Effects of chronic physical exercise on executive functions and episodic memory in clinical and healthy older adult populations: a systematic review and meta-analysis protocol.

BACKGROUND: Executive functions (EFs) and episodic memory are fundamental components of cognition that deteriorate with age and are crucial for independent living. While numerous reviews have explored the effect of exercise on these components in old age, these reviews screened and analyzed selected older adult populations, or specific exercise modes, thus providing only limited answers to the fundamental question on the effect of exercise on cognition in old age. This article describes the protocol for a systematic review and multilevel meta-analytic study aiming at evaluating the effectiveness of different types of chronic exercise in improving and/or maintaining EFs and long-term episodic memory in older adults. METHODS AND ANALYSIS: The study protocol was written in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Several databases will be searched. Randomized controlled trials (RCTs) conducted in older adults aged ≥ 60 years providing any kind of planned, structured, and repetitive exercise interventions, and EFs and/or episodic memory measures as outcomes, published in English in peer-reviewed journals and doctoral dissertations will be included. Two independent reviewers will screen the selected articles, while a third reviewer will resolve possible conflicts. The Cochrane risk-of-bias tool will be used to assess the quality of the studies. Finally, data will be extracted from the selected articles, and the formal method of combining individual data from the selected studies will be applied using a random effect multilevel meta-analysis. The data analysis will be conducted with the metafor package in R. DISCUSSION AND CONCLUSION: This review will synthesize the existing evidence and pinpoint gaps existing in the literature on the effects of exercise on EFs and episodic memory in healthy and unhealthy older adults. Findings from this meta-analysis will help to design effective exercise interventions for older adults to improve and/or maintain EFs and episodic memory. Its results will be useful for many researchers and professionals working with older adults and their families. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42022367111.

The Effects of Combined Cognitive-Physical Interventions on Cognitive Functioning in Healthy Older Adults: A Systematic Review and Multilevel Meta-Analysis.

Research has shown that both physical exercise and cognitive training help to maintain cognition in older adults. The question is whether combined training might produce additive effects when the group comparisons are equated in terms of exercise intensity and modality. We conducted a systematic electronic search in MEDLINE, PsycInfo, and Cochrane Central Register of Controlled Trials (CENTRAL) databases to identify relevant studies published up to February 2021. Seven hundred and eighty-three effect sizes were obtained from 50 published intervention studies, involving 6,164 healthy older adults, and submitted to a three-level meta-analysis. Results showed that combined training produced a small advantage in comparison to single cognitive training on executive functions, whereas both types of training achieved similar effects on attention, memory, language, processing speed, and global cognition. Combined training achieved higher training gains in balance than single physical training, indicating a transfer from cognitive training to balance. Performing cognitive and physical exercise simultaneously, and interactive training (e.g., exergames, square stepping) produced the largest gains in executive functions, speed, and global cognition, as well as the largest improvements in physical functions. Aerobic training was associated with higher effects in attention and fitness, whereas non-aerobic training produced larger effects in global cognition and balance. For all cognitive and physical outcomes, training resulted more advantageous when performed in a social context, even though individual training obtained similar results in balance as group training. Systematic Review Registration: www.crd.york.ac.uk/prospero/, identifier: CRD42020175632.

Efficacy of binaural auditory beats in cognition, anxiety, and pain perception: a meta-analysis.

Binaural auditory beats are a perceptual phenomenon that occurs when presenting separately to each ear two tones that slightly differ in their frequency. It has been suggested that binaural beats can influence cognition and mental states among others. The objective of this meta-analysis was to study the effect of binaural beats on memory, attention, anxiety, and analgesia. Twenty-two studies met our inclusion criteria for this meta-analysis. The results, based on 35 effect sizes, showed an overall medium, significant, consistent effect size (g = 0.45). Meta-regression results indicated that it does not seem to be necessary to mask binaural beats with white noise or pink noise in terms of effectiveness, obtaining similar effects with unmasked binaural beats. Moreover, the findings suggest that binaural-beat exposure before, and before and during the task produces superior results than exposure during the task. Time under exposure contributed significantly to the model indicating that longer periods are advisable to ensure maximum effectiveness. Our meta-analysis adds to the growing evidence that binaural-beat exposure is an effective way to affect cognition over and above reducing anxiety levels and the perception of pain without prior training, and that the direction and the magnitude of the effect depends upon the frequency used, time under exposure, and the moment in which the exposure takes place.

