“弯曲”行走和深度相机检测早期认知衰退
Mahmoud Seifallahi (seated) and Behnaz Ghoraani, Ph.D., review the performance of straight walking using a depth camera, which can detect and track 25 joints of body movement.
一项史无前例的研究表明，在认知能力下降的早期阶段，老年人通常会发现细微的步态障碍, “throw them a curve.”
Gait analysis, examining the way an individual stands and walks, is emerging as a valuable, 非侵入性补充认知评估，有助于早期诊断和管理. 在临床环境中，步态和平衡测试通常侧重于直线行走路径.
这项新研究冒险进入了一个不同的领域——曲线路径行走——一种更自然但更复杂的活动. Straight walking is a rhythmic and simpler activity, 然而，在弯曲的道路上行走需要更高的认知和运动技能，比如改变方向和保持平衡的过渡时间.
College of Engineering and Computer Science researchers at Florida Atlantic University 是第一个定量比较健康老年人与轻度认知障碍(MCI)老年人在直线和曲线行走中的表现的研究. 轻度认知障碍是认知能力下降的早期阶段患有轻度认知障碍的人过渡到阿尔茨海默病(AD)的风险要高得多.
For the study, researchers used a depth camera, which can detect and track 25 joints of body movement, 记录研究参与者在进行两种不同的步行测试(直线和曲线)时的步态. 对来自25个身体关节的信号进行处理，为每个测试提取50个步态标记, 并采用描述性统计分析对两组的指标进行比较.
Results, published in the Journal of Alzheimer’s Disease Reports, Volume 8, Issue 1, 曲线行走给轻度认知损伤组带来了更大的挑战，并且在检测轻度认知损伤方面优于直线行走. Furthermore, 几项步态指标显示健康对照组和轻度认知损伤患者之间存在显著差异.
步态标记包括两个宏观标记(平均速度和节奏)。, 24个微时间标记(步态周期各亚阶段的足部持续时间), such as stance, swing, step and stride phases), 微空间标记(步态周期各子阶段足部位置变化)和6个微时空标记(步态周期各子阶段足部速度). 这些标记提供了参与者在步态测试中功能表现的详细信息.
研究结果显示，当步行测试从直线行走变为曲线行走时，MCI组的50个步态指标中有31个(62%)比健康对照组的老年人更大, 13项指标在两个研究组之间显示出显著差异.
“Intriguingly, 曲线行走说明了我们研究小组之间的显著差异, even for these macro gait markers. MCI组在曲线行走中表现出明显较低的平均步长和速度, coupled with higher variability across most micro-gait markers,” said Behnaz Ghoraani, Ph.D., senior author, an associate professor, FAU Department of Electrical Engineering and Computer Science , co-director of the FAU Center for SMART Health, 复旦大学传感与嵌入式网络系统工程研究所研究员(I-SENSE), and a fellow of the FAU Stiles-Nicholson Brain Institute. “轻度认知障碍组在弯曲行走时，步幅和步幅的对称性和规律性都有所下降. They also required extended double support time in various areas, especially while changing directions, which resulted in reduced step speed.”
研究结果显示，两组在年龄和性别分布上没有任何显著差异. However, 两组在身体质量指数(BMI)上有显著差异。, years of education and Geriatric Depression Scale (GDS) scores. Participants with MCI had a higher BMI, 受教育程度较低，GDS得分高于健康老年人.
“轻度认知障碍可能是阿尔茨海默病和其他类型痴呆症的早期征兆,” said Ghoraani. “我们的综合方法增强了对步态特征的理解，并表明弯曲路径行走可能更敏感地检测轻度认知痴呆, 哪些可以补充认知评估并有助于早期诊断和治疗.”
阿尔茨海默病通常表现为认知功能下降，个人进行日常活动(如行走)的能力逐渐下降. Accurate and early clinical detection of AD remains a challenge. Typical clinical evaluations include a detailed history, comprehensive physical and neurological examination, cognitive testing, blood work and brain imaging. However, depending on the clinical setting, these methods can be time-consuming, costly and outside some clinicians’ comfort level.
这项研究填补了这一空白，使用一种新的系统来记录老年人的步态, low-cost, non-wearable and easy-setting depth camera, 哪一步是加强病人护理和干预策略的关键.
“这些步态标记提供了一个有希望的潜力，作为认知障碍的早期指标，为这一领域的广泛研究奠定了基础,” said Stella Batalama, Ph.D., dean, FAU College of Engineering and Computer Science. “这项研究的影响还扩展到临床实践，提供了改进的筛查和监测方法，可以在临床环境中以最小的成本和时间轻松复制.”
Study co-authors are Mahmoud Seifallahi, a doctoral student in FAU’s Department of Electrical Engineering and Computer Science; and James E. Galvin, M.D., M.P.H., professor of neurology, chief, Division of Cognitive Neurology, 也是脑健康综合中心和路易体痴呆卓越研究中心的主任, University of Miami Miller School of Medicine.
这项研究的数据分析得到了授予Ghoraani的国家科学基金会的支持.
-FAU-
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