Neurotransmission

Neurotransmission typically requires the release of the endogenous chemical "neurotransmitter" at the synapse between adjacent neurons. Neurotransmitters are synthesized and stored in the axons of nerve cells and released upon intracellular Ca 2+ increase caused by action potentials. It releases the neurotransmitter to the synapse, where it can function in postsynaptic neurons. They act by binding to the receptor (usually a ligand-gated ion channel or GPCR) and by causing ion influx to depolarize the postsynaptic membrane, or by initiating a complex signal cascade. Both of these effects initiate the action potential of postsynaptic neurons and propagate energy waves downstream. Synapse signal and action potential are part of the brain's ability to process all information

The strength of the relationship between neurotransmission and neurons depends on various factors. This includes the number of synaptic contacts between the two neurons, the magnitude of postsynaptic depolarization caused by neurotransmitters, and the possibility of neurotransmitter release. Many neurological diseases can be caused by neurotransmitter defects in neuronal synapses. Since this may not result in impulses to reach postsynaptic neurons, downstream neurotransmitters will not respond. Some examples of diseases with altered neurotransmission include schizophrenia, depression, attention deficit hyperactivity disorder, anxiety disorder, and Alzheimer's disease. Changes in neurotransmission are also associated with drug poisoning

As mentioned above (Figure 3), information is transmitted in the brain through a process called neurotransmission. Neurotransmitters contain various chemical substances called "neurotransmitters". One such neurotransmitter is known as "dopamine". During normal communication, dopamine is released into the synapse by neurons (small gaps between neurons). Later dopamine binds to specific proteins on adjacent neurons called "dopamine receptors" (see figure) and signals the neurons.

Chemical neurotransmission occurs at a chemical synapse. In chemical neurotransmission, presynaptic neurons and postsynaptic neurons are separated by small gap-synaptic gaps. The synaptic cleft is filled with extracellular fluid (all cells immersed in the brain). Although very small, usually on the order of a few nanometers (one billionth of a meter), the synaptic gap creates physical barriers to transfer the electrical signal carried by one neuron to another neuron. Electrically, the synapse clearance is considered a "short circuit" in the circuit. The function of the neurotransmitter is to overcome this electrical short circuit. It acts like a chemical messenger that ties the action potential of one neuron to the synaptic potential of another neuron. How this happens is explained in the animation below.