Improvement In Cognitive Flexibility Research Articles

Xanthohumol improved cognitive flexibility in young mice

The protein palmitoylation cycle has been shown to be important for protein signaling and synaptic plasticity. Data from our lab showed a change in the palmitoylation status of certain proteins with age. A greater percentage of the NMDA receptor subunits GluN2A and GluN2B, along with Fyn and PSD95 proteins, were palmitoylated in the old mice. The higher level of protein palmitoylation was also associated with poorer learning scores. Xanthohumol is a prenylated flavonoid that has been shown to increase beta-oxidation in the livers of rodents, decreasing circulating free fatty acids in the serum. What is not known is whether the application of xanthohumol could influence the palmitoylation status of proteins. In this study, young and old mice were fed a diet supplemented with xanthohumol for 8 weeks. Spatial memory was assessed with the Morris water maze and protein palmitoylation quantified. The young xanthohumol-treated mice showed a significant improvement in cognitive flexibility. However, this appeared to be associated with the young control mice, on a defined, phytoestrogen-deficient diet, performing as poorly as the old mice and xanthohumol reversing this effect. The old mice receiving xanthohumol did not significantly improve their learning scores. Xanthohumol treatment was unable to affect the palmitoylation of NMDA receptor subunits and associated proteins assessed in this study. This evidence suggests that xanthohumol may play a role in improving cognitive flexability in young animals, but it appears to be ineffective in adjusting the palmitoylation status of neuronal proteins in aged individuals.

Investigating cognitive flexibility as a potential mechanism of mindfulness in Generalized Anxiety Disorder

Background and objectivesResearch suggests mindfulness-based treatments may enhance efficacy of CBT for Generalized Anxiety Disorder (GAD). One hypothesized mechanism of mindfulness is cognitive flexibility; however, research findings to date are mixed as to a) whether cognitive inflexibility represents a characteristic of GAD, and b) whether mindfulness impacts cognitive flexibility. It is proposed that limitations in study methodology may partially account for these mixed findings. The present study investigated cognitive flexibility as a potential mechanism of mindfulness in a sample with elevated GAD symptoms using a modified emotional Stroop switching task while attempting to control for limitations of previous research. The purpose of the study was: 1) to explore cognitive inflexibility as a potential characteristic of GAD, and 2) to examine whether a brief mindfulness induction has measurable impact on cognitive flexibility. MethodsA total of 66 participants (53 with elevated GAD symptoms, and 13 non-anxious) were randomized to a mindful-breathing, music-assisted relaxation, or thought wandering condition prior to completing an emotional Stroop and emotional Stroop switching task. ResultsResults suggest that GAD may be characterized by an inflexible style of responding, and exposure to mindfulness and relaxation result in partial improvements in cognitive flexibility. LimitationsLimitations of this study include small sample size, brief induction period, and use of an analog sample. ConclusionsThe present findings suggest that mindfulness may be associated with partial improvement in cognitive flexibility.

The Use of Guided Self‐help Incorporating a Mobile Component in People with Eating Disorders: A Pilot Study

The aim of this pilot study was to test the acceptability and benefit of a guided self-help intervention incorporating a mobile component in eating disorders (EDs). Eighteen people with Anorexia Nervosa and eleven people with Bulimia Nervosa were included in the study for 3 weeks and self-report and behavioural assessments were made before and after the intervention which included 10 video clips, a manual, and limited guidance. The most reported positive comment associated with the use of the vodcasts was the increased awareness about the illness. Adherence was good (29/31 subjects completed). A medium sized increase in Body Mass Index was found in participants with Anorexia Nervosa, and significantly lowered EDs and mood symptoms (effect size range = 0.72/1.35), and improvement in cognitive flexibility were reported post-intervention. A guided self-help intervention incorporating a mobile component was both acceptable and associated with symptom change in people with EDs.

Cognitive Training for Improving Executive Function in Chemotherapy-Treated Breast Cancer Survivors

BackgroundA majority of breast cancer (BC) survivors, particularly those treated with chemotherapy, experience long-term cognitive deficits that significantly reduce quality of life. Among the cognitive domains most commonly affected include executive functions (EF), such as working memory, cognitive flexibility, multitasking, planning, and attention. Previous studies in other populations have shown that cognitive training, a behavioral method for treating cognitive deficits, can result in significant improvements in a number of cognitive skills, including EF. Materials and MethodsIn this study, we conducted a randomized controlled trial to investigate the feasibility and preliminary effectiveness of a novel, online EF training program in long-term BC survivors. A total of 41 BC survivors (21 active, 20 wait list) completed the 48 session training program over 12 weeks. The participants were, on average, 6 years after therapy. ResultsCognitive training led to significant improvements in cognitive flexibility, verbal fluency and processing speed, with marginally significant downstream improvements in verbal memory as assessed via standardized measures. Self-ratings of EF skills, including planning, organizing, and task monitoring, also were improved in the active group compared with the wait list group. ConclusionsOur findings suggest that EF skills may be improved even in long-term survivors by using a computerized, home-based intervention program. These improvements may potentially include subjective EF skills, which suggest a transfer of the training program to real-world behaviors.

