A Synthesis of Human-related Avian Mortality in Canada

Many human activities in Canada kill wild birds, yet the relative magnitude of mortality from different sources and the consequent effects on bird populations have not been systematically evaluated. We synthesize recent estimates of avian mortality in Canada from a range of industrial and other human activities, to provide context for the estimates from individual sources presented in this special feature. We assessed the geographic, seasonal, and taxonomic variation in the magnitude of national-scale mortality and in population-level effects on species or groups across Canada, by combining these estimates into a stochastic model of stage-specific mortality. The range of estimates of avian mortality from each source covers several orders of magnitude, and, numerically, landbirds were the most affected group. In total, we estimate that approximately 269 million birds and 2 million nests are destroyed annually in Canada, the equivalent of over 186 million breeding individuals. Combined, cat predation and collisions with windows, vehicles, and transmission lines caused > 95% of all mortality; the highest industrial causes of mortality were the electrical power and agriculture sectors. Other mortality sources such as fisheries bycatch can have important local or species-specific impacts, but are relatively small at a national scale. Mortality rates differed across species and families within major bird groups, highlighting that mortality is not simply proportional to abundance. We also found that mortality is not evenly spread across the country; the largest mortality sources are coincident with human population distribution, while industrial sources are concentrated in southern Ontario, Alberta, and southwestern British Columbia. Many species are therefore likely to be vulnerable to cumulative effects of multiple human-related impacts. This assessment also confirms the high uncertainty in estimating human-related avian mortality in terms of species involved, potential for population-level effects, and the cumulative effects of mortality across the landscape. Effort is still required to improve these estimates, and to guide conservation efforts to minimize direct mortality caused by human activities on Canada's wild bird populations. As avian mortality represents only a portion of the overall impact to avifauna, indirect effects such as habitat fragmentation and alteration, site avoidance, disturbance, and related issues must also be carefully considered

Early predictors of language and social communication impairments at ages 9-11 years: A follow-up study of early-referred children

Purpose: In this study, the authors aimed to evaluate hypotheses that early sociocognition will predict later social communication and early phonology will predict later morphosyntax in clinically referred preschoolers. Method: Participants were 108 children ages 9–11 years who had been referred to clinical services with concerns about language at age 2½–3½ years. Predictors at Time 1 (T1) were measures of sociocognition, word/nonword repetition, and receptive language. Outcome measures at Time 3 (T3) included a social communication questionnaire completed by parents and tests of nonword repetition, morphosyntax, and receptive language. Results: Group- and case-level analyses revealed early sociocognition to be the strongest predictor of social communication problems, which by T3 affected almost one third of the sample. At the group level, early phonology, which was a significant problem for the majority of children at T1, was a weak predictor of morphosyntax at T3. However, at the case level the majority of children with poor morphosyntax and nonword repetition at outcome had had very low repetition scores at T1. Conclusions: In early language referrals, it is important to identify and address sociocognitive problems, a considerable risk for later social communication and autism spectrum disorders. The majority of early-referred children had phonological problems, often severe, but these require further investigation to determine their longer term significance for language

Associated reading skills in children with a history of Specific Language Impairment (SLI)

A large cohort of 200 eleven-year-old children with Specific Language Impairment (SLI) were assessed on basic reading accuracy and on reading comprehension as well as language tasks. Reading skills were examined descriptively and in relation to early language and literacy factors. Using stepwise regression analyses in which age and nonverbal IQ were controlled for, it was found that a single word reading measure taken at 7 years was unsurprisingly a strong predictor of the two different types of reading ability. However, even with this measure included, a receptive syntax task (TROG) entered when reading accuracy score was the DV. Furthermore, a test of expressive syntax/narrative and a receptive syntax task completed at 7 years entered into the model for word reading accuracy. When early reading accuracy was excluded from the analyses, early phonological skills also entered as a predictor of both reading accuracy and comprehension at 11 years. The group of children with a history of SLI were then divided into those with no literacy difficulties at 11 and those with some persisting literacy impairment. Using stepwise logistic regression, and again controlling for IQ and age, 7 years receptive syntax score (but not tests of phonology, expressive vocabulary or expressive syntax/narrative) entered as a positive predictor of membership of the ‘no literacy problems’ group regardless of whether early reading accuracy was controlled for in step one. The findings are discussed in relation to the overlap of SLI and dyslexia and the long term sequelae of language impairment

