The vagal response is an automatic reflex that happens within your body when your vagas nerve is stimulated. This reflex affects your central and peripheral nervous system, as well as your cardiovascular system and therefore a sudden stimulation of this reflex can set off a variety of symptoms.
Deep sea zones. The deep sea or deep layer is the lowest layer in the ocean, existing below the thermocline and above the seabed, at a depth of 1000 fathoms (1800 m) or more. Little or no light penetrates this part of the ocean, and most of the organisms that live there rely for subsistence on falling organic matter produced in the photic zone.
Layers of the pelagic zone. The abyssal zone or abyssopelagic is a layer of the pelagic zone of the ocean. Abyss derives from the Greek word á¼Î²ÏÏÏÎ¿Ï, meaning bottomless. At depths of 4,000 to 6,000 metres (13,123 to 19,685 feet), this zone remains in perpetual darkness and never receives daylight.