👉 Sexagenary is a concept in psychology that refers to the stages of development, which are divided into two phases. The first phase, known as the prefrontal stage or early frontal lobe stage, is characterized by the presence of the primary motor cortex and the formation of the basic motor skills. This period lasts from birth until about 2 years old. The second phase, also known as the secondary motor cortex stage, begins around 3 to 4 years of age and continues until adolescence
