Back ground and Aim: Some left brain- damaged stroke patients display both oral and verbal apraxia, while others may appear to have one or none of them. So the present study was focused on investigating the severity and relationship of oral and verbal apraxia in these patients.

Materials and Methods: In this cross sectional descriptive-analytic study, 20 left hemisphere damaged patients due to a single ischemic CVA (8 women, 12 men) with an average age of 60.68 years (range, 35-73) were recruited using convenience sampling. An oral apraxia task was applied to examine imitation of oral motor gestures, and the verbal apraxia was tested by a speech production task. Data were analyzed by U Mann-Whitney, Kruskal-Wallis and Pearson correlation.

Results: Analysis of data revealed that 4 patients showed prominent oral apraxia, 12 patients suffered from prominent verbal apraxia and 4 had a combination of both types with relative equal severities. No significant correlation between oral apraxia and verbal apraxia was observed (p= 0.899).

Conclusion: According to the findings, the co-occurrence pattern of oral and verbal apraxia seems not to be a predictable one. Despite of the fact that ischemic lesions lead to damage of neighboring neural substrates, half of the patients revealed dissociation of oral and verbal apraxia. This dissociation may be interpreted as an evidence of a modular task-specific neuromotor control system , which considers non-speech oral movement control independent of speech motor control .

Key words: Apraxia, Oral apraxia, Verbal apraxia, oral apraxia prominence, Verbal apraxia prominence