The Acute Effects of a Single Bout of Moderate-intensity Aerobic Exercise on Cognitive Functions in Healthy Adult Males

Single acute bouts of moderately-intense aerobic exercise like walking have been found to improve cognitive control of attention in children, but some studies have reported no improvement in cognitive flexibility following acute aerobic exercise. Submaximal aerobic exercise performed for 60 minutes facilitated specific aspects of information processing in adults but extended exercises leading to dehydration compromised both information processing and memory functions. Improvement in executive functions has also been reported during cycling at 70% of Heart Rate Reserve (HRR) across young and older age groups. However, there are studies which have reported no correlation between physical activity and academic performance in children and a recent systematic review of 30 relevant studies reported no significant improvement in cognition with physical activity or exercise in adults. There seems to be lack of consensus on the effect of exercise on cognition, which may be because the exercise protocols used and cognitive functions tested by different researchers were not uniform. The primary aim of this study was to investigate the acute effects of aerobic exercise across different cognitive domains in healthy young individuals. A homogeneous group of 10 right handed healthy adult males participated in the study and was subjected to 8 cognitive function tests including 2 tests each across the four categories: Memory, Reasoning, Concentration and Planning using a pre-validated web based tool. Following baseline testing, subjects performed 30 minutes' of cycling on a stationary bicycle ergometer at moderate intensity (60-70% of HRR). Post-test scores were recorded when heart rate returned to within 10% of baseline. Pre and post-test scores were compared using the paired t-test. After exercise, there was significant improvement (Mean ± SD) in the Paired Associates (4.8±1.0 Vs 5.5 ± 1.0), Odd One Out (10.5 ± 3.0 Vs 13 ± 3.1) and Spatial Slider test (30.4 ± 17.8 Vs 40.5 ± 13.9), the tests of Memory, Reasoning and Planning respectively. No significant improvement was found for concentration. Total post-test time was significantly lower than the pre-test time (23.5 ± 2.55 Vs 21.2 ± 1.48 minutes). A single bout of moderate intensity aerobic exercise for as less as 30 minutes can improve some aspects of cognition, most prominently for memory, reasoning and planning and can shorten the time taken to complete the tests.

Is EEG-biofeedback an Effective Treatment in Autism Spectrum Disorders? A Randomized Controlled Trial

EEG-biofeedback has been reported to reduce symptoms of autism spectrum disorders (ASD) in several studies. However, these studies did not control for nonspecific effects of EEG-biofeedback and did not distinguish between participants who succeeded in influencing their own EEG activity and participants who did not. To overcome these methodological shortcomings, this study evaluated the effects of EEG-biofeedback in ASD in a randomized pretest-posttest control group design with blinded active comparator and six months follow-up. Thirty-eight participants were randomly allocated to the EEG-biofeedback, skin conductance (SC)-biofeedback or waiting list group. EEG- and SC-biofeedback sessions were similar and participants were blinded to the type of feedback they received. Assessments pre-treatment, post-treatment, and after 6 months included parent ratings of symptoms of ASD, executive function tasks, and 19-channel EEG recordings. Fifty-four percent of the participants significantly reduced delta and/or theta power during EEG-biofeedback sessions and were identified as EEG-regulators. In these EEG-regulators, no statistically significant reductions of symptoms of ASD were observed, but they showed significant improvement in cognitive flexibility as compared to participants who managed to regulate SC. EEG-biofeedback seems to be an applicable tool to regulate EEG activity and has specific effects on cognitive flexibility, but it did not result in significant reductions in symptoms of ASD. An important finding was that no nonspecific effects of EEG-biofeedback were demonstrated.

Fitness’s Moderation of the Facilitative Effect of Acute Exercise on Cognitive Flexibility in Older Women

A recent study indicated that acute aerobic exercise improves cognitive flexibility in adults. The current study assessed age, habitual physical activity, and physical fitness as moderators of this improvement and examined whether the gains still exist an hour after the exercise session. The alternative-uses test, assessing cognitive flexibility, was administered individually to 20 older (age 63.67 +/- 3.55 yr) and 19 young (age 23.9 +/- 1.22) women before, immediately after, and an hour after a single moderate aerobic-exercise session. Results indicated significant improvement in cognitive flexibility in the older group immediately after the exercise but a decrease at the 1-hr follow-up. Further analysis indicated that physical fitness accounted for this improvement (R = -.622, p < .01). No such differences were observed in the young group. Further studies are needed to examine the duration of this effect, as well as the role of physical fitness as a moderator of it.

