Consist of several intertwining loops among the basal ganglia nuclei & thalamic nuclei Striatum (caudate & putamen) is receiver of input to basal ganglia Frontal cortex especially premotor area
Each strand of hair on the human body is at its own stage of development. Once the cycle is complete, it restarts and a new strand of hair begins to form. The rate or speed of hair growth is about 1.25 centimetres or 0.5 inches per month, or about 15 centimetres or 6 inches per year.
The most oft-quoted average rate of human hair growth is 6 inches (15 centimeters) per year. However, the majority of studies measuring the rate of hair growth didn't take into account the race of study participants. 2005 study in the International Journal of Dermatology also found a difference among races in the rate of hair growth. For example, Asian hair grows the fastest, while African hair grows the slowest. The average hair growth rate of Asian female participants was nearly 6 inches per year.