ABSTRACT
BACKGROUND: People with severe mental illness (SMI) have high rates of chronic disease and premature death. AIMS: To explore the strength of evidence for interventions to reduce risk of mortality in people with SMI. METHOD: In a meta-review of 16 systematic reviews of controlled studies, mortality was the primary outcome (8 reviews). Physiological health measures (body mass index, weight, glucose levels, lipid profiles and blood pressure) were secondary outcomes (14 reviews). RESULTS: Antipsychotic and antidepressant medications had some protective effect on mortality, subject to treatment adherence. Integrative community care programmes may reduce physical morbidity and excess deaths, but the effective ingredients are unknown. Interventions to improve unhealthy lifestyles and risky behaviours can improve risk factor profiles, but longer follow-up is needed. Preventive interventions and improved medical care for comorbid chronic disease may reduce excess mortality, but data are lacking. CONCLUSIONS: Improved adherence to pharmacological and physical health management guidelines is indicated.
Subject(s)
Chronic Disease/mortality , Chronic Disease/therapy , Mental Disorders/complications , Mental Disorders/mortality , Outcome and Process Assessment, Health Care , Chronic Disease/drug therapy , HumansABSTRACT
The Mismatch Negativity (MMN) response has often been used to measure memory traces for phonological representations and to show effects of long-term native language (L1) experience on neural organization. We know little about whether phonological representations of non-native (L2) phonemes are modulated by experience with distinct non-native accents. We used MMN to examine effects of experience with L2-accented speech on auditory brain responses. Specifically, we tested whether it is long-term experience with language-specific L2 pronunciations or instead acoustic similarity between L2 speech sounds that modulates non-native phoneme perception. We registered MMN responses of Dutch and German proficient L2 speakers of English to the English interdental fricative /ð/ and compared it to its non-native pronunciations /s/ (typical pronunciation of /ð/ for German speakers) and /t/ (typical pronunciation of /ð/ for Dutch speakers). Dutch and German listeners heard the English pseudoword thond and its pronunciation deviants sond and tond. We computed the identity Mismatch Negativity (iMMN) by analyzing the difference in ERPs when the deviants were the frequent vs. the infrequent stimulus for the respective group of L2 listeners. For both groups, tond and sond elicited mismatch effects of comparable size. Overall, the results suggest that experience with deviant pronunciations of L2 speech sounds in foreign-accented speech does not alter auditory memory traces. Instead, non-native phoneme perception seems to be modulated by acoustic similarity between speech sounds rather than by experience with typical L2 pronunciation patterns.
ABSTRACT
We investigated the role of the syllable during speech processing in German, in an auditory-auditory fragment priming study with lexical decision and simultaneous EEG registration. Spoken fragment primes either shared segments (related) with the spoken targets or not (unrelated), and this segmental overlap either corresponded to the first syllable of the target (e.g., /teis/ - /teisti/), or not (e.g., /teis/ - /teistlÉs/). Similar prime conditions applied for word and pseudoword targets. Lexical decision latencies revealed facilitation due to related fragments that corresponded to the first syllable of the target (/teis/ - /teisti/). Despite segmental overlap, there were no positive effects for related fragments that mismatched the first syllable. No facilitation was observed for pseudowords. The EEG analyses showed a consistent effect of relatedness, independent of syllabic match, from 200 to 500 ms, including the P350 and N400 windows. Moreover, this held for words and pseudowords that differed however in the N400 window. The only specific effect of syllabic match for related prime-target pairs was observed in the time window from 200 to 300 ms. We discuss the nature and potential origin of these effects, and their relevance for speech processing and lexical access.
