Stimulation, non-invasive, electromagnetic A means of disrupting normal brain activity by introducing neural noise – ‘virtual lesion’ experiment: if behaviour changes after stimulation it means area is necessary for task, if behaviour stays the same after stimulation then it shows the area only supports. applying TMS pulse at cortical node of network, then efficacy of that signal will be degraded, behavioural decrement (Speed of response) will change, and it will take us longer to read. but advantages of TMS are the virtual lesion technique, transient and reversible, control location of stimulation and establishes a causal link of different brain areas and a behavioural task.