Possible words and fixed stress in the segmentation of Slovak speech

The possible-word constraint (PWC; Norris, McQueen, Cutler, & Butterfield, 1997) has been proposed as a language-universal segmentation principle: Lexical candidates are disfavoured if the resulting segmentation of continuous speech leads to vowelless residues in the input—for example, single consonants. Three word-spotting experiments investigated segmentation in Slovak, a language with single-consonant words and fixed stress. In Experiment 1, Slovak listeners detected real words such as ruka “hand” embedded in prepositional-consonant contexts (e.g., /gruka/) faster than those in nonprepositional-consonant contexts (e.g., /truka/) and slowest in syllable contexts (e.g., /dugruka/). The second experiment controlled for effects of stress. Responses were still fastest in prepositional-consonant contexts, but were now slowest in nonprepositional-consonant contexts. In Experiment 3, the lexical and syllabic status of the contexts was manipulated. Responses were again slowest in nonprepositional-consonant contexts but equally fast in prepositional-consonant, prepositional-vowel, and nonprepositional-vowel contexts. These results suggest that Slovak listeners use fixed stress and the PWC to segment speech, but that single consonants that can be words have a special status in Slovak segmentation. Knowledge about what constitutes a phonologically acceptable word in a given language therefore determines whether vowelless stretches of speech are or are not treated as acceptable parts of the lexical parse.     

Universality versus language-specificity in listening to running speech

Recognizing spoken language involves automatic activation of multiple candidate words. The process of selection between candidates is made more efficient by inhibition of embedded words (like egg in beg) that leave a portion of the input stranded (here, b). Results from European languages suggest that this inhibition occurs when consonants are stranded but not when syllables are stranded. The reason why leftover syllables do not lead to inhibition could be that in principle they might themselves be words; in European languages, a syllable can be a word. In Sesotho (a Bantu language), however, a single syllable cannot be a word. We report that in Sesotho, word recognition is inhibited by stranded consonants, but stranded monosyllables produce no more difficulty than stranded bisyllables (which could be Sesotho words). This finding suggests that the viability constraint which inhibits spurious embedded word candidates is not sensitive to language-specific word structure, but is universal.     

Data from Russian Help to Determine in Which Languages the Possible Word Constraint Applies

The Possible Word Constraint, or PWC, is a speech segmentation principle prohibiting to postulate word boundaries if a remaining segment contains only consonants. The PWC was initially formulated for English where all words contain a vowel and claimed to hold universally after being confirmed for various other languages. However, it is crucial to look at languages that allow for words without vowels. Two such languages have been tested: data from Slovak were compatible with the PWC, while data from Tarifiyt Berber did not support it. We hypothesize that the fixed word stress could influence the results in Slovak and report two word-spotting experiments on Russian, which has similar one-consonant words, but flexible word stress. The results contradict the PWC, so we suggest that it does not operate in the languages where words without vowels are possible, while the results from Slovak might be explained by its prosodic properties.     

Tracking recognition of spoken words by tracking looks to printed words

Eye movements of Dutch participants were tracked as they looked at arrays of four words on a computer screen and followed spoken instructions (e.g., “Klik op het woord buffel”: Click on the word buffalo). The arrays included the target (e.g., buffel), a phonological competitor (e.g., buffer, buffer), and two unrelated distractors. Targets were monosyllabic or bisyllabic, and competitors mismatched targets only on either their onset or offset phoneme and only by one distinctive feature. Participants looked at competitors more than at distractors, but this effect was much stronger for offset-mismatch than onset-mismatch competitors. Fixations to competitors started to decrease as soon as phonetic evidence disfavouring those competitors could influence behaviour. These results confirm that listeners continuously update their interpretation of words as the evidence in the speech signal unfolds and hence establish the viability of the methodology of using eye movements to arrays of printed words to track spoken-word recognition.     

Tracking recognition of spoken words by tracking looks to printed words

Eye movements of Dutch participants were tracked as they looked at arrays of four words on a computer screen and followed spoken instructions (e.g., “Klik op het woord buffel”: Click on the word buffalo). The arrays included the target (e.g., buffel), a phonological competitor (e.g., buffer, buffer), and two unrelated distractors. Targets were monosyllabic or bisyllabic, and competitors mismatched targets only on either their onset or offset phoneme and only by one distinctive feature. Participants looked at competitors more than at distractors, but this effect was much stronger for offset-mismatch than onset-mismatch competitors. Fixations to competitors started to decrease as soon as phonetic evidence disfavouring those competitors could influence behaviour. These results confirm that listeners continuously update their interpretation of words as the evidence in the speech signal unfolds and hence establish the viability of the methodology of using eye movements to arrays of printed words to track spoken-word recognition.     