Developmental pathways of language and social communication problems in 9-11 year olds: Unpicking the heterogeneity

This paper addressed relations between language, social communication and behaviour, and their trajectories, in a sample of 9-11-year-olds (n=91) who had been referred to clinical services with concerns about language as pre-schoolers. Children were first assessed at 2½-4 years, and again 18 months later. Results revealed increasing differentiation of profiles across time. By 9-11 years, 11% of the sample had social communication deficits, 27% language impairment, 20% both, and 42% neither. The size of group differences on key language and social communication measures was striking (2-3 standard deviations). Social communication deficits included autistic mannerisms and were associated with social, emotional and behavioural difficulties (SEBDs); in contrast, language impairment was associated with hyperactivity only. Children with both language and social communication problems had the most severe difficulties on all measures. These distinct school-age profiles emerged gradually. Investigation of developmental trajectories revealed that the three impaired groups did not differ significantly on language or SEBD measures when the children were first seen. Only low performance on the Early Sociocognitive Battery, a new measure of social responsiveness, joint attention and symbolic understanding, differentiated the children with and without social communication problems at 9-11 years. These findings suggest that some children who first present with language delay or difficulties have undetected Autism Spectrum Disorders which may or may not be accompanied by language impairment in the longer term. This new evidence of developmental trajectories starting in the preschool years throws further light on the nature of social communication and language problems in school-age children, relations between language impairment and SEBDs, and on the nature of early language development

Revisiting the exercise heart rate-music tempo preference relationship

In the present study, we investigated a hypothesized quartic relationship (meaning three inflection points) between exercise heart rate (HR) and preferred music tempo. Initial theoretical predictions suggested a positive linear relationship (Iwanaga, 1995a, 1995b); however, recent experimental work has shown that as exercise HR increases, step changes and plateaus that punctuate the profile of music tempo preference may occur (Karageorghis, Jones, & Stuart, 2008). Tempi bands consisted of slow (95–100 bpm), medium (115–120 bpm), fast (135–140 bpm), and very fast (155–160 bpm) music. Twenty-eight active undergraduate students cycled at exercise intensities representing 40, 50, 60, 70, 80, and 90% of their maximal HR reserve while their music preference was assessed using a 10-point scale. The Exercise Intensity x Music Tempo interaction was significant, F(6.16, 160.05) = 7.08, p < .001, ηp 2 =.21, as was the test for both cubic and quartic trajectories in the exercise HR–preferred-music-tempo relationship (p < .001). Whereas slow tempo music was not preferred at any exercise intensity, preference for fast tempo increased, relative to medium and very fast tempo music, as exercise intensity increased. The implications for the prescription of music in exercise and physical activity contexts are discussed

The preschool repetition test: An evaluation of performance in typically developing and clinically referred children

Purpose: To determine the psychometric properties of the Preschool Repetition Test (Roy & Chiat, 2004); to establish the range of performance in typically developing children and variables affecting this; and to compare the performance of clinically referred children. Method: The PSRep Test comprises 18 words and 18 phonologically matched nonwords systematically varied for length and prosodic structure. This test was administered to a ‘typical’ sample of children aged 2;0–4;0 (n=315) and a ‘clinic’ sample of children aged 2;6-4;0 (n=168), together with language assessments. Results: Performance in the typical sample was independent of gender and SES, but was affected by age, item length, and prosodic structure, and was moderately correlated with receptive vocabulary. Performance in the clinic sample was significantly poorer, but revealed similar effects of length and prosody, and similar relations to language measures overall, with some notable exceptions. Test-retest and interrater reliability were high. Conclusions: The PSRep Test is a viable and informative test. It differentiates within and between ‘typical’ and ‘clinic’ samples of children, and reveals some unusual profiles within the clinic sample. These findings lay the foundations for a follow-up study of the clinic sample to investigate the predictive value of the test

Genetic influences in different aspects of language development: The etiology of language skills in 4.5 year-old twins

The genetic and environmental etiologies of diverse aspects of language ability and disability, including articulation, phonology, grammar, vocabulary, and verbal memory, were investigated in a U.K. sample of 787 pairs of 4.5-year-old same-sex and opposite-sex twins. Moderate genetic influence was found for all aspects of language in the normal range. A similar pattern was found at the low end of the distribution with the exception of two receptive measures. Environmental influence was mainly due to nonshared factors, unique to the individual, with little influence from shared environment for most measures. Genetic and environmental influences on language ability and disability are quantitatively and qualitatively similar for males and females

