Haupt Marleen, Graumann Monika, Teng Santani, Kaltenbach Carina, Cichy Radoslaw
Department of Education and Psychology, Freie Universität Berlin, Berlin, Germany.
Berlin School of Mind and Brain, Faculty of Philosophy, Humboldt-Universität zu Berlin, Berlin, Germany.
Elife. 2024 Dec 4;13:RP98148. doi: 10.7554/eLife.98148.
Experience-based plasticity of the human cortex mediates the influence of individual experience on cognition and behavior. The complete loss of a sensory modality is among the most extreme such experiences. Investigating such a selective, yet extreme change in experience allows for the characterization of experience-based plasticity at its boundaries. Here, we investigated information processing in individuals who lost vision at birth or early in life by probing the processing of braille letter information. We characterized the transformation of braille letter information from sensory representations depending on the reading hand to perceptual representations that are independent of the reading hand. Using a multivariate analysis framework in combination with functional magnetic resonance imaging (fMRI), electroencephalography (EEG), and behavioral assessment, we tracked cortical braille representations in space and time, and probed their behavioral relevance. We located sensory representations in tactile processing areas and perceptual representations in sighted reading areas, with the lateral occipital complex as a connecting 'hinge' region. This elucidates the plasticity of the visually deprived brain in terms of information processing. Regarding information processing in time, we found that sensory representations emerge before perceptual representations. This indicates that even extreme cases of brain plasticity adhere to a common temporal scheme in the progression from sensory to perceptual transformations. Ascertaining behavioral relevance through perceived similarity ratings, we found that perceptual representations in sighted reading areas, but not sensory representations in tactile processing areas are suitably formatted to guide behavior. Together, our results reveal a nuanced picture of both the potentials and limits of experience-dependent plasticity in the visually deprived brain.
基于经验的人类皮质可塑性介导个体经验对认知和行为的影响。一种感觉模态的完全丧失是此类最为极端的经验之一。研究这种选择性但极端的经验变化，有助于在其边界处表征基于经验的可塑性。在此，我们通过探测盲文字母信息的处理过程，研究了出生时或生命早期失明个体的信息处理情况。我们表征了盲文字母信息从依赖阅读手的感觉表征到独立于阅读手的知觉表征的转变。我们使用多变量分析框架，结合功能磁共振成像（fMRI）、脑电图（EEG）和行为评估，在空间和时间上追踪皮质盲文表征，并探究它们与行为的相关性。我们在触觉处理区域定位了感觉表征，在视力正常者的阅读区域定位了知觉表征，外侧枕叶复合体作为连接的“枢纽”区域。这从信息处理方面阐明了视觉剥夺大脑的可塑性。在时间上的信息处理方面，我们发现感觉表征先于知觉表征出现。这表明，即使是大脑可塑性的极端情况，在从感觉转变为知觉的过程中也遵循一种共同的时间模式。通过感知相似性评分确定行为相关性，我们发现视力正常者阅读区域的知觉表征，而非触觉处理区域的感觉表征，经过适当格式化以指导行为。总之，我们的研究结果揭示了视觉剥夺大脑中依赖经验的可塑性的潜力和局限性的细微情况。
