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Background Research has established the independent relationships between depressive symptoms to cognition and functioning in depression; however, little is known about the role of mediators in this relationship. We explored the role of neurocognitive abilities, depressive symptom severity, dysfunctional attitudes, and functional capacity in predicting two dimensions of daily functioning in individuals with major depressive disorder (MDD). Methods One hundred and twenty-four participants (mean age = 46.26, SD = 12.27; 56% female) with a diagnosis of MDD were assessed on a standard neurocognitive battery, self-reported depressive symptoms, dysfunctional attitudes, and clinician-rated functional impairment. They completed a performance-based assessment of functional competence. Results Confirmatory path analyses were used to model the independent and mediated effects of variables on two domains of functioning: social (relationships and social engagement) and productive (household and community activities). Cognition and depressive symptoms both predicted productive functioning, and dysfunctional attitudes mediated each of these relationships. Functional competence was a significant mediator in the relationship between neurocognition and productive functioning. Depressive symptoms and cognition were direct predictors of social functioning with no significant mediators. Conclusions There are divergent pathways to different dimensions of daily functioning in MDD. Measurement implications include the consideration of multiple levels of predicting productive activities and more direct relationships with social outcomes. Treatments that directly target depressive symptoms and cognition might not generalize to improvements in everyday functioning if additional pathways to functioning are not addressed.

Objective Traditional neuropsychological assessment methods identify a subpopulation of individuals with Major Depressive Disorder (MDD) who demonstrate cognitive functioning below population norms. An even larger proportion of those with MDD self-report problems with cognition that interfere with daily roles and responsibilities. We aim to test whether an intraindividual deviation of cognitive functioning relative to premorbid estimates (idiographic impairment) may better characterize challenges for functional recovery in MDD. Method Adult participants with MDD (N = 111) who completed a baseline neuropsychological assessment battery for a cognitive remediation trial were used in analyses. We compared the frequency of cognitive impairment using the normative and idiographic approaches and examined how these indexes related to observed functioning, perceived functioning, and depression severity. Results While only 25% of the sample would be classified as cognitively impaired on a composite measure according to normative comparison standards, 62.2% of this group were classified as idiographically impaired using a conservative cut-off of at least 1 SD deviation below premorbid estimates. Idiographic cognitive impairment shared a stronger inverse relationship with perceived functional competence than normative cognitive impairment. Depressive symptoms did not significantly correlate with both normative and idiographic impairment. Conclusions In MDD, reliance on assessment of contemporary cognitive functioning might underestimate rates of those who could be considered cognitively impaired. Consideration of idiographic impairment may help explain gaps between normatively defined cognitive ability with subjective complaints and disability in MDD. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Major depressive disorder (MDD) is associated with persistent, impaired life functioning. Motivational deficits in physical and cognitive effort expenditure have not been evaluated as contributors to functional impairment in MDD. In this study, we adapted parallel measures of choices to expend physical and cognitive effort and assessed their associations with symptoms, cognition, and life functioning in 44 participants with MDD. Higher anhedonia severity predicted lower motivation for physical effort but not for cognitive effort. Lower cognitive effort motivation was associated with poorer life functioning even after controlling for previously established predictors of symptoms and cognitive impairment. Reduced cognitive effort motivation also had an indirect effect on the relationship between impaired cognitive and life functioning. Findings suggest motivational deficits in MDD present different barriers for recovery depending on the type of effort that is avoided. Physical effort motivation is associated with anhedonia severity, whereas cognitive effort motivation is relevant to life functioning.