Cognitive remediation therapy (CRT) for young early onset patients with schizophrenia: An exploratory randomized controlled trial

BackgroundSchizophrenia with an onset in adolescence is known to be associated with a poorer outcome and cognitive difficulties. These impairments have an impact on quality of life and represent treatment targets. Cognitive remediation therapy (CRT) attempts to improve cognitive deficits by teaching information processing strategies through guided mental exercises. The objective of this study is to evaluate the efficacy of CRT in alleviating cognitive deficits compared to treatment as usual and explore the mediating and moderating effects of cognitive improvement. MethodSingle-blind randomized controlled trial with two groups, one receiving CRT (N21) and the other standard care (N19) assessed at baseline, 3 months (post therapy) and follow-up (3 months post therapy). Participants were recruited from specialist inpatient and community mental health services and were young patients with recent onset schizophrenia (average age of 18) and evidence of cognitive and social behavioural difficulties. The intervention was individual cognitive remediation therapy delivered over a period of 3 months with at least three sessions per week. The main outcome measures were cognition (memory, cognitive flexibility and planning) and secondary outcomes (symptoms, social contacts and self-esteem). ResultsCompared to standard care, CRT produced significant additional improvements in cognitive flexibility as measured by the Wisconsin Card Sort Test (WCST). Therapy moderated the effects of improved planning ability on symptoms such that improvements only had a beneficial effect when they were achieved in the context of CRT. Improvements in cognition in all domains had a direct effect on social functioning and improvements in WCST had a direct effect on overall symptom improvement. ConclusionsCognitive remediation therapy can contribute to the improvement in WCST even in adolescents. The changes in cognitive outcomes also contributed to improvements in functioning either directly or solely in the context of CRT. Evidence of the mediator and moderator effects of cognitive changes should lead to more effective therapy development.

Cognitive remediation therapy in schizophrenia

Cognitive difficulties are prevalent in people with a diagnosis of schizophrenia and are associated with poor long-term functioning. To evaluate the effectiveness of cognitive remediation therapy on cognitive difficulties experienced by people with schizophrenia. Participants with a diagnosis of schizophrenia, a social behaviour problem and a cognitive difficulty (n=85) were randomised to 40 sessions of cognitive remediation or treatment as usual in a single-blind randomised controlled trial. Working memory, cognitive flexibility and planning, were measured at weeks 0,14 and 40. There were durable improvements in working memory (advantage 1.33 points, 95% CI 0.43-2.16, standardised effect size 0.34) as well as an indication of improvement in cognitive flexibility. Memory improvement predicted improvement in social functioning. Costs were lower in the cognitive remediation group following therapy but rose at follow-up. However, cost-effectiveness analyses showed that improvements in memory were achieved at little additional cost. Cognitive remediation therapy is associated with durable improvements in memory, which in turn are associated with social functioning improvements in people with severe mental illness.

Intensive cognitive-behavioural therapy for recent onset schizophrenia: A pilot study

Schizophrenia with an onset in adolescence is known to be associated with a poorer outcome and cognitive difficulties. These impairments have an impact on quality of life and represent treatment targets. Cognitive remediation therapy (CRT) attempts to improve cognitive deficits by teaching information processing strategies through guided mental exercises. The objective of this study is to evaluate the efficacy of CRT in alleviating cognitive deficits compared to treatment as usual and explore the mediating and moderating effects of cognitive improvement.Single-blind randomized controlled trial with two groups, one receiving CRT (N21) and the other standard care (N19) assessed at baseline, 3 months (post therapy) and follow-up (3 months post therapy). Participants were recruited from specialist inpatient and community mental health services and were young patients with recent onset schizophrenia (average age of 18) and evidence of cognitive and social behavioural difficulties. The intervention was individual cognitive remediation therapy delivered over a period of 3 months with at least three sessions per week. The main outcome measures were cognition (memory, cognitive flexibility and planning) and secondary outcomes (symptoms, social contacts and self-esteem).Compared to standard care, CRT produced significant additional improvements in cognitive flexibility as measured by the Wisconsin Card Sort Test (WCST). Therapy moderated the effects of improved planning ability on symptoms such that improvements only had a beneficial effect when they were achieved in the context of CRT. Improvements in cognition in all domains had a direct effect on social functioning and improvements in WCST had a direct effect on overall symptom improvement.Cognitive remediation therapy can contribute to the improvement in WCST even in adolescents. The changes in cognitive outcomes also contributed to improvements in functioning either directly or solely in the context of CRT. Evidence of the mediator and moderator effects of cognitive changes should lead to more effective therapy development.