On the Nature of Semantic Constraints on Lexical Access

We present two eye-tracking experiments that investigate lexical frequency and semantic context constraints in spoken-word recognition in German. In both experiments, the pivotal words were pairs of nouns overlapping at onset but varying in lexical frequency. In Experiment 1, German listeners showed an expected frequency bias towards high-frequency competitors (e.g., Blume, 'flower') when instructed to click on low-frequency targets (e.g., Bluse, 'blouse'). In Experiment 2, semantically constraining context increased the availability of appropriate low-frequency target words prior to word onset, but did not influence the availability of semantically inappropriate high-frequency competitors at the same time. Immediately after target word onset, however, the activation of high-frequency competitors was reduced in semantically constraining sentences, but still exceeded that of unrelated distractor words significantly. The results suggest that (1) semantic context acts to downgrade activation of inappropriate competitors rather than to exclude them from competition, and (2) semantic context influences spoken-word recognition, over and above anticipation of upcoming referents.     

Influence of onset density on spoken-word recognition

Previous research has suggested that the initial portion of a word activates similar sounding words that compete for recognition. Other research has shown that the number of similar sounding words that are activated influences the speed and accuracy of recognition. Words with few neighbors are processed more quickly and accurately than words with many neighbors. The influences of the number of lexical competitors in the initial part of the word were examined in a shadowing and a lexical-decision task. Target words with few neighbors that share the initial phoneme were responded to more quickly than target words with many neighbors that share the initial phoneme. The implications of onset-density effects for models of spoken-word recognition are discussed.     

Learning to use words: Event-related potentials index single-shot contextual word learning

Humans have the remarkable capacity to learn words from a single instance. The goal of this study was to examine the impact of initial learning context on the understanding of novel word usage using event-related brain potentials. Participants saw known and unknown words in strongly or weakly constraining sentence contexts. After each sentence context, word usage knowledge was assessed via plausibility ratings of these words as the objects of transitive verbs. Plausibility effects were observed in the N400 component to the verb only when the upcoming novel word object had initially appeared in a strongly constraining context. These results demonstrate that rapid word learning is modulated by contextual constraint and reveal a rapid mental process that is sensitive to novel word usage.     

In search of perceptual influences of sentence context on word recognition

A major issue in the study of word perception concerns the nature (perceptual or nonperceptual) of sentence context effects. The authors compared effects of legal, word replacement, nonword replacement, and transposed contexts on target word performance using the Reicher-Wheeler task to suppress nonperceptual influences of contextual and lexical constraint. Experiment 1 showed superior target word performance for legal (e.g., "it began to flap/flop") over all other contexts and for transposed over word replacement and nonword replacement contexts. Experiment 2 replicated these findings with higher constraint contexts (e.g., "the cellar is dark/dank") and Experiment 3 showed that strong constraint contexts improved performance for congruent (e.g., "born to be wild") but not incongruent (e.g., mild) target words. These findings support the view that the very perception of words can be enhanced when words are presented in legal sentence contexts.     

The locus of the effects of sentential-semantic context in spoken-word processing

Models of word recognition differ with respect to where the effects of sentential-semantic context are to be located. Using a crossmodal priming technique, this research investigated the availability of lexical entries as a function of stimulus information and contextual constraint. To investigate the exact locus of the effects of sentential contexts, probes that were associatively related to contextually appropriate and inappropriate words were presented at various positions before and concurrent with the spoken word. The results show that sentential contexts do not preselect a set of contextually appropriate words before any sensory information about the spoken word is available. Moreover, during lexical access, defined here as the initial contact with lexical entries and their semantic and syntactic properties, both contextually appropriate and inappropriate words are activated. Contextual effects are located after lexical access, at a point in time during word processing where the sensory input by itself is still insufficiently informative to disambiguate between the activated entries. This suggests that sentential-semantic contexts have their effects during the process of selecting one of the activated candidates for recognition.     

