[85] It is well established that lesions of the medial septum—the central node of the theta system—cause severe disruptions of memory. Cortical patterns are altered, and a reduction in the volume and thickness of the cortex particularly in the frontal and temporal lobes has been noted. [46][75] Speed cells are thought to provide input to the hippocampal grid cells. [46] In some cases, the firing rate of hippocampal cells depends not only on place but also the direction a rat is moving, the destination toward which it is traveling, or other task-related variables. This dendritic retraction is reversible. Hindbrain - regulates autonomic functions and coordinates movement.
The right head of the hippocampus is more involved in executive functions and regulation during verbal memory recall. It is divided into three fields (CA1, CA2, and CA3) that process, send, and receive input from other brain regions. © 2004-2020 Healthline Media UK Ltd, Brighton, UK, a Red Ventures Company. This would preserve and potentially improve memory. [86] However, the medial septum is more than just the controller of theta; it is also the main source of cholinergic projections to the hippocampus. Scientists are unsure exactly how this occurs. Hippocampus removed from the brain (left), in comparison to a seahorse. It contains two main interlocking parts: the hippocampus proper (also called Ammon's horn)[4] and the dentate gyrus. Spatial relationship memories involve pathways or routes. The hippocampus is also where short-term memories are turned into long-term memories.

The hippocampus, including the dentate gyrus, has the shape of a curved tube, which has been compared to a seahorse, and a ram's horn (Cornu Ammonis).

[42][51] Part of this function is hippocampal involvement in the detection of new events, places and stimuli. It has been suggested that on the basis of experimental work using animals, hippocampal dysfunction might produce an alteration of dopamine release in the basal ganglia, thereby indirectly affecting the integration of information in the prefrontal cortex. Because the hippocampus is thought to play a central role in memory, there has been considerable interest in the possibility that age-related declines could be caused by hippocampal deterioration. Sharp waves in Hebbian theory are seen as persistently repeated stimulations by presynaptic cells, of postsynaptic cells that are suggested to drive synaptic changes in the cortical targets of hippocampal output pathways.
What Does the Brain's Cerebral Cortex Do? London’s black cab drivers need to learn the locations of a large number of places and the fastest routes between them in order to pass a strict test known as The Knowledge in order to gain a license to operate. [20], The major input to the hippocampus is through the entorhinal cortex (EC), whereas its major output is via CA1 to the subiculum. Declarative memories are those related to facts and events. It has also been linked to conditions such as schizophrenia and post-traumatic stress disorder (PTSD). These … In adult humans the volume of the hippocampus on each side of the brain is about 3.0 to 3.5 cm3 as compared to 320 to 420 cm3 for the volume of the neocortex. There is little, if any, spatial topography in the representation; in general, cells lying next to each other in the hippocampus have uncorrelated spatial firing patterns.