Theta wave

The theta rhythm is an oscillatory pattern in electroencephalography(EEG) signals recorded either from inside the brain or from electrodes glued to the scalp. Two types of theta rhythm have been described. The "hippocampal theta rhythm" is a strong oscillation that can be observed in the hippocampus and other brain structures in numerous species of mammals including rodents, rabbits, dogs, cats, bats, and marsupials. "Cortical theta rhythms" are low-frequency components of scalp EEG, usually recorded from humans.

Union science has developed Brain wave control technology  that led to the develoment  of Sleep Inducers and Stress Control Meditation capsules.

There are also systems to induce feelings of panic, fear and angst. Such systems have often been used as part of Intruder control systems, creating strong feelings of fear that are then triggered with low or high frequency sounds, strobed laser light and cold or hot air.

The same effects were and are used in amusement parks and virtu show experiences.

Theta wave control is effective in 90 percent of all carbon based life forms and even was shown effective against Narth ,(they have now adjusted their physiology to be immune to it)