Context length and reading novel words: An eye‐movement investigation

The current study investigated the effects of context length on the processing of novel words. Participants read real adjectives or novel words embedded in either sentence or paragraph contexts while their eye movements were recorded. The results extend the literature on novel word reading by exploring the time‐course of word processing using realistic contexts derived from existing sources. Eye‐movement measures demonstrated that readers were very sensitive to the presence of novel words. Novel words were more likely to be fixated and had longer reading times than real words. In addition, words in sentence contexts had longer gaze durations than words in paragraphs. The effect of novelty on reading the target word did not vary as a function of the context length. While performance on the surprise post‐test did not demonstrate significant word learning, participants did report higher confidence in correct responses than incorrect, suggesting that some learning took place.     

Rated age-of-acquisition norms for over 3,200 German words

Words that have been learned early in life are responded to faster than words that have been acquired later. Subjective ratings of acquisition ages have been successfully employed to study the effect of age of acquisition (AoA). Although a large number of norms exist in many languages, fewer are available for German. Therefore, subjective AoA ratings for 3,259 German words were collected online, including 2,363 nouns and 473 verbs. These words were presented in lists of 140 words, and participants rated the age in years at which they had first learned each word. A split-half correlation testified to a high internal reliability. There were also high correlations with rated AoA values for subsets of the items that had been collected in previous studies, in both German and English. Age and gender were found to influence the ratings very weakly, in that older and male participants tended to give slightly higher age ratings. Education, multilingualism, and frequent usage of languages other than German did not exert an influence on the rating values. These new ratings will extend the currently existing norms available for language and reading research across languages and will provide researchers with a wider choice of word stimuli. The ratings are available expressed in two measurements: age in years, and AoA rated on a 7-point Likert scale.     

Affective orientation influences memory for emotional and neutral words

Memory is better for emotional words than for neutral words, but the conditions contributing to emotional memory improvement are not entirely understood. Elsewhere, it has been observed that retrieval of a word is easier when its attributes are congruent with a property assessed during an earlier judgment task. The present study examined whether affective assessment of a word matters to its remembrance. Two experiments were run, one in which only valence assessment was performed, and another in which valence assessment was combined with a running recognition for list words. In both experiments, some participants judged whether each word in a randomized list was negative (negative monitoring), and others judged whether each was positive (positive monitoring). We then tested their explicit memory for the words via both free recall and delayed recognition. Both experiments revealed an affective congruence effect, such that negative words were more likely to be recalled and recognized after negative monitoring, whereas positive words likewise benefited from positive monitoring. Memory for neutral words was better after negative monitoring than positive monitoring.Thus, memory for both emotional and neutral words is contingent on one's affective orientation during encoding.     

The neural basis of obligatory decomposition of suffixed words

Recent neurolinguistic studies present somewhat conflicting evidence concerning the role of the inferior temporal cortex (IT) in visual word recognition within the first 200 ms after presentation. On the one hand, fMRI studies of the Visual Word Form Area (VWFA) suggest that the IT might recover representations of the orthographic form of words. On the other hand, influential MEG studies of responses from the occipito-temporal regions around 150 ms post-stimulus onset indicate recognition of letters as opposed to symbols but not a sensitivity to statistical properties of letter strings associated with word form representations. Recent MEG experiments support the position that the IT does represent the visual word forms of morphemes and performs morphological decomposition modulated by the statistical relations between morphemes by 170 ms post presentation (at the M170 response). Responses to heteronyms show that the M170 does not make contact with the mental lexicon where word forms are connected to meanings. We report here an MEG study of pseudo-affixed words like brother, which masked priming studies have shown are decomposed in recognition. If the M170 response from IT does index obligatory morphological decomposition based on visual word forms but not lexical entries, we should find that the statistical relation between pseudo-stem and pseudo-suffix modulates the M170 for pseudo-affixed words, as for truly affixed words. The results of this experiment confirm this prediction. In addition, surface form frequency for these words also modulates the M170, providing some support for dual route recognition for words for which decomposition is a garden path.     

When Words Compete: Levels of Processing in Perception of Spoken Words

Current theories of spoken-word recognition posit two levels of representation and process: lexical and sublexical. By manipulating probabilistic phonotactics and similarity-neighborhood density, we attempted to determine if these two levels of representation have dissociable effects on processing. Whereas probabilistic phonotactics have been associated with facilitatory effects on recognition, increases in similarity-neighborhood density typically result in inhibitory effects on recognition arising from lexical competition. Our results demonstrated that when the lexical level is invoked using real words, competitive effects of neighborhood density are observed. However, when strong lexical effects are removed by the use of nonsense word stimuli, facilitatory effects of phonotactics emerge. These results are consistent with a two-level framework of process and representation embodied in certain current models of spoken-word recognition.     

