The Mental Lexicon - Volume 8, Issue 3, 2013

This paper studies the robustness of exemplar effects in word comprehension by means of four long-term priming experiments with lexical decision tasks in Dutch. A prime and target represented the same word type and were presented with the same or different degree of reduction. In Experiment 1, participants heard only a small number of trials, a large proportion of repeated words, and stimuli produced by only one speaker. They recognized targets more quickly if these represented the same degree of reduction as their primes, which forms additional evidence for the exemplar effects reported in the literature. Similar effects were found for two speakers who differ in their pronunciations. In Experiment 2, with a smaller proportion of repeated words and more trials between prime and target, participants recognized targets preceded by primes with the same or a different degree of reduction equally quickly. Also, in Experiments 3 and 4, in which listeners were not exposed to one but two types of pronunciation variation (reduction degree and speaker voice), no exemplar effects arose. We conclude that the role of exemplars in speech comprehension during natural conversations, which typically involve several speakers and few repeated content words, may be smaller than previously assumed.

In three experiments, we examined the effects of accents and production on free recall and yes/no recognition memory. In the study phase, native English participants heard English words pronounced by a speaker with an accent that is highly familiar to the participant (American English) or with a less familiar accent (Dutch). Participants had to either say aloud (produce) the word that they heard in their natural pronunciation (Exp. 1a) or imitate the original speaker (Exp. 1b) or simply listen to the word. In all experiments, in both recall and recognition, produced words and words spoken in an unfamiliar accent were more likely to be recalled and more likely to be recognized, than words that were listened to or words spoken in a more familiar accent. In recognition but not in recall, listening to words spoken in an unfamiliar accent improved memory more than listening to words spoken in a familiar accent. Results suggest that listening allows the acoustic-phonetic details of a speaker to be retained in memory, but that production attenuates details about the original speaker’s pronunciation. Finally, the benefit of production for memory does not differ whether one produces in one’s natural accent or imitates that of the speaker.

Regular plural nouns rarely appear as the first member of a compound noun in English under any circumstances, while irregular plurals are more likely under certain conditions. One explanation holds that this is a consequence of the fundamentally different ways in which regular and irregular plurals are stored and processed, while an alternative explanation suggests that it may be rooted in phonological differences between regular and irregular forms. If the first part of a compound is phonologically restricted, the restrictions may interact with lexical access in a way that disfavors regular plurals (especially given that plurals of any sort are of low frequency in the first part of a compound, so processing is far from ceiling). This paper provides evidence from a case study of one child that the first part of a compound can be phonologically restricted compared to nouns when they appear as independent words. The data address compounds whose first elements are monomorphemic nouns, rather than plurals, but document the existence of phonological restrictions within compounds for at least one child This existence proof strengthens the hypothesis that differences between regular and irregular forms may derive partly from differences in phonological structure.

This study investigates the masked onset priming effect (MOPE) in Korean. The results revealed facilitated naming for nonwords written in the alphabetic syllabary hangul when primes and targets shared an initial consonant-vowel (CV) syllable as well as when they shared only an initial onset (C) phoneme. However, there was greater priming at the syllable level than at the phoneme level. Taken together with previous research on Korean (Kim & Davis, 2002), these findings indicate that the MOPE reflects facilitated grapheme-to-phoneme conversion processes when the pronunciation of the target is computed through the nonlexical route, and are interpreted to support the Forster and Davis (1991) model of this effect.

In language change, a reversal of a merger is generally considered to be impossible, since after two sounds have become fully merged, they are no longer distinct, so no phonetic or phonological cues exist that could reverse this process. This article investigates such an ‘impossible’ merger reversal: the split of Bären vowel (orthographically represented by <ä> or <äh>) and the Beeren vowel (orthographically represented by , or in Austrian Standard German. We investigated a corpus of spoken data, measured the acoustic properties of the vowels, and determined the degree of the merger (by computing Pillai scores) for younger and older speakers. It turns out that the two sounds were formerly merged, but currently a split can be observed as an ongoing process. This paper argues that language contact with Standard German as it is spoken in Germany motivates the ongoing reversal. Since the long vowel <ä> is also subject to substantial variation in German Standard German, in order to get the split right, Austrian speakers are likely to invoke orthographical knowledge. We will consider the mental representations of this sound, including the graphemic representations from an Exemplar Theory viewpoint.

For L2-learners, confusable phonemic categories lead to ambiguous lexical representations. Yet, learners can establish separate lexical representations for confusable categories, as shown by asymmetric patterns of lexical access, but the source of this asymmetry is not clear (Cutler et al., 2006). Two hypotheses compete, situating its source either at the lexical coding level or at the phonetic categorization level. The lexical coding hypothesis suggests that learners’ encoding of an unfamiliar category is not target-like but makes reference to a familiar L1 category (encoded as a poor exemplar of that L1 category). Four experiments examined how learners lexically encode confusable phonemic categories. American English learners of Japanese and of German were tested on phonetic categorization and lexical decision for geminate/singleton contrasts and front/back rounded vowel contrasts. Results showed the same asymmetrical patterns as Cutler et al.’s (2006), indicating that learners encode a lexical distinction between difficult categories. Results also clarify that the source of the asymmetry is located at the lexical coding level and does not emerge during input categorization: the distinction is not target-like, and makes reference to L1 categories. We further provide new evidence that asymmetries can be resolved over time: advanced learners are establishing more native-like lexical representations.

The DMDX software package (Forster & Forster, 2003) is a Windows-based application that displays stimuli and records responses. Recent developments in this program have made it possible to deploy DMDX experiments over the Internet. This study evaluates the viability of the web-deployable implementation of DMDX, or webDMDX, for masked priming experiments. A lexical decision task (LDT) with masked repetition priming on high- and low-frequency words and an e/a letter detection task were conducted with both lab-based DMDX (labDMDX; Experiment 1) and webDMDX. The webDMDX experiments were run on lab computers (Experiments 2) and on different (unknown) hardware (Experiment 3). The labDMDX and webDMDX experiments yielded comparable results on the LDT. In the e/a-detection task, the only important difference observed among the tests was between the lab-based experiment (Experiment 1) and the first webDMDX experiment (Experiment 2), at the 50 ms display duration. However, after a minor change in keyword coding (Experiment 2 follow-up) and an adjustment to the millisecond-to-retrace conversion process (Experiment 3), the detection rates at all display durations were similar in both labDMDX and webDMDX. Taken together, these results indicate the utility of webDMDX for masked priming experiments as well as for other time-sensitive methodologies.

As otherwise healthy adults age, their performance on cognitive tests tends to decline. This change is traditionally taken as evidence that cognitive processing is subject to significant declines in healthy aging. We examine this claim, showing current theories over-estimate the evidence in support of it, and demonstrating that when properly evaluated, the empirical record often indicates that the opposite is true. To explain the disparity between the evidence and current theories, we show how the models of learning assumed in aging research are incapable of capturing even the most basic of empirical facts of “associative” learning, and lend themselves to spurious discoveries of “cognitive decline.” Once a more accurate model of learning is introduced, we demonstrate that far from declining, the accuracy of older adults lexical processing appears to improve continuously across the lifespan. We further identify other measures on which performance does not decline with age, and show how these different patterns of performance fit within an overall framework of learning. Finally, we consider the implications of our demonstrations of continuous and consistent learning performance throughout adulthood for our understanding of the changes in underlying brain morphology that occur during the course of cognitive development across the lifespan.