title: Differences in Early Stages of Tactile ERP Temporal Sequence (P100) in Cortical Organization during Passive Tactile Stimulation in Children with Blindness and Controls.
abstract: Compared to their seeing counterparts, people with blindness have a greater tactile capacity. Differences in the physiology of object recognition between people with blindness and seeing people have been well documented, but not when tactile stimuli require semantic processing. We used a passive vibrotactile device to focus on the differences in spatial brain processing evaluated with event related potentials (ERP) in children with blindness (n = 12) vs. normally seeing children (n = 12), when learning a simple spatial task (lines with different orientations) or a task involving recognition of letters, to describe the early stages of its temporal sequence (from 80 to 220 msec) and to search for evidence of multi-modal cortical organization. We analysed the P100 of the ERP. Children with blindness showed earlier latencies for cognitive (perceptual) event related potentials, shorter reaction times, and (paradoxically) worse ability to identify the spatial direction of the stimulus. On the other hand, they are equally proficient in recognizing stimuli with semantic content (letters). The last observation is consistent with the role of P100 on somatosensory-based recognition of complex forms. The cortical differences between seeing control and blind groups, during spatial tactile discrimination, are associated with activation in visual pathway (occipital) and task-related association (temporal and frontal) areas. The present results show that early processing of tactile stimulation conveying cross modal information differs in children with blindness or with normal vision.
authors.affiliation: Department of Psychiatry, Facultad de Medicina, Universidad Complutense, Madrid, Spain.
authors.forename: Tomás
authors.initials: T
authors.lastname: Ortiz Alonso
authors.affiliation: Department of Psychology, Universidad de Atacama, Copiapó, Chile and Fundación J Robert Cade/CONICET, Córdoba, Argentina.
authors.forename: Juan Matías
authors.initials: JM
authors.lastname: Santos
authors.affiliation: Athinoula A Martinos Center, Department of Radiology, Massachusetts General Hospital, Harvard University, Boston, Massachusetts, United States of America.
authors.forename: Laura
authors.initials: L
authors.lastname: Ortiz Terán
authors.affiliation: Centro de Neurociencias de Cuba, Habana, Cuba.
authors.forename: Mayelin
authors.initials: M
authors.lastname: Borrego Hernández
authors.affiliation: Department of Ear, Nose and Throat (ENT), Hospital Clínico Universitario San Carlos, Universidad Complutense, Madrid, Spain.
authors.forename: Joaquín
authors.initials: J
authors.lastname: Poch Broto
authors.affiliation: Center for Neuromodulation and Roskamp Laboratory of Brain Development, Modulation and Repair, Departments of Psychiatry, Neurology and Neurosurgery, University of South Florida, Tampa, Florida, United States of America.
authors.forename: Gabriel Alejandro
authors.initials: GA
authors.lastname: de Erausquin
mesh_terms: D001766:Blindness / Q000503:physiopathology*; D016022:Case-Control Studies; D002648:Child; D003071:Cognition / Q000502:physiology; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D010812:Physical Stimulation; D011930:Reaction Time / Q000502:physiology; D021641:Recognition, Psychology / Q000502:physiology; D012660:Semantics; D055698:Touch Perception / Q000502:physiology*