Binaural auditory beats affect long-term memory.

The presentation of two pure tones to each ear separately with a slight difference in their frequency results in the perception of a single tone that fluctuates in amplitude at a frequency that equals the difference of interaural frequencies. This perceptual phenomenon is known as binaural auditory beats, and it is thought to entrain electrocortical activity and enhance cognition functions such as attention and memory. The aim of this study was to determine the effect of binaural auditory beats on long-term memory. Participants (n = 32) were kept blind to the goal of the study and performed both the free recall and recognition tasks after being exposed to binaural auditory beats, either in the beta (20 Hz) or theta (5 Hz) frequency bands and white noise as a control condition. Exposure to beta-frequency binaural beats yielded a greater proportion of correctly recalled words and a higher sensitivity index d' in recognition tasks, while theta-frequency binaural-beat presentation lessened the number of correctly remembered words and the sensitivity index. On the other hand, we could not find differences in the conditional probability for recall given recognition between beta and theta frequencies and white noise, suggesting that the observed changes in recognition were due to the recollection component. These findings indicate that the presentation of binaural auditory beats can affect long-term memory both positively and negatively, depending on the frequency used.

Taste priming and cross-modal taste-olfactory priming in normal aging and in older adults with mild cognitive impairment.

BACKGROUND: Previous research has shown repetition priming for objects between vision and touch, environmental sounds and pictures in young and older adults. METHODS: This preliminary study investigated whether repetition priming exists for edible stimuli and if it is preserved in healthy older adults and older adults with mild cognitive impairment (MCI) (Experiment 1). Experiment 2 investigated whether cross-modal repetition priming between taste and olfaction is preserved with age and cognitive impairment. RESULTS: The results of Experiment 1 showed significant repetition priming effects for edible stimuli presented to taste, but there was a significant decrease in performance with age and cognitive decline. Experiment 2 showed cross-modal taste to olfactory priming in young adults and healthy older people, but the performance of older adults with MCI did not differ from zero. Again, identification decreased significantly in older adults and was absent in those with MCI. CONCLUSIONS: Implicit memory for stimuli presented to taste persists in healthy older adults and those with MCI, although their performance declined compared to young adults. The finding of cross-modal taste and olfactory priming suggests the connection between these two chemosensory perceptual modalities.

Effects of age and type of picture on visuospatial working memory assessed with a computerized jigsaw-puzzle task.

We investigated the effect of age and color in a computerized version of the jigsaw-puzzle task. In Experiment 1, young and older adults were presented with puzzles in color and black-and-white line drawings, varying in difficulty from 4 to 9 pieces. Older adults performed the task better with the black-and-white stimuli and younger adults performed better with the color ones. In Experiment 2, new older and young adults identified the same fragmented pictures as fast and accurately as possible. The older group identified the black-and-white stimuli faster than those presented in color, while the younger adults identified both similarly. In Experiment 3A, new older and young groups performed the puzzle task with the same color pictures and their monochrome versions. In Experiment 3B, participants performed a speeded identification task with the two sets. The findings of these experiments showed that older adults have a memory not a perceptual difficulty.

Effects of Video Game Training on Measures of Selective Attention and Working Memory in Older Adults: Results from a Randomized Controlled Trial.

Video game training with older adults potentially enhances aspects of cognition that decline with aging and could therefore offer a promising training approach. Although, previous published studies suggest that training can produce transfer, many of them have certain shortcomings. This randomized controlled trial (RCT; Clinicaltrials.gov ID: NCT02796508) tried to overcome some of these limitations by incorporating an active control group and the assessment of motivation and expectations. Seventy-five older volunteers were randomly assigned to the experimental group trained for 16 sessions with non-action video games from Lumosity, a commercial platform (http://www.lumosity.com/) or to an active control group trained for the same number of sessions with simulation strategy games. The final sample included 55 older adults (30 in the experimental group and 25 in the active control group). Participants were tested individually before and after training to assess working memory (WM) and selective attention and also reported their perceived improvement, motivation and engagement. The results showed improved performance across the training sessions. The main results were: (1) the experimental group did not show greater improvements in measures of selective attention and working memory than the active control group (the opposite occurred in the oddball task); (2) a marginal training effect was observed for the N-back task, but not for the Stroop task while both groups improved in the Corsi Blocks task. Based on these results, one can conclude that training with non-action games provide modest benefits for untrained tasks. The effect is not specific for that kind of training as a similar effect was observed for strategy video games. Groups did not differ in motivation, engagement or expectations.

