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The adult human visual system maintains the ability to be altered by sensory deprivation. What has not been considered is whether the internal neural states modulate visual sensitivity to short-term monocular deprivation. In this study we manipulated the internal neural state and reported changes in intrinsic neural oscillations with a patched eye open or closed. We investigated the influence of eye open/eye closure on the unpatched eye’s contrast sensitivity and ocular dominance (OD) shifts induced by short-term monocular deprivation. The results demonstrate that internal neural states influence not only baseline contrast sensitivity but also the extent to which the adult visual system can undergo changes in ocular dominance.

The adult human visual system can exhibit a degree of neuroplastic change under the right conditions which has implications for future treatments to recover vision loss that have occurred in infancy. The exogenous factors that promote neuroplastic change have been the focus of human psychophysical, electrophysiological and neuroimaging research over the last decade. What has not been considered is the importance of endogenous factors. In this study we modulate the neural oscillations that determines the internal neural state to demonstrate that endogenous factors play a critical role in not only baseline contrast sensitivity but also the extent to which the adult visual system can undergo neuroplastic change in binocular balance.

Recent studies indicate that short-term monocular deprivation increases the deprived eye's contribution to binocular fusion in both adults with normal vision and amblyopia. In this study, we investigated whether the changes in visual plasticity depended on the duration of deprivation in normal and amblyopic adults.Twelve anisometropia amblyopic observers (aged 24.8 ± 2.3 years) and 12 age-matched normal observers (aged 23.9 ± 1.2 years) participated in the study. The non-dominant eye of normal observers or amblyopic eye of amblyopic observers was deprived for 30, 120, and 300 min in a randomized order. Their eye balance was measured with a phase combination task, which is a psychophysical test, before and after the deprivation. This design enabled us to measure changes induced in binocular balance as an index visual plasticity due to monocular deprivations.By comparing the ocular dominance changes as a result of monocular deprivation with different deprivation durations, we found evidence that the ocular dominance changes are slightly larger after longer deprivations in both normal and amblyopic observers, albeit with a statistical significance. The changes from 120-min were significantly greater than those from 30-min deprivation in both groups. The magnitude of changes in sensory eye balance was significantly larger in normal observers than that in the amblyopic observers; however, the longevity of changes in visual plasticity was found to be more long-lasting in amblyopic observers than the normal counterparts.The duration of deprivation matters in both normal and amblyopic observers. Ocular dominance imbalance that is typically observed in amblyopia can be more ameliorated with a longer duration of deprivation.

Musical expertise is known to affect speech perception at units below clause/sentence. This study investigated whether the musician's advantage extends to a higher and more central level of speech processing (i.e., clause segmentation). Two groups of participants (musician vs. nonmusician) were presented with sentences that contain an internal clause boundary. The acoustic correlates of the boundary were manipulated in six conditions: all-cue, pause-only, final-lengthening-only, pitch-reset-only, pause-and-final-lengthening-in-combination, and no-cue conditions. Participants were asked to judge whether the sentence they heard had an internal boundary. Results showed that the musicians detected more boundaries than the nonmusicians in the all-cue and the pause-only conditions, but fewer boundaries in the no-cue condition. Further analyses of cue weight showed that both musicians and nonmusicians placed more importance on pause than the other two cues, but this weighting bias was more pronounced for the musicians. These results suggest that music training is associated with increased perceptual acuity not only to the acoustic markings of speech boundaries but also to the weighting of the cues. Our findings extend the role of musical expertise to sentence-level speech processing.

