Introduction to Neuroanatomy and Neurophysiology

Abstract

This article covers basic concepts in neuroanatomy and neurophysiology related to the topic of neurodevelopment and associated disorders. Initially, the article introduces the fundamental cells of the nervous system, i.e., neurons and neuroglia. The types of neuroglia are differentiated according to their function, while the structures of neurons (cell body, dendrite, axon and axon terminals) are presented. The electrochemical processes of neuronal transmission are discussed, from changes in the resting membrane potential to the generation of the action potential and eventual synaptic propagation of the signal. Synapses and the main neurotransmitters of the nervous system are also presented. The nervous system as a whole is divided and analyzed, including its central and peripheral portions, and, more specifically, its subdivisions into cerebrum, cerebellum and brainstem and somatic, autonomic/visceral and enteric nervous systems, respectively. The spinal cord and its spinal and cranial nerves are also shown as part of the peripheral nervous system, as are the major ascending (dorsal-medial lemniscus and lateral spinothalamic) and descending (lateral corticospinal) pathways and their sensory and motor functions. A table was constructed to summarize the functions of the twelve cranial nerves. A second table helps to illustrate the different functions of the sympathetic (fight-or-flight) and parasympathetic (rest-and-digest) nervous system, subdivisions of the autonomic nervous system. Finally, the concept of neuroplasticity is briefly discussed, considering its importance for neurodevelopment.