https://www.selleckchem.com/products/tat-beclin-1-tat-becn1.html Focusing on the developmental process of the brain, we propose a neural network model of functional differentiation including functional parcellation. We explain the emerging process of functional elements, of the system through the constraints, which act on the whole network system. We explain several kinds of differentiation, such as the differentiation of neuronal cells, functional modules, and the sensory neurons, thereby proposing three hypotheses.To study cortical excitability changes induced by external stimulation with a certain rhythm, we developed a new method using motor evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS) over the primary motor cortex. In this method, three conditioning TMS with the intensity below the motor threshold are given prior to the supra-threshold test stimulus with the four TMSs were separated by a certain interval (triad-conditioning stimulation TCS). In healthy volunteers, MEP facilitation was elicited at an interval of 25ms, whereas TCSs with other intervals induced no facilitation. This frequency-dependent facilitation may reflect some intrinsic rhythm of M1 (25ms, i.e. 40Hz). In cortical myoclonus, the facilitation at 25ms was gone whereas facilitation was elicited by triad-conditioning stimulus at 40ms (25Hz), which is consistent with a previously reported abnormal beta rhythm in cortical myoclonus reported previously. Facilitation at 25ms was evoked in neither Parkinson's disease nor in amyotrophic lateral sclerosis. With TCS, we were able to investigate the intrinsic rhythmic activity of M1 and its changes in neurological disorders.I describe quadripulse stimulation (QPS) briefly, and show several examples of its applications, such as rTMS treatment of Parkinson's disease, gait induction by lumbar rTMS, and roles of presupplementary motor area (pre-SMA) and SMA in visuo-motor sequence learning, role of SMA in negative compatibility