Peri-urban lakes offer many valued ecosystem services, but their vulnerability to climate change and anthropogenic disturbances increases with increasing human populations the effects and interactions of multiple stressors on lakes can lead to unexpected outcomes, affecting societal and ecological values, it is necessary to evaluate ecosystem trajectories and respective drivers in peri-urban lakes. Better management practices could thus be applied to preserve ecosystem services of peri-urban lakes. We conducted a multi-proxy paleolimnological study on Cultus Lake, British Columbia, a Canadian peri-urban lake experiencing cultural eutrophication, to reconstruct a comprehensive ecological trajectory of the lake over the past ~ 200 years. We also integrated historical data as well as historical archival information to identify the potential drivers of the changes. We identified ca. 1800–1900 CE as a reference period, reflected in muted variations across most paleo-indicators. Minor increases in sedimentary δ15N ca. 1880–1940 CE coincided with the onset of anthropogenic modifications to the Cultus Lake watershed. Signs of early eutrophication were evident by ca. 1940 CE, as indicated by increases in all sedimentary pigments. By ca. 1970–1990 CE, elevated concentrations of sedimentary cyanobacterial pigments and changes in diatom species assemblages highlighted the potential interactive effects of multiple stressors, including cultural eutrophication, climate warming and declines in the endangered Cultus Lake sockeye salmon population. Recent (ca. 1990–2008 CE) declines in sedimentary pigments and increases in cladoceran fluxes suggested an increase in top-down control of the lake food web. From the collection of changes observed in the past ~ 200 years in our study, it is clear that Cultus Lake and its associated ecosystem services would benefit from abatement of nutrient loadings from terrestrial and atmospheric sources. Our study emphasizes the complexity and interactivity of drivers in peri-urban lake ecosystems and the necessity of long-term perspectives to contextualize modern ecological conditions to inform lake and watershed management.

Background Executive Functioning (EF) is an important factor for community functioning for people with severe mental illness. Cognitive remediation programs often improve EF, but do so by using multiple therapeutic techniques. Little is known regarding how individual treatment elements promote cognitive improvement. Oscillatory brain activity is a potential neurophysiological mechanism that may change as a result of targeted training on computerized exercises. The current study aimed to examine the effects of a brief EF training program on EEG and neurocognitive measures. Methods 25 people with severe mental illness were randomized to either 2 weeks of computerized EF training or control training. Training consisted of 1 h training sessions 3 times per week and 40 min of daily home training. Assessments examined EEG theta and alpha band oscillatory power during EF tasks and neurocognitive measures of EF. Results EF training resulted in greater frontal theta power and reduced posterior alpha power during computerized EF tasks than control training. Power in the alpha frequency band over frontal electrode sites did not significantly differ between the two groups as a result of training. Additionally, participants in the EF training experienced significantly greater improvement in EF ability as measured by neurocognitive tests than the control condition. Conclusions Two weeks of EF training is sufficient to produce neurophysiological and neurocognitive change. Frontal theta power and posterior alpha power may be important neurophysiological markers to consider in cognitive remediation studies, and the addition of a brief executive function training procedure to other psychosocial interventions is worth examining.

Depression is associated with impairment in cognition and everyday functioning. Mechanisms of cognitive dysfunction in depression and the factors that influence strategic deployment of cognitive abilities in complex environments remain elusive. In this study we investigated whether depression symptom severity is associated with disengagement from a working memory task (Paced Auditory Serial Addition Task; PASAT) with parametric adjustment of task difficulty.235 participants completed the Beck Depression Inventory, low and high cognitive load conditions of the PASAT, and quality of life. Cognitive disengagement was the sum of consecutive items in which participants did not proffer a response to the trial.Individuals with higher depression severity showed more cognitive disengagement on the high but not low cognitive load trial of the PASAT; they did not differ in number of correct responses. Increased disengagement from the low to high cognitive load was associated with more impaired quality of life.Depression severity is associated with increased disengagement from tasks as difficulty increases. These findings suggest the importance of measuring how cognitive skills are avoided in complex environments in addition to considering performance accuracy. Individuals with depressive symptoms might preferentially avoid cognitive tasks that are perceived as more complex in spite of intact ability.

