Inhibitory control, a fundamental component of executive function, refers to the ability to control one’s attention and suppress internal and external interferences effectively to achieve the setting targets. It plays a crucial role in allowing us to adapt to the environment, and serves as a basis of other cognitive functions, such as reasoning, planning and learning. Moreover, several psychiatric disorders, such as addictions, attention deficit hyperactivity and obsessive-compulsive disorder have been shown to involve deficits in inhibitory control. Thus, establishing ways in which inhibitory control can be improved constitutes an important issue for psychologist and medical scientist. In recent years, musical training has been suggested to be associated with improved executive functions, such as inhibitory control. However, the overall findings in these studies have been mixed. While some studies indicated a positive relationship between musical training and inhibitory control, other studies showed no facilitative effect of musical training. Importantly, however, inhibitory control is not a single function, but can be divided into response inhibition and interference control. Previous studies that assessed the relationship between musical training and inhibitory control failed to investigate these two separate components within the same experiment. Furthermore, its underlying neural mechanism remain elusive. Based on these considerations, the present study aimed to examine the relationship between musical training and inhibitory control through the Go/No-go (response inhibition) and Stroop (interference control) tasks by using event- related-potentials (ERPs).
Experiments were carried out in an acoustically and electrically shielded room, and lasted approximately 40 minutes. In the Go/No-go task, participants had to press a keyboard button in response to white shapes (Go trials, 75%), while they had to inhibit responding to purple shapes (No-go trials, 25%). Each stimulus was presented for 500 ms with an interstimulus interval of 1000 ms. The experiment consisted of 320 trials, presented in a random order. Performance was evaluated using a Signal Detection approach by calculating perceptual sensitivity via: d′ = z(No-go hit rate) - z(Go false alarm rate). Higher d’ values indicate better response inhibition. In the Stroop task, participants were presented with Chinese color words (red, green, blue, yellow), printed in different colors. Stimuli were divided into word-color consistent trails (congruent, 50%) and word-color inconsistent trails (incongruent, 50%). A stimulus was presented for 1000 ms with a random interstimulus interval of 1000~1500 ms. Participants had to name the color in which the word was presented without paying attention to the word’s meaning. The experiment consisted of 240 trials, presented in a random order. The difference between accuracy in the congruent and the incongruent conditions is referred to as Stroop interference effect. Smaller effects are indicative of better interference control. The experimental sequence was balanced between participants.
The behavioral results showed that music group had smaller interference effect than the control group in the Stroop task, while both groups performed similarly in the Go/No-go task. As for the ERP results, in Go/No-go task, the amplitudes of the N2 (N2d) and P3 difference waves, contrasting No-go and Go trials, were larger in music group than in control group. In the Stroop task, the amplitude of the N450 (N450d) difference wave, contrasting congruent and incongruent trials, were also larger in music group than in control group. However, the amplitude of the SP (SPd) difference wave, which serves as an index of conflict resolution, was similar between the two groups.
The aim of present study was to explore the influence of music training on the cognitive and neural mechanisms governing inhibitory control. The present results supported the hypothesis that individuals that received music training had stronger conflict monitoring and motor inhibition abilities when completing the response inhibition task, as well as a better conflict monitoring ability when completing the interference control task. This indicates a potential association between music training and inhibitory control.
