Memory problems are frequently associated with cannabis use, in both the short- and long-term. To date, reviews on the long-term cognitive sequelae of cannabis use have examined a broad range of cognitive functions, with none specifically focused on memory. Consequently, this review sought to examine the literature specific to memory function in cannabis users in the nontoxicated state with the aim of identifying the existence and nature of memory impairment in cannabis users and appraising potentially related mediators or moderators. Literature searches were conducted to extract well-controlled studies that investigated memory function in cannabis users outside of the acute intoxication period, with a focus on reviewing studies published within the past 10 years. Most recent studies have examined working memory and verbal episodic memory and cumulatively, the evidence suggests impaired encoding, storage, manipulation and retrieval mechanisms in long-term or heavy cannabis users. These impairments are not dissimilar to those associated with acute intoxication and have been related to the duration, frequency, dose and age of onset of cannabis use. We consider the impact of not only specific parameters of cannabis use in the manifestation of memory dysfunction, but also such factors as age, neurodevelopmental stage, IQ, gender, various vulnerabilities and other substance-use interactions, in the context of neural efficiency and compensatory mechanisms. The precise nature of memory deficits in cannabis users, their neural substrates and manifestation requires much further exploration through a variety of behavioural, functional brain imaging, prospective and genetic studies.

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Aim:  The present study assessed the relationship between maternal attitudes, beliefs and child feeding practices. It was hypothesised that: (i) maternal control over feeding would increase when mothers perceived their children as over‐ or underweight and were concerned about the weight status of their children; and (ii) mothers would express more concern about their daughters' weight, and report higher levels of control over feeding as a result. Methods:  Participants included 112 mothers and their children aged 2–6 years who were attending swim lessons at a Central Coast swim school. Mothers completed the Child Feeding Questionnaire to assess maternal attitudes, beliefs and control over child feeding. Child and maternal body mass indexes were measured. Correlational analyses, t‐tests and multiple regression analyses were performed. Results:  Mothers reported a high overall level of control in child feeding, and a low level of concern for child weight. Child overweight and obesity were marginally lower than reported in previous studies. Mothers reported more concern for their daughters' weight, but did not report increased control over feeding based on child gender. Pressure to eat was negatively associated with maternal education, suggesting a link between socioeconomic status and child feeding practices. Mothers displayed higher levels of parental control over obese than normal‐weight children, suggesting that they accurately assessed the weight status at the obese level. Conclusion:  Mothers may be able to detect obesity in their children, but not overweight. Mothers may also be unconcerned about their sons' weight, and this discrepancy should be investigated in clinical and educational settings. Nutrition education and child obesity prevention and treatment programs should take maternal attitudes, perceptions and child feeding practices into account when planning interventions.

Historically, brain tumour resection has relied upon standardised anatomical atlases and classical mapping techniques for successful resection. While these have provided adequate results in the past, the emergence of new technologies has heralded a wave of less invasive, patient-specific techniques for the mapping of brain function. Functional magnetic resonance imaging (fMRI) and, more recently, diffusion tensor imaging (DTI) are two such techniques. While fMRI is able to highlight localisation of function within the cortex, DTI represents the only technique able to elucidate white matter structures in vivo. Used in conjunction, both of these techniques provide important presurgical information for thorough preoperative planning, as well as intraoperatively via integration into frameless stereotactic neuronavigational systems. Together, these techniques show great promise for improved neurosurgical outcomes. While further research is required for more widespread clinical validity and acceptance, results from the literature provide a clear road map for future research and development to cement these techniques into the clinical setup of neurosurgical departments globally.

These findings indicate that chronic use of cannabis may impair the brain's ability to respond optimally in the presence of events that require conflict resolution and hold implications for the ability to refrain from substance misuse and/or maintain substance abstention behaviours.