Background: The medical culture is defined by mental illness stigma, non-disclosure, and avoidance of professional treatment. Little research has explored attitudes and help-seeking behaviors of psychiatry trainees if they were to become mentally ill. Method: Psychiatry residents ( n = 106) from training centres across Ontario, Canada completed a postal survey on their attitudes, barriers to disclosure, and help-seeking preferences in the context of hypothetically becoming mentally ill. Results: Thirty-three percent of respondents reported personal history of mental illness and the frequency of mental illness by year of training did not significantly differ. The most popular first contact for disclosure of mental illness was family and friends ( n = 61, 57.5%). Frequent barriers to disclosure included career implications ( n = 39 , 36.8%), stigma ( n = 11, 10.4%), and professional standing ( n = 15, 14.2%). Personal history of mental illness was the only factor associated with in-patient treatment choice, with those with history opting for more formal advice versus informal advice. Conclusions: At the level of residency training, psychiatrists are reporting barriers to disclosure and help-seeking if they were to experience mental illness. A majority of psychiatry residents would only disclose to informal supports. Those with a history of mental illness would prefer formal treatment services over informal services.

Major depression is associated with substantial cognitive impairment. Deficits in attention, memory, and executive functions affect most of those with depression and persist into remission for a substantial proportion. A growing body of research links prefrontal and hippocampal function to these cognitive impairments in depression. Further, overactivation of networks is common in depression, only to produce typical performance on cognitive tasks. Thus, we can view depression as a disorder of cognitive dysfunction related to both underactive and inefficient neural processing.

BACKGROUND: Schizophrenia is a debilitating disorder, with chronic impairments in multiple domains of life. Neurocognitive ability has been established as a reliable predictor of functional outcomes in schizophrenia, and thus is a frequent point of intervention. However, empirical evidence suggests that the path by which neurocognition is used to support functioning in real-world contexts is complex. While traditional cognitive remediation trials produce gains in neurocognition, few translate these gains to commensurate improvements in real-world functioning. Path analyses point to negative symptoms, social cognition, and competency in social and adaptive skills as additional factors that contribute to persistent functional disability in schizophrenia. To add to this complexity, it is possible the relevance of these barriers to functional recovery may vary depending on the diverse treatment goals of patients. We expand on this body of work by characterizing the indirect role of negative symptoms, social cognition, and skills competence in the relationship between neurocognition and individual domains of real-world functioning: work and residential. METHODS: Clinically stable schizophrenia outpatients (N=507) were assessed for neurocognitive ability (MATRICS), functional competence (UPSA), social cognition (MSCEIT), as well as clinical symptoms (SANS, BPRS). Separate confirmatory path analysis models, with work and residential functioning as independent outcome variables (MSIF), were examined with functional competence and social cognition as level one mediators of neurocognition. Anhedonia and avolition were entered as independent mediators of both level one mediators and as potential direct predictors of neurocognition. Final models were determined iteratively and by examination of fit statistics. RESULTS: The final models had excellent fit statistics and explained a significant amount of variance in work (R2 = .35) and residential (R2 = .25) functioning. Neurocognition had an effect on everyday residential functioning (r = -.27), though it was fully mediated by functional competence (r = .58). Social cognition mediated neurocognition in both models, but the path from social cognition to everyday outcomes was fully mediated by anhedonia for residential functioning (r = .34) and avolition for work functioning (r = .55). DISCUSSION: The novel results indicate a complex, indirect relationship between neurocognition and functioning, with distinct paths forming via the mediators of social cognition and negative symptoms depending on the type of functional impairment. Specifically, weaker neurocognition is linked with poor work functioning, and this was found to be due to deficits in social cognition and volition, or willingness to pursue activities. Neurocognition is inversely related to residential functioning via deficits in social cognition and hedonic capacity, which represents the degree one can derive pleasure or reward from activities. These distinct pathways to functioning underscore the need for interventions to be tailored to individual differences in functional impairment; patients with prominent vocational disability may require concurrent skills training to augment motivation to independently approach work roles and responsibilities, while those with requirements to improve daily living at home may require auxiliary reward sensitivity training.

