Neurons were randomly divided into five groups: a control group, a sham group, and three groups which received magnetic stimulation at 40% (1 Hz, 1.68 T), 60% (1 Hz, 2.52 T), and 100% (1 Hz, 4.2 T).8 (link) The control group was placed in the incubator without any treatment. For the stimulated groups, rTMS was delivered with a MCF-B65 butterfly coil9 (link) (Medtronic company, Denmark) with a 80 mm outer diameter connected to a MagPro R30 magnetic stimulation device of 4.2 T maximum output. The coil produced a focal field with the maximal intensity at the intersection of the round components.10 (link) The stimulator handle was fixed on the top of each set of six-well plates with neuron culture platforms by a bracket and parallelled to the Petri dish at a distance of about 1 cm,9 (link) without direct contact.11 (link) Stimulation occurred at a fixed time every day for 5 consecutive days, with the stimulus parameters set at 1 Hz frequency, and intensity of 1.68, 2.52, and 4.2 T corresponding to the 40%T, 60%T and 100%T group, respectively. The stimulus pattern consisted of 3 pulse trains, each containing 100 pulses at 1 Hz, and 60-s interval among sequences. Cells in the sham stimulation group were placed in the magnetic field environment with the same coil, yet the coil was disconnected from the power supply.