The acquisition of allophonic rules: statistical learning with linguistic constraints

Phonological rules relate surface phonetic word forms to abstract underlying forms that are stored in the lexicon. Infants must thus acquire these rules in order to infer the abstract representation of words. We implement a statistical learning algorithm for the acquisition of one type of rule, namely allophony, which introduces context-sensitive phonetic variants of phonemes. This algorithm is based on the observation that different realizations of a single phoneme typically do not appear in the same contexts (ideally, they have complementary distributions). In particular, it measures the discrepancies in context probabilities for each pair of phonetic segments. In Experiment 1, we test the algorithm's performances on a pseudo-language and show that it is robust to statistical noise due to sampling and coding errors, and to non-systematic rule application. In Experiment 2, we show that a natural corpus of semiphonetically transcribed child-directed speech in French presents a very large number of near-complementary distributions that do not correspond to existing allophonic rules. These spurious allophonic rules can be eliminated by a linguistically motivated filtering mechanism based on a phonetic representation of segments. We discuss the role of a priori linguistic knowledge in the statistical learning of phonology.     

Identifying lesions on structural brain images--validation of the method and application to neuropsychological patients

The study of neuropsychological disorders has been greatly facilitated by the localization of brain lesions on MRI scans. Current popular approaches for the assessment of MRI brain scans mostly depend on the successful segmentation of the brain into grey and white matter. These methods cannot be used effectively with large lesions because lesions usually impair segmentation. We propose a novel, fully automated approach for the delineation of brain lesions on MR scans. This method involves comparing a skull stripped, smoothed, unsegmented T1 images to a control group using the general linear model. We tested this method by using images with simulated lesions of different sizes and images containing real lesions from patients with language deficits. We also tested how varying the size of the Gaussian smoothing kernel affects detection. The simulation was informed by findings of a lesion morphological study also presented here. The proposed method detected simulated lesions effectively in the range of 30--90%相似文献   

CANTAB explicit memory is less impaired in addicted schizophrenia patients

It has been suggested that in order to sustain the lifestyle of substance abuse, addicted schizophrenia patients would have less negative symptoms, better social skills, and less cognitive impairments. Mounting evidence supports the first two assumptions, but data lack regarding cognition in dual diagnosis schizophrenia. Seventy-six schizophrenia outpatients (DSM-IV) were divided into two groups: with (n = 44) and without (n = 32) a substance use disorder. Motor speed and visuo-spatial explicit memory were investigated using CANTAB. As expected, dual diagnosis patients showed a better cognitive performance. Our results suggest either that substance abuse relieves the cognitive deficits of schizophrenia or that the patients with less cognitive deficits are more prone to substance abuse.     

Subliminal speech priming

We present a novel subliminal priming technique that operates in the auditory modality. Masking is achieved by hiding a spoken word within a stream of time-compressed speechlike sounds with similar spectral characteristics. Participants were unable to consciously identify the hidden words, yet reliable repetition priming was found. This effect was unaffected by a change in the speaker's voice and remained restricted to lexical processing. The results show that the speech modality, like the written modality, involves the automatic extraction of abstract word-form representations that do not include nonlinguistic details. In both cases, priming operates at the level of discrete and abstract lexical entries and is little influenced by overlap in form or semantics.     

What face inversion does to infants' counting abilities

Infants younger than 1 year do not correctly count the number of objects in a scene by using differences among their properties, unless these differences cross the broad category boundaries separating humans, animals, and artifacts. Here we show that face orientation influences whether 10- and 12-month-old infants count correctly or incorrectly. When infants saw two puppets appearing and disappearing behind an occluder successively and had no cues for numerosity other than differences among the puppets' properties, they correctly counted two puppets if one had an upright face and one an upside-down face. However, when the same puppets were both shown with faces upright, infants failed the task. Overall, this pattern of success and failure closely parallels the pattern of brain activations registered when adults and infants watch objects characterized by the same property contrasts.     

COVID-19 attitudes,cognitions, and behaviors in association with personal ideology and social media exposure: Findings from emerging adults in the Southern United States

In the U.S., the COVID-19 pandemic has been highly politicized and has been the subject of large-scale media misinformation. Personal ideologies—including religiosity and political leanings (i.e., conservative, liberal)—have heavily guided responses to the pandemic, particularly in the Southern United States. However, microenvironments like Southern U.S. universities provide a unique perspective into the juxtaposition of larger societal conservatism and the liberalism associated with higher education. In the current study, we examined Southern university students' political beliefs, religiosity, and social media exposure in association with their COVID-19 attitudes, cognitions, and behaviors. Participants' political beliefs were associated with their COVID-19 concern, myth acceptance, vaccination status, and likelihood to receive a future vaccination. Religiosity and social media exposure were more nuanced. Future research into personal ideologies as emerging adults develop their independent identities away from their parents, and how this process can impact health behaviors, is needed.     

Perception of musical tension in short chord sequences: The influence of harmonic function,sensory dissonance,horizontal motion,and musical training

This study investigates the effect of four variables (tonal hierarchies, sensory chordal consonance, horizontal motion, and musical training) on perceived musical tension. Participants were asked to evaluate the tension created by a chord X in sequences of three chords {C major → X → C major} in a C major context key. The X chords could be major or minor triads major-minor seventh, or minor seventh chords built on the 12 notes of the chromatic scale. The data were compared with Krumhansl’s (1990) harmonic hierarchy and with predictions of Lerdahl’s (1988) cognitive theory, Hutchinson and Knopoff’s (1978) and Parncutt’s (1989) sensory-psychoacoustical theories, and the model of horizontal motion defined in the paper. As a main outcome, it appears that judgments of tension arose from a convergence of several cognitive and psychoacoustics influences, whose relative importance varies, depending on musical training.