The extension of cell theory to nervous system by Santiago Ramon y Cajal (1832-1934) following Heinrich Waldeyer. It has two main theses, which form the basis of modern neuroscience: 1. the nervous system is composed of discrete units or cells, called neurons, that are both structurally and functionally discrete in having their own membranes and functioning …
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Neuromuscular junction
An area of membrane between a motoneuron and the membrane plasma of a muscle (i.e., the motor end plate) that forms a synapse between them that ramifies into a number of fine branches with terminal swellings called synaptic boutons. The boutons lie over the motor end plates, and they are separated by a synaptic cleft. …
Neuron
A nerve cell, consisting of cell body or soma and processes, that collects incoming or afferent information (via the dendrites), and transports outgoing or efferent information (via the axon). Thehuman brain has some 100 billion neurons in many different sizes and shapesdepending on their respective functions, with the smallest neurons having cellbodies just 4 microns …
Neuromaturational theories
Theories supposedly holding the view that development is determined solely by the genetic regulation of maturational processes. On closer inspection, no such monocausal theories exist since at least the end of the 19th century, at least in embryology. See Neural determinism, Neuromaturation, Radical behaviorism (or environmentalism)
Neurology
A branch of medicine dealing with the anatomy, physiology, and organic diseases of the central and peripheral nervous systems. According to Charles Sherrington (1857-1952), Thomas Willis (1621-1675), who first came up with the term ‘neurology’ and who gave his name the arterial circle at the base of the brain, should be considered as the founder …
Neuromaturation
The genetically-determined process by which the nervous system becomes mature, and a relatively vacuous concept. See Determinism, Genetic determinism, Neural determinism, Neuromaturational theories, Predetermined epigenesis
Neurological ‘soft’ signs
Minor versions of signs seen in some acquired motor disorders or severe neurodevelopment syndromes (e.g., developmental coordination disorder). See Developmental coordination disorder (DCD), Developmental disorders, Minor neurological dysfunction (MND), Neurodevelopmental disorder, Signs and symptoms
Neuroimaging studies
Studies of the brain that allow scientists to see the structure and workings of the brain during mental or motor tasks, and which helps to understand their localisation, sequencing and network interactions. Includes, for example, PET (positron emission tomography), fMRI (functional magnetic resonance imaging), ERPs (event-related potentials), and MEG (magnetoencephalography). See Brain (neuro-) imaging, Diffusion magnetic …
Neurogenesis
Proliferation of neurons in early development by division of precursor cells, and in which larger motoneurons are established before smaller sensory neurons. Neurogenesis is essentially complete in most parts of the brain by 30 weeks gestation in the human, but with some exceptions such as the cerebellum, dentate gyrus, and hippocampus. Following an ‘inside-out, outside-last’ pattern …
Neurodevelopmental disorder
A disorder of development associated with dysfunctioning of the central nervous system. See Developmental coordination disorder (DCD), Developmental disorders, Minor neurological dysfunction (MND), Neurological ‘soft’ disorders