SpaVerb-WN—A megastudy of naming times for 4562 Spanish verbs: Effects of psycholinguistic and motor content variables

Several studies have been carried out in various languages to explore the role of the main psycholinguistic variables in word naming, mainly in nouns. However, reading of verbs has not been explored to the same extent, despite the differences that have been found between the processing of nouns and verbs. To reduce this research gap, we present here SpaVerb-WN, a megastudy of word naming in Spanish, with response times (RT) for 4562 verbs. RT were obtained from at least 20 healthy adult participants in a reading-aloud task. Several research questions on the role of syllable frequency, word length, neighbourhood, frequency, age of acquisition (AoA), and the novel variable ‘motor content’ in verb naming were also examined. Linear mixed-effects model analyses indicated that (1) RT increase in with increasing word length and with decreasing neighbourhood size, (2) syllable frequency does not show a significant effect on RT, (3) AoA mediates the effect of motor content, with a positive slope of motor content at low AoA scores and a negative slope at high AoA scores, and (4) there is an interaction between word frequency and AoA, in which the AoA effect for low-frequency verbs gradually decreases as frequency increases. The results are discussed in relation to existing evidence and in the context of the consistency of the spelling–sound mappings in Spanish.

Inhibitory effect of positional syllable frequency in Spanish 2nd and 4th grade readers

The inhibitory effect of positional syllable frequency is a well-known phenomenon in visual word recognition: words with high-frequency syllables require extra time for deactivating the lexical syllabic neighbors. The inhibitory effect implies that a connection exists between graphemes, phonemes, the first syllable, and the phonological lexicon. However, experimental results of the first developmental stages of occurrence are scarce and inconclusive. A second- and fourth-grade sample of typical school readers participated in a lexical decision task containing high/low frequency words and high/low syllable frequency words. Our primary hypothesis was that the inhibitory effect would be found on both school grade groups. We did not predict significant differences in magnitude of effect between second- and fourth-grade participants. A general inhibitory effect was found, and separate analyses by school grade groups also indicated significant inhibitory effects. Furthermore, second- and fourth-grade children showed small sizes of the inhibitory effect, resembling the sizes found in adult normal readers. Our results suggest that Spanish readers reach a functional connection between syllables and words at an early stage. The straightforward theoretical implication is that the inhibitory effect relies heavily on the structural properties of the lexical access system that are acquired at an early age.

Spans attributed to short-term memory are explained by sensitivity to long-term statistics in both musicians and individuals with dyslexia

Reduced short-term memory (STM) of individuals with dyslexia (IDDs) and enhanced STM of musicians are well documented, yet their causes are disputed. We hypothesized that their STMs reflect their sensitivities to accumulative long-term stimuli statistics. Indeed, when performing an STM task, IDDs had reduced benefit from syllable frequency, whereas musicians manifested an opposite effect, compared to controls. Interestingly, benefit from sequence-repetition did not significantly differ between groups, suggesting that it relies on different mechanisms. To test the generality of this separation across populations, we recruited a group of good-readers, whose native language contains a smaller fraction of the high-frequency syllables. Their span for these “high-frequency” syllables was small, yet their benefit from sequence-repetition was adequate. These experiments indicate that sensitivity to long-term stimuli distribution, and not to sequential repetition, is reduced in IDDs and enhanced in musicians, and this accounts for differences in their STM performance.

Supervised Ensemble Learning for Vietnamese Tokenization

Vietnamese tokenization is a challenging basic issue, and the corresponding algorithms can be used in many applications of natural language processing. In this paper, we investigate the Vietnamese tokenization problem and propose a supervised ensemble learning (SEL) framework as well as a SEL-based tokenization (SELT) algorithm. Supported by the data structure of syllable-syllable frequency index, the SELT algorithm combines multiple weak tokenizers to form a strong tokenizer. Within the SEL framework, we also investigate the efficient construction problem of a weak tokenizer. We suggest two prediction methods to select a suitable dictionary, and efficiently implement two weak tokenizers by the simple dictionary-based tokenization algorithm. The experimental results show that the SELT algorithm integrating our weak tokenizers can achieve state-of-the-art performance in the Vietnamese tokenization task.