Purpose We developed a stereo task that is based on a motion direction discrimination to examine the role that depth can play in disambiguating motion direction. Methods In this study, we quantified normal adults’ static and dynamic (i.e., laterally moving) stereoscopic performance using a psychophysical task, where we dichoptically presented randomly arranged, limited lifetime Gabor elements at two depth planes (one plane was at the fixation plane and the other at an uncrossed disparity relative to the fixation plane). Each plane contained half of the elements. For the dynamic condition, all elements were vertically oriented and moved to the left in one plane and to the right in another plane; for the static condition, the elements were horizontally oriented in one plane and vertically oriented in another plane. Results For the range of motion speed that we measured (from 0.17°/s to 5.33°/s), we observed clear speed tuning of the stereo sensitivity (P = 3.0 × 10−5). The shape of this tuning did not significantly change with different spatial frequencies. We also found a significant difference in stereo sensitivity between stereopsis with static and laterally moving stimuli (speed = 0.67°/s; P = 0.004). Such difference was not evident when we matched the task between the static and moving stimuli. Conclusions We report that lateral motion modulates human global depth perception. This motion/stereo constraint is related to motion velocity not stimulus temporal frequency. We speculate that the processing of motion-based stereopsis of the kind reported here occurs in dorsal extrastriate cortex.

Most of the world’s languages use both segment and lexical tone to distinguish word meanings. However, the few studies on spoken word recognition in tone languages show conflicting results concerning the relative contribution of (sub-)syllabic constituents, and the time course of how segmental and tonal information is utilised. In Experiments 1 & 2, participants listened to monosyllabic Mandarin words with the presence of a phonological competitor, which overlaps in either segmental syllable, onset and tone, rhyme and tone, or just tone. Eye movement results only confirmed the segmental syllable competition effect. Experiment 3 investigated the time course of segmental vs. tonal cue utilisation by manipulating their point of divergence (POD) and found that POD modulates the look trajectories of both segmental and tonal phonological competitors. While listeners can use both segmental and tonal information incrementally to constrain lexical activation, segmental syllable plays an advantageous role in Mandarin spoken word recognition.

Pronunciation of words or morphemes may vary systematically in different phonological contexts, but it remains unclear how different levels of phonological information are encoded in speech production. In this study, we investigated the online planning process of Mandarin Tone 3 (T3) sandhi, a case of phonological alternation whereby a low-dipping tone (T3) changes to a Tone 2 (T2)-like rising tone when followed by another T3. To examine the time course of the encoding of the abstract category-level (underlying form) and context-specific phonological form (surface form) of T3, we conducted an electroencephalographic (EEG) study with a phonologically-primed picture naming task and examined the event-related potentials (ERPs) time-locked to the stimulus onset as well as speech response onset. The behavioral results showed that targets primed by T3 or T2 primes yielded shorter naming latencies than those primed by control primes. Importantly, the EEG data revealed that T3 primes elicited larger positive amplitude over broad frontocentral regions roughly in the 320-550 ms time window of stimulus-locked ERP and -500 to -400 ms time window of response-locked ERP, whereas T2 primes elicited larger negative amplitude over left frontocentral regions roughly in the -240 to -100 ms time window of response-locked ERP. These results indicate that the underlying and the surface form are encoded at different processing stages. The former presumably occurs in the earlier phonological encoding stage, while the latter probably occurs in the later phonetic encoding or motor preparation stage. The current study offers important implications for understanding the processing of phonological alternations and tonal encoding in Chinese word production.

While prosodic boundaries are known to affect the acoustic realization of segments and lexical full tones, no study thus far has examined how the f0 realization of a neutral tone is influenced by different prosodic boundaries. This study set out to fill this knowledge gap by investigating the effect of prosodic boundary on neutral-tone realization in Tianjin Mandarin, a variety which has been reported to exhibit interesting context-dependent f0 variation. Our results showed that the high neutral-tone f0 offset before the low falling tone (Tone 1) does not need to be treated as a special tonal target as claimed in the literature, but rather could be due to the raising effect brought about by the following T1, which can also be observed on the f0 realization of lexical tones. The neutral tone in Tianjin Mandarin has a mid-low tonal target similar to that in Standard Chinese. In addition, by manipulating the prosodic boundary between neutral tone and the following T1, we observed an interesting effect of prosodic boundary on the neutral-tone f0 realization. Specifically, the raising effect due to the following T1 can be blocked by a higher-level prosodic boundary (i.e., a Subject-Predicate boundary) compared to a lower-level prosodic boundary (i.e., a Below-NP boundary). Finally, our study observed both effects of prosodic boundary and focus on tonal implementation. They remain separate mechanisms in speech production, but could interact to modulate the magnitude of f0 changes due to effects of focus and prosodic boundary in neutral-tone f0 realization.

