Analysis of Cortical Hemodynamic Responses in the Prefrontal Lobe during Chopsticks Usage

Abstract

Fine motor skills, such as manipulating utensils, are found to be associated with increased brain activation in the prefrontal cortex (PFC). Limited previous research has examined PFC activation during chopsticks usage as compared to other fine motor tasks requiring a reliable hand‐eye coordination for object manipulations. The purpose of this study was to investigate the cortical hemodynamic responses in the PFC to chopsticks usage versus fork and hand use. Brain responses to chopsticks usage were further compared based on three subgroups categorized by performance proficiency, usage frequency, and chopsticks‐using cultural background. A total of 32 young adults (age 24.4 ± 2.36) participated in this cross‐sectional study and were instructed to transfer kidney beans from a source to a target plate at a comfortable pace using their dominant‐side hand. All participants completed the same task using 3 conditions: chopsticks, fork, and hand in a randomized order. A non‐invasive neuroimaging device, a functional near‐infrared spectroscopy (fNIRS) with 20‐channel configuration at the sampling rate of 7.81 Hz, was used to analyze and compare cortical hemodynamic responses by measuring oxyhemoglobin (HbO2) in the PFC among the three conditions. A repeated‐measures ANOVA revealed a significant difference between chopsticks and hand usage (p< 0.011). Chopsticks use resulted in a 36% greater increase of HbO2 when compared to hand use. However, there was no statistically significant difference between chopsticks and fork use. Subgroup analysis showed a systematic trend of showing decreased brain activation with lower HbO2 in the PFC when participants had better proficiency in using chopsticks, used chopstick more frequently, and had chopsticks‐using cultural background. Our results suggest that the use of chopsticks can increase brain activation in the PFC compared to fork or hand use. The findings also indicate that the brain activity during chopsticks usage can be influenced by other factors, such as a level of proficiency, frequency of use, and cultural background.