One category depends upon external triggers in order to experience the localized sensation and its associated feelings, which typically originates in the head, often reaching down the neck and sometimes the upper back. The other category can intentionally augment the sensation and feelings through attentional control, without dependence upon external stimuli, or 'triggers', in a manner compared by some subjects to their experience of meditation.
The areas that typically work together weren’t firing together as much. Instead, other areas of the brain were getting more involved than usual—areas related to a visual network, for instance. These differences suggest “that instead of having distinct brain networks the way you or I would, there was more of a blending of these networks,” says Smith, who studies the neuroscience of emotion. “It does make intuitive sense that a condition associated with atypical sensory association and atypical emotional association would have different wiring in the brain.”
ASMR is usually precipitated by stimuli referred to as 'triggers'. ASMR triggers, which are most commonly auditory and visual, may be encountered through the interpersonal interactions of daily life. Additionally, ASMR is often triggered by exposure to specific audio and video. Such media may be specially made with the specific purpose of triggering ASMR or originally created for other purposes and later discovered to be effective as a trigger of the experience.