The Hippocampus is a small part of the brain located deep inside your head. It’s main function is to store short term memories. These memories are usually made up of visual images or sounds.
There are two types of cells in the hippocampus: Neurons and Glial Cells . Neurons make connections with other neurons and have many different functions such as learning, memory formation, movement, etc.. Glia cells are non-neuronal cells which do not have any particular function but they help keep the body healthy. They secrete chemicals called Neurotransmitters which affect other parts of the body and play a role in regulating moods, emotions, sleep patterns, appetite and much more.
Neurotransmitters are chemical messengers that pass from one neuron to another. Some neurotransmitters are involved in learning, memory formation, emotion regulation and others. There are several kinds of neurotransmitters.
The most common ones include: Serotonin , Dopamine , Norepinephrine , Acetylcholine and Noradrenaline .
A single neuron releases a certain amount of these substances every second. When there is too much serotonin or dopamine in the system, it causes depression or anxiety disorders. This may happen due to stress, drugs and other reasons.
It is also possible for there to be too much acetylcholine or norepinephrine in the brain.
The brain is a very complex organ made up of about 100 billion neurons. A single neuron can make as many as 15,000 connections with other neurons. There are different types of these cells.
The soma is the cell body and has the nucleus and mitochondria. Dendrites are branched projections that carry messages to the soma and axons are long fibers that carry messages away from the soma. The axon of one neuron may touch the dendrite of another. The space between two neurons where the axon terminal touches a dendrite is called a Synapse . A single neuron can make as many as 15,000 of these contacts.The different parts of a neuron.
There are two types of neurotransmitters: Excitatory and Inhibitory Neurotransmitters. These terms show whether a neurotransmitter excites the neurons around it to produce a response or inhibits the response of the neurons around it. For example, Glutamate is an excitatory neurotransmitter and is required for neural stimulation while GABA is an inhibitory neurotransmitter and reduces neural stimulation.
- Segregating the functions of human hippocampus (BA Strange, PC Fletcher… – Proceedings of the …, 1999 – National Acad Sciences)
- Functions of neuronal networks in the hippocampus and neocortex in memory (ET Rolls – Neural models of plasticity, 1989 – Elsevier)
- Behavioral functions of the CA3 subregion of the hippocampus (RP Kesner – Learning & memory, 2007 – learnmem.cshlp.org)
- Possible inhibitory functions of the hippocampus (DP Kimble – Neuropsychologia, 1969 – Elsevier)
- Neurophysiological and theoretical analysis of how the primate hippocampus functions in memory. (ET Rolls, S O’Mara – 1993 – psycnet.apa.org)
- Functions of cannabinoid receptors in the hippocampus (SN Davies, RG Pertwee, G Riedel – Neuropharmacology, 2002 – Elsevier)
- Cellular targets and trophic functions of neurotrophin-3 in the developing rat hippocampus (D Collazo, H Takahashi, RDG McKay – Neuron, 1992 – Elsevier)
- The functions of the preplate in development and evolution of the neocortex and hippocampus (H Super, E Soriano, HBM Uylings – Brain Research Reviews, 1998 – Elsevier)
- Volumes of hippocampus, amygdala and frontal lobes in the MRI-based diagnosis of early Alzheimer’s disease: correlation with memory functions (MP Laakso, H Soininen, K Partanen, EL Helkala… – Journal of neural …, 1995 – Springer)