-
The Cochrane Database of Systematic... Jul 2008Physical activity is beneficial for healthy ageing. It may also help maintain good cognitive function in older age. Aerobic activity improves cardiovascular fitness, but... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Physical activity is beneficial for healthy ageing. It may also help maintain good cognitive function in older age. Aerobic activity improves cardiovascular fitness, but it is not known whether this sort of fitness is necessary for improved cognitive function. Studies in which activity, fitness and cognition are reported in the same individuals could help to resolve this question.
OBJECTIVES
To assess the effectiveness of physical activity, aimed at improving cardiorespiratory fitness, on cognitive function in older people without known cognitive impairment.
SEARCH STRATEGY
We searched MEDLINE, EMBASE, PEDro, SPORTDiscus, PsycINFO, CINAHL, Cochrane Controlled Trials Register (CENTRAL), Dissertation abstracts international and ongoing trials registers on 15 December 2005 with no language restrictions.
SELECTION CRITERIA
All published randomised controlled trials comparing aerobic physical activity programmes with any other intervention or no intervention with participants older than 55 years of age were eligible for inclusion.
DATA COLLECTION AND ANALYSIS
Eleven RCTs fulfilling the inclusion criteria are included in this review. Two reviewers independently extracted the data from these included studies.
MAIN RESULTS
Eight out of 11 studies reported that aerobic exercise interventions resulted in increased cardiorespiratory fitness of the intervention group (an improvement on the maximum oxygen uptake test which is considered to be the single best indicator of the cardiorespiratory system) of approximately 14% and this improvement coincided with improvements in cognitive capacity. The largest effects on cognitive function were found on motor function and auditory attention (effect sizes of 1.17 and 0.50 respectively). Moderate effects were observed for cognitive speed (speed at which information is processed; effect size 0.26) and visual attention (effect size 0.26).
AUTHORS' CONCLUSIONS
There is evidence that aerobic physical activities which improve cardiorespiratory fitness are beneficial for cognitive function in healthy older adults, with effects observed for motor function, cognitive speed, auditory and visual attention. However, the majority of comparisons yielded no significant results. The data are insufficient to show that the improvements in cognitive function which can be attributed to physical exercise are due to improvements in cardiovascular fitness, although the temporal association suggests that this might be the case. Larger studies are still required to confirm whether the aerobic training component is necessary, or whether the same can be achieved with any type of physical exercise. At the same time, it would be informative to understand why some cognitive functions seem to improve with (aerobic) physical exercise while other functions seem to be insensitive to physical exercise. Clinicians and scientists in the field of neuropsychology should seek mutual agreement on a smaller battery of cognitive tests to use, in order to render research on cognition clinically relevant and transparent and heighten the reproducibility of results for future research.
Topics: Aged; Cognition; Cognition Disorders; Exercise; Humans; Memory; Middle Aged; Oxygen Consumption; Physical Fitness; Randomized Controlled Trials as Topic
PubMed: 18646126
DOI: 10.1002/14651858.CD005381.pub3 -
Frontiers in Psychology 2018Eye movement desensitization and reprocessing [EMDR] is an innovative, evidence-based and effective psychotherapy for post-traumatic stress disorder [PTSD]. As with...
Eye movement desensitization and reprocessing [EMDR] is an innovative, evidence-based and effective psychotherapy for post-traumatic stress disorder [PTSD]. As with other psychotherapies, the effectiveness of EMDR contrasts with a limited knowledge of its underlying mechanism of action. In its relatively short life as a therapeutic option, EMDR has not been without controversy, in particular regarding the role of the bilateral stimulation as an active component of the therapy. The high prevalence of EMDR in clinical practice and the dramatic increase in EMDR research in recent years, with more than 26 randomized controlled trials published to date, highlight the need for a better understanding of its mechanism of action. We conducted a thorough systematic search of studies published until January 2018, using PubMed, ScienceDirect, Web of Knowledge and Scopus databases that examined the mechanism of action of EMDR or provided conclusions within the framework of current theoretical models of EMDR functioning. Eighty-seven studies were selected for review and classified into three overarching models; (i) psychological models (ii) psychophysiological models and (iii) neurobiological models. The evidence available from each study was analyzed and discussed. Results demonstrated a reasonable empirical support for the working memory hypothesis and for the physiological changes associated with successful EMDR therapy. Recently, more sophisticated structural and functional neuroimaging studies using high resolution structural and temporal techniques are starting to provide preliminary evidence into the neuronal correlates before, during and after EMDR therapy. Despite the increasing number of studies that published in recent years, the research into the mechanisms underlying EMDR therapy is still in its infancy. Studies in well-defined clinical and non-clinical populations, larger sample sizes and tighter methodological control are further needed in order to establish firm conclusions.
