Background. The rate of binocular rivalry has been reported to be slower in subjects with bipolar disorder than in controls when tested with drifting, vertical and horizontal gratings of high spatial frequency.

No abstract

Despite clear public health benefits, implementation of a smoke-free policy may have untoward behavioural effects in institutional mental health settings. In addition, staff expectations and perceptions are critical. Salient factors appear to be preparation of staff and patients, appropriate training, avoidance of exceptions and inconsistency, considering alternatives to smoking to fill the gap created by the policy, and a culture of critical evaluation in practice. Such processes will facilitate understanding and cooperation so that mental health services are able to participate in important policy processes with implications for the health of patients and staff.

1. The synaptic linkage between single, identified slowly adapting type I (SAI) fibres and their central target neurones of the cuneate nucleus was examined in pentobarbitoneanaesthetized cats. Simultaneous extracellular recordings were made from individual cuneate neurones and from fine, intact fascicles of the lateral branch of the superficial radial nerve in which it was possible to identify and monitor the activity of each group II fibre. Individual SAI fibres were activated by static displacement and by vibration delivered with a fine probe (0-25-2 mm diameter) to their associated touch domes in the hairy skin of the forelimb. 2. Transmission properties across the synapse were analysed for nine SAI-cuneate pairs in which the single SAI fibre of each pair provided a suprathreshold input to the cuneate neurone. Neither spatial nor temporal summation was required for effective impulse transmission, and often more than 80 % of SAI impulses led to a response in the cuneate neurone. Responses of the cuneate neurones to single SAI impulses occurred at a short, fixed latency (S.D. often < 0 1 ms), and frequently consisted of a burst of two or three impulses, at low SAI input rates in particular. 3. The tight phase-locking in the responses to vibration of single SAI fibres was preserved in the cuneate responses for frequencies up to -400 Hz. However, as the impulse rates of the cuneate neurones were less than 150 impulses s', their impulse patterns could not

Background The treated prevalence of psychotic disorders in remote communities of Cape York and the Torres Strait, Australia, has been shown to be elevated compared with the Australian population. Our study used a unique dataset to assess treated incidence and prevalence of psychotic disorders and mortality over a 23-year period in the adult Indigenous population of this region. Methods Data was collated from a clinical database that contains complete psychiatric records from 1992 to 2015, extracted for all Indigenous patients who received treatment for a psychotic disorder from the Remote Area Mental Health Service, and linked to the Queensland Deaths Registry. We calculated 12-month treated prevalence and incidence for each calendar year. Mortality rates were compared to the overall and Indigenous population death rates in Queensland. Findings Between 1992 and 2015, 424 patients were treated for psychosis – an age-standardised 12-month prevalence of 1·7% in 2015, approximately two times higher in men than women, and three times higher in Aboriginal versus Torres Strait Islander populations. The highest treated prevalence was observed in 2015 in Aboriginal men (4.0%). A range of psychotic disorders were detected, including many substance-induced cases (n = 93) and schizophrenia (n = 252). The age-standardised 12-month incidence rate over the study period was 3.61 per 1000 person-years for women and 4.23 per 1000 person-years for men. Treated prevalence increased throughout the study period, largely attributable to increases in incidence of schizophrenia and schizoaffective disorder – in contrast, the incidence and prevalence of bipolar and mood disorders remained low and stable. Increased mortality risk compared to the Queensland Indigenous population (SMR = 1.9; 95% CI 1.4–2.6) was attributable to the elevated risk shown in the Aboriginal population in our study (SMR = 2.6; 95% CI 1.8–3.7). Interpretation Our results show extremely high prevalence rates of psychosis; increasing prevalence over time; differences in the distribution of psychosis between Aboriginal and Torres Strait Islander populations; and increased mortality risk for Aboriginal people living with psychosis in this region. These observations strongly suggest an aetiological role of environmental and neurodevelopmental factors, and the contribution of social factors to vulnerability and premature mortality. Role of the funding source This study was funded by who are the custodians of this database. The funder had no role in study design, data analysis, data interpretation, writing of the report, or submission for publication. All authors had full access to all the study data. The corresponding author had final responsibility for the decision to submit for publication. FJC is supported by an Australian National Health and Medical Research Council ( ) Early Career Fellowship (APP1138488). ...

Objective: To describe and characterise treated psychotic disorders in the Indigenous populations of Cape York and the Torres Strait. Design: Cross‐sectional analysis of patients with a psychotic disorder identified by treating psychiatrists. Setting and participants: Indigenous patients aged ≥ 15 years in Cape York and Torres Strait communities receiving treatment for a psychotic disorder over 3 months in 2010. Main outcome measures: Prevalence of psychosis diagnoses, intellectual disability, and substance use comorbidities. Results: 171 patients were included. The prevalence rate in this population was 1.68%, higher for males (2.60%) than females (0.89%), and twice as high in the Aboriginal (2.05%) than in the Torres Strait Islander (0.95%) population. High rates of alcohol and cannabis use were found. Comorbid intellectual disability was common and more frequent among Aboriginal patients. Conclusions: The burden of psychosis in the Indigenous population of Cape York and the Torres Strait is high. Further research is needed to understand the social determinants of these disorders and to design effective social and clinical measures to alleviate this burden.

Ketamine sedation is effective and safe in agitated patients with a psychiatric illness in the aeromedical setting and does not lead to worsening agitation in the subsequent 72-h period.

Transmission from single, identified, slowly adapting type II (SAII) tactile fibers to their target neurons in the cuneate nucleus was examined in anesthetized cats. Simultaneous recordings were made from cuneate neurons and from fine, intact fascicles of the superficial radial nerve in which it was possible to identify and monitor the activity of each group II fiber. Selective activation of individual SAII fibers was achieved by means of skin stimulation with fine probes, in conjunction with extensive forelimb denervation. Responses were studied for seven SAII-driven cuneate neurons. For three there was unequivocal monitoring of the identified SAII input fiber. However, in six of the seven there was evidence that just one SAII fiber provided suprathreshold input to the cuneate neuron, and neither temporal nor spatial summation was required for reliable transmission. Cuneate impulse rates, in response to SAII inputs lasting 1 s, were less than 250 impulses per second, even though the SAII impulse rates could be 500 s-1. Responses to individual SAII impulses consisted of a burst of 2-3 impulses at low SAII input rates, but burst responses disappeared at high SAII rates. In all three SAII-cuneate pairs studied, the transmission security (the percentage of SAII impulses that evoked cuneate spike output) exceeded 80% in response to static skin displacement and in response to certain frequencies of skin vibration, in particular, at 100-200 Hz, exceeded 98% when the SAII fiber responded near the 1:1 level (one impulse per vibration cycle).(ABSTRACT TRUNCATED AT 250 WORDS)