A neuron is a nerve cell that is the basic building block of thecentral nervous systemandperipheral nervous system.
Neurons are specialized in transmitting information throughout the body so we can walk, talk, and process information.
Overview
These highly specialized nerve cells are responsible for communicating information in both chemical and electrical forms.
Science Photo Library - KTSDESIGN/Getty Images
They come in different shapes and sizes depending on their specific location and purpose.
The dendrites and axons extend from the cell body.
Dendritesare the extensions that branch off of the cell body and receive signals from other neurons.
Theaxonextendsfrom the cell body and is what we commonly refer to as a nerve fiber.
The axon transmits information away from the cell body to the nerve ending.
They also work together to perform complex functions in the human body.
Sensory neurons help you taste, see, hear, and smell.
We can also feel touch, pressure, and temperature.
There are two types: upper motor neurons and lower motor neurons.
Upper motor neurons originate in the primary motor cortex of the brain and travel down the spinal cord.
Interneuronsare responsible for communicating information between sensory and motor neurons via the spinal cord and brain.
Complex movements such as walking and talking require the coordination of many muscles.
This involves a sensory-motor feedback loop that allows for fine-tuning of gestures in real time.
Interneurons also assist withreflexive actions, like pulling your hand off of the hot stove.
How Neurons Communicate
How do neurons transmit and receive information?
This process utilizes both electrical signals as well as chemical messengers.
The neuron sending the signal is called thepresynapticneuron.
The receiving neuron is called thepostsynapticneuron.
To stop communication between neurons, there are three processes that can take place.
In a process known asreuptake, the neurotransmitters are reabsorbed by the presynaptic neuron to be reused.
In the case ofdegradation, the neurotransmitters are broken down in the gap by enzymes.
Other neurotransmitters will simplydiffuseaway from the synaptic gap.
Neurotransmitters
Neurotransmittersare an essential part of our everyday functioning.
Excitatory neurotransmitters stimulate nervous system activity while inhibitory neurotransmitters do the opposite and dampen down nervous system activity.
Modulatory neurotransmitters will coordinate the activity of other chemical messengers.
Acetylcholine:Associated with memory, learning, and muscle contractions.
A lack ofacetylcholinein the brain is associated with Alzheimers disease.
The body releasesendorphinsin response to injury, fear, or trauma.
Endorphins are associated with emotions, pain perception, sexual response, and maternal behavior.
Similarities
Differences
Stifani N.Motor neurons and the generation of spinal motor neuron diversity.Front Cell Neurosci.
2014;8. doi:10.3389/fncel.2014.00293
National Institute of Biomedical Imaging and Bioengineering.Neuromuscular junction, hows that function?
Purves D, Augustine GJ, Fitzpatrick D, et al.
Sunderland: Sinauer Associates; 2008.
Ferreira-Vieira TH, Guimaraes IM, Silva FR, Ribeiro FM.Alzheimer’s disease: Targeting the cholinergic system.Curr Neuropharmacol.
2020;22(1):338. doi:10.3390/ijms22010338
Inagaki TK.Opioids and social connection.Curr Dir Psychol Sci.
2019;16(5-6):30-37.
Fuchs E, Flugge G.Adult neuroplasticity: More than 40 years of research.Neural Plasticity.
McGraw Hill; 2021.
