Impaired facilitation of self-control cognition by glucose in patients with schizophrenia: a randomized controlled study

Mental Fatigue in Sport-From Impaired Performance to Increased Injury Risk

The literature describing the effects of mental fatigue (MF) has grown tremendously. This is accompanied by identification of a host of performance-determining parameters affected by MF. MF results from prolonged cognitive effort and predominantly affects physical, technical, tactical, and perceptual-cognitive dimensions of sport, while physiological parameters (eg, heart rate, lactate) and physical aspects of maximal and supramaximal efforts are predominantly unaffected. The aim of this paper was to provide an overview of the parameters described in the literature as influenced by MF. By identifying the different parameters, we not only see how they affect the performance of athletes but also raise concerns about the potentially increased injury risk due to MF. Preliminary evidence suggests that subsequent disturbances in balance, motor skills, and decision-making processes could potentially increase the vulnerability to injury. An abundance of lab-based studies looked into the effects of MF on performance; however, many questions remain about the mechanisms of origin and neurophysiological causes of MF, and only small steps have been taken to translate this knowledge into practice. Thus, there is a need for more research into the underlying mechanisms of MF and the role of the brain, as well as more applied research with a high ecological validity that also takes into account the potential increased risk of injury due to MF.

Diabetes mellitus, cognitive deficits and serum BDNF levels in chronic patients with schizophrenia: A case-control study

The relationship between serum BDNF levels and cognitive dysfunction in schizophrenia (SCZ) patients comorbid with type 2 diabetes mellitus (T2DM) has not been reported. Hence, this study aimed to explore whether and how the changes of serum BDNF levels were correlated with cognitive impairment in SCZ patients comorbid with T2DM. We recruited 472 inpatients with chronic SCZ (54 T2DM and 418 non-T2DM), and 225 healthy controls. Serum BDNF levels and routine biochemical parameters were measured. Psychopathological symptoms were evaluated by the Positive and Negative Syndrome Scale (PANSS) and cognitive function was assessed by the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). SCZ patients with T2DM had significantly higher serum BDNF levels than SCZ patients without T2DM (F = 11.31, p = 0.001). SCZ patients with T2DM scored higher in delayed memory than SCZ patients without T2DM (77.17 ± 18.44 vs.66.24 ± 19.51, p = 0.000), and still showed significance after controlling for confounders. Further stepwise multiple regression analysis identified serum BDNF as an independent contributor to the RBANS attention of SCZ patients with T2DM (β = 0.30, t = 2.09, p = 0.042). The increase of BDNF levels and better cognitive performance, especially delayed memory, may be related to the pathophysiological process of T2DM in chronic SCZ patients.

Self-leadership and self-control strength in the work context

Purpose

Based on the limited strength model, the purpose of this paper is to examine the relationship of self-leadership strategies (behavior-focused strategies, constructive thought patterns) and qualitative and quantitative overload with subsequent self-control strength.

Design/methodology/approach

The present study is a field study with 142 university affiliates and two measurement occasions during a typical workday (before and after lunch). Self-control strength was measured using a handgrip task.

Findings

Hierarchical regression analyses revealed that self-leadership, quantitative overload, and qualitative overload were not directly associated with self-control strength at either of the two measurement occasions. Qualitative overload moderated the relationship between self-leadership and self-control strength, such that self-leadership was associated with lower self-control strength at both measurement occasions when individuals experienced high qualitative overload in the morning.

Practical implications

Employees and employers should be aware of the possibly depleting characteristics of self-leadership in order to be able to create a work environment allowing for the recovery and replenishment of self-control strength.

Originality/value

The present field study theoretically and methodologically contributes to the literature on self-leadership and self-control strength in the work context by investigating the depleting nature of self-leadership and workload.

Cognitive effects of a 30-min aerobic exercise bout on adults with overweight/obesity and type 2 diabetes

BACKGROUND

Several studies document reliable brain health benefits of acute exercise bouts. However, no prior studies have explored such effects among those living with co-morbid overweight/obesity and type 2 diabetes (T2DM), both of which are conditions associated with cognitive performance decrements.

PURPOSE

To examine the impact of a 30-min bout of moderate-intensity aerobic exercise on executive function among adults with overweight/obesity and T2DM, employing a widely used experimental paradigm.

METHODS

Thirty adults with overweight/obesity and T2DM were randomly assigned to moderate (30% maximal heart rate reserve) and minimal (r.p.m. 30-50; work load 5) intensity aerobic exercise. Pre-exercise to post-exercise changes in Stroop interference and Go/No-Go scores were compared across conditions.

RESULTS

Primary analyses revealed no overall effect of exercise condition on changes in Stroop or Go/No-Go performance. Post-hoc moderation analyses indicated that Stroop interference scores were reduced, following moderate exercise among female participants and among those who were more physically active.

CONCLUSION

The current study revealed no reliable benefit of acute aerobic exercise for overweight and obese individuals living with T2DM overall. There may be limited benefits for women and more and active subgroups, but the precise nature of such benefits remains unclear.

Empathy in schizophrenia: A meta-analysis of the Interpersonal Reactivity Index

Empathy is a complex construct, thought to contain multiple components. One popular measurement paradigm, the Interpersonal Reactivity Index (IRI), has been used extensively to measure empathic tendencies in schizophrenia research across four domains: empathic concern, perspective-taking, personal distress, and fantasy. However, no recent meta-analysis has been conducted for all four factors of this scale. The goal of this meta-analysis was to examine self-reported empathic tendencies for each factor of the IRI in people with schizophrenia as compared to healthy controls. A literature search revealed 32 eligible schizophrenia studies. The Hedges' g standardized difference effect size was calculated for each component using a random effects meta-analytic model. Compared to healthy controls, schizophrenia samples reported significantly reduced tendencies for empathic concern, perspective-taking, and fantasy, but significantly greater tendencies for personal distress. Duration of illness significantly moderated the results for perspective-taking such that those with a longer duration exhibited greater deficits; percent female significantly moderated the results for personal distress such that samples with more females exhibited reduced effect sizes. Future work is needed to examine the impact of heightened personal distress on the empathic tendencies and abilities of those with schizophrenia, including the possible role of emotion regulation.