Device for operating a system for neurofeedback training on a subject that includes training of an animal; - wherein the said system comprises at least one user module, a mobile module and optionally - option modules (30, 40) selected from one or more separated modules placed in a NFB performance area and animal modules placed on an animal (101, 102); - wherein the said user module is equipped with: a set of electroencephalographic electrodes for brainwave recording, an EEG amplifier, a data processing unit that transforms EEG signals to electronic information suitable for a wireless transfer, a pairing unit that enables connectivity with other units (20, 30, 40) and an ultrasonic speaker for communication with the animal (101, 102); - wherein the mobile module is equipped with a data processing unit that processes received EEG signals of one or more subjects, a pairing unit that enables connectivity with other units (10, 30, 40); an animal training unit, a control unit and an internet connection with data cloud all connected with the mentioned data processing unit; - wherein each option module (30, 40) is equipped with a corresponding data processing unit (33, 34), a pairing unit (10, 20) and an ultrasonic speaker (35, 45) for communication with an animal (101, 102); - wherein the neurofeedback training on subject is performed by the said system in which said feedback chain consists of the steps: A->B->C->D->A where the steps are: A. real time recording of the subject's EEG performed by the user module and forwarded to the mobile module by using their respective paired units (14, 24); B. analytics of the signal recorded in the step A. performed by the data processing unit of the mobile module, and algorithmic decisioning about the stimulation form for the subject whose EEG signal has been recorded; C. forwarding the said stimulation form for the subject determined in the step B. towards the animal (101, 102); and D. performing an action by the animal (101, 102), triggered by the said stimulation, which provides a stimulus to the subject exposed to the neurofeedback training of the step A.; wherein - the used animal species (101, 102) are previously trained canine species or dolphin species, susceptible to the ultrasound, which are the only source of visual, tactile or auditory stimulus to the subject; - wherein the information needed for the said animal (101, 102) performance, creating the stimulus for the subject, is forwarded in the form of a coded ultrasonic signal via one or more ultrasonic speakers (14, 34, 44) simultaneously, placed on one or more modules selected from: the user module, the separated module and animal module; wherein all the mentioned modules (10, 30, 40) are paired with the mobile module. - wherein the said system comprises at least one user module, a mobile module and optionally - option modules (30, 40) selected from one or more separated modules placed in a NFB performance area and animal modules placed on an animal (101, 102); - wherein the said user module is equipped with: a set of electroencephalographic electrodes for brainwave recording, an EEG amplifier, a data processing unit that transforms EEG signals to electronic information suitable for a wireless transfer, a pairing unit that enables connectivity with other units (20, 30, 40) and an ultrasonic speaker for communication with the animal (101, 102); - wherein the mobile module is equipped with a data processing unit that processes received EEG signals of one or more subjects, a pairing unit that enables connectivity with other units (10, 30, 40); an animal training unit, a control unit and an internet connection with data cloud all connected with the mentioned data processing unit; - wherein each option module (30, 40) is equipped with a corresponding data processing unit (33, 34), a pairing unit (10, 20) and an ultrasonic speaker (35, 45) for communication with an animal (101, 102); - wherein the neurofeedback training on subject is performed by the said system in which said feedback chain consists of the steps: A->B->C->D->A A. real time recording of the subject's EEG performed by the user module and forwarded to the mobile module by using their respective paired units (14, 24); B. analytics of the signal recorded in the step A. performed by the data processing unit of the mobile module, and algorithmic decisioning about the stimulation form for the subject whose EEG signal has been recorded; C. forwarding the said stimulation form for the subject determined in the step B. towards the animal (101, 102); and D. performing an action by the animal (101, 102), triggered by the said stimulation, which provides a stimulus to the subject exposed to the neurofeedback training of the step A.; - the used animal species (101, 102) are previously trained canine species or dolphin species, susceptible to the ultrasound, which are the only source of visual, tactile or auditory stimulus to the subject; - wherein the information needed for the said animal (101, 102) performance, creating the stimulus for the subject, is forwarded in the form of a coded ultrasonic signal via one or more ultrasonic speakers (14, 34, 44) simultaneously, placed on one or more modules selected from: the user module, the separated module and animal module; wherein all the mentioned modules (10, 30, 40) are paired with the mobile module.