Neurons in the human organism are organized in a network-like structure. Within it, they are interconnected via neurophysiological convergence. A neuron receives inputs from various other neurons and sums up these inputs. Brain damage with disruption of neuronal connectivity disrupts this principle of convergence.
What is neurophysiological convergence?
Neurons are organized in a network-like structure in the human organism. In it, they are interconnected via neurophysiological convergence. In neurophysiology, convergence corresponds to an amalgamation of neuronal excitation lines. Each neuronal network consists of a certain number of neurons that are interconnected. In the nervous system, they functionally form a unit. The circuit of neurons has several inputs and at the same time has only one output. Only when the input signals in sum exceed a threshold value does the neuron generate an action potential. This action potential originates in the initial element at the axon hillock of the neuron and travels along the respective axon. An action potential or a series of action potentials corresponds to the primary output signal of any neuronal communication. Only at biochemical synapses do action potentials convert into transmitter quanta and then correspond to secondary signals. The merging of multiple, neuronal excitation inputs into a single output corresponds to neurophysiological convergence. It is what allows excitations to sum up to above the predefined threshold that gives rise to an action potential. Frequently, in connection with the switching technology of the brain, we also speak of connectivity. In the broadest sense, convergence means that different signals from different neurons can be fed to a neuron via its dendrites. The term convergence is also used in ophthalmology.
Function and task
Neurons are the individual, electrical elements of the human organism. Like the individual components in electrical engineering, the electrical components in the human organism must be precisely interconnected in order to function and conduct. The connectivity of neurons makes neurophysiological convergence possible. The nervous system of all living beings contains glial cells in addition to neurons and has a specific environment. Connecting synapses are located between neurons. Thus, these synapses correspond to the point of connection and thus to the nodes in the interneuronal network. However, the neurons are also connected to the glial cells and exchange chemical and electrical signals with them. This exchange changes the weighting of the signals. For this reason, glial cells are sometimes called managers and organizers of the central nervous system. Many inputs to neurons are connected to form a single output. In neurophysiological convergence, the input signals from the individual inputs add up to a threshold value, which causes the neuron to send an action potential or series of action potentials on their way from its one output. Accordingly, connectivity leads to neurophysiological convergence, and this convergence in turn gives rise to the primary output signals of the nervous system. The axons of neurons are highly branched. Thus, the signal from a single neuron is transmitted to many other neurons. This connection is also called neurophysiological divergence. At the same time, the neuron receives the signals of many other neurons through the dendrites and thus operates with convergence. The principles of divergence and convergence are essential basic principles of the neural network and thus also play a role, for example, in the learning ability of neural networks.
Diseases and disorders
Neuronal convergence is essentially dependent on the connectivity of neurons. When the neural plexus in the brain is damaged, this connectivity, and with it neurophysiologic convergence, is disrupted. Damage to the neural plexus can be due to a variety of causes. The circuits in the brain and nervous system have enormous precision, the prerequisite for which is a complex and intact structure. Irregularities or disturbances within the system compensate themselves automatically up to a certain degree.Therefore, after actual damage to the brain structure, severe disturbances occur that can no longer be intercepted. The electrical and biochemical network loses connectivity. Neurological or psychiatric diseases are the result. The location and type of damage determined the disorders that occur. Since many nerve cell structures are involved in a multitude of individual functions thanks to connectivity and convergence, even local damage to the neuronal network can result in extensive consequences with clinically far-reaching symptoms. Sometimes the most common cause of damage to the brain is inadequate blood flow. The brain is constantly working and for this reason has the greatest energy demand among the organs. An interruption in the blood supply corresponds to an interruption in the supply of nutrients as well as oxygen. Insufficient blood supply is caused, for example, by cardiac strokes or hypoglycemia. Sometimes, however, brain tumors also cause a pathological change in the blood vessels. The same applies to mechanical injuries in accidents, after bleeding in the brain and due to inflammations. Often, disturbances in signal transmission between nerve cells are the reason for impaired brain function. In some cases, such disorders are preceded by irregularities in the metabolic activity of the nerve cells. However, brain damage can also be caused by genetic factors, such as hereditary diseases that impair the metabolism of nerve cells and thus cause certain substances to accumulate in the brain. External influences such as bacteria, viruses or toxins can also affect the neuronal network and its circuitry. Mercury poisoning, for example, can cause memory loss or muscle tremors. However, the patient’s immune system is also responsible for many disorders of convergence and divergence. In the autoimmune disease multiple sclerosis, the immune system classifies certain cells of the central nervous system as foreign and attacks them. The resulting inflammation partially destroys the connectivity that underlies convergence.
