Manual dexterity

Fine motor skill (or dexterity) is the coordination of small muscles, in movements—usually involving the synchronization of hands and fingers—with the eyes. The complex levels of manual dexterity that humans exhibit can be attributed to and demonstrated in tasks controlled by the nervous system. Fine motor skills aid in the growth of intelligence and develop continuously throughout the stages of human development.

Motor skills are movements and actions of the muscles. Typically, they are categorized into two groups: gross motor skills and fine motor skills. Gross motor skills are involved in movement and coordination of the arms, legs, and other large body parts and movements. They participate in actions such as running, crawling, swimming, etc. Fine motor skills are involved in smaller movements that occur in the wrists, hands, fingers, and the feet and toes. They participate in smaller actions such as picking up objects between the thumb and finger, writing carefully, and even blinking. These two motor skills work together to provide coordination. The index is usually the most dexterous and sensitive finger of the hand.

Through each developmental stage of a child’s life and throughout our lifetime motor skills gradually develop. They are first seen during a child’s development stages: infancy, toddlerhood, preschool and school age. "Basic” fine motor skills gradually develop and are typically mastered between the ages of 6-12 in children. These skills will keep developing with age, practice and the increased use of muscles while playing sports, playing an instrument, using the computer, and writing. If deemed necessary, occupational therapy can help improve overall fine motor skills.

The first motor skills, beginning from birth, are initially characterized by involuntary reflexes. The most notable involuntary reflex is the Darwinian reflex, a primitive reflex displayed in various newborn primates species. These involuntary muscle movements are temporary and often disappear after the first two months. After eight weeks, the infant will begin to voluntarily use their fingers to touch. However, their ability to grab objects is still undeveloped at this point.

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Wikipedia