Microstructural white matter changes have been reported in the brains of patients across a range of psychiatric disorders. Evidence now demonstrates significant overlap in these regions in patients with affective and psychotic disorders, thus raising the possibility that these conditions share common neurobiological processes. If affective and psychotic disorders share these disruptions, it is unclear whether they occur early in the course or develop gradually with persistence or recurrence of illness. Utilisation of a clinical staging model, as an adjunct to traditional diagnostic practice, is a viable mechanism for measuring illness progression. It is particularly relevant in young people presenting early in their illness course. It also provides a suitable framework for determining the timing of emergent brain alterations, including disruptions of white matter tracts. Using diffusion tensor imaging, we investigated the integrity of white matter tracts in 74 patients with sub-syndromal psychiatric symptoms as well as in 69 patients diagnosed with established psychosis or affective disorder and contrasted these findings with those of 39 healthy controls. A significant disruption in white matter integrity was found in the left anterior corona radiata and in particular the anterior thalamic radiation for both the patients groups when separately contrasted with healthy controls. Our results suggest that patients with sub-syndromal symptoms exhibit discernable early white matter changes when compared with healthy control subjects and more significant disruptions are associated with clinical evidence of illness progression.

The results indicate that relative to non-using controls, chronic users of cannabis have altered memory-related brain activation in the form of dysfunctional SME production and/or poorer neural efficiency, which is associated with deficits in memory recall. Greater alteration was associated with a longer history of cannabis use and an earlier onset of use. Neuroadaptation to the effects of chronic exposure may additionally play a role.

IntroductionA current topic of controversy in psychiatry is whether or not bipolar-spectrum disorders should be considered as part of the psychosis cluster in the upcoming DSM-V. Currently, bipolarspectrum disorders are classified as mood disorders in line with the Kraeplinian dichotomy; however, recent literature suggests that there may be more overlap in the underlying neurobiology in these major psychiatric illnesses than once thought.1 It is not unusual for patients with similar pheno typic presentation and common symptomatology to receive a diagnosis of either a bipolar-spectrum or a schizophrenia-spectrum disorder, particularly in the early stages of illness. Thus, investigation of the underlying neurobiology of these 2 major psychi atric groups is crucial to our understanding of their pathophysiological overlap. Shared genetic vulnerabilities in individuals with bipolar disorder and schizophrenia have been documented and describe how some symptoms overlap and how some are unique. [2][3][4][5] In support of the shared genetic basis of these disorders, there is evidence that first-degree relatives of probands with bipolar disorder or schizophrenia are at increased risk for either disorder, irrespective of the phenotype present in their relative. Background: Mismatch negativity (MMN) and P3a are event-related potentials that index deviance detection and the orienting response, respectively. We have previously shown that the MMN/P3a complex is impaired in patients with schizophrenia and affective spectrum psychoses, which suggests that it may index a common pathophysiology and argues against the purported specificity in schizo phrenia. Further research is warranted to determine whether patients with bipolar-spectrum disorders show similar impairments in these biomarkers. Methods: We assessed patients aged 15-30 years with early schizophrenia-spectrum disorders (schizophrenia, schizoaffective disorder, schizophreniform disorder), early bipolar-spectrum disorders (bipolar I or II, with and without psychotic features) and healthy, matched controls. We acquired MMN/P3a amplitudes during a 2-tone, auditory paradigm with 8% duration deviants. Clinical, psychosocial and neuro psychological assessments were also undertaken. Results: We included 20 patients with schizophrenia-spectrum disorders, 20 with bipolar-spectrum disorders and 20 controls in our study. Both patient groups showed significantly reduced frontocentral MMN and central P3a amplitudes. The schizophrenia-spectrum group had additional impairments in left temporal MMN and frontal P3a. Both patient groups performed worse than controls across psychosocial and clinical measures; however, only the schizophrenia-spectrum group performed significantly worse than controls for cognitive measures. Correlational analyses between patient groups revealed associations between frontocentral or left temporal MMN and psychiatric symptomatology or quality of life measures. Limitations: Limitations to our study include the modest sample size and the lack of control with r...