Hamamoto Yumi, Oba Kentaro, Ishibashi Ryo, Ding Yi, Nouchi Rui, Sugiura Motoaki
Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan.
Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom.
Front Psychiatry. 2024 Mar 6;15:1337776. doi: 10.3389/fpsyt.2024.1337776. eCollection 2024.
Body-image disturbance is a major factor in the development of eating disorders, especially among young women. There are two main components: perceptual disturbance, characterized by a discrepancy between perceived and actual body size, and affective disturbance, characterized by a discrepancy between perceived and ideal body size. Interventions targeting body-image disturbance ask individuals to describe their own body without using negative expressions when either viewing it in a mirror or imagining it. Despite the importance of reducing body-image disturbance, its neural mechanisms remain unclear. Here we investigated the changes in neural responses before and after an intervention. We hypothesized that neural responses correlated with the degree of body-image disturbance would also be related to its reduction, i.e., a reduction in perceptual and affective disturbances would be related to changes in attentional and socio-cognitive processing, respectively.
Twenty-eight young adult women without known psychiatric disorders underwent a single 40-min intervention. Participants completed tasks before and after the intervention, in which they estimated their perceived and ideal body sizes using distorted silhouette images to measure body-image disturbance. We analyzed the behavioral and neural responses of participants during the tasks.
The intervention did not significantly reduce body-image disturbance. Analysis of individual differences showed distinct changes in neural responses for each type of disturbance. A decrease in perceptual disturbance was associated with bodily visuospatial processing: increased activation in the left superior parietal lobule, bilateral occipital gyri, and right cuneus. Reduced affective disturbance was associated with socio-cognitive processing; decreased activation in the right temporoparietal junction, and increased functional connectivity between the left extrastriate body area and the right precuneus.
We identified distinct neural mechanisms (bodily visuospatial and socio-cognitive processing) associated with the reduction in each component of body-image disturbance. Our results imply that different neural mechanisms are related to reduced perceptual disturbance and the expression thereof, whereas similar neural mechanisms are related to the reduction and expression of affective disturbance. Considering the small sample size of this study, our results should be regarded as preliminary.
身体意象障碍是饮食失调发展的一个主要因素，尤其是在年轻女性中。它有两个主要组成部分：感知障碍，其特征是感知到的身体大小与实际身体大小之间存在差异；情感障碍，其特征是感知到的身体大小与理想身体大小之间存在差异。针对身体意象障碍的干预措施要求个体在照镜子或想象自己的身体时，不使用负面表达来描述自己的身体。尽管减少身体意象障碍很重要，但其神经机制仍不清楚。在这里，我们研究了干预前后神经反应的变化。我们假设与身体意象障碍程度相关的神经反应也与障碍的减轻有关，即感知障碍和情感障碍的减轻分别与注意力和社会认知加工的变化有关。
28名无已知精神疾病的年轻成年女性接受了一次40分钟的干预。参与者在干预前后完成任务，在任务中他们使用变形的轮廓图像估计自己感知到的和理想的身体大小，以测量身体意象障碍。我们分析了参与者在任务过程中的行为和神经反应。
干预并未显著减少身体意象障碍。个体差异分析显示，每种类型的障碍在神经反应上有明显变化。感知障碍的减少与身体视觉空间加工有关：左侧顶上小叶、双侧枕叶回和右侧楔叶的激活增加。情感障碍的减轻与社会认知加工有关；右侧颞顶联合区的激活减少，左侧纹外体区与右侧楔前叶之间的功能连接增加。
我们确定了与身体意象障碍各组成部分减轻相关的不同神经机制（身体视觉空间和社会认知加工）。我们的结果表明，不同的神经机制与感知障碍的减轻及其表达有关，而相似的神经机制与情感障碍的减轻和表达有关。考虑到本研究的样本量较小，我们的结果应被视为初步结果。