PubMed: 30166975
DOI: 10.3389/fpsyg.2018.01395 -
The Cochrane Database of Systematic... Mar 2019The number of people living with dementia is increasing rapidly. Clinical dementia does not develop suddenly, but rather is preceded by a period of cognitive decline... (Meta-Analysis)
Meta-Analysis
BACKGROUND
The number of people living with dementia is increasing rapidly. Clinical dementia does not develop suddenly, but rather is preceded by a period of cognitive decline beyond normal age-related change. People at this intermediate stage between normal cognitive function and clinical dementia are often described as having mild cognitive impairment (MCI). Considerable research and clinical efforts have been directed toward finding disease-modifying interventions that may prevent or delay progression from MCI to clinical dementia.
OBJECTIVES
To evaluate the effects of at least 12 weeks of computerised cognitive training (CCT) on maintaining or improving cognitive function and preventing dementia in people with mild cognitive impairment.
SEARCH METHODS
We searched to 31 May 2018 in ALOIS (www.medicine.ox.ac.uk/alois) and ran additional searches in MEDLINE, Embase, PsycINFO, CINAHL, ClinicalTrials.gov, and the WHO portal/ICTRP (www.apps.who.int/trialsearch) to identify published, unpublished, and ongoing trials.
SELECTION CRITERIA
We included randomised controlled trials (RCTs) and quasi-RCTs in which cognitive training via interactive computerised technology was compared with an active or inactive control intervention. Experimental computerised cognitive training (CCT) interventions had to adhere to the following criteria: minimum intervention duration of 12 weeks; any form of interactive computerised cognitive training, including computer exercises, computer games, mobile devices, gaming console, and virtual reality. Participants were adults with a diagnosis of mild cognitive impairment (MCI) or mild neurocognitive disorder (MND), or otherwise at high risk of cognitive decline.
DATA COLLECTION AND ANALYSIS
Two review authors independently extracted data and assessed risk of bias of the included RCTs. We expressed treatment effects as mean differences (MDs) or standardised mean differences (SMDs) for continuous outcomes and as risk ratios (RRs) for dichotomous outcomes. We used the GRADE approach to describe the overall quality of evidence for each outcome.
MAIN RESULTS
Eight RCTs with a total of 660 participants met review inclusion criteria. Duration of the included trials varied from 12 weeks to 18 months. Only one trial used an inactive control. Most studies were at unclear or high risk of bias in several domains. Overall, our ability to draw conclusions was hampered by very low-quality evidence. Almost all results were very imprecise; there were also problems related to risk of bias, inconsistency between trials, and indirectness of the evidence.No trial provided data on incident dementia. For comparisons of CCT with both active and inactive controls, the quality of evidence on our other primary outcome of global cognitive function immediately after the intervention period was very low. Therefore, we were unable to draw any conclusions about this outcome.Due to very low quality of evidence, we were also unable to determine whether there was any effect of CCT compared to active control on our secondary outcomes of episodic memory, working memory, executive function, depression, functional performance, and mortality. We found low-quality evidence suggesting that there is probably no effect on speed of processing (SMD 0.20, 95% confidence interval (CI) -0.16 to 0.56; 2 studies; 119 participants), verbal fluency (SMD -0.16, 95% CI -0.76 to 0.44; 3 studies; 150 participants), or quality of life (mean difference (MD) 0.40, 95% CI -1.85 to 2.65; 1 study; 19 participants).When CCT was compared with inactive control, we obtained data on five secondary outcomes, including episodic memory, executive function, verbal fluency, depression, and functional performance. We found very low-quality evidence; therefore, we were unable to draw any conclusions about these outcomes.
