The flattened contact site, or neuromuscular junction, between a nerve cell and a striated muscle fiber, with each fiber forming one end plate. Also known as a motor plate, It synapses with the bouton of a motoneuron and is in essence a modification of the overlying sacrolemma, with which it is continuous (the sarcolemma being …
Author Archives: Brian Hopkins
Motor equivalence
Based on the biological concept of equifinality (i.e., employing different means to achieve the same end state), it can be defined as performing an action or a task in a variety of different ways. To put it another way, it involves using movements in a flexible manner so as to achieve a particular outcome such …
Motor development
Starting early in prenatal life, progressive, and sometimes regressive, changes in recognizable movement and postural patterns from simple to more complex forms of organization, associated with growth, maturation and experience. Theoretically, the study of motor development, largely through the application of dynamical systems thinking starting in the 1990s, involves a number of issues such the how …
Motor control
The control of the kinematics and dynamics (i.e., force) of movements by the brain that involves the regulation of the positions and motions of the various parts of the body in relation to each other and to one or more external frames of reference in order to achieve a particular goal. More technically, it is …
Motor cortex
The part of the cerebral cortex, including the primary motor cortex and adjacent areas of the frontal lobe, that generates commands for movement, connected directly to the motoneurons of the spinal cord as well as indirectly to other so-called motor structures such as the basal ganglia and the cerebellum via the thalamus (see figure below). …
Motor ability
The qualities, power, competence, faculties, proficiencies, dexterities, talents, etc., that enable one to perform a particular motor feat at a specified time. It is a theoretical construct regarding factors that underlie proficiency in motor tasks (e.g., strength, speed, power, agility, balance, coordination, flexibility, accuracy, endurance). The factors are ordinarily measured with standardized tests (e.g., vertical …
Motoneuron
A nerve cell (i.e., spinal motoneuron) innervating a muscle. Thus, it is an efferent neuron that originates in the spinal cord and synapses with muscle fibers to facilitate muscle contraction and with muscle spindles to modify proprioceptive sensitivity. Motoneurons in both the somatic and autonomic nervous system (ANS) originate in the ventral gray column of …
Motion perception
The ability to discriminate between different directions and speeds of motion of visual stimuli, as well as those provided by proprioceptive and vestibular inputs. The visual system infers motion from changing patterns of light in the retinal image, but something that has proved difficult to explain in terms of neural mechanisms and processes, or by …
Motion parallax
The relative motions of individual objects viewed as an observer moves, as in looking at trees in a forest when driving past. Thus, objects closer to you move further across your field of vision than those at a distance. It is one of the monocular cues for depth perception. Animals without binocular vision (i.e., without …
Motility
The ability to move spontaneously, used particularly with reference to independent cell locomotion (e.g., by spermatozoa) and the first movements of the embryo. The latter are generated by spontaneous activity in the central nervous system and are not related to a specific task or goal. See Cell locomotion, Central pattern generator (CPG), Embryo, Movement, Peristaltic, …