In tonal languages such as Mandarin, both lexical tone and sentence intonation are primarily signaled by F0. Their F0 encodings are sometimes in conflict and sometimes in congruency. The present study investigated how tone and intonation, with F0 encodings in conflict or in congruency, are processed and how semantic context may affect their processing. To this end, tone and intonation identification experiments were conducted in both semantically neutral and constraining contexts. Results showed that the overall performance of tone identification was better than that of intonation. Specifically, tone identification was seldom affected by intonation information irrespective of semantic contexts. However, intonation identification, particularly question intonation, was susceptible to the final lexical tone identity and affected by the semantic context. In the semantically neutral context, questions ending with a rising tone and a falling tone were equally difficult to identify. In the semantically constraining context, questions ending with a falling tone were much better identified than those ending with a rising tone. This perceptual asymmetry suggests that top-down information provided by the semantically constraining context can play a facilitating role for listeners to disentangle intonational information from tonal information, but mainly in sentences with the lexical falling tone in the final position.

This chapter provides a summary of the prosodic systems of varieties of Chinese spoken in mainland China and Taiwan as well as languages in Siberia, in particular Ket. What the Chinese languages and Ket share is their tonal nature. This chapter highlights three unique aspects of the prosody of these languages. First, it surveys the typologically complex patterns of tonal alternation known as ‘tone sandhi’ and provides a summary of current experimental findings on the productivity of these patterns. Second, it discusses the patterns of lexical and phrasal stress and their interaction with tone, with a focus on the similar metrical principles that underlie tone languages and other languages. Third, it surveys the different types of interaction between lexical tone and the intonational use of pitch, in particular focus and interrogativity. These issues are first discussed in the context of Chinese languages, then echoed in a brief summary of Ket prosody.

Lili Wu Chinese () is a Wu dialect (; ISO 639-3; code: wuu) spoken by approximately 38,000 people who reside in the town of Lili (), one of the ten major towns in the Wujiang district (). The Wujiang district belongs to the prefectural-level municipality of Suzhou city () in Jiangsu province (), the People’s Republic of China. It is located at the juncture area of the city of Shanghai (), the city of Suzhou, and the city of Jiaxing (), as shown in Figure 1.

Context-based predictions facilitate speech processing. However, details of predictive processing mechanisms and how factors like language experience shape facilitative processing remain debated. This electroencephalograph study aimed to shed light on these issues by investigating the effect of dialectal experience on lexical prediction. Stimulus sentences were produced in three Mandarin Chinese dialects (home dialect, familiar regional dialect, and unfamiliar regional dialect). Critical nouns varied between strong and weak predictability. Only when listening to the home dialect was an enhanced ERP deflection observed at the transitive verb before a strongly predictable object noun (compared to the weakly predictable condition); the ERP amplitude at the verb correlated significantly with the following noun’s predictability. The predictable object nouns elicited a reduced N400 in all three dialects but only an additional reduction in N1 in the home dialect condition. Conjointly, our results suggest that effortful meaning computation may partially underlie anticipatory lexical processing and that language experience modulates the way lexical prediction facilitates the early stage of acoustic/phonological processing (in addition to the later stage of meaning integration).