AUTHORS' CONCLUSIONS
Currently available evidence does not allow us to determine whether or not computerised cognitive training will prevent clinical dementia or improve or maintain cognitive function in those who already have evidence of cognitive impairment. Small numbers of trials, small samples, risk of bias, inconsistency between trials, and highly imprecise results mean that it is not possible to derive any implications for clinical practice, despite some observed large effect sizes from individual studies. Direct adverse events are unlikely to occur, although the time and sometimes the money involved in computerised cognitive training programmes may represent significant burdens. Further research is necessary and should concentrate on improving methodological rigour, selecting suitable outcomes measures, and assessing generalisability and persistence of any effects. Trials with long-term follow-up are needed to determine the potential of this intervention to reduce the risk of dementia.
Topics: Aged; Cognition; Cognitive Dysfunction; Computer-Assisted Instruction; Dementia; Disease Progression; Executive Function; Humans; Memory, Episodic; Middle Aged; Quality of Life; Randomized Controlled Trials as Topic; Time Factors
PubMed: 30864747
DOI: 10.1002/14651858.CD012279.pub2 -
Journal of Integrative Neuroscience Sep 2023Patients with post-stroke memory disorder (PSMD) have poor quality of life and it is necessary to identify more beneficial stimulation protocols for treatment with... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Patients with post-stroke memory disorder (PSMD) have poor quality of life and it is necessary to identify more beneficial stimulation protocols for treatment with repetitive transcranial magnetic stimulation (rTMS). This meta-analysis was conducted to investigate the efficacy and safety of rTMS for improving memory performance, global cognition, and activities of daily living (ADL) among patients with PSMD.
METHODS
The PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), Chinese Biomedical Literature Database, Chinese National Knowledge Infrastructure, China Science and Technology Journal Database, and Wanfang databases were screened to identify relevant randomized controlled trials. The primary outcome was memory performance; secondary outcomes included global cognition, ADL, and adverse events. STATA software was used to perform data synthesis.
RESULTS
Five articles with a total of 192 participants were included. The results indicated that rTMS was superior to control treatments for improving memory performance (mean difference [MD] = 1.73, 95% CI [Confidence Interval] [0.85, 2.60], 0.001), global cognition (MD = 2.44, 95% CI [0.96, 3.93], 0.001), and ADL (MD = 10.29, 95% CI [5.10, 15.48], 0.001). No significant differences were found between the low-frequency (LF) and high-frequency (HF) rTMS subgroups ( 0.47, = 0.00%) or between the sham rTMS and non-rTMS subgroups ( 0.94, = 0.00%). Four studies did not reported adverse events.
CONCLUSIONS
rTMS may improve memory function, global cognition, and the ability to perform ADL in patients with PSMD. LF-rTMS and HF-rTMS may have equal efficacy for treatment of PSMD. Future studies should consider extending the follow-up period to explore the safety and long-term efficacy of rTMS for treatment of PSMD and the appropriate choice of placebo for clinical trials of this treatment.
Topics: Humans; Transcranial Magnetic Stimulation; Activities of Daily Living; Quality of Life; Memory Disorders; Memory; Stroke
PubMed: 37735134
DOI: 10.31083/j.jin2205131 -
Psychological Review Nov 2023Affective experiences are commonly represented by either transient emotional reactions to discrete events or longer term, sustained mood states that are characterized by...
