Is Associated With Increased Synchronization of Brain Electrical-Activity at Rest and in a Counting Task

“…A plausible related explanation would be in terms of slowing of cognitive processes, and decreased ability of drug abusers to cope with the demands of a constantly changing environment. 15 This explanation would be consistent with studies on patients under acute opioid influence reporting (i) increases in the size, functional life span, and stability of quasi-stationary brain activity, in both a and ¡3 frequency bands, 15 which diminished but did not disappear during short-term withdrawal, 50 and (ii) with a correlation between life-span of neuronal assemblies and reaction times. 70 Alternatively, enhanced synchronization may reflect enhanced arousal level, when at /?, a plausible interpretation in the case of short-term drug abstinent subjects.…”

“…Consistent with prior suggestions 69 we propose that the brain of drug abusers may undergo a premature form of ageing. Taken together with the result of existing studies, 15 ' 50 our results contribute to the delineation of a time-varying pattern of abnormal long-range synchronization in various stages of drug addiction, from acute dependence to short and medium term withdrawal. Future studies will clarify the extent to which hypersynchronization is permanent, and whether it stems from drug abuse or represents a pre-morbid factor predisposing individuals to drug use and addiction.…”

“…9 Most recently, heroin-dependent subjects, with a two week abstinence period, were found to have increased left fronto-occipital intrahemispheric 7 coherence, as well as higher relative ¡32 power, compared to control subjects. 12 Fingelkurts and colleagues used structural synchrony analysis, 49 to evaluate connectivity in a group of opioid-dependent patients during acute dependence 15 and short-term withdrawal. 50 Opioiddependent patients had significantly decreased remote connectivity at rest, during acute opioid influence, 15 but abnormally enhanced during shortterm withdrawal, i.e.…”

“…12 Fingelkurts and colleagues used structural synchrony analysis, 49 to evaluate connectivity in a group of opioid-dependent patients during acute dependence 15 and short-term withdrawal. 50 Opioiddependent patients had significantly decreased remote connectivity at rest, during acute opioid influence, 15 but abnormally enhanced during shortterm withdrawal, i.e. after a two week detoxification period, 50 for both a and ¡3 frequencies.…”

Effective brain network analysis with resting-state EEG data: a comparison between heroin abstinent and non-addicted subjects

“…It proposes one strategy to analyze brain networks of HA and NA subjects using the advanced tools MVARICA and GPDC on the resting-state EEG data. Differently from previous studies of heroin addiction [7-9, 16, 17], [45][46][47], this work studies the BFS alterations in the source space, and effective connectivity is estimated in the frequency domain.…”