Hsiao Steven
Department of Neuroscience and the Krieger Mind/Brain Institute, The Johns Hopkins University, 338 Krieger Hall, Baltimore, MD 21218, United States.
Curr Opin Neurobiol. 2008 Aug;18(4):418-24. doi: 10.1016/j.conb.2008.09.001. Epub 2008 Oct 6.
Studies show that while the cortical mechanisms of two-dimensional (2D) form and motion processing are similar in touch and vision, the mechanisms of three-dimensional (3D) shape processing are different. 2D form and motion are processed in areas 3b and 1 of SI cortex by neurons with receptive fields (RFs) composed of excitatory and inhibitory subregions. 3D shape is processed in area 2 and SII and relies on the integration of cutaneous and proprioceptive inputs. The RFs of SII neurons vary in size and shape with heterogeneous structures consisting of orientation-tuned fingerpads mixed with untuned excitatory or inhibitory fingerpads. Furthermore, the sensitivity of the neurons to cutaneous inputs changes with hand conformation. We hypothesize that these RFs are the kernels underlying tactile object recognition.
研究表明，虽然二维（2D）形状和运动处理的皮质机制在触觉和视觉中相似，但三维（3D）形状处理的机制却有所不同。二维形状和运动在初级体感皮层（SI）的3b区和1区由具有由兴奋性和抑制性子区域组成的感受野（RF）的神经元进行处理。三维形状在2区和次级体感皮层（SII）进行处理，并依赖于皮肤感觉和本体感觉输入的整合。SII神经元的感受野大小和形状各异，其异质结构由定向调谐的指腹与非调谐的兴奋性或抑制性指腹混合组成。此外，神经元对皮肤输入的敏感性会随着手部形态而变化。我们假设这些感受野是触觉物体识别的基础核心。
