Any ideas about the neural mechanism underlying the ASMR sensation? Autonomous Sensory Meridian Response (ASMR) is described as a pleasurable, tingly sensation in the (back of the) head.
The sensation can be triggered by a vast variety of stimuli (auditory, visual, olfactory etc) but seems dependent on attention. It seems not everyone can get this sensation and among those people that do, stimuli that trigger the sensation vary considerably. See also:
https://en.wikipedia.org/wiki/Autonomous_sensory_meridian_response

But what could be the physical origin of this sensation? And how come only a select group of people seem able to experience it? In http://theness.com/neurologicablog/index.php/asmr/ the ASMR sensation is proposed to be caused by either [1] small seizures or [2] extra sensitivity or extra 'pleasure-shots' to stimuli that for other people are just moderately satisfying. Other sources compare ASMR to meditation.

Does anyone know more about this phenomenon, or have another theory about the mechanism behind it?
I found one study that looked at ASMR and the Default Mode Network (DNM). The DMN consists of the medial prefrontal cortex, medial temporal gyri, bilateral inferior parietal cortices, precuneus and posterior cingulate gyrus. In the study, the DMN of 11 individuals with ASMR was compared with 11 controls. 

The DMN of individuals with ASMR showed significantly less functional connectivity than that of controls. The DMN of individuals with ASMR also demonstrated increased connectivity between regions in the occipital, frontal, and temporal cortices, suggesting that ASMR was associated with a blending of multiple resting-state networks. This atypical functional connectivity likely influences the unique sensory-emotional experiences associated with ASMR.

Reference:

D. L. (2008). The brain’s default network: Anatomy, function, and relevance to disease. Annals of the New York Academy of Sciences, 1124, 1–38. doi:10.1196/annals.1440.011