Anything might lurch out from nothingness

In terms of the sensory fear of emptiness, such as fear of silence, the fear is not based on isolation but on what may be lurking in the silence. Remember that the root misconception of the air element is groundless anxiety. 

p217, Spectrum of Ecstasy, Ngakpa Chögyam with Khandro Déchen, Aro Books, 1997, ISBN 0-9653948-0-8