Laboratory of Medical Informatics (LIM 01), Faculty of Medicine of the University of São Paulo, São Paulo, Brazil.
PLoS One. 2011;6(12):e28752. doi: 10.1371/journal.pone.0028752. Epub 2011 Dec 14.
In medical practice, diagnostic hypotheses are often made by physicians in the first moments of contact with patients; sometimes even before they report their symptoms. We propose that generation of diagnostic hypotheses in this context is the result of cognitive processes subserved by brain mechanisms that are similar to those involved in naming objects or concepts in everyday life.
To test this proposal we developed an experimental paradigm with functional magnetic resonance imaging (fMRI) using radiological diagnosis as a model. Twenty-five radiologists diagnosed lesions in chest X-ray images and named non-medical targets (animals) embedded in chest X-ray images while being scanned in a fMRI session. Images were presented for 1.5 seconds; response times (RTs) and the ensuing cortical activations were assessed. The mean response time for diagnosing lesions was 1.33 (SD ±0.14) seconds and 1.23 (SD ±0.13) seconds for naming animals. 72% of the radiologists reported cogitating differential diagnoses during trials (3.5 seconds). The overall pattern of cortical activations was remarkably similar for both types of targets. However, within the neural systems shared by both stimuli, activation was significantly greater in left inferior frontal sulcus and posterior cingulate cortex for lesions relative to animals.
Generation of diagnostic hypotheses and differential diagnoses made through the immediate visual recognition of clinical signs can be a fast and automatic process. The co-localization of significant brain activation for lesions and animals suggests that generating diagnostic hypotheses for lesions and naming animals are served by the same neuronal systems. Nevertheless, diagnosing lesions was cognitively more demanding and associated with more activation in higher order cortical areas. These results support the hypothesis that medical diagnoses based on prompt visual recognition of clinical signs and naming in everyday life are supported by similar brain systems.
在医疗实践中，诊断假设通常是医生在与患者接触的最初时刻做出的；有时甚至在他们报告症状之前。我们提出，在这种情况下生成诊断假设是由大脑机制支持的认知过程的结果，这些机制与日常生活中命名物体或概念所涉及的机制相似。
为了验证这一假设，我们开发了一种使用功能磁共振成像 (fMRI) 的实验范式，以放射诊断为模型。 25 名放射科医生在 fMRI 扫描过程中诊断胸部 X 光图像中的病变，并命名嵌入胸部 X 光图像中的非医学目标（动物）。图像呈现 1.5 秒；评估反应时间 (RT) 和随后的皮质激活。诊断病变的平均反应时间为 1.33 秒（SD ± 0.14），命名动物的反应时间为 1.23 秒（SD ± 0.13）。 72%的放射科医生在试验期间（3.5 秒）报告了对鉴别诊断的思考。两种类型的目标的皮质激活总体模式非常相似。然而，在两种刺激共有的神经系统中，左侧额下回和后扣带回的激活明显大于动物。
通过对临床体征的直接视觉识别生成诊断假设和鉴别诊断可以是一个快速和自动的过程。病变和动物的显著大脑激活的共定位表明，病变的诊断假设和动物的命名是由相同的神经元系统提供的。然而，诊断病变在认知上更具挑战性，与高级皮质区域的更多激活相关。这些结果支持这样的假设，即基于对临床体征的快速视觉识别和日常生活中的命名的医学诊断是由相似的大脑系统支持的。
