Mixed logit analysis results for Experiment 2 are presented in Table 2 . The critical result is that conception risk does not affect the odds of the participants matching the syntactic construction produced by the confederates (p = .93). Whereas changes in conception risk affected the extent to which heterosexual males matched the syntactic constructions produced by female confederates, heterosexual females display no such change in linguistic alignment as a function of conception risk. Caution is always in order when interpreting null results (particularly as the sample size of this study is somewhat smaller than the sample size of Experiment 1 ), but these data nonetheless suggest that the linguistic behavior of heterosexual males and females is affected in different ways by cues to female fertility.

We conducted preliminary analyses to determine whether changes in conception risk were accompanied by other changes that might account for the effects of conception risk on structural priming. None of the participants' ratings of the confederates were significant predictors of conception risk (p's>.13), and the combination of all of the variables did not significantly predict conception risk [F<1]. We also assessed whether there was a reliable structural priming effect in this study. Participants matched the syntactic construction produced by the confederates on 56% of the trials (M = .56, SD = .11), a figure that is significantly different than 50% [t(44) = 3.35, p = .002].

General Discussion

Conception risk was inversely related to structural priming in heterosexual males: the higher the level of fertility in a female conversation partner, the lower the level of structural alignment men displayed. No such effect was observed in heterosexual females. The observed relationship between conception risk and structural priming is consistent with the second possibility considered in the introduction, namely that detection of fertility cues would be associated with higher levels of non-conforming or creative behavior (such as not aligning one's linguistic choices with those of a conversation partner). We follow the claims of Miller and Maner [20] in making the following proposal for how conception risk interacts with structural priming: 1) detection of fertility cues activates mating goals in men, 2) the activation of mating goals in turn leads to displays of fitness as a mate (such as creative or non-conforming behavior), and 3) non-conformity and creativity within our task manifested itself as the participants not aligning their syntactic choices with those of their partner. The data at hand do not allow us to determine whether the lack of alignment between males and the female confederates during periods of high fertility is best characterized as non-conformity or creativity. Whatever the case may turn out to be, both possibilities are consistent with the general claim that the reduction in alignment seen in Experiment 1 may be characterized as a display of fitness as a mate.

Although we are only beginning to scratch the surface with respect to understanding how conception risk affects structural priming, our data do provide some hints about the nature of the effect that is observed. The lack of an interaction between relationship status and conception risk (i.e., this predictor did not significantly add to model fit in Experiment 1, suggesting that the effect of conception risk was the same whether or not the male was in a committed relationship) suggests that the effect seen here reflects nonconscious, implicit changes in linguistic behavior. Miller and Maner [20], [22] demonstrated that relationship status affects men's responses to fertility cues when explicit behaviors are examined (e.g., providing ratings of the attractiveness of a woman), but not when implicit behaviors are examined (e.g., assessing the priming of concepts via a stem completion task). The idea that the effects of conception risk on structural priming reflect implicit, nonconscious behaviors on the part of the participant is consistent both with the theoretical position that structural priming reflects implicit learning in the language production system [26], [36], [37], and with claims that many sorts of behavioral and linguistic mimicry during interpersonal interaction occur on a nonconscious level [9], [20], [6], [38].

Participant ratings of the confederates' flirtatiousness were related to structural priming. Participants did not find the confederates to be especially flirtatious (mean rating = 1.95 out of 5), but those who did showed stronger structural priming. This result is consistent with the broad literature showing that conversational partners show affiliation by aligning their linguistic behavior [6]. Given that flirtatiousness and conception risk are both relevant to mating goals, it raises the question of why conception risk and flirtatiousness affected structural priming in opposite directions. We propose the following answer. When the participant perceives the confederate as flirtatious (i.e., he perceives interest on the part of the confederate), there is no need to signal fitness as a mate – the female has already signaled her interest. As such, the appropriate social strategy is to reciprocate the affiliation shown by the confederate. Within the context of our task, this can be accomplished by matching the structure of the utterances produced by the confederate. However, when the participant does not perceive the confederate as particularly flirtatious (as was likely the case for many of the participants in our study), the confederate has not signaled any particular interest in the participant. As such, when cues to fertility activate mating goals in the participant, the appropriate social strategy is to signal fitness as a mate in an effort to increase interest on the part of the confederate.

