Central mechanisms of tactile shape perception.
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.
Hsiao
Steven
S
Department of Neuroscience and the Krieger Mind/Brain Institute, The Johns Hopkins University, 338 Krieger Hall, Baltimore, MD 21218, United States. Steven.Hsiao@jhu.edu
D000818:Animals; D004192:Discrimination, Psychological / Q000502:physiology; D006801:Humans; D009474:Neurons / Q000502:physiology*; D009949:Orientation / Q000502:physiology; D011434:Proprioception / Q000502:physiology*; D012867:Skin / Q000294:innervation; D013003:Somatosensory Cortex / Q000166:cytology / Q000502:physiology*; D014110:Touch / Q000502:physiology*