What drives successful verbal communication?

Abstract

THERE IS A VAST AMOUNT OF POTENTIAL MAPPINGS BETWEEN BEHAVIORS AND INTENTIONS IN COMMUNICATION: a behavior can indicate a multitude of different intentions, and the same intention can be communicated with a variety of behaviors. Humans routinely solve these many-to-many referential problems when producing utterances for an Addressee. This ability might rely on social cognitive skills, for instance, the ability to manipulate unobservable summary variables to disambiguate ambiguous behavior of other agents ("mentalizing") and the drive to invest resources into changing and understanding the mental state of other agents ("communicative motivation"). Alternatively, the ambiguities of verbal communicative interactions might be solved by general-purpose cognitive abilities that process cues that are incidentally associated with the communicative interaction. In this study, we assess these possibilities by testing which cognitive traits account for communicative success during a verbal referential task. Cognitive traits were assessed with psychometric scores quantifying motivation, mentalizing abilities, and general-purpose cognitive abilities, taxing abstract visuo-spatial abilities. Communicative abilities of participants were assessed by using an on-line interactive task that required a speaker to verbally convey a concept to an Addressee. The communicative success of the utterances was quantified by measuring how frequently a number of Evaluators would infer the correct concept. Speakers with high motivational and general-purpose cognitive abilities generated utterances that were more easily interpreted. These findings extend to the domain of verbal communication the notion that motivational and cognitive factors influence the human ability to rapidly converge on shared communicative innovations.

Keywords: Raven’s progressive matrices; communication; individual differences; language; mentalizing.

FIGURE 1

(A) Time line of the Taboo game. In an fMRI experiment Communicators had to describe a Target-word (“beard”) to an Addressee (confederate) without using Taboo-words (“hair,” “chin,” “man,” “shave” and “mostache”). In the TARGETED setting (depicted in red), Communicators were made to believe that the Addressee was unbeknownst of the Target-word (right empty box next to the Target-word “beard”). In the NON- TARGETED setting (depicted in blue), Communicators were aware that the Addressee already knew the Target-word. Communicators were reminded of this by printing the Target-word twice on the Communicator’s screen. (B) Obtaining indications of communicative success (in green). First, Evaluators, naive of the Taboo game experiment, listened to the Target- word description made during the Taboo game. Second, Evaluators were asked to consider which Target-word they thought was described. Third, they were to type in their answer (Guess-word) and lastly, they filled out how difficult they found it to come up with their answer on a scale from one till five (1 “easy,” 5 “difficult”; certainty scores). A measure of Communicators’ success was obtained by counting the Evaluators’ correct guesses divided by the total amount of trials per condition.

FIGURE 2

Communicative success as evaluated by a new group of participants (in percentage correct) plotted against the psychometric indexes of the Communicators. (A) Communicators’ scores on motivation for complex tasks as indexed by the NCS (R² = 0.3, p < 0.05, regression line is solid, data points represented as dots) drive communicative success in the communicative setting (TARGETED condition). (B) Communicators’ scores on general intelligence as indexed by Raven’s Advanced Progressive Matrices (RAPM, R² = 0.32, p < 0.05, regression line is solid, data points represented as closed dots) drive communicative success in the TARGETED setting compared to the NON-TARGETED setting. A positive difference score indicates that Communicators performed better in the TARGETED setting, a negative score that Communicators performed better in the NON-TARGETED setting. To correct for individual differences in general performance on the Taboo game, a model to account for communicative success during the targeted setting compared with the NON-TARGETED setting was created. The difference in accuracy scores between the two conditions was positively driven by the Communicator’s general intelligence as indexed by the Raven’s APM. Neither the EQ, nor any of the IRI subscales could account for the difference in success across the communicative settings.