Purpose: Recently, Lunghi et al showed that amblyopic eye’s visual acuity per se after 2 months of occlusion therapy could be predicted by a homeostatic plasticity, i.e., the temporary shift of perceptual eye dominance observed after a 2-hour monocular deprivation, in children with anisometropic amblyopia(Lunghi et al., 2016). In this study, we assess whether the visual acuity improvement of the amblyopic eye measured after 2 months of occlusion therapy could be predicted by this plasticity. Methods: Seven children (6.86 ± 1.46 years old; SD) with anisometropic amblyopia participated in this study. All patients were newly diagnosed and had no treatment history before participating our study. They finished 2 months of refractive adaptation and then received a 4-hour daily fellow eye patching therapy with an opaque patch for a 2-month period. Best-corrected visual acuity of the amblyopic eye was measured before and after the patching therapy. The homeostatic plasticity was assessed by measuring the temporary shift of perceptual eye dominance from 2-hour occlusion of the amblyopic eye before treatment. A binocular phase combination paradigm was used for this study. Results: We found that there was no significant correlation between the temporary shift of perceptual eye dominance observed after 2-hour occlusion of the amblyopic eye and the improvement in visual acuity in the amblyopic eye from 2-hour of classical patching therapy. This result, although in disagreements with the conclusions of Lunghi et al involving the short-term patching of the amblyopic eye, is in fact consistent with a reanalysis of Lunghi et al’ s data. Conclusions: The short-term changes in perceptual eye dominance as a result of short-term monocular deprivation do not provide an index of cortical plasticity in the general sense such that they are able to predict acuity outcomes from longer term classical patching.

Studies on binocular combination and rivalry show that short-term deprivation strengthens the contribution of the deprived eye in binocular vision. However, whether short-term monocular deprivation affects temporal processing per se is not clear. To address this issue, we conducted a study to investigate the effect of monocular deprivation on dichoptic temporal synchrony. We tested ten adults with normal vision and patched their dominant eye with an opaque patch for 2.5 h. A temporal synchrony paradigm was used to measure if temporal synchrony thresholds change as a result of monocular pattern deprivation. In this paradigm, we displayed two pairs of Gaussian blobs flickering at 1 Hz with either the same or different phased- temporal modulation. In Experiment 1, we obtained the thresholds for detecting temporal asynchrony under dichoptic viewing configurations. We compared the thresholds for temporal synchrony between before and after monocular deprivation and found no significant changes of the interocular synchrony. In Experiment 2, we measured the monocular thresholds for detecting temporal asynchrony. We also found no significant changes of the monocular synchrony of either the patched eye or the unpatched eye. Our findings suggest that short-term monocular deprivation induced-plasticity does not influence monocular or dichoptic temporal synchrony at low temporal frequency.

PurposeRecently, Lunghi et al showed that amblyopic eye’s visual acuity per se after 2 months of occlusion therapy could be predicted by a homeostatic plasticity, i.e., the temporary shift of ocular dominance observed after a 2-hour monocular deprivation, in children with anisometropic amblyopia(Lunghi et al., 2016). In this study, we assess whether the visual acuity improvement of the amblyopic eye measured after 2 months of occlusion therapy could be predicted by this plasticity.MethodsSeven children (6.86 ± 1.46 years old; SD) with anisometropic amblyopia participated in this study. All patients were newly diagnosed and had no treatment history before participating in our study. They had finished 2 months of refractive adaptation and then received a 4-hour daily fellow eye patching therapy with an opaque patch for a 2-month period. Best-corrected visual acuity of the amblyopic eye was measured before and after the patching therapy. The homeostatic plasticity was assessed by measuring the temporary shift of ocular dominance observed after 2 hours of occlusion for the amblyopic eye before the treatment started. A binocular phase combination paradigm was used for this test.ResultsWe found that there was no significant correlation between the temporary shift of ocular dominance observed after 2 hours of occlusion for the amblyopic eye before the treatment started and the visual acuity gain obtained by the amblyopic eye from 2-month of classical patching therapy. This result involving the short-term patching of the amblyopic eye is consistent with a reanalysis of Lunghi et al’ s data.ConclusionsOcular dominance plasticity does not provide an index of cortical plasticity in the general sense such that it could be used to predict acuity outcomes from longer term classical patching.

