Our work with patients allows us to study cognitive processes and brain functions using causal interventions such as pharmacology, TMS (transcranial magnetic stimulation), VNS (invasive vagus nerve stimulation) and DBS (deep brain stimulation). Pharmacological interventions in our team target NDMA, serotonin and noradrenaline receptors, using ketamine, classic psychedelics and atomoxetine, respectively. TMS, VNS and DBS are three therapeutic approaches that modulate the activity of the nervous system. Whereas TMS is a non-invasive procedure relying on the application of magnetic fields, VNS and DBS use electrical pulses applied to the vagus nerve or to deep brain structures (typically basal ganglia nuclei), respectively. These therapeutic procedures are designed to modulate brain activity and can therefore be used as research models.