Novel word integration in the mental lexicon: Evidence from unmasked and masked semantic priming

We sought to establish whether novel words can become integrated into existing semantic networks by teaching participants new meaningful words and then using these new words as primes in two semantic priming experiments, in which participants carried out a lexical decision task to familiar words. Importantly, at no point in training did the novel words co-occur with the familiar words that served as targets in the primed lexical decision task, allowing us to evaluate semantic priming in the absence of direct association. We found that familiar words were primed by the newly related novel words, both when the novel word prime was unmasked (Experiment 1) and when it was masked (Experiment 2), suggesting that the new words had been integrated into semantic memory. Furthermore, this integration was strongest after a 1-week delay and was independent of explicit recall of the novel word meanings: Forgetting of meanings did not attenuate priming. We argue that even after brief training, newly learned words become an integrated part of the adult mental lexicon rather than being episodically represented separately from the lexicon.     

Lexical stress,frequency, and stress neighbourhood effects in the early stages of Italian reading development

We examined the development of stress assignment in reading Italian aloud. We investigated frequency effects as a marker of the use of item-specific lexical knowledge in assigning stress together with stress dominance and stress neighbourhood (the number of words sharing both stress and ending) as markers of distributional information regarding properties of the lexicon extracted from spoken language. We tested second- and fourth-graders in a reading-aloud experiment including high- and low-frequency words and nonwords. Results show that despite the regularity of orthography–phonology mappings in Italian and the predominant use of phonological recoding procedures, item-specific lexical knowledge is also used, even by beginning readers. The frequency effect was significant and did not increase with age, while stress errors on low-frequency words decreased with increasing grade. Stress neighbourhood increasingly affected stress assignment on nonwords with older children. Taken together, our findings show that both item-specific knowledge and general information about stress distribution are relevant in children's reading, suggesting the simultaneous use of both lexical and sublexical information. Moreover, as the reading system develops, and knowledge about the relative distribution of stress neighbourhood increases, larger grain-size units are also exploited.     

SUBTLEX-UK: A new and improved word frequency database for British English

We present word frequencies based on subtitles of British television programmes. We show that the SUBTLEX-UK word frequencies explain more of the variance in the lexical decision times of the British Lexicon Project than the word frequencies based on the British National Corpus and the SUBTLEX-US frequencies. In addition to the word form frequencies, we also present measures of contextual diversity part-of-speech specific word frequencies, word frequencies in children programmes, and word bigram frequencies, giving researchers of British English access to the full range of norms recently made available for other languages. Finally, we introduce a new measure of word frequency, the Zipf scale, which we hope will stop the current misunderstandings of the word frequency effect.     

Picture–word interference reveals inhibitory effects of syllable frequency on lexical selection

While previous research has shown that high syllable frequency can facilitate speech production at the level of phonological/phonetic encoding, little is known about its influence on prephonological processes, specifically lexical selection. The current study used a picture–word interference (PWI) task to (a) shed light on the stages of lexical access where syllable frequency is relevant, and (b) inform as to whether lexical selection is accomplished via competition among activated word options. Participants named pictures whose names had high-frequency (HF) and low-frequency (LF) first syllables while ignoring phonologically related (same first syllable) or unrelated distractor words that were presented simultaneously. Word frequency was also manipulated, as half of the targets were HF words, and half were LF words. Results revealed inhibitory syllable frequency effects in all conditions, such that targets with HF first syllables were named more slowly than targets with LF first syllables. However, inhibitory syllable frequency effects were exacerbated in conditions thought to reflect heightened lexical competition, specifically in the presence of phonologically related distractors and for targets with low word frequency. These findings reveal novel evidence for first-syllable frequency effects on lexical selection and offer further support for models proposing delays at lexical selection due to activation of nontarget competitors.     

On the advantages of word frequency and contextual diversity measures extracted from subtitles: The case of Portuguese