Although our reported effect of conception risk on structural priming is consistent with some elements of the literature on romantic relationships (particularly the idea that men may use non-conforming behavior to stand out to female conversation partners), the effect would appear to be at odds with a wide range of data suggesting that attraction to a conversational partner should lead to an increase in matching behavior [6], [12]. Indeed, at first blush the expectation that increases in fertility should lead to increases in alignment would appear to be the obvious prediction for our study. The contradiction between our data and previous work on alignment in conversation raises the possibility that there may be something unusual about our interaction setting that is driving the nature of the relationship between conception risk and structural priming. This concern is ameliorated to an extent by the finding that flirtatiousness leads to an increase in matching, as would be predicted on the “affiliation = alignment” view. Thus, our conversational task does reveal an expected social effect on alignment (as well as the traditional structural priming effect), but it appears that conception risk and the associated activation of mating goals may motivate speakers' behavior in a different way than the perception of flirtatiousness in the confederate.

Ireland et al. [12] note the paucity of research on linguistic behavior in relationships, and further note the importance of linguistic alignment (or a lack thereof) as a predictor of the promise and stability of a relationship. Our data add to this literature by suggesting that the role of linguistic behavior in the development of romantic relationships may not be as simple as the idea that people will align their linguistic behavior with that of attractive potential mates. Indeed, conversation partners may align their linguistic behavior (or not) based on a range of factors. If the potential mate has signaled interest in you, linguistic alignment may be a means of reciprocating that interest and developing a social bond. If the potential mate has not signaled an interest in you, non-alignment of linguistic choices may be a means of displaying one's fitness as a mate – and thereby capturing the potential mate's interest [21]. This proposal does not necessarily undermine the general claim that behavioral and linguistic alignment is an effective and commonly used means of building affiliation between individuals. Rather, it is intended to illustrate that linguistic behavior (aligning or non-aligning) can be driven by a range of social motivations, and that different social dynamics may affect both one's choice of behavior and the interpretation of that behavior. It is worth pointing out that even the act of aligning one's linguistic behavior with that of a conversation partner can serve multiple purposes – it can be affiliation-building in some cases, and affiliation-reducing in other cases (such as when the alignment is perceived as patronizing [6]).

Alignment is not an “all or nothing” variable. There are many different levels at which alignment can occur—both linguistically (e.g., sentence structure [8], lexical choices [39], and rate of speech [40]) and behaviorally (e.g., gestures [41], postures [42], and facial expressions [43]), and one can align on one level without aligning on other levels. The current study only examined one type of alignment—alignment of sentence structure. Therefore, we cannot determine whether men in our study diverged from fertile women on multiple levels or only on their choice of language structure. It may be the case that men in our study diverged from fertile women on sentence structure to accomplish certain goals (e.g., showing off their creativity or non-conformity to attract a mate) while aligning with them on other levels (e.g., rate of speech or vocal pitch) to accomplish other goals (e.g., affiliation). Previous research has not generally explored the extent to which alignment at one level corresponds to alignment at another level. The fact that fertility level affects the degree to which men align on linguistic choices differently than it affects the degree to which men align on behavior suggests that studying the relationship between different levels of interpersonal alignment may be a fruitful area for research.

We conclude with a broader point. For decades, social and cognitive approaches to language have had very little interaction (see [2] for a discussion). Our demonstration that a well-studied psycholinguistic phenomenon (structural priming) can be affected by social factors, combined with recent work on social aspects of language use [12], suggest that it may be profitable for researchers in both camps to pursue work at the intersection of cognitive and social approaches to language. It is our hope that findings such as these will spur interest in bridging these long-standing traditions of language research.