Affective experiences are commonly represented by either transient emotional reactions to discrete events or longer term, sustained mood states that are characterized by a more diffuse and global nature. While both have considerable influence in shaping memory, their interaction can produce mood-congruent memory (MCM), a psychological phenomenon where emotional memory is biased toward content affectively congruent with a past or current mood. The study of MCM has direct implications for understanding how memory biases form in daily life, as well as debilitating negative memory schemas that contribute to mood disorders such as depression. To elucidate the factors that influence the presence and strength of MCM, here we systematically review the literature for studies that assessed MCM by inducing mood in healthy participants. We observe that MCM is often reported as enhanced accuracy for previously encoded mood-congruent content or preferential recall for mood-congruent autobiographical events, but may also manifest as false memory for mood-congruent lures. We discuss the relevant conditions that shape these effects, as well as instances of mood-incongruent recall that facilitate mood repair. Further, we provide guiding methodological and theoretical considerations, emphasizing the limited neuroimaging research in this area and the need for a renewed focus on memory consolidation. Accordingly, we propose a theoretical framework for studying the neural basis of MCM based on the neurobiological underpinnings of mood and emotion. In doing so, we review evidence for associative network models of spreading activation, while also considering alternative models informed by the cognitive neuroscience literature of emotional memory bias. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
Topics: Humans; Affect; Emotions; Mental Recall; Memory; Cognition
PubMed: 36201828
DOI: 10.1037/rev0000394 -
European Review For Medical and... Sep 2021We aimed this systematic review to analyze and review the currently available published literature related to long COVID, understanding its pattern, and predicting the...
We aimed this systematic review to analyze and review the currently available published literature related to long COVID, understanding its pattern, and predicting the long-term effects on survivors. We thoroughly searched the databases for relevant articles till May 2021. The research articles that met our inclusion and exclusion criteria were assessed and reviewed by two independent researchers. After preliminary screening of the identified articles through title and abstract, 249 were selected. Consequently, 167 full-text articles were assessed and reviewed based on our inclusion criteria and thus 20 articles were regarded as eligible and analyzed in the present analysis. All the studies included adult population aged between 18 and above 60 years. The median length of hospital stay of the COVID-19 patients during the acute infection phase ranged from 8 days to 17 days. The most common prevalent long-term symptoms in COVID-19 patients included persistent fatigue and dyspnea in almost all of the studies. Other reported common symptoms included: shortness of breath, cough, joint pain, chest pain or tightness, headache, loss of smell/taste, sore throat, diarrhea, loss of memory, depression, anxiety. Associated cardiovascular events included arrhythmias, palpitations and hypotension, increased HR, venous thromboembolic diseases, myocarditis, and acute/decompensated heart failure as well. Among neurological manifestations headache, peripheral neuropathy symptoms, memory issues, concentration, and sleep disorders were most commonly observed with varying frequencies. Mental health issues affecting mental abilities, mood fluctuations namely anxiety and depression, and sleep disorders were commonly seen. Further, diarrhea, vomiting, digestive disorders, and Loss of appetite or weight loss are common gastrointestinal manifestations. Therefore, appropriate clinical evaluation is required in long COVID cases which in turn may help us to identify the risk factors, etiology, and to my help, we treat them early with appropriate management strategies.
Topics: COVID-19; Humans; SARS-CoV-2; Post-Acute COVID-19 Syndrome
PubMed: 34533807
DOI: 10.26355/eurrev_202109_26669 -
The Cochrane Database of Systematic... Nov 2018Vitamins and minerals have many functions in the nervous system which are important for brain health. It has been suggested that various different vitamin and mineral... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Vitamins and minerals have many functions in the nervous system which are important for brain health. It has been suggested that various different vitamin and mineral supplements might be useful in maintaining cognitive function and delaying the onset of dementia. In this review, we sought to examine the evidence for this in people who already had mild cognitive impairment (MCI).
OBJECTIVES
To evaluate the effects of vitamin and mineral supplementation on cognitive function and the incidence of dementia in people with mild cognitive impairment.
SEARCH METHODS
We searched ALOIS, the Cochrane Dementia and Cognitive Improvement Group's (CDCIG) specialised register, as well as MEDLINE, Embase, PsycINFO, CENTRAL, CINAHL, LILACs, Web of Science Core Collection, ClinicalTrials.gov, and the WHO Portal/ICTRP, from inception to 25 January 2018.
