Dominance of Attention Focus and Its Electroencephalogram Activity in Standing Postural Control in Healthy Young Adults

Dominance of attentional focus: a comparative study on its impact on standing postural control in healthy younger and older adults

Introduction

Attentional focus is a phenomenon in which shifting the focus of attention alters performance of standing postural control. It can be categorized as internal focus (IF), which directs attention to the body parts, or external focus (EF), which directs attention to the external environment. Although attentional focus that improves standing postural control in younger people exhibits individual dominance, the dominance of attentional focus in standing postural control in older adults remains ambiguous. Therefore, this study aimed to compare the dominance of attentional focus in standing postural control between healthy younger and older adults, a crucial step for understanding the aging process.

Methods

The participants performed a standing postural control task under the IF and EF conditions. Based on the condition during which they exhibited superior performance, the participants were divided into two groups: IF-dominant and EF-dominant. The standing postural control performance in each group under the IF and EF conditions was subsequently compared.

Results

The results showed that the participants, encompassing both younger and older adults, were divided into the IF-dominant and EF-dominant groups, confirming the dominance of attentional focus. The performance under the EF condition in older adults was also influenced by the dominance of attentional focus.

Conclusion

These results highlight the potential importance of intervention methods based on the dominance of attentional focus, providing valuable insights into future research and clinical practice.

Effects of θ High Definition-Transcranial Alternating Current Stimulation in the Anterior Cingulate Cortex on the Dominance of Attention Focus in Standing Postural Control

Attention focus affects performance in postural control while standing, and it is divided into internal focus (IF) and external focus (EF). Each individual has a predominant attention focus, and research has revealed that the dominance of attention focus may be an acquired trait. However, the impact of non-invasive brain stimulation on attention-focus dominance remains unexplored in the current literature. Here, we examined the effect of high-definition transcranial alternating current stimulation (HD-tACS) on θ waves in the anterior cingulate cortex (ACC) on standing postural control tasks in an EF condition for IF- and EF-dominant groups. The effect of θ HD-tACS on the ACC differed between IF- and EF-dominant groups, and θ HD-tACS in the IF-dominant group decreased the performance of standing postural control under the EF condition. The forced activation of the ACC with θ HD-tACS may have conversely reduced the activity of brain regions normally activated by the IF-dominant group. Additionally, the activation of ACC prioritized visual information processing and suppressed the superficial sensory processing that is normally potentially prioritized by the IF-dominant group. These results highlight the importance of changing the type of rehabilitation and sports training tasks to account for the individual's dominance of attention focus.

The order of attentional focus instructions affects how postural control processes compensate for multisensory mismatch: a crossover study

Directing attention during balance training can have an immediate and lasting impact on a patient's balance and ultimately decrease the risk of future falls. However, it is unclear how attention can best be utilized to improve postural control. The current study uses a 2 × 2 crossover design to investigate the potential impact of receiving multiple verbal instructions during a single session of sensorimotor control testing for balance. Twenty-eight healthy adults were tasked to balance on a rocker board while immersed in virtual reality (VR). The VR created a multisensory mismatch between visual VR motion and body motion. The strength of the relationship between visual motion and body motion was measured to assess visual dependence. Alpha and theta frequency bands in electroencephalography (EEG) recordings were also analyzed to identify potential neural correlates of visual dependence and postural stability. Participants were randomized into two groups: one group was first instructed to keep the board leveled (external focus) and then instructed to keep both feet leveled (internal focus) to help maintain stability. The other group was given these two instructions in reverse order. Analyses focused on time, instruction, and group effects from receiving multiple instructions. Results revealed that when participants are given external focus first, and internal focus second, they are more likely to demonstrate lower visual dependence and better postural stability throughout the entire session than participants given internal focus first and external focus second. However, channel-level EEG analyses did not reveal differences between the groups. Current findings suggest that the order of attentional focus instructions may influence how the postural control system resolves sensory incongruence during a single testing session.