Roger Wales

Facial affect and affective prosody recognition in first-episode schizophrenia.

Individuals with schizophrenia experience problems in the perception of emotional material; however, the specificity, extent, and nature of the deficits are unclear. Facial affect and affective prosody recognition were examined in representative samples of individuals with first-episode psychosis, assessed as outpatients during the early recovery phase of illness, and non-patients. Perception tasks were selected to allow examination of emotion category results across face and voice modalities. Facial tasks were computerised modifications of the Feinberg et al. procedure (Feinberg, T.E., Rifkin, A., Schaffer, C., Walker, E., 1986. Arch. Gen. Psychiatry 43, 276--279). Prosody tasks were developed using four professional actors, and item selections were based on responses of undergraduates. Participant groups did not differ in their understanding of the words used to describe emotions. Findings supported small but consistent deficits in recognition of fear and sadness across both communication channels for the combined schizophrenia (n=29) and other psychotic disorders (n=28) groups as compared to the affective psychoses (n=23) and non-patients (n=24). A diagnostic effect was evident that was independent of the contribution of intelligence. The detection of emotion recognition impairments in first-episode schizophrenia suggests a trait deficit. The pattern of results is consistent with amygdala dysfunction in schizophrenia and related psychoses.

Constraints of Lexical Stress on Lexical Access in English: Evidence from Native and Non-native Listeners:

Four cross-modal priming experiments and two forced-choice identification experiments investigated the use of suprasegmental cues to stress in the recognition of spoken English words, by native (English-speaking) and nonnative (Dutch) listeners. Previous results had indicated that suprasegmental information was exploited in lexical access by Dutch but not by English listeners. For both listener groups, recognition of visually presented target words was faster, in comparison to a control condition, after stress-matching spoken primes, either monosyllabic ( mus-from MUsic/muSEum) or bisyllabic (admi-from ADmiral/admiRAtion ). For native listeners, the effect of stress-mismatching bisyllabic primes was not different from that of control primes, but mismatching monosyllabic primes produced partial facilitation. For non-native listeners, both bisyllabic and monosyllabic stress-mismatching primes produced partial facilitation. Native English listeners thus can exploit suprasegmental information in spoken-word recognition, but information from two syllables is used more effectively than information from one syllable. Dutch listeners are less proficient at using suprasegmental information in English than in their native language, but, as in their native language, use mono- and bisyllabic information to an equal extent. In forced-choice identification, Dutch listeners outperformed native listeners at correctly assigning a monosyllabic fragment (e.g., mus-) to one of two words differing in stress.

The development of speech production following cochlear implantation

Conversational speech samples were analysed over a six-year period postoperatively for nine profoundly deaf children implanted with the Cochlear Limited 22-electrode cochlear implant between ages 2-5 years. Four years post-implant, at least 90% of all syllables produced by each child were intelligible, although only one of the children (who had suffered a progressive hearing loss) had over 10% intelligible syllables prior to implantation. Over the 6-year period, the mean number of intelligible words per utterance increased from 0.15 to 4.2 and the mean number of syllables (counting both intelligible and unintelligible syllables) increased from 1.7 to 5.2, indicating an increase in complexity as well as intelligibility. The speech samples were transcribed phonetically and percentage correct analyses were conducted on the transcripts. These analyses showed a steady improvement in the percentage of correctly produced monophthongs, diphthongs and consonants. There was a corresponding rise in the percentage of words that were produced without phonetic errors. Following six years of implantation, the speech acquisition process was incomplete, although there was no evidence to suggest a plateau in performance.

An investigation of the ability to process inferences in language following right hemisphere brain damage

Twenty-two right hemisphere brain-damaged and 22 non-brain-damaged patients were given a multiple-choice recognition task which contained true statements, statements which were inferentially true but not actually heard before, and false statements. It was hypothesized that if right hemisphere brain damage disturbs the ability to comprehend inferences, these subjects, unlike their normal counterparts, would not falsely recognize true inferences as heard before. This hypothesis was not confirmed. However, the right hemisphere group was poorer than controls at rejecting false statements. This behavior was speculated to be a retrieval difficulty, which was exacerbated if the information contained spatial or semantically similar material.

Phrasal prosody disambiguates syntax

Two experiments tested whether phonological phrase boundary cues, as produced by naïve speakers, constrain syntactic analysis in French. Pairs of homophones belonging to different syntactic categories (verb and adjective) were inserted within locally ambiguous sentences that differed in their prosodic structure (e.g., [les pommes dures]…– hard apples… – versus [les pommes] [durent…] – apples last …– where brackets indicate phonological phrase boundaries). In Experiment 1 six speakers, unaware of the ambiguities, recorded the sentences. Acoustical analyses showed that they all produced reliable prosodic cues (phrase-final lengthening and pitch rise). Experiment 2 tested whether listeners exploited these prosodic cues to constrain syntactic analysis. They listened to the sentences beginnings (cut after the ambiguous word) and completed them in writing. Their assignments of the target words to their correct syntactic categories were better than chance. We discuss these results in light of the on-going debate about the production of disambiguating prosody by speakers who are unaware of the ambiguities.

