Introduction: One of the basic functions of the brain is to navigate in space. This ability depends on the ability to have a sense of location which in turn is interconnected with a sense of direction, distance and knowledge of previous locations through which a person has travelled. A man depends on it for daily tasks ranging from finding his car keys to locating his house. In the case of animals they do not react passively to external stimuli. Rather they learn facts about the world and use them when required. This was discovered by Edward Tolman. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an original essay The hippocampus and its function: Hippocampus is the Greek name for a mythical sea monster, hippopotamus means "horse" and kampos means "sea monster". When a hippocampus is cut in cross section, it resembles a ram's horn. For a long time, research has been aimed at understanding the mechanism and role of the hippocampus in memory formation. Discovery of place cells in the hippocampus: Neuronal recording of single cells in awake rats was cutting-edge technology in the late 1960s. With the help of the brain atlas, small wire electrodes were guided to specific areas of interest in the brain. When the electrode tip is close to a neuron, the electrode can record that neuron's action potentials. During an experiment with the rat Jhon O;Keefe, an expert in recording neurons using this technique, recorded neuronal activity in the hippocampus when the animal was performing a variety of behaviors. This approach proved to be quite faithful because they discovered neurons in the rat's hippocampus that showed activity related to the rat's position in its environment. They called these neurons “place cells”. It places fire cells when the animal moves to a specific location in the environment, which corresponds to the place field of that particular neuron. Cells from this location were first found in the pyramidal cell layer of area CA1 of the hippocampus. Subsequently, other groups demonstrated that the CA3 area of ​​the hippocampus is also equipped with place cells. The placement of cells that fire in one part of the animal's environment is not due to anything the animal does there or its motivation for going to that place. Rather, they appear to be a cognitive process, signaling the animal's position within an environment independently of its behavior and motivational state or reward properties of that location. John O'Keefe's discovery of place cells in the hippocampus has created a new surge of interest in the field despite the skepticism of some researchers. Remapping of placement cells: in 1987 Bob Muller and colleagues discovered that the maps of placement cells are completely different in two environments, knowing the location of the firing range in the first environment will not predict the location of the firing range in the second environment. Changing the shape of an enclosure invariably induces a complete remapping. In short, the hippocampal spatial map is sensitive to non-spatial factors, and understanding these factors will be essential for decoding the relationship between hippocampal maps and memory. Head direction cells and boundary cells: To maintain spatial orientation and guide navigation, an animal must be aware of its location, displacement, or distance and direction from that location. We now know that place cells could be used for identification.