What is the Jacobson's Organ? Jacobson's Organ and the Sixth Sense. Traditionally humans have been thought to come equipped with five senses: sight, hearing, taste, touch, and smell. Animals possess several extra senses, including altered vision and hearing, echolocation, electric and/or magnetic field detection, and supplementary chemical detection senses. In addition to taste and smell, most vertebrates use Jacobson's organ (also termed the vomeronasal organ and vomeronasal pit) to detect trace quantities of chemicals. While snakes and other reptiles flick substances into Jacobson's organ with their tongues, several mammals (e.g., cats) exhibit the Flehmen reaction. When 'Flehmening', an animal appears to sneer as it curls its upper lip to better expose the twin vomeronasal organs for chemical sensing. In the 1800s, Danish physician L. Since extra-sensory perception or ESP is awareness of the world beyond the senses, it would be inappropriate to term this Sixth Sense 'extrasensory'.
Additional Reading. Jacobsons organ in Humans? - The Naked Scientists October 2007. This week's Question was answered by Peter Brennan, Department of Physiology and Pharmacology, University of Bristol... The Jacobson's organ is part of the vomeronasal system. It senses chemical stimuli such as marks, which tell animals about the sex and individual identity of other members of their species, often called pheromones. The Jacobson's organ is found in many species but by no means, all species. The question is, whether or not there's a Jacobson's organ in humans.
People have found a small in-folding in the nose of humans and claimed that to be a Jacobson's organ. The question is, whether or not it is functional? The overwhelming weight of evidence is against this function. Diana: So there is some evidence for its existence in humans, but it seems unlikely that our brains are actually receiving any information from it. Vomeronasal organ. The vomeronasal organ (VNO), or Jacobson's organ, is an auxiliary olfactory sense organ that is found in many animals. It was discovered by Frederik Ruysch prior to 1732 and later by Ludwig Jacobson in 1813.[1] This organ is the sense organ involved in the flehmen response in mammals.
The VNO is the first stage of the accessory olfactory system and contains sensory neurons that detect chemical stimuli. The axons from these neurons project to the accessory olfactory bulb, which targets the amygdala and bed nucleus of the stria terminalis, which in turn project to the hypothalamus. The vomeronasal organ is mainly used to detect pheromones, chemical messengers that carry information between individuals of the same species.
Its presence in many animals has been widely studied and the importance of the vomeronasal system to the role of reproduction and social behavior (through influence on anterior hypothalamus) has been shown in many studies. Structure[edit] Function[edit] Animals[edit] Jacobson's organ. Jacobson's Organ.