How does rohypnol affect the brain?

Many ways: it is an intermediate acting benzodiazepine used as an hypnotic, sedative, anticonvulsant, anxiolytic, and skeletal muscle relaxant drug. if you use it infrequently, just helps you to calm down for sleep. Long-term use can lead to dependence. Withdrawals are bad – could lead to seizures. Do not take it for long time – you will feel anxious all the time even though you take a coming medication

Many possible ways: Rohypnol can cause anterograde amnesia, loss of inhibition, sedation, confusion, dizziness, disorientation, respiratory depression, difficulty with speech, poor judgement & addiction.