SELECTION CRITERIA
We included randomised or quasi-randomised, placebo-controlled trials which evaluated orally administered vitamin or mineral supplements in participants with a diagnosis of mild cognitive impairment and which assessed the incidence of dementia or cognitive outcomes, or both. We were interested in studies applicable to the general population of older people and therefore excluded studies in which participants had severe vitamin or mineral deficiencies.
DATA COLLECTION AND ANALYSIS
We sought data on our primary outcomes of dementia incidence and overall cognitive function and on secondary outcomes of episodic memory, executive function, speed of processing, quality of life, functional performance, clinical global impression, adverse events, and mortality. We conducted data collection and analysis according to standard Cochrane systematic review methods. We assessed the risk of bias of included studies using the Cochrane 'Risk of bias' assessment tool. We grouped vitamins and minerals according to their putative mechanism of action and, where we considered it to be clinically appropriate, we pooled data using random-effects methods. We used GRADE methods to assess the overall quality of evidence for each comparison and outcome.
MAIN RESULTS
We included five trials with 879 participants which investigated B vitamin supplements. In four trials, the intervention was a combination of vitamins B6, B12, and folic acid; in one, it was folic acid only. Doses varied. We considered there to be some risks of performance and attrition bias and of selective outcome reporting among these trials. Our primary efficacy outcomes were the incidence of dementia and scores on measures of overall cognitive function. None of the trials reported the incidence of dementia and the evidence on overall cognitive function was of very low-quality. There was probably little or no effect of B vitamins taken for six to 24 months on episodic memory, executive function, speed of processing, or quality of life. The evidence on our other secondary clinical outcomes, including harms, was very sparse or very low-quality. There was evidence from one study that there may be a slower rate of brain atrophy over two years in participants taking B vitamins. The same study reported subgroup analyses based on the level of serum homocysteine (tHcy) at baseline and found evidence that B vitamins may improve episodic memory in those with tHcy above the median at baseline.We included one trial (n = 516) of vitamin E supplementation. Vitamin E was given as 1000 IU of alpha-tocopherol twice daily. We considered this trial to be at risk of attrition and selective reporting bias. There was probably no effect of vitamin E on the probability of progression from MCI to Alzheimer's dementia over three years (HR 1.02; 95% CI 0.74 to 1.41; n = 516; 1 study, moderate-quality evidence). There was also no evidence of an effect at intermediate time points. The available data did not allow us to conduct analyses, but the authors reported no significant effect of three years of supplementation with vitamin E on overall cognitive function, episodic memory, speed of processing, clinical global impression, functional performance, adverse events, or mortality (five deaths in each group). We considered this to be low-quality evidence.We included one trial (n = 256) of combined vitamin E and vitamin C supplementation and one trial (n = 26) of supplementation with chromium picolinate. In both cases, there was a single eligible cognitive outcome, but we considered the evidence to be very low-quality and so could not be sure of any effects.
AUTHORS' CONCLUSIONS
The evidence on vitamin and mineral supplements as treatments for MCI is very limited. Three years of treatment with high-dose vitamin E probably does not reduce the risk of progression to dementia, but we have no data on this outcome for other supplements. Only B vitamins have been assessed in more than one RCT. There is no evidence for beneficial effects on cognition of supplementation with B vitamins for six to 24 months. Evidence from a single study of a reduced rate of brain atrophy in participants taking vitamin B and a beneficial effect of vitamin B on episodic memory in those with higher tHcy at baseline warrants attempted replication.
Topics: Aged; Aged, 80 and over; Ascorbic Acid; Cognition; Cognition Disorders; Dementia; Dietary Supplements; Executive Function; Humans; Memory, Episodic; Middle Aged; Mortality; Picolinic Acids; Quality of Life; Randomized Controlled Trials as Topic; Trace Elements; Vitamin B Complex; Vitamins; alpha-Tocopherol
PubMed: 30383288
DOI: 10.1002/14651858.CD011905.pub2 -
Comprehensive Psychiatry Oct 2023Converging evidence supports that gaming and gambling disorders are associated with executive dysfunction. The involvement of different components of executive functions... (Review)
Review
BACKGROUND
Converging evidence supports that gaming and gambling disorders are associated with executive dysfunction. The involvement of different components of executive functions (EF) in these forms of behavioural addiction is unclear.
