High Frequency rTMS Over l-DLPFC in Gambling Disorder

Overview

Gambling disorder (GD), currently considered a behavioral addiction, show substantial similarities with substance use disorders (SUDs) in terms of neurobiology and symptomatology. In particular, alterations in prefrontal control circuit may underlie vulnerability to gambling- and drug-related cues and diminished cognitive control over craving, and negative emotions. Repetitive transcranial magnetic stimulation (rTMS) of the dorsolateral prefrontal cortex (DLPFC) could represent a novel approach to remodel these brain circuits. The aim of this study is to evaluate High frequency (HF) rTMS over the left DLPFC as an efficacious treatment for reduction of gambling urges and behavior in a randomized double-blind placebo-controlled design in which 36 GD patients will receive active or sham rTMS for 12 weeks.

Gambling disorder (GD) is a progressive and recurrent maladaptive pattern of gambling behavior, leading to impaired functioning. GD has been recategorized from an impulse control disorder to an addiction-related disorder in the fifth edition of Diagnostic and Statistical Manual of Mental (DSM-5) reflecting the growing evidence of the substantially overlapping between the neurobiology of GD and substance use disorders (SUDs). Both GD and SUDs are characterized by malfunction in reward, stress and cognitive-control circuits, which underlie manifestations such as compulsive gambling or compulsive drug consumption, craving, altered reward sensitivity, impaired self-control and decision-making processes. Particularly, similar alterations in cortico-limbic-striatal and prefrontal control circuits have been shown associated to the emergence of drug cravings and gambling urges. Hence, craving might be seen as a core component across addictions. Indeed, identifying and targeting the neurocircuit alterations underlying craving, may allow to treat this feature across different addictions with similar strategies. In this regard, High frequency (HF) repetitive transcranial magnetic stimulation (rTMS) over the left dorsolateral prefrontal cortex (l-DLPFC), is a promising approach for modulating brain circuits underlying cue-induced craving. Since alterations in these circuits have been shown to underlie the emergence of gambling urges, HF rTMS may represent a potential treatment also for GD patients. Thus, the main goals of this clinical trial are to 1) assess whether HF rTMS over l-DLPFC reduces urges to gamble and problem behaviors gambling related; 2) investigate whether rTMS induces hemodynamics changes in DLPFC activity in response to specific tasks that elicit such areas as visual stimuli associated with gambling; 3) assess whether rTMS induces improvements in decision making processes of GD patients; and 4) evaluate the effects of HF rTMS over l-DLPFC on resting functional connectivity, focusing mainly in connectivity changes of cortical and subcortical regions involved in this disorder.