Port Stephens, located in SE Australia, is a shallow estuary with an outer and inner basin separated by a narrow channel. Foraminiferal biofacies distribution reveals this complex physical environment. The flood-tide delta forms a transition between the wave-dominated open coast and the microtide-dominated estuary. Sand wave dynamics cause a shifting substrate, resulting in allochthonous assemblages of calcareous shelf species transported into the bay through a wide entrance. The muddy central basin is heavily bioturbated, and allows for an in-situ, mixed calcareous and agglutinated assemblage of a progressively more estuarine character. Burial of organic matter and increased bioturbation permits infaunal species to increase in abundance, but promotes calcium carbonate dissolution. The bayhead delta of the Karuah River is characterized by lithic-rich substrates that are associated with robust calcareous species. Tidal cycles, combined with low river-flux, provide nearly fully marine conditions far upstream into the Karuah River. Marginal regions, from sandy/muddy tidal flats to marsh, show distinct assemblages of opportunistic species that respond to tidal exposure, substrate variations, organic matter flux and salinities. Early diagenetic taphonomic loss, closely linked with bioturbation, needs to be considered in interpretations of microfossil assemblages. Foraminiferal biofacies analysis, in combination with the brackish-water ichnology model, is a powerful tool for recognizing Mesozoic marginal marine environments. Port Stephens, with its environmental complexity, offers a valuable modern analogue for estuarine deposits of the geological past.

Despite their rigorous training, studies have shown that physicians experience higher rates of mental illness, substance abuse, and suicide compared to the general population. An online questionnaire was sent to a random sample of physicians across Canada to assess physicians’ knowledge of the incidence of mental illness among physicians and their attitudes towards disclosure and treatment in a hypothetical situation where one developed a mental illness. We received 139 responses reflecting mostly primary care physicians and nonsurgical specialists. The majority of respondents underestimated the incidence of mental illness in physicians. The most important factors influencing respondent’s will to disclose their illness included career implications, professional integrity, and social stigma. Preference for selecting mental health treatment services, as either outpatients or inpatients, was mostly influenced by quality of care and confidentiality, with lower importance of convenience and social stigma. Results from this study suggest that the attitudes of physicians towards becoming mentally ill are complex and may be affected by the individual’s previous diagnosis of mental illness and the presence of a family member with a history of mental illness. Other factors include the individual’s medical specialty and level of experience. As mental illness is common among physicians, one must be conscious of these when offering treatment options.

Evidence supports a role for ceruloplasmin (ferroxidase I) in the release of iron to the blood from mammalian cells. However, recent studies with cultured cells have suggested that it has the opposite effect, and that iron deficiency enhances expression of ceruloplasmin. We therefore examined in rats how nutritional iron status would affect expression of ceruloplasmin. Groups of male Sprague-Dawley rats were reared on a low iron, starch-based diet for 6-8 wk; half were supplemented by injection of iron dextran. At killing, hematocrits of deficient rats were half normal. Supplemented rats had normal liver concentrations of ferritin and ferritin iron. No ferritin was detected in the livers of the deficient rats. Northern analysis showed that ferritin L and H mRNAs were present in the deficient livers, but expression was half that of the normal rats. There was also twice as much copper. Levels of circulating ceruloplasmin (measured by rocket immunoelectrophoresis) were not altered by iron deficiency, although p-phenylenediamine oxidase activity and plasma copper were reduced approximately 30%. In repeated studies, no differences in the expression of hepatic ceruloplasmin mRNA were detected. Treatment of rats of both sexes with additional iron (25 mg as iron dextran) 5-14 d before killing increased liver ferritin but did not alter liver ceruloplasmin mRNA expression or levels of circulating ceruloplasmin. We conclude that iron status is not an important factor in the expression of plasma ceruloplasmin made by the liver. However, it does have modest effects on steady-state levels of liver ferritin mRNA.