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Key points
- Conversations are central to innovation and human nature. Yet how we pull off even a single conversation remains poorly understood.
- Neuroscience reveals the previously hidden act of building a shared context together in a conversation.
- Building a shared context together in a conversation supports conversation with and without language.
From fleeting small talk to that ever-growing social media thread, everyday life is laced with conversations. Not all conversations might seem consequential.
But like the flap of a butterfly’s wing, one conversation can set off a cascade of reality-changing events, as when we come to collectively agree on a new social norm or virtual currency. It is clear that conversations are central to innovation and human nature. However, how we pull off even a single conversation remains much less understood.
More Than Words
Superficially, conversation revolves around an exchange of words. One person encodes meaning into words transmitted to another person, who then decodes the words to arrive at their original meaning.
This type of handoff is frequently seen in the animal world, where a South African honeybee signaling the location of a flower patch would be immediately understood in a New Zealand beehive.
Human conversation is different, however. We can employ our everyday words and gestures in virtually infinite ways. For example, we might use “bank” to refer to a financial institute (money bank), geographical feature (riverbank), a meteorological phenomenon (bank of clouds), a play in sports (bank shot), and so on. Not to mention our figurative language use.
Despite this flexibility, our conversation partner can usually grasp the intended meaning of our word at its first occurrence, thanks to its context of use. But how do we determine what counts as context, much less a shared context, when we continuously modify what we are talking about as we move through a conversation?
Building Shared Context Together
Motivated to understand our conversational abilities, the neuroscience of human interaction is emerging. And it has begun to reveal a previously hidden process.
When we produce words and other behaviors during a conversation, we are not just transmitting information. We are implicitly using those behaviors as a tool to organize and align our thoughts with one another to the extent they form a shared context.
This is seen in how a barista’s “what size?” constitutes more than a counter-question regarding quantity. It additionally conveys the ability and willingness to process our coffee order, allowing us to update our shared context with that knowledge.
By considering the current shared context, we can rapidly zero in on relevant details and possible interpretations of each other’s utterances, as when we implicitly infer the barista is not asking for our shoe size.
Thus, shared context is a mutually coordinated construct, continuously revised and adjusted in both minds as the conversation unfolds.
Conversation Without Language
One might wonder if our conversational abilities are so foundational that they allow us to build a meaningful shared context from scratch, thus even in situations deprived of a helpful common language?
Studies immersing pairs of participants in novel computer-mediated interactive settings, where they cannot see or talk to one another indicate this is the case. For instance, dyads quickly develop ways to make conversational use of initially meaningless behaviors, such as the digital movements of a geometric shape.
A study using two scanners confirmed the dyads achieved this through coordinating a shared context. Brains became synchronized in participant pairs with a shared history, over a timescale decoupled from individual behaviors, and only when they negotiated the meaning of those behaviors. Conversely, the coordination-dependent synchronization was reduced when dyads used behaviors that both parties already understood.
Finally, a recent study suggests that building shared contexts may be particularly challenging for individuals on the autism spectrum. Autistic individuals struggled to rapidly converge on a shared meaning for their shape movements with their conversation partners when meaning required referencing their recent interaction history.
This finding explains why the interactional difficulties characteristic of autism are most evident in everyday situations where words are being used in a highly context-dependent manner, such as in the case of irony and sarcasm.
To sum up, it’s still early in the neuroscience of conversation, but the first signs are emerging of a powerful and creative act underlying everyday conversation. Our ability to build a shared context enables us to bootstrap conversation jointly, even in situations deprived of a common language.
Language itself might be the collective product of our conversational abilities, as seen in how we acquire it from scratch and continue to develop it in everyday use.
References
Stolk, A., Noordzij, M.L., Verhagen, L., Volman, I., Schoffelen, J.M., Oostenveld, R., Hagoort, P. & Toni, I. (2014). Cerebral coherence between communicators marks the emergence of meaning. Proceedings of the National Academy of Sciences 111, 18183-18188
Wadge, H., Brewer, R., Bird, G., Toni, I. & Stolk, A. (2019). Communicative misalignment in Autism Spectrum Disorder. Cortex 115, 15-26
Stolk, A., Bašnáková, J. & Toni, I. (2022). Joint epistemic engineering: The neglected process of context construction in human communication. PsyArXiv: https://psyarxiv.com/rwfe6/