ABSTRACT
With neurophysiological (N100) and explicit behavioral measures (two-alternative forced-choice categorization), we investigated how the processing of nasal segments of German is affected by following context phonemes and their place of articulation. We investigated pre-lexical processing, with speech stimuli excised from naturally spoken utterances. Participants heard nasals (/n/, /m/, and place-assimilated /n'/), both with and without a subsequent context phoneme. Context phonemes were voiced or voiceless, and either shared or did not share their place of articulation with the nasals. The explicit forced-choice categorization of the isolated nasals showed /n'/ to be in-between the clear categorizations for /n/ and /m/. In early, implicit processing, /m/ had a significantly higher N100 amplitude than both /n/ and /n'/, with, most importantly, no difference between the latter two. When presented in context (e.g., /nb/, /mt/), explicit categorizations were affected by both the nasal and the context phoneme: a consecutive labial led to more M-categorizations, a following alveolar to more N-categorizations. The early processing of the nasal/+context stimuli in the N100 showed strong effects of context, modulated by the type of preceding nasal. Crucially, the context effects on assimilated nasals /n'/ were clearly different to effects on /m/, and indistinguishable from effects on /n/. The grouping of the isolated nasals in the N100 replicates previous findings, using magnetoencephalography and a different set of stimuli. Importantly, the same grouping was observed in the nasal/+context stimuli. Most models that deal with assimilation are either challenged by the mere existence of phonemic context effects, and/or use mechanisms that rely on lexical information. Our results support the existence, and early activation, of pre-lexical categories for phonemic segments. We suggest that due to experience with assimilation, specific speech-sound categories are flexible enough to accept (or even ignore) inappropriate place cues, in particular when the appropriate place information is still present in the signal.
ABSTRACT
Several software programs exist to assist researchers in setting up online questionnaires. Existing tools are of little help for delivering online rating studies, for which it is often desirable to collect data from participants for only a subset of a stimulus set. OR-Vis enables researchers to quickly set up online rating studies by supplying the set of items to be rated, the number of stimuli an individual participant responds to, the number of participants an item is shown to, and the rating questions. The software then generates and delivers unique questionnaires for each participant, while managing the data collection process. The present article describes OR-Vis, its installation process, and how to use it to gather data. OR-Vis is open-source software and can be downloaded from www.orvis.uni-muenster.de.
Subject(s)
Electronic Data Processing/methods , Internet , Software , Surveys and Questionnaires , HumansABSTRACT
During speech perception, sound is mapped onto abstract phonological categories. Assimilation of place or manner of articulation in connected speech challenges this categorization. Does assimilation result in categorizations that need to be corrected later on, or does the system get it right immediately? Participants were presented with isolated nasals (/m/ labial, /n/ alveolar, and /n'/ assimilated towards labial place of articulation), extracted from naturally produced German utterances. Behavioural two-alternative forced-choice tasks showed that participants could correctly categorize the /n/s and /m/s. The assimilated nasals were predominantly categorized as /m/, indicative of a perceived change in place. A pitch variation additively influenced the categorizations. Using magnetoencephalography (MEG), we analysed the N100m elicited by the same stimuli without a categorization task. In sharp contrast to the behavioural data, this early, automatic brain response ignored the assimilation in the surface form and reflected the underlying category. As shown by distributed source modelling, phonemic differences were processed exclusively left-laterally (temporally and parietally), whereas the pitch variation was processed in temporal regions bilaterally. In conclusion, explicit categorization draws attention to the surface form - to the changed place and acoustic information. The N100m reflects automatic categorization, which exploits any hint of an underlying feature.
Subject(s)
Acoustic Stimulation/classification , Auditory Perception/physiology , Choice Behavior/physiology , Phonetics , Acoustic Stimulation/methods , Adult , Female , Humans , Male , Young AdultABSTRACT
Four experiments investigated the role of frequency information in compound production by independently varying the frequencies of the first and second constituent as well as the frequency of the compound itself. Pairs of Dutch noun-noun compounds were selected such that there was a maximal contrast for one frequency while matching the other two frequencies. In a position-response association task, participants first learned to associate a compound with a visually marked position on a computer screen. In the test phase, participants had to produce the associated compound in response to the appearance of the position mark, and we measured speech onset latencies. The compound production latencies varied significantly according to factorial contrasts in the frequencies of both constituting morphemes but not according to a factorial contrast in compound frequency, providing further evidence for decompositional models of speech production. In a stepwise regression analysis of the joint data of Experiments 1-4, however, compound frequency was a significant nonlinear predictor, with facilitation in the low-frequency range and a trend toward inhibition in the high-frequency range. Furthermore, a combination of structural measures of constituent frequencies and entropies explained significantly more variance than a strict decompositional model, including cumulative root frequency as the only measure of constituent frequency, suggesting a role for paradigmatic relations in the mental lexicon.