AIM
In a systematic review, we aim to uncover the association between working memory (WM), a crucial component of EF, and disordered gaming and gambling. Note that, in the context of this review, gaming has been used synonymously with video gaming.
METHODS
Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), we systematically searched for studies published from 2012 onwards.
RESULTS
The search yielded 6081 records after removing duplicates, from which 17 peer-reviewed journal articles were eligible for inclusion. The association between WM and problem or disordered gaming and gambling have been categorized separately to observe possible differences. Essentially, problem gaming or gambling, compared to disorder, presents lesser severity and clinical significance. The results demonstrate reduced auditory-verbal WM in individuals with gambling disorder. Decreased WM capacity was also associated with problem gambling, with a correlation between problem gambling severity and decreased WM capacity. Similarly, gaming disorder was associated with decreased WM. Specifically, gaming disorder patients had lower WM capacity than the healthy controls.
CONCLUSION
Working memory seems to be a significant predictor of gambling and gaming disorders. Therefore, holistic treatment approaches that incorporate cognitive techniques that could enhance working memory may significantly boost gambling and gaming disorders treatment success.
Topics: Humans; Gambling; Memory, Short-Term; Cognition; Disruptive, Impulse Control, and Conduct Disorders; Video Games; Behavior, Addictive
PubMed: 37573802
DOI: 10.1016/j.comppsych.2023.152408 -
Psychopharmacology Mar 2022±3,4-Methylenedioxymethamphetamine (MDMA) is a recreational drug that shows substantial promise as a psychotherapeutic agent. Still, there is some concern regarding its... (Review)
Review
RATIONALE
±3,4-Methylenedioxymethamphetamine (MDMA) is a recreational drug that shows substantial promise as a psychotherapeutic agent. Still, there is some concern regarding its behavioral toxicity, and its dose-effect relationship is poorly understood. We previously explored the role of dose in the cognitive effects of MDMA in a systematic review of existing literature and found no evidence in animals that MDMA impairs memory at low doses (< 3 mg/kg) but mixed results at high doses (≥ 3 mg/kg). Since this review comprised mostly of single-dose studies and an assortment of methodologies, an empirical dose-ranging study on this topic is warranted.
OBJECTIVES
The current study aims to evaluate the conclusion from our systematic review that 3 mg/kg may be the threshold for MDMA-induced amnesia, and to further understand the dose-effect relationship of MDMA on behavioral assays of memory, addiction, and depression.
METHODS
We systematically examined the effects of 0.01 to 10 mg/kg MDMA on Pavlovian fear conditioning; behavioral sensitization, conditioned place preference, and conditioned responding; and the Porsolt forced swim test in mice.
RESULTS
High doses of MDMA (≥ 3 mg/kg) produced amnesia of fear conditioning memory, some evidence of an addictive potential, and antidepressant effects, while low doses of MDMA (≤ 1 mg/kg) had no effect on these behaviors.
CONCLUSIONS
The present dose-ranging study provides further evidence that 3 mg/kg is the threshold for MDMA-induced amnesia. These findings, in addition to our systematic review, demonstrate that careful selection of MDMA dose is critical. High doses (≥ 3 mg/kg) should likely be avoided due to evidence that they can produce amnesia and addiction. Conversely, there is little evidence to suggest that low doses, which are usually administered in clinical studies (approximately 1-2 mg/kg), will lead to these same adverse effects. Ultra-low doses (< 1 mg/kg) are likely even safer and should be investigated for therapeutic effects in future studies.
Topics: Amnesia; Animals; Conditioning, Classical; Depression; Dose-Response Relationship, Drug; Fear; Mice; N-Methyl-3,4-methylenedioxyamphetamine
PubMed: 35179622
DOI: 10.1007/s00213-022-06086-9