Sources of variability in human communicative skills

Abstract

When established communication systems cannot be used, people rapidly create novel systems to modify the mental state of another agent according to their intentions. However, there are dramatic inter-individual differences in the implementation of this human competence for communicative innovation. Here we characterize psychological sources of inter-individual variability in the ability to build a shared communication system from scratch. We consider two potential sources of variability in communicative skills. Cognitive traits of two individuals could independently influence their joint ability to establish a communication system. Another possibility is that the overlap between those individual traits influences the communicative performance of a dyad. We assess these possibilities by quantifying the relationship between cognitive traits and behavior of communicating dyads. Cognitive traits were assessed with psychometric scores quantifying cooperative attitudes and fluid intelligence. Competence for implementing successful communicative innovations was assessed by using a non-verbal communicative task. Individual capacities influence communicative success when communicative innovations are generated. Dyadic similarities and individual traits modulate the type of communicative strategy chosen. The ability to establish novel communicative actions was influenced by a combination of the communicator's ability to understand intentions and the addressee's ability to recognize patterns. Communicative pairs with comparable systemizing abilities or behavioral inhibition were more likely to explore the search space of possible communicative strategies by systematically adding new communicative behaviors to those already available. No individual psychometric measure seemed predominantly responsible for communicative success. These findings support the notion that the human ability for fast communicative innovations represents a special type of complex collaborative activity.

Keywords: cooperation; interactive intelligence; joint action; social cognition; tacit communication game.

Figure 1

The EQ and SQ-R scores of the participants with the boundaries of different types according to Wheelwright et al. (2006).

Figure 2

A timeline corresponding to the sender's and receiver's observations and actions during the OLD trials. The sender and the receiver saw the images presented in the left and right column, respectively. A trial started with a fixation point presented on the screen (#1). After 2 s the game board and the tokens appeared (#2). Then the goal configuration was shown to the sender, and not to the receiver. The goal configuration consisted of two tokens inside the game board (#3). The sender had unlimited time to look at the goal configuration and plan his moves. After the sender pressed the start button, all tokens disappeared and the sender's token appeared in the center of the game board (#4). The sender had 5 s to move his token within the game board (#5, 6). A yellow bar under the receiver's token indicated that the 5 s had passed and the receiver could start to move (#7). The receiver had unlimited time to plan his moves. After the receiver pressed his start button, his token appeared at a random location on the game board (with the exclusion of the goal positions of either sender or receiver) (#8). After the first move, the receiver had 5 s to move within the game board (#9). When the receiver finished within 5 s, he could end his turn by pressing the start button. The participants received visual feedback about their performance (#10). A green rectangle indicated a correct match with the goal configuration, a red rectangle an incorrect match.

Figure 3

Examples of goal configurations from different communicative problems and the corresponding shape combinations. The tokens are matched in shape for OLD and NEW problems, but with different communicative roles. Note that in shape combination three, the triangle is pointing toward the game board, whereas in shape combination four the triangle is pointing away from the game board.

Figure 4

Timecourse of task performance (accuracy, in %) over all pairs.

Figure 5

The different strategies used by four pairs with respect to the NEW problem. The Roman numerals indicate different strategies, as described in the main text.

Figure 6

(A) Mean accuracy scores for OLD and NEW problems for each pair of participants. (B) Scatterplot of the relation between performance during NEW trials, senders' Need for Cognition score, and receivers' Raven score. (C) Scatterplot of the relation between frequency of using a COARSE strategy and senders' Raven scores. (D) Scatterplot of the relation between frequency of using a REFINED strategy, within-pairs SQ-R mismatch score, and within-pairs BIS mismatch score.