佛頂尊勝陀羅尼經教跡義記 2.59

2.59

唐云驚覺。解曰：既蒙光觸驚覺身心，懇切歸依有此來意。又解：光從頂發遍照剎塵，其光却收還入佛頂，發起行者，持誦心開光觸有緣，故云驚覺也。

In Chinese it means: "To awaken / startle." The explanation states: Having been touched by the light, one's body and mind are awakened, and one takes refuge with earnest devotion; hence comes this intended meaning. Another explanation: The light radiates from the uṣṇīṣa and universally illuminates worlds as numerous as dust motes; that light is then drawn back and re-enters the uṣṇīṣa, arousing practitioners so that in their recitation their minds open and the light touches those with whom it has affinity; hence it is said "to awaken / startle."