Dual diagnosis in an Australian forensic psychiatric hospital: prevalence and implications for services

Despite a growing awareness of the unique needs of psychiatric patients with co-occurring substance abuse and dependence disorders (i.e. dual diagnosis), there is a dearth of research investigating the prevalence of dual diagnosis in forensic psychiatric populations. Similarly, little work has been done to determine the implications of dual diagnosis for forensic psychiatric patients. Patients at the Thomas Embling Hospital in Victoria, Australia, were assessed to determine the prevalence of substance abuse disorders and mental illnesses within this population. Results reveal that the majority of patients (approximately 74%) have a lifetime substance abuse or dependence disorder. Information was collected concerning patients' criminal histories and the Level of Service Inventory, Revised, was completed for each patient who participated. Results suggest that patients with both major mental illnesses and substance abuse disorders have more extensive criminal histories and demonstrate a higher level of risks and needs when compared with patients with major mental illness alone. The implications for the development and delivery of effective forensic mental health services that address both co-occurring disorders are also discussed.     

Repetition blindness: out of sight or out of mind?

Does repetition blindness represent a failure of perception or of memory? In Experiment 1, participants viewed rapid serial visual presentation (RSVP) sentences. When critical words (C1 and C2) were orthographically similar, C2 was frequently omitted from serial report; however, repetition priming for C2 on a postsentence lexical decision task was equivalent whether or not C1 was similar to C2. In Experiment 2, participants monitored RSVP sentences for a predetermined target. Participants frequently failed to detect the target when it was preceded by an orthographically similar word. In Experiment 3, the authors investigated the role of the attentional blink in this effect. These experiments suggest that repetition blindness is a failure of conscious perception, consistent with predictions of the token-individuation hypothesis.     

What is the right thing at the right time? Interactions between stages and processes of change among smokers who make a quit attempt.

C. A. Perz, C. C. DiClemente, and J. P. Carbonari (1996) claim support for the transtheoretical model notion that success in smoking cessation involves doing the right thing at the right time: emphasising experiential change processes during the contemplation and preparation stages and shifting to behavioral process activities during action. A key methodological limitation of Perz et al. was their failure to control for stage of change, a measure that has been shown to be predictive of cessation. This study replicates the prospective findings of Perz et al. in a different data set, then controls for stage of change when it is predictive of cessation, and finds that the measures of "appropriate" change process use developed by Perz et al. no longer predict cessation. The authors conclude that stage of change, in particular the distinction between smoking and not smoking, is more important than change process use in predicting cessation outcomes.     

Temporal integration of speech prosody is shaped by language experience: an fMRI study

Differences in hemispheric functions underlying speech perception may be related to the size of temporal integration windows over which prosodic features (e.g., pitch) span in the speech signal. Chinese tone and intonation, both signaled by variations in pitch contours, span over shorter (local) and longer (global) temporal domains, respectively. This cross-linguistic (Chinese and English) study uses functional magnetic resonance imaging to show that pitch contours associated with tones are processed in the left hemisphere by Chinese listeners only, whereas pitch contours associated with intonation are processed predominantly in the right hemisphere. These findings argue against the view that all aspects of speech prosody are lateralized to the right hemisphere, and promote the idea that varying-sized temporal integration windows reflect a neurobiological adaptation to meet the 'prosodic needs' of a particular language.     

Discrimination and the positive-negative asymmetry effect: ideological and normative processes

Research using the minimal group paradigm demonstrates that categorization and ingroup identification can foster intergroup discrimination. However, the positive-negative asymmetry effect shows that less discrimination occurs when negative rather than positive outcomes are distributed. The normative hypothesis explains this asymmetry by the stronger inappropriateness of discrimination in negative than in positive outcome distributions. Results obtained in this minimal group paradigm study (N = 257) did not replicate the asymmetry effect: discrimination occurred in both positive and negative outcome distributions, even if norms against discrimination were stronger in negative than in positive outcome distributions. The absence of the asymmetry effect is explained by the effect of the discrimination-justifying ideology.     

Hong Kong Chinese kindergartners learn to read English analytically

We examined the extent to which young Hong Kong Chinese children, taught to read English as a second language via a logographic "look and say" method, used information about letter names and letter sounds to learn English words. Forty children from each of three kindergarten grade levels (mean ages 3.8, 5.0, and 5.9 years old, respectively) were taught to pronounce novel English spellings that were based on letter-name (e.g., DK = Deke), letter-sound (DK = Dick), or visual (Dk= Jean) cues. By the 2nd year of kindergarten, children performed significantly better in the name condition than the other conditions. The 3rd-year kindergartners performed better in the sound condition than the visual condition as well. The results point to the importance of letter-name and letter-sound knowledge for learning to read English, regardless of native-language background or method of instruction.     

Computational models of the hippocampal region: linking incremental learning and episodic memory

The hippocampal region, a group of brain structures important for learning and memory, has been the focus of a large number of computational models. These tend to fall into two groups: (1) models of the role of the hippocampal region in incremental learning, which focus on the development of new representations that are sensitive to stimulus regularities and environmental context; (2) models that focus on the role of the hippocampal region in the rapid storage and retrieval of episodic memories. Rather than being in conflict, it is becoming apparent that both approaches are partially correct and might reflect the different functions of substructures of the hippocampal region. Future computational models will help to elaborate how these different substructures interact.