Extent and limits of callosal plasticity: Presence of disconnection symptoms in callosal agenesis

摘要: Abstract Although earlier studies have emphasized the absence of ‘split-brain’ symptoms in callosal agenesis patients, notion an ‘asymptomatic’ acallosal brain has lately been challenged. We report a number findings that are indicative interruption interhemispheric communication and integration individuals lacking corpus callosum. Several groups patients with pathology (acallosals, commissurotomy or callosotomy, either complete partial) were compared to matched controls. Interhemispheric transfer was tested two different experiments involving pointing light source while maintaining central fixation. In first experiment, learning paradigm used measure motor skill from trained untrained hand. second subjects pointed visual targets at locations on perimeter. Midline fusion, recurrent theme when describing function, assessed using tasks which included depth perception binocular and/or monocular cues, two-point discrimination thresholds sound localization peri-central lateral fields. Subjects impaired all visuo-spatial skills some requiring sensory tactile information across body midline. conclude these functions require intact callosum since none deficits seen controls equated for IQ.