In an integrated transcranial current stimulation and electroencephalography device, data obtained by EEG electrodes is received, amplified, converted, and then processed by a microcontroller that extracts frequency information from the sampled data and produces signals in response to the extracted EEG data. These signals are converted to create a software-definable alternating voltage used to control a current-source that connects to stimulation electrodes. The device may further download recorded EEG data from the microcontroller to a computer for further analysis. Using the device, EEG signals are detected, then received, processed, and analyzed by a microcontroller to identify the patient state. Based on the patient state and the desired protocol, a type and amount of current stimulation to apply to the patient is determined and a control signal is sent from the microcontroller to the current source in order to trigger the transcranial current stimulation of the patient.