The effects of different challenge-level balance tasks on stroke cortical responses and balance assessment using EEG

Useless! You didn't write a protocol on this!

(I thought the Berg Balance Scale testing that was common, was totally worthless since there never was any specific therapy given to address the failure points I had in that test. There is really no point in measuring something if you have nothing that will improve your ability for the next test.)

 The effects of different challenge-level balance tasks on stroke cortical responses and balance assessment using EEG

Rui Xu et al.: The Effects of Different Challenge-Level Balance Tasks on Stroke Cortical Responses and Balance Assessment
1

Abstract

—Previous studies have validated that different
balance tasks induce different cortical responses, which
are key indexes of balance assessment. Assessing balance
is crucial for stroke survivors to prevent falls and improve
rehabilitation outcomes. However, it was unclear whether
these tasks may affect the balance assessment, particularly
regarding the relationship between task difficulty and the
corresponding cortical responses involved in balance
control. Therefore, we sought to explore the effects of
different challenge-level balance tasks on balance
assessment. Eighteen participants with stroke and thirteen
healthy individuals were recruited in this study. The EEG
was collected during sitting, standing and perturbation
tasks. The pairwise-derived Brain Symmetry Index (pdBSI),
and Granger Causality (GC) were analyzed with a two-way
(task ×group) RMANOVA. Finally, a multiple linear
regression analysis was applied to predict the BBS score
with the above parameters. We found a significant
interaction effect on pdBSI and GC. In the frontal lobe,
participants with stroke exhibited significantly higher
pdBSI (standing: p=0.042, perturbation: p=0.013) and lower
GC (standing: p<0.001, perturbation: p=0.028) compared to
healthy controls. Similarly, in the parietal lobe, stroke
survivors showed markedly higher pdBSI (standing: p =
0.006, perturbation: p=0.012) and lower GC (standing:
p=0.030, perturbation: p=0.011). Finally, The Berg Balance
Scale (BBS) scores could be reliably predicted using
parietal BSI and frontal GC metrics recorded during
standing (p<0.001, adjusted R²=0.938) and perturbation
tasks (p=0.001, adjusted R²=0.644). It was discovered that
the more challenging balance tasks better revealed the
difference in the power distribution and the directional
functional connection between groups. The pdBSI and GC
during standing and perturbation tasks, could be used as
biomarkers for stroke balance assessment.
Index Terms—Balance assessment, Brain symmetry,
Granger Causality, Stroke, Balance task
# These authors contributed equally to this work.
*Corresponding author: Lin Meng, linmeng@tju.edu.cn; Jun Liang,
15122878711@163.com.
From the a: Academy of Medical Engineering and Translational Medicine,
Tianjin University, Tianjin 300072, China; b: Department of Rehabilitation,
Tianjin Medical University General Hospital, Tianjin 301700, China; c:
Xiangyu Medical, Henan 456300, China.
.
I. Introduction
troke is a neurological disease characterized by the
blockage or rupture of blood vessels, posing a serious threat
to human life and health [1]. Between 1990 and 2019, there was
a substantial increase in the burden of stroke[2], with a 70% rise
in incident strokes, a 43% increase in stroke-related deaths, 102%
increase in prevalent strokes, and 143% increase in disability-
adjusted life-years (DALYs) [2]. Lower-limb motor
dysfunction affects nearly 80% of stroke survivors [3]. Balance
is essential for maintaining postures, performing daily activities,
and responding to external disturbances [4]. The reduced
balance ability in stroke survivors raises the risk of fall injuries,
which can result in bone fractures, head injuries, and a fear of
falling [5]. These injuries have a negative impact on their
rehabilitation. Several studies have indicated a correlation
between balance ability and quality of life. Additionally, the
fear of falling can reduce a patient's enthusiasm for engaging in
social activities [6, 7]. Therefore, balance rehabilitation is of
utmost importance for people with stroke to regain their
independence[8].
Effective balance rehabilitation requires a thorough
assessment of balance function to guide training and prevent
falls[9]. (THEN WHERE IS THE EXACT PROTOCOL FOR RECOVERY?)

The Berg Balance Scale (BBS) is commonly used to

evaluate(Evaluation does nothing to get you recovered!) 

the balance function of patients with brain injuries. It
assesses the patient's ability to transfer their active center of
gravity in various functional activities [10]. To obtain BBS
scores, a comprehensive examination of the patient's dynamic
and static balance in sitting and standing positions was
conducted. A study involving 655 physical therapists identified
the BBS as the most commonly used assessment tool in stroke
rehabilitation [11]. Therefore, the scale method is widely
accepted due to its validity and reliability. However, the scale
does have a ceiling effect and some subjectivity, as it may not
accurately capture subtle improvements in higher-functioning
stroke survivors. This limitation highlights the need for
supplementary objective measures [12]. This highlights the
need for the development of objective assessment methods.
According to the mechanism of human balance control system,
the cerebral cortex plays a key role in balance control,
integrating and processing information from various receptors
[13]. Thus, balance control is closely related to cortical
activities. Techniques like electroencephalography (EEG) offer the potential for more objective biomarkers to detect balance deficits in stroke survivors, as EEG provides real-time cortical

responses to relevant events and can be effectively integrated

with behavioral data.

More at link.