Complex Inferential Processes Are Needed for Implicature Comprehension, but Not for Implicature Production.

Upon hearing "Some of Michelangelo's sculptures are in Rome," adults can easily generate a scalar implicature and infer that the intended meaning of the utterance corresponds to "Some but not all Michelangelo's sculptures are in Rome." Comprehension experiments show that preschoolers struggle with this kind of inference until at least 5 years of age. Surprisingly, the few studies having investigated children's production of scalar expressions like some and all suggest that production is adult-like already in their third year of life. Thus, children's production of implicatures seems to develop at least 2 years before their comprehension of implicatures. In this paper, we present a novel account of scalar implicature generation in the framework of Bidirectional Optimality Theory: the Asymmetry Account. We show that the production-comprehension asymmetry is predicted to emerge because the comprehension of some requires the hearer to consider the speaker's perspective, but the production of some does not require the speaker to consider the hearer's perspective. Hence, children's comprehension of scalar expressions, but not their production of scalar expressions, is predicted to be related to their theory of mind development. Not possessing fully developed theory of mind abilities yet, children thus have difficulty in comprehending scalar expressions such as some in an adult-like way. Our account also explains why variable performance is found in experimental studies testing children's ability to generate scalar implicatures; moreover, it describes the differences between children's and adults' implicature generation in terms of their ability to recursively apply theory of mind; finally, it sheds new light on the question why the interpretation of numerals does not require implicature generation.

Event-related potentials reveal increased dependency on linguistic context due to cognitive aging.

Whereas executive functions are known to be closely tied to successful language processing in children and younger adults, less is known about how age-related decline in these functions affects language processing in elderly adults. Because the abilities to use linguistic context and resolve potential ambiguities such as between an idiom's figurative and literal meaning depend on executive functions, we investigated this issue by examining elderly adults' processing of idioms in context. We recorded event-related potentials of 25 younger (age 18-28) and 25 elderly adults (age 61-74) while they read literal sentences and sentences containing an idiom (e.g., the Dutch idiom to walk against the lamp, meaning "to get caught"), each preceded by a neutral or predictive context sentence. Participants' use of context was hypothesized to relate to working memory capacity, while their ability to disambiguate idioms was hypothesized to depend on inhibition skills. Both groups showed facilitated processing for idioms compared with literal sentences and for sentences preceded by predictive compared with neutral contexts, indexed by a reduced N400. However, only elderly adults showed an increased P600 for literal but not idiomatic sentences preceded by a predictive context, suggesting that they rely on linguistic context when a sentence's meaning needs to be computed word by word, but not when a large part is retrieved from memory (as in idioms). Our findings suggest that in both younger and elderly adults processing literal sentences requires more cognitive effort than processing idiomatic sentences, and that cognitive aging affects language when processing is effortful. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Age Effects in L2 Grammar Processing as Revealed by ERPs and How (Not) to Study Them.

In this study we investigate the effect of age of acquisition (AoA) on grammatical processing in second language learners as measured by event-related brain potentials (ERPs). We compare a traditional analysis involving the calculation of averages across a certain time window of the ERP waveform, analyzed with categorical groups (early vs. late), with a generalized additive modeling analysis, which allows us to take into account the full range of variability in both AoA and time. Sixty-six Slavic advanced learners of German listened to German sentences with correct and incorrect use of non-finite verbs and grammatical gender agreement. We show that the ERP signal depends on the AoA of the learner, as well as on the regularity of the structure under investigation. For gender agreement, a gradual change in processing strategies can be shown that varies by AoA, with younger learners showing a P600 and older learners showing a posterior negativity. For verb agreement, all learners show a P600 effect, irrespective of AoA. Based on their behavioral responses in an offline grammaticality judgment task, we argue that the late learners resort to computationally less efficient processing strategies when confronted with (lexically determined) syntactic constructions different from the L1. In addition, this study highlights the insights the explicit focus on the time course of the ERP signal in our analysis framework can offer compared to the traditional analysis.

Prolonged L2 immersion engenders little change in morphosyntactic processing of bilingual natives.

