With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Gwen Stefani is the lead guitarist of No Doubt.
text_B: Dopamine dysregulation syndrome -LRB- DDS -RRB- is a dysfunction of the reward system observed in some individuals taking dopaminergic medications for an extended length of time .. reward system. reward system. It typically occurs in people with Parkinson 's disease -LRB- PD -RRB- who have taken dopamine agonist medications for an extended period of time .. dopamine agonist. dopamine agonist. It is characterized by self-control problems such as addiction to medication , gambling , or sexual behavior .. addiction. addiction. gambling. problem gambling. sexual behavior. sexual addiction
not_related.