Rates of childhood trauma in a sample of patients with schizophrenia as compared with a sample of patients with non-psychotic psychiatric diagnoses

Despite strong evidence of high rates of childhood and adult trauma in schizophrenia, the area remains under-researched. Our objectives in the study were first, to examine the rates of exposure to childhood, adult and lifetime (child plus adult) trauma in a population with schizophrenia and a population with non-psychotic psychiatric diagnoses and second, to examine the effect of trauma on the symptoms of schizophrenia. Two groups, those with schizophrenia (n = 40), and those with a non-psychotic diagnosis (n = 30), were recruited. Data were collected for demographic, psychiatric and trauma histories for all participants and on psychosocial functioning and psychiatric symptomatology for the patients with schizophrenia. Childhood exposure to trauma was significantly more common in the schizophrenia group (t = 5.196, df = 68, p <0.001, Eta squared = 0.28), with the strongest relationship being childhood physical assault. In the schizophrenia group a history of trauma was significantly related to poor communication skills (r = -0.529, p <0.001) and depressive symptoms (r = 0.443, p = 0.004). Evidence that childhood exposure to trauma is more common in a population with schizophrenia is consistent with other studies and raises the possibility that such trauma is of etiological importance. Further research is required to replicate those findings, to elucidate possible pathways by which the experience of trauma may contribute to the development of schizophrenia, and to explore the relationship between a history of childhood trauma and the experience of depressive symptoms in schizophrenia.

High Speed FPGA-based implementations of Delayed-LMS filters

A variation of the least means squares (LMS) algorithm, called the delayed LMS (DLMS) algorithm is an ideally suited to achieve highly pipelined, adaptive digital filter implementations. The paper presents an efficient method of determining the delays in the DLMS filter and then transferring these delays using retiming in order to achieve fully pipelined circuit architectures for FPGA implementation. The method has been used to derive a series of retimed delayed LMS (RDLMS) architectures, which considerable reduce the number of delays and convergence time and give superior performance in terms of throughput rate when compared to previous work. Three circuit architectures and three hardware shared versions are presented which have been implemented using the Virtex-II FPGA technology resulting in a throughout rate of 182 Msample/s.