Semantic conditioning of salivary pH for communication.

Abstract

Semantic conditioning of salivary pH was investigated as a new paradigm for binary communication. In a sample of eleven healthy participants, affirmation or negation of presented statements were paired with milk and lemon to condition changes in salivary pH level. Significant differences between the conditioned reactions were found at the group level. However, the analysis of pH changes on single-subject level revealed significant differences between affirmative and negative responses to the presented statements only for isolated samples in few participants. When classifying a change in pH value of more than .01 as correct response to a statement, only responses to affirmative statements reached mean accuracies of more than 60%. Improvements in the paradigm are necessary before testing it with the critical target population of patients to prove its profit for basic yes/no communication in case no other reliable means of communication could be preserved.