Purpose: To determine if benefits from occlusion therapy are due to decreased suppression from the fellow eye in children with amblyopia. Methods: Ten newly diagnosed amblyopes (7.2 ± 1.4 years old), two with strabismus and eight with anisometropia, participated. Patients were first given a 2-month period of refractive adaptation, followed by occlusion therapy (i.e., patching their fellow eye with an opaque patch for 4 hours/day). Visual acuity of the amblyopic eye and interocular suppression were measured before and after 0.5, 1, 2, 4 and 6 months of occlusion therapy. We quantified interocular suppression with a binocular phase combination task. Results: Visual acuity (in logMAR) improved from 0.50 ± 0.22 (mean ± SD) to 0.33 ± 0.20 for patients who finished a short-term (two months) occlusion (A1 to A10), from 0.53 ± 0.20 to 0.32 ± 0.22 for patients who finished a medium-term (four months) occlusion (A1 to A9) and from 0.48 ± 0.19 to 0.22 ± 0.10 for patients who finished a long-term (six months) occlusion (A1 to A8). Although their visual acuity significantly improved, their degree of suppression, which was abnormal in all cases, did not change consistently. This was true in all durations of occlusion therapy. Conclusions: Reduced suppression from the fixing eye might not be result from occlusion therapy.

This study examines the acoustic properties concerning tonal split and stop onsets in an under-documented Wu Chinese variety, Lili Wu, using speech production data collected from field research. Lili Wu Chinese has been reported to demonstrate an unusual tonal split phenomenon known as "aspiration-induced tonal split" (ATS). ATS refers to the distinct lowering of f0 of a lexical tone over syllables beginning with a voiceless aspirated obstruent, compared to that of syllables beginning with an unaspirated obstruent. Two debates lingering in the existing literature are discussed: (i) is ATS an on-going change or a completed change? and (ii) is it onset aspiration or vowel breathiness that directly triggers ATS? Results suggest that ATS is a completed change, which, however, is conditioned by tonal contexts. Regarding the second debate, results suggest that neither aspiration nor breathiness serves as the direct trigger for tonal split. Moreover, one unexpected on-going sound change was observed: The breathiness of vowels after voiced onsets seems to be disappearing among the younger generation. These findings extend the understanding of the acoustic properties of tonal development in a complex system and highlight the importance of experimental methods in understanding the sound structure and changes of under-documented languages.

Breathy phonation refers to the laryngeal setting where the vocal folds are less tense and make less contact than in “modal” phonation, which consequently leads to continuous leaking of voiceless airflow, giving rise to the perception of breathiness in a speech sound. In Austronesian languages, contrastive breathy segments are very rare. For the Austronesian languages of Island Southeast Asia, only one language has been reported to have phonemically breathy vowels: Kedang, a language spoken on Lembata island, in eastern Indonesia. In this paper, we revisit the earlier analysis that in Kedang, breathiness distinguishes phonemic “breathy” from “modal” vowels. Presenting evidence of distributional, acoustic, and etymological nature, we argue that the so-called breathy onsetless vowels do not appear to be similar to breathy vowels described in the literature. Their “breathy” nature may have a historical source in initial glottal consonants that were lost, but is currently used as a phonetic strategy that is intended to enhance the perceptual contrast between syllables with a phonemic glottal onset versus onsetless syllables. We also suggest that the glottal stop in Kedang is phonemic in all positions and indicatea possible historical trajectory for its development.

Most psycholinguistic models of speech production agree on an earlier semantic processing stage and a later word-form encoding stage. Using a logographic language, Mandarin Chinese, Zhang and Weekes [2009. Orthographic facilitation effects on spoken word production: Evidence from Chinese. Language and Cognitive Processes, 24(7–8), 1082–1096. https://doi.org/10.1080/01690960802042133] reported an early effect of orthography in a picture-word-interference study and suggested orthography affects speech production via a lexical-semantic pathway at an early stage. This early orthographic effect without co-occurrence of phonological effect, however, was not replicated [Zhao, La Heij, & Schiller, 2012. Orthographic and phonological facilitation in speech production: New evidence from picture naming in Chinese. Acta Psychologica, 139(2), 272–280. https://doi.org/10.1016/j.actpsy.2011.12.001]. The present study aimed to dissociate further the semantic and phonological representations from orthography by using simplex Chinese characters. The results of Experiment 1 and 2 revealed an orthographic effect but only at a similar point in time as the phonological effect, both of which followed the semantic effect. Our results thus raise further doubts about the role of orthography at the conceptual level of speech planning and lend new evidence to a two-step model of speech production.