Linguistic impairment in early psychosis.

Twenty-four, first-admission, psychotic subjects and 24 control subjects were administered a linguistic instrument to elicit impairments in syntax, semantics, cohesion, and use of metaphors. In the same session, the subjects were also rated on the Scale for Thought, Language, and Communication Disorders (TLC). Results indicated a significant impairment of all four linguistic categories in psychotic subjects. The impairment in semantics, however, was differentiated the most between the patient and control groups. The psychotic patients scored significantly higher on the TLC. Scores of impairment on the linguistic tasks did not correlate with scores on the TLC.

Phonological Phrase Boundaries Constrain the Online Syntactic Analysis of Spoken Sentences

Two experiments tested whether phonological phrase boundaries constrain online syntactic analysis in French. Pairs of homophones belonging to different syntactic categories (verb and adjective) were used to create sentences with a local syntactic ambiguity (e.g., [le petit chien mort], in English, the dead little dog, vs. [le petit chien] [mord], in English, the little dog bites, where brackets indicate phonological phrase boundaries). An expert speaker recorded the sentences with either a maximally informative prosody or a minimally informative one. Participants correctly assigned the appropriate syntactic category to the target word, even without any access to the lexical disambiguating information, in both a completion task (Experiment 1) and an abstract word detection task (Experiment 2). The size of the experimental effect was modulated by the prosodic manipulation (maximally vs. minimally informative), guaranteeing that prosody played a crucial role in disambiguation. The authors discuss the implications of these results for models of online speech perception and language acquisition.

Intonational Rises and Dialog Acts in the Australian English Map Task

Eight map task dialogs representative of General Australian English, were coded for speaker turn, and for dialog acts using a version of SWBDDAMSL, a dialog act annotation scheme. High, low, simple, and complex rising tunes, and any corresponding dialog act codes were then compared. Dialog acts corresponding to information requests were consistently realized as high-onset high rises((L+)H*H—H%).Howeverlow-onset high rises (e.g., L*H —H%) corresponded to a wider range of other “forward-looking” communicative functions, such as statements and action directives, and were rarely associated with information requests. Low-range rises (L*L—H%), by contrast, were mostly associated with backward-looking functions, like acknowledgments and responses, that is they were almost always used when the speaker was referring to what had occurred previously in the discourse. Two kinds of fall-rise tunes were also examined: the low-range fall-rise (H *L— H %) and the expanded range fall-rise (H * + L H —H %). The latter shared similar dialog functions with statement high rises, and were almost never associated with yes/no questions, whereas the low-range fall-rises were associated more with backward-looking functions, such as responses or acknowledgments. The Australian English statement high rise (usually realized as a L* H — H % tune) or “uptalk,” appears to be more closely related to the classic continuation rises, than to yes/no question rises of typologically-related varieties of English.

The uses of nouns and deixis in discourse production in Alzheimer's disease

Abstract Deixis is a linguistic tool derived from the Greek word for ‘pointing’ that handles reference in relation to the immediate communicative context. This study investigated the uses of deictic (spatial vs. person) and nouns, using multiple discourse tasks in 26 dementia of the Alzheimer type (DAT) patients and 26 demographically matched healthy elderly. The chief research findings were: (1) the effects of the DAT process differed across the spatial vs. person deictic forms and (2) the discourse task under study, hence the communicative context, determined the nature and degree of group differences as well as the relationship between discourse variables.

Asperger syndrome: how does it relate to non-verbal learning disability?

The syndrome of non-verbal learning disabilities (NLD) is associated with prominent non-verbal deficits such as reduced perceptual and spatial abilities, against a background of relatively intact verbal abilities. Asperger syndrome is one of the several developmental disorders for which Byron Rourke has claimed that almost all the signs and symptoms of NLD are present. This study investigated the claim utilizing a battery of neuropsychological tests that were found to be sensitive to NLD in the original learning disordered populations used to describe the syndrome. Children aged between 8 and 14 were recruited to form two groups: (1) children with Asperger syndrome (N=14) and (2) normal healthy schoolchildren (N=20). By contrast to the main principle outlined in the NLD model, children with Asperger syndrome did not display a relative difficulty with spatial- or problem-solving tasks; indeed, they displayed significantly higher performance on some non-verbal tasks in comparison with verbal tasks. It was only in relation to their high levels of psychosocial and interpersonal difficulties, which are also predicted on the basis of their psychiatric diagnosis, that the children with Asperger syndrome were clearly consistent with the NLD model in this study. These results raise questions about the relevance of the syndrome of NLD for children with Asperger syndrome.