We examined the potential advantage of the lexical databases using subtitles and present SUBTLEX-PT, a new lexical database for 132,710 Portuguese words obtained from a 78 million corpus based on film and television series subtitles, offering word frequency and contextual diversity measures. Additionally we validated SUBTLEX-PT with a lexical decision study involving 1920 Portuguese words (and 1920 nonwords) with different lengths in letters (M?=?6.89, SD?=?2.10) and syllables (M?=?2.99, SD?=?0.94). Multiple regression analyses on latency and accuracy data were conducted to compare the proportion of variance explained by the Portuguese subtitle word frequency measures with that accounted by the recent written-word frequency database (Procura-PALavras; P-PAL; Soares, Iriarte, et al., 2014 Soares, A. P., Iriarte, A., Almeida, J. J., Simões, A., Costa, A., França, P.,?… Comesaña, M. (2014). Procura-PALavras (P-PAL): Uma nova medida de frequência lexical do Português Europeu contemporâneo [Procura-PALavras (P-PAL): A new measure of word frequency for contemporary European Portuguese]. Psicologia: Reflexão e Crítica, 27, 110–123.[Crossref] , [Google Scholar]). As its international counterparts, SUBTLEX-PT explains approximately 15% more of the variance in the lexical decision performance of young adults than the P-PAL database. Moreover, in line with recent studies, contextual diversity accounted for approximately 2% more of the variance in participants' reading performance than the raw frequency counts obtained from subtitles. SUBTLEX-PT is freely available for research purposes (at http://p-pal.di.uminho.pt/about/databases).     

Morphological learning in a novel language: A cross-language comparison

Being able to extract and interpret the internal structure of complex word forms such as the English word dance+r+s is crucial for successful language learning. We examined whether the ability to extract morphological information during word learning is affected by the morphological features of one's native tongue. Spanish and Finnish adult participants performed a word–picture associative learning task in an artificial language where the target words included a suffix marking the gender of the corresponding animate object. The short exposure phase was followed by a word recognition task and a generalization task for the suffix. The participants' native tongues vary greatly in terms of morphological structure, leading to two opposing hypotheses. On the one hand, Spanish speakers may be more effective in identifying gender in a novel language because this feature is present in Spanish but not in Finnish. On the other hand, Finnish speakers may have an advantage as the abundance of bound morphemes in their language calls for continuous morphological decomposition. The results support the latter alternative, suggesting that lifelong experience on morphological decomposition provides an advantage in novel morphological learning.     

On the relationship between visual imagery and visual perception: Evidence from priming studies

Two priming experiments using a perceptual identification task were conducted to explore the functional and representational overlap between visual imagery and visual perception. The first experiment included a study phase in which primes were either perceived or imaged objects and a perceptual identification test task in which targets were parts of studied and non-studied objects. Imagery primed identification when subjects were instructed to count the parts of the imaged objects in the study phase but not when they were instructed to focus on the global shape of the imaged objects. This result suggests that imagery involves perceptual representations identical to those involved in perception. It also suggests that the representational overlap between imagery and perception depends on the type of images generated, as some images may consist in global shapes only, whereas others may consist in detailed, multi-part shapes. In the second experiment, we used whole objects as target stimuli which provided subjects with more information to identify masked targets and thereby reduced top-down processing. Priming from imagery fell beneath significance, suggesting that this sort of priming is elicited in a large part by a transfer of top-down processes from study to test.     

The focus of attention in working memory: Evidence from a word updating task

Three experiments examined the cognitive costs of item switching within working memory with a novel word updating task, thereby extending previous research to the field of linguistic stimuli and linguistic-graphemic updating operations. In Experiments 1 and 2 costs for switching between working memory items were evident on the word level, and they increased with an increasing word set size (Experiment 2). In contrast, a surprisingly similar switch effect on the level of letters was not affected by word set size (Experiment 2). Experiment 3 showed that this effect is not simply based on the need for re-orienting visual spatial attention. To account for the overall picture of results, a recursive model of attentional foci is proposed. Moreover, individual working memory span appears to be associated with the accuracy of item switching, but not with its speed.     

Enhancing the learning of new words using an errorless learning procedure: Evidence from typical adults

Two experiments compared the efficacy of errorless and errorful training procedures in the acquisition of novel words in typical adults. One experiment involved learning novel names for novel objects, while a second involved learning obscure English words and their definitions. In both studies the errorless method led to significantly better learning as assessed by an immediate cued recall test. The errorless advantage was characterised by a reduction in extra-experimental intrusion errors and was still present when learning was re-tested 3–4 days after training. In contrast there was no errorless advantage in recognition of word-to-object pairings. Taken together, these results suggest that errorless learning procedures improve retrieval by leading to the creation of better-specified, retrievable representations in long-term memory.     

Searching for the Right Word: Performance on Four Word-Retrieval Tasks Across Childhood

Word retrieval was assessed in 207 normally developing Hebrew-speaking children aged 8–17 through four tasks: picture naming, phonemic fluency, semantic fluency, and homophone meaning generation (HMGT). Scores on all tests correlated positively and significantly with participant age. Yet, age effects and the correlation between age and test scores were weakest for the naming test and strongest for the HMGT. We discuss the nature of the word search involved in each task and suggest that the more executive demands required by a test the steeper the slope of performance increase on this test.