Bilingual and monolingual language processing differ, presumably because of constant parallel activation of both languages in bilinguals. We attempt to isolate the effects of parallel activation in a group of German first-language (L1) attriters, who have grown up as monolingual natives before emigrating to an L2 environment. We hypothesized that prolonged immersion will lead to changes in the processing of morphosyntactic violations. Two types of constructions were presented as stimuli in an event-related potential experiment: (1) verb form combinations (auxiliaries+past participles and modals+infinitives) and (2) determiner-noun combinations marked for grammatical gender. L1 attriters showed the same response to violations of gender agreement as monolingual controls (i.e. a significant P600 effect strongest over posterior electrodes). Incorrect verb form combinations also elicited a significant posterior P600 effect in both groups. In attriters, however, there was an additional posterior N400 effect for this type of violation. Such biphasic patterns have been found before in L1 and L2 speakers of English and might reflect the influence of this language. Generally, we interpret our results as evidence for the stability of the deeply entrenched L1 system, even in the face of L2 interference.

The impact of language co-activation on L1 and L2 speech fluency.

Fluent speech depends on the availability of well-established linguistic knowledge and routines for speech planning and articulation. A lack of speech fluency in late second-language (L2) learners may point to a deficiency of these representations, due to incomplete acquisition. Experiments on bilingual language processing have shown, however, that there are strong reasons to believe that multilingual speakers experience co-activation of the languages they speak. We have studied to what degree language co-activation affects fluency in the speech of bilinguals, comparing a monolingual German control group with two bilingual groups: 1) first-language (L1) attriters, who have fully acquired German before emigrating to an L2 English environment, and 2) immersed L2 learners of German (L1: English). We have analysed the temporal fluency and the incidence of disfluency markers (pauses, repetitions and self-corrections) in spontaneous film retellings. Our findings show that learners to speak more slowly than controls and attriters. Also, on each count, the speech of at least one of the bilingual groups contains more disfluency markers than the retellings of the control group. Generally speaking, both bilingual groups-learners and attriters-are equally (dis)fluent and significantly more disfluent than the monolingual speakers. Given that the L1 attriters are unaffected by incomplete acquisition, we interpret these findings as evidence for language competition during speech production.

An ERP study on L2 syntax processing: When do learners fail?

Event-related brain potentials (ERPs) can reveal online processing differences between native speakers and second language (L2) learners during language comprehension. Using the P600 as a measure of native-likeness, we investigated processing of grammatical gender agreement in highly proficient immersed Romance L2 learners of Dutch. We demonstrate that these late learners consistently fail to show native-like sensitivity to gender violations. This appears to be due to a combination of differences from the gender marking in their L1 and the relatively opaque Dutch gender system. We find that L2 use predicts the effect magnitude of non-finite verb violations, a relatively regular and transparent construction, but not that of gender agreement violations. There were no effects of age of acquisition, length of residence, proficiency or offline gender knowledge. Additionally, a within-subject comparison of stimulus modalities (written vs. auditory) shows that immersed learners may show some of the effects only in the auditory modality; in non-finite verb violations, an early native-like N400 was only present for auditory stimuli. However, modality failed to influence the response to gender. Taken together, the results confirm the persistent problems of Romance learners of Dutch with online gender processing and show that they cannot be overcome by reducing task demands related to the modality of stimulus presentation.

Pupil dilation co-varies with memory strength of individual traces in a delayed response paired-associate task.

Studies on cognitive effort have shown that pupil dilation is a reliable indicator of memory load. However, it is conceivable that there are other sources of effort involved in memory that also affect pupil dilation. One of these is the ease with which an item can be retrieved from memory. Here, we present the results of an experiment in which we studied the way in which pupil dilation acts as an online marker for memory processing during the retrieval of paired associates while reducing confounds associated with motor responses. Paired associates were categorized into sets containing either 4 or 7 items. After learning the paired associates once, pupil dilation was measured during the presentation of the retrieval cue during four repetitions of each set. Memory strength was operationalized as the number of repetitions (frequency) and set-size, since having more items per set results in a lower average recency. Dilation decreased with increased memory strength, supporting the hypothesis that the amplitude of the evoked pupillary response correlates positively with retrieval effort. Thus, while many studies have shown that "memory load" influences pupil dilation, our results indicate that the task-evoked pupillary response is also sensitive to the experimentally manipulated memory strength of individual items. As these effects were observed well before the response had been given, this study also suggests that pupil dilation can be used to assess an item's memory strength without requiring an overt response.