COMMENTS: Unique study, which shows that relapse caused specific brain changes in the regions associated with impulse control and decision making (frontal lobes)
September 20th, 2012 in Psychology & Psychiatry
Scientists at Charité – Universitätsmedizin Berlin have succeeded in coming closer to determining the risk of relapse in detoxified alcohol-dependent patients. Using an imaging process (magnetic resonance tomography) it was shown that particular regions in the brain demonstrate structural as well as functional abnormalities in relapsed alcohol-dependent patients. Study findings are published in the journal Archives of General Psychiatry.
In the study conducted under the direction of Prof. Andreas Heinz, director of the Charité Department of Psychiatry and Psychotherapy, scientists examined a group of 46 detoxified alcohol-dependent patients, in addition to a large control group. Structural imaging showed anatomical properties of brain substance, and the examination of functional signals in the brain were measured in reaction to alcohol-associated stimuli. After three months, patients were reexamined for eventual relapses; 30 study participants relapsed and 16 continued to be abstinent.
It was proven that relapse patients had increased loss of grey matter in particular regions of the forebrain. This section of the brain is known to be associated primarily with behavioral regulation and emotional control. Furthermore, measurement of functional brain responses in reaction to alcohol-associated stimuli showed that different brain regions were activated in relapsed patients than in patients who remained abstinent. These measurements show that sections of the brain in relapse patients were active that are associated primarily with directing attention to certain stimuli. In contrast, the abstinent patients demonstrated an activation of brain areas that are (among other functions) associated with processing of stimuli inducing aversion (aversive stimuli) or that are particularly important (salient stimuli).
“This characteristic in patients who remained abstinent possibly acts as a warning signal and prevents potential relapse when confronted with alcohol,” said Anne Beck, primary author of the study. Future studies could examine these aspects in greater depth and take eventual factors of alcohol dependency into consideration, like for example, genetic mechanisms. Thus people with a particularly high risk of relapse could be identified and systematically supported with therapy.
More information: Beck A, Wüstenberg T, Genauck A, Wrase J, Schlagenhauf F, Smolka MN, Mann K, Heinz A. Effect of brain structure, brain function, and brain connectivity on relapse in alcohol-dependent patients. Arch Gen Psychiatry. doi:10.1001/
“Structural and functional abnormalities found in brains of relapsed alcohol-dependent patients.” September 20th, 2012. http://medicalxpress.com/news/2012-09-functional-abnormalities-brains-relapsed-alcohol-dependent.html
Effect of Brain Structure, Brain Function, and Brain Connectivity on Relapse in Alcohol-Dependent Patients
ABSTRACT
Context In alcohol-dependent patients, brain atrophy and functional brain activation elicited by alcohol-associated stimuli may predict relapse. However, to date, the interaction between both factors has not been studied.
Objective To determine whether results from structural and functional magnetic resonance imaging are associated with relapse in detoxified alcohol-dependent patients.
Design A cue-reactivity functional magnetic resonance experiment with alcohol-associated and neutral stimuli. After a follow-up period of 3 months, the group of 46 detoxified alcohol-dependent patients was subdivided into 16 abstainers and 30 relapsers.
Setting Faculty for Clinical Medicine Mannheim at the University of Heidelberg, Germany.
Participants A total of 46 detoxified alcohol-dependent patients and 46 age- and sex-matched healthy control subjects
Main Outcome Measures Local gray matter volume, local stimulus–related functional magnetic resonance imaging activation, joint analyses of structural and functional data with Biological Parametric Mapping, and connectivity analyses adopting the psychophysiological interaction approach.
Results Subsequent relapsers showed pronounced atrophy in the bilateral orbitofrontal cortex and in the right medial prefrontal and anterior cingulate cortex, compared with healthy controls and patients who remained abstinent. The local gray matter volume–corrected brain response elicited by alcohol-associated vs neutral stimuli in the left medial prefrontal cortex was enhanced for subsequent relapsers, whereas abstainers displayed an increased neural response in the midbrain (the ventral tegmental area extending into the subthalamic nucleus) and ventral striatum. For alcohol-associated vs neutral stimuli in abstainers compared with relapsers, the analyses of the psychophysiological interaction showed a stronger functional connectivity between the midbrain and the left amygdala and between the midbrain and the left orbitofrontal cortex.
Conclusions Subsequent relapsers displayed increased brain atrophy in brain areas associated with error monitoring and behavioral control. Correcting for gray matter reductions, we found that, in these patients, alcohol-related cues elicited increased activation in brain areas associated with attentional bias toward these cues and that, in patients who remained abstinent, increased activation and connectivity were observed in brain areas associated with processing of salient or aversive stimuli.
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