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The common saying “think before you speak” is often used after a person spoke something inappropriate. It implies that the person in question has not given enough thought to the consequences of his spoken words. Obviously we can’t speak without thinking, though, so naturally the question arises: how do we plan out our utterances? Researchers at the Max Planck Institute for Psycholinguistics in Nimwegen sought to answer this question. Their findings suggest that the temporal coordination of thought and speech depends on the situation, namely on how complex it is. If the situation requires simple descriptions and dialogue, the speaker will in most cases plan the utterances in advances, while in the case of a more complex speech, the speaker will start with an initial portion pre-planned and improvise on the go.

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Antje Meye and her colleagues at MPI were particularly interested in how the thoughts we want to express in speech become gradually formed, and most importantly if this process, once found, is the same in all situations and for all individuals.

A strategy for planning your thoughts

To see how far in advance someone plans his speech, the researchers devised an experiment. Study participants were asked to describe various scenes, like those comprised of an “agent” figure (for instance a girl that is shown performing an action) and a “patient” (a boy that undergoes the action). While they described the scene, the participants were recorded to later decode speech signals and had an eye movement camera strapped on. This approach is based on the general principle that we usually direct our gaze where there is something “important” to be seen, that is, for example, the person performing an action, about whom we would like to speak. Knowing when a speaker directs his attention towards an object of interest, scientists can infer that this is the moment the subject begins to form related thoughts, selects corresponding words from memory and begins his speech.

So how do we plan our speech? Previously there have been two proposed hypotheses:

1. Speakers are only able to define the first concept and first word before the utterance. According to this theory as soon as a subject looks at an image, he directs his attention towards an object of interest (say the girl in the scene) and begins to speak immediately.
2. Speakers are able before the beginning of the utterance to roughly determine what happens in the image, meaning who does what. The subject looks directs his attention to multiple objects of interest and, possibly, other secondary elements before commencing his speech. Thus a more complex planning strategy is expressed compared to the fist hypothesis.

A third possibility considered, this time, by the MPI researchers is that speakers do not use either of these strategies consistently and that their speech planning depends on the difficulty of the task to be completed.  To determine whether or not this is true, the scientists presented subjects with scenes of various complexity; some images were very easy to recognize from the head-go, while others required a bit more thought. The test subjects were not given any specific instructions regarding the nature and length of the descriptions.

Proportion of fixations (gazes) on the agent (person acting) and patients (object of the action) when describing simple situations (a) and more complex situations (b). In the case of simple situations, the spoken utterance begins slightly later than in complex ones (vertical line in the graphs) because the speaker plans further in advance in the first case. © MPI for Psycholinguistics

The graph above shows which proportion of all gazes is directed at the agent (black) and the patient (grey) for each point in time from the commencement of the image. The utterances began after around 1.8 to 2 seconds. In general, the test subjects tend to view the agent initially rather than the patient. However, when the action was easy to describe  , the preference for the agent was not very marked.

Prepare or improvise

This suggests that people, when confronted with a simple situation, will begin by establishing an overview of the events  (looking both at agent and patient), then form a thought pattern. In contrast, when the action was more difficult to describe, the test subjects tended to limit themselves to looking at the person performing the action before the start of the utterance.

This and other evidence tells us that there isn’t one governing planning strategy, rather a more flexible approach depending on the situation is used. Therefore, we can plan our utterances in different ways and think in advance to various extents.

The implications of the findings are important for studies of linguistics and psycholinguistics, particularly  the extent to which the structure of language influences thinking. The study was made with the help of participants who are Dutch speaking natives. In Dutch, like in German or English, the agent is named first and then the action. In some langues like Tzeltal, which is spoken in Mexico and Tagalog, which is spoken in the Philippines,  the verb is placed at the beginning of the sentence. Considering the MPI findings, it’s assumable that people speaking these kind of languages  differ considerably in their approach to planning units. The MPI researchers in Nimwege plan on investigating these language patterns in the future, in hope that armed with more thorough empirical insight, the psycholinguists can better explore how language and thinking are related to each other.