ABSTRACT
The prediction and subsequent management of aggression by psychiatric inpatients is a crucial role of the mental health professional. This retrospective cohort study examines the predictive validity of 10 static and dynamic risk-of-violence measures and subscales in 37 forensic and 37 civil inpatients residing in a medium- to-low security psychiatric facility for a period of up to 6 months. Retrospective file records were sourced to conduct an AUC analysis of the ROC curve for short- and medium-term follow-up periods. The hypothesis that dynamic measures would be better predictors than static measures over the short term was supported. Albeit to a lesser extent, dynamic measures were still better predictors than static measures over the medium term. This result was seen in both civil and forensic groups. Three previously untested measures were found to predict aggression within the sample. It is recommended that mental health services employ the use of dynamic measures when making short-term risk-of-violence predictions for civil and/or forensic inpatients.
ABSTRACT
Temporal and spectral sound information is processed asymmetrically in the brain with the left-hemisphere showing an advantage for processing the former and the right-hemisphere for the latter. Using monaural sound presentation we demonstrate a context and ability dependent ear-asymmetry in brain measures of temporal change detection. Our measure of temporal processing ability was a gap-detection task quantifying the smallest silent gap in a sound that participants could reliably detect. Our brain measure was the size of the mismatch-negativity (MMN) auditory event-related potential elicited to infrequently presented gap sounds. The MMN indexes discrimination ability and is automatically generated when the brain detects a change in a repeating pattern of sound. MMN was elicited in unattended sequences of infrequent gap-sounds presented among regular no-gap sounds. In Study 1, participants with low gap-detection thresholds (good ability) produced a significantly larger MMN to gap sounds when sequences were presented monaurally to the right-ear than to the left-ear. In Study 2, we not only replicated a right-ear-advantage for MMN in silence in good temporal processors, but also showed that this is reversed to a significant left-ear-advantage for MMN when the same sounds are presented against a background of constant low-level noise. In both studies, poor discriminators showed no ear-advantage, and in Study 2, exhibited no differential sensitivity of the ears to noise. We conclude that these data reveal a context and ability-dependent asymmetry in processing temporal information in non-speech sounds.
