Swallowing apraxia: a disorder of the Praxis system?

The purpose of this review is to evaluate the disorder of swallowing apraxia and determine how it fits into the praxis system. Swallowing apraxia, a proposed disorder of lingual, labial, and mandibular coordination, has been observed before bolus transfer during the oral stage of swallowing. Although frequently discussed anecdotally in dysphagia literature, the possible mechanisms and neural networks of swallowing apraxia have not been elucidated. Similarities and differences of swallowing apraxia with buccofacial, speech, and limb apraxias are evident. Critical review of the literature has identified possible similarities as greater occurrence upon command, transitive nature of the action, and evidence of spatial errors. Conversely, differences such as hemispheric lateralization and multiple gesture assessment may exist between swallowing apraxia and more traditional forms of apraxia. Until discrete error patterns of swallowing apraxia are identified and precisely measured, the nature of this disorder and its relationship with the praxis system will continue to remain elusive.