The role of impulsivity, response inhibition and delay discounting in addictive behaviors

Abstract

Background

Addiction is now generally regarded to be a brain disease with a chronic course and a high probability of relapse even after long periods of abstinence. Recently, attention in the pathogenesis od addictive behaviors has shifted from abnormalities in the reward and motivational systems towards co-occurring abnormalities in decision making such as conflict monitoring and impulsivity. In this presentation, new data on abnormal decision making in substance use disorders and pathological gambling are presented.

Method

A selected review of the recent literature including data from patients with substance use disorders and pathological gambling.

Results

The data currently available show that smokers, alcoholics, drug dependent patients and pathological gamblers all suffer from abnormalities in motor impulsivity and delay discounting problems and that these abnormalities are associated with hypoactivity of the prefrontal cortex (PFC). Data further show that these abnormalities can not be fully attributed to the presence of comorbid axis I or axis II disorders. Recent data also show that activation of the PFC is dependent on adequate error and conflict monitoring by the anterior cingulate cortex (ACC). However, currently no data are available regarding ACC functioning in addicted patients, but it can not be excluded that at least part of the decision making abnormalities are due to deficits in error/conflict monitoring.

Conclusion

Substance dependent patients and pathological gamblers are characterized by serious deficits in decision making and these deficits should be adressed in future treatments for example through medication, EEG- or fMRI-feedback or transcranial magnetic stimulation.