Lingual discoordination and dysphagia following acute stroke: Analyses of lesion localization

The mechanism and neural substrates that mediate lingual coordination durin g swallowing have not been well characterized. Although lingual discoordina tion during swallowing has been difficult to quantify, it has been defined as the random disorganization of anterior-posterior tongue movements eviden t in bolus propulsion. In a sample of consecutive acute stroke patients (n = 59), videofluoroscopic evaluation showed a 19% incidence of lingual disco ordination during swallowing. Lingual discoordination during swallowing was not commonly associated with buccofacial apraxia, apraxia of speech, nor l imb apraxia. Hemisphere and anterior-posterior localization did not predict occurrence of lingual discoordination. Lingual discoordination during swal lowing occurred commonly in patients with subcortical lesions with the peri ventricular white matter (PVWM), the most common site of involvement. PVWM lesions may disconnect anterior and posterior cortical regions that are cri tical to oral control and coordination in swallowing, thereby producing lin gual discoordination during swallowing. These data also suggest that the ne ural mechanisms that mediate lingual coordination may at least in part be i ndependent of the neural systems that mediate buccofacial, limb, and speech praxis functions.