The interpretation of ambiguous trimorphemic words in sentence context

Many trimorphemic words are structurally and semantically ambiguous. For example, unlock-able can either be un-lockable (cannot be locked) or unlock-able (can be unlocked). Which interpretation is preferred and whether the preceding sentence context affects the initial interpretation is not clear from prior research. The present experiment embedded ambiguous trimorphemic words in sentence contexts, manipulated whether or not preceding context disambiguated the meaning, and examined the pattern of fixation durations on the ambiguous word and the remainder of the text. The results indicated that the unlock-able interpretation was preferred; moreover, preceding context did not exert a significant effect until the eyes had initially exited from the target word.     

The role of the ventral and dorsal pathways in reading Chinese characters and English words

Previous literature in alphabetic languages suggests that the occipital-temporal region (the ventral pathway) is specialized for automatic parallel word recognition, whereas the parietal region (the dorsal pathway) is specialized for serial letter-by-letter reading ( [Cohen et al., 2008] and [Ho et al., 2002] ). However, few studies have directly examined the role of the ventral and dorsal pathways in Chinese reading compared to English reading. To investigate this issue, we adopted the degraded word processing paradigm used by Cohen et al. (2008) and compared brain regions involved in the processing of degraded Chinese characters and English words during lexical decision, using functional magnetic resonance imaging (fMRI). The degraded characters/words were created by inserting blank spaces between radicals of Chinese characters or syllables of English polysyllabic words. Generally, the current study replicated the effects of Cohen et al. (2008), showing that in Chinese – like in alphabetic languages – character spacing modulates both ventral (bilateral cuneus, left middle occipital gyrus) and dorsal (left superior parietal lobule and middle frontal gyrus) pathways. In addition, the current study showed greater activation in bilateral cuneus and right lingual gyrus for Chinese versus English when comparing spaced to normal stimuli, suggesting that Chinese character recognition relies more on ventral visual-spatial processing than English word recognition. Interestingly, bilateral cuneus showed monotonic patterns in response to increasing spacing, while the rest of the regions of interest showed non-monotonic patterns, indicating different profiles for these regions in visual-spatial processing.     

Asymmetric Reinstatement Effects in Recognition

Our experiment examined two questions: (1) Does reinstating a studied context affect recognition of an associated word, and (2) Does reinstating a studied word affect recognition of an associated context? After encoding 75 words, each of which was shown superimposed over a different 5-sec video of an environment (e.g., a playground, a traffic scene, or a grocery store), participants were asked to recognize 50 of the words and 50 of the video scenes. On the test, half of the studied words were shown superimposed over the same video contexts that had been present at encoding, and half were shown over new scenes. Similarly, videos were presented with either old or new words. Context reinstatement increased hits and reduced false alarms for words, but word reinstatement did not affect recognition of video contexts. The results suggest that the associations that bind word events with their contexts may not be bidirectional.     

On the segmentation of Chinese words during reading

Given that there are no spaces between words in Chinese, how words are segmented when reading is something of a mystery. Four Chinese characters, which either constituted one 4-character word or two 2-character words, were shown briefly to subjects. Subjects were quite accurate in reporting the 4-character word, but could usually only report the first 2-character word, demonstrating that word segmentation influences character recognition. The results suggest that even with these simple 4-character strings, there is an element of seriality in reading Chinese words: processing is initially focused at least to some extent on the first word. We also found that the processing of characters that are not consistent with the context is inhibited, suggesting inhibition from word representations to character representations. A simple model of Chinese word segmentation and word recognition is presented to account for the data.     

Effects of chronic non-clinical depression on the use of positive and negative words in language contexts

The purpose of this study was to investigate the effects of chronic non-clinical depression (ChD) on the use of ambiguous and unambiguous emotional words in language contexts. Participants with ChD and normal non-depressed (ND) participants' responses to positive and negative stimulus words on a free association word test were compared using the Hyperspace Analogue to Language (HAL) model of memory's context density metric, a measure of the range of contexts in which a word is used in language. ChD participants generated negative words that were used in more restricted contexts than ND participants. However, ND and ChD participants used positive words in a similar range of contexts. The results suggest that people with ChD tend to use negative words that are probably more negative in connotation, yet they are not impaired with respect to using words in contexts where positive words are required.