The traits of five types of tongue movement in Han of Shaanxi, China

The study sample consisting of 429 people (207 males, 222 females) of Han nationality in Shaanxi, China. Five types of tongue movements were investigated, including tongue rolling, tongue folding, tongue twisting, pointed tongue and clover-leaf tongue. The results revealed that the frequencies of tongue rolling, tongue folding, tongue twisting, pointed tongue and clover-leaf tongue were 63.6, 14.0, 12.6, 54.8 and 0 %, respectively. There were no significant gender differences except with pointed tongue. Compared with other nationalities, tongue rolling, tongue folding, and pointed tongue of Han in Shaanxi had an average frequency. Tongue twisting and clover-leaf tongue had low frequencies. There were significant differences in frequency of clover-leaf tongue between Han and another seven nationalities of China (P < 0.01). Furthermore, only three pairs of trait correlations were exhibited among ten pairs of types of tongue movement combination traits when analyzed using Pearson’s correlation coefficient. The data indicated that the correlations of tongue movement were between tongue rolling and tongue folding, between pointed tongue and tongue rolling, and also between tongue folding and pointed tongue, respectively. Additionally, there were significant differences in frequency of tongue movements with age. The possible mechanism of variations of tongue movements with aging may involve the degradation of tongue function, and differential gene activation and modulation, or protein translation.