This paper presents experiments where natural and spontaneous cognitive processes, in particular those who lead to the attribution of personality traits to unacquainted people, are used as a natural form of feature extraction. In particular, personality assessments provided by human judges are used as features to distinguish between professional and non-professional speakers. The same task is performed with prosodic features extracted with a fully automatic process for comparison purposes. Furthermore both prosodic features and personality assessments are combined. The results show that the discrimination between professional and non-professional speaking styles can be performed with an accuracy of 87.2% when using prosodic features, of 75.5% when using personality assessments, and of 90.0% when using the combination of the two.