Evidence from comprehensive independent validation studies for smooth pursuit dysfunction as a sensorimotor biomarker for psychosis

Smooth pursuit eye movements are considered a well-established and quantifiable biomarker of sensorimotor function in psychosis research. Identifying psychotic syndromes on an individual level based on neurobiological markers is limited by heterogeneity and requires comprehensive external validation to avoid overestimation of prediction models. Here, we studied quantifiable sensorimotor measures derived from smooth pursuit eye movements in a large sample of psychosis probands (N = 674) and healthy controls (N = 305) using multivariate pattern analysis. Balanced accuracies of 64% for the prediction of psychosis status are in line with recent results from other large heterogenous psychiatric samples. They are confirmed by external validation in independent large samples including probands with (1) psychosis (N = 727) versus healthy controls (N = 292), (2) psychotic (N = 49) and non-psychotic bipolar disorder (N = 36), and (3) non-psychotic affective disorders (N = 119) and psychosis (N = 51) yielding accuracies of 65%, 66% and 58%, respectively, albeit slightly different psychosis syndromes. Our findings make a significant contribution to the identification of biologically defined profiles of heterogeneous psychosis syndromes on an individual level underlining the impact of sensorimotor dysfunction in psychosis

Faster decline of pitch memory over time in congenital amusia

Congenital amusia (amusia, hereafter) is a developmental disorder that impacts negatively on the perception of music. Psychophysical testing suggests that individuals with amusia have above average thresholds for detection of pitch change and pitch direction discrimination; however, a low-level auditory perceptual problem cannot completely explain the disorder, since discrimination of melodies is also impaired when the constituent intervals are suprathreshold for perception. The aim of the present study was to test pitch memory as a function of (a) time and (b) tonal interference, in order to determine whether pitch traces are inherently weaker in amusic individuals. Memory for the pitch of single tones was compared using two versions of a paradigm developed by Deutsch (1970a). In both tasks, participants compared the pitch of a standard (S) versus a comparison (C) tone. In the time task, the S and C tones were presented, separated in time by 0, 1, 5, 10, and 15 s (blocked presentation). In the interference task, the S and C tones were presented with a fixed time interval (5 s) but with a variable number of irrelevant tones in between: 0, 2, 4, 6, and 8 tones (blocked presentation). In the time task, control performance remained high for all time in tervals, but amusics showed a performance decrement over time. In the interference task, controls and amusics showed a similar performance decrement with increasing number of irrelevant tones. Overall, the results suggest that the pitch representations of amusic individuals are less stable and more prone to decay than those of matched non-amusic individuals

Reduced Levels of Vasopressin and Reduced Behavioral Modulation of Oxytocin in Psychotic Disorders

Oxytocin (OT) and arginine vasopressin (AVP) exert robust influence on social affiliation and specific cognitive processes in healthy individuals. Abnormalities in these neuroendocrine systems have been observed in psychotic disorders, but their relation to impairments in behavioral domains that these endocrines modulate is not well understood. We compared abnormalities of OT and AVP serum concentrations in probands with schizophrenia (n = 57), schizoaffective disorder (n = 34), and psychotic bipolar disorder (n = 75); their first-degree relatives without a history of psychosis (n = 61, 43, 91, respectively); and healthy controls (n = 66) and examined their association with emotion processing and cognition. AVP levels were lower in schizophrenia (P = .002) and bipolar probands (P = .03) and in relatives of schizophrenia probands (P = .002) compared with controls. OT levels did not differ between groups. Familiality estimates were robust for OT (h 2 = 0.79, P = 3.97e−15) and AVP (h 2 = 0.78, P = 3.93e−11). Higher levels of OT were associated with better emotion recognition (β = 0.40, P < .001) and general neuropsychological function (β = 0.26, P = .04) in healthy controls as expected but not in any proband or relative group. In schizophrenia, higher OT levels were related to greater positive symptom severity. The dissociation of OT levels and behavioral function in all proband and relative groups suggests that risk and illness factors associated with psychotic disorders are not related to reduced OT levels but to a disruption in the ability of physiological levels of OT to modulate social cognition and neuropsychological function. Decreased AVP levels may be a marker of biological vulnerability in schizophrenia because alterations were seen in probands and relatives, and familiality was high