Brain Plasticity Induced by Musical Expertise on Proactive and Reactive Cognitive Functions

Media multitasking enhances individuals' anticipatory brain functions

Media multitasking has become pervasive in our daily lives, yet its impact on cognitive abilities remains contentious, with more evidence supporting adverse effects (scattered attention hypothesis) than benefits (trained attention hypothesis). Recent studies have increasingly focused on the training effects of behavioral training on anticipatory brain functions, which involve cognitive and motor preparation before stimulus onset, assessed using event-related potentials (ERPs). This study investigated whether media multitasking enhances anticipatory brain functions and how task difficulty influences this relationship. Participants performed a response discrimination task where they detected targets among distractors, with salient and nonsalient targets manipulating task difficulty. Behavioral results indicated faster response times and comparable accuracy in heavy media multitaskers (HMM) compared to light media multitaskers (LMM) across both salient and nonsalient conditions, suggesting that media multitasking can expedite responses without sacrificing accuracy. The larger Bereitschaftspotential (BP) amplitude observed in HMM compared to LMM reflects heightened motor preparation in HMM, consistent with their quicker responses. The larger prefrontal negativity (pN) and P3 amplitudes in the nonsalient condition for HMM indicate increased cognitive preparation before stimulus onset and heightened attention control after stimulus onset. Our results suggest that HMM can flexibly adjust resource allocation based on task demands to maintain their response speed advantage. These findings suggest that LMM may possess a relatively steady acceleration/brake system, whereas HMM exhibit a more adaptable system capable of responding flexibly to diverse situations. Overall, these results underscore the training effects of media multitasking on anticipatory brain functions, supporting the trained attention hypothesis.

Visually Perceived Negative Emotion Enhances Mismatch Negativity but Fails to Compensate for Age-Related Impairments

Objective: Automatic detection of auditory stimuli, represented by the mismatch negativity (MMN), facilitates rapid processing of salient stimuli in the environment. The amplitude of MMN declines with ageing. However, whether automatic detection of auditory stimuli is affected by visually perceived negative emotions with normal ageing remains unclear. We aimed to evaluate how fearful facial expressions affect the MMN amplitude under ageing.

Methods: We used a modified oddball paradigm to analyze the amplitude of N100 (N1) and MMN in 22 young adults and 21 middle-aged adults.

Results: We found that the amplitude of N1 elicited by standard tones was smaller under fearful facial expressions than neutral facial expressions and was more negative for young adults than middle-aged adults. The MMN amplitude under fearful facial expressions was greater than neutral facial expressions, but the amplitude in middle-aged adults was smaller than in young adults.

Conclusion: Visually perceived negative emotion promotes the extraction of auditory features. Additionally, it enhances the effect of auditory change detection in middle-aged adults but fails to compensate for this decline with normal ageing.

Significance: The study may help to understand how visually perceived emotion affects the early stage of auditory information processing from an event process perspective.