Video Game Training Enhances Visuospatial Working Memory and Episodic Memory in Older Adults.

In this longitudinal intervention study with experimental and control groups, we investigated the effects of video game training on the visuospatial working memory (WM) and episodic memory of healthy older adults. Participants were 19 volunteer older adults, who received 15 1-h video game training sessions with a series of video games selected from a commercial package (Lumosity), and a control group of 20 healthy older adults. The results showed that the performance of the trainees improved significantly in all the practiced video games. Most importantly, we found significant enhancements after training in the trained group and no change in the control group in two computerized tasks designed to assess visuospatial WM, namely the Corsi blocks task and the Jigsaw puzzle task. The episodic memory and short-term memory of the trainees also improved. Gains in some WM and episodic memory tasks were maintained during a 3-month follow-up period. These results suggest that the aging brain still retains some degree of plasticity, and that video game training might be an effective intervention tool to improve WM and other cognitive functions in older adults.

Corrigendum: Brain training with non-action video games enhances aspects of cognition in older adults: a randomized controlled trial.

[This corrects the article on p. 277 in vol. 6, PMID: 25352805.].

A randomized controlled trial of brain training with non-action video games in older adults: results of the 3-month follow-up.

This randomized controlled study (ClinicalTrials.gov NCT02007616) investigated the maintenance of training effects of 20 1-hr non-action video game training sessions with selected games from a commercial package on several age-declining cognitive functions and subjective wellbeing after a 3-month no-contact period. Two groups of cognitively normal older adults participated in both the post-training (posttest) and the present follow-up study, the experimental group who received training and the control group who attended several meetings with the research team during the study but did not receive training. Groups were similar at baseline on demographics, vocabulary, global cognition, and depression status. Significant improvements in the trained group, and no variation in the control group had been previously found at posttest, in processing speed, attention and visual recognition memory, as well as in two dimensions of subjective wellbeing. In the current study, improvement from baseline to 3 months follow-up was found only in wellbeing (Affection and Assertivity dimensions) in the trained group whereas there was no change in the control group. Previous significant improvements in processing speed, attention and spatial memory become non-significant after the 3-month interval. Training older adults with non-action video games enhanced aspects of cognition just after training but this effect disappeared after a 3-month no-contact follow-up period. Cognitive plasticity can be induced in older adults by training, but to maintain the benefits periodic boosting sessions would be necessary.

Brain training with non-action video games enhances aspects of cognition in older adults: a randomized controlled trial.

Age-related cognitive and brain declines can result in functional deterioration in many cognitive domains, dependency, and dementia. A major goal of aging research is to investigate methods that help to maintain brain health, cognition, independent living and wellbeing in older adults. This randomized controlled study investigated the effects of 20 1-h non-action video game training sessions with games selected from a commercially available package (Lumosity) on a series of age-declined cognitive functions and subjective wellbeing. Two groups of healthy older adults participated in the study, the experimental group who received the training and the control group who attended three meetings with the research team along the study. Groups were similar at baseline on demographics, vocabulary, global cognition, and depression status. All participants were assessed individually before and after the intervention, or a similar period of time, using neuropsychological tests and laboratory tasks to investigate possible transfer effects. The results showed significant improvements in the trained group, and no variation in the control group, in processing speed (choice reaction time), attention (reduction of distraction and increase of alertness), immediate and delayed visual recognition memory, as well as a trend to improve in Affection and Assertivity, two dimensions of the Wellbeing Scale. Visuospatial working memory (WM) and executive control (shifting strategy) did not improve. Overall, the current results support the idea that training healthy older adults with non-action video games will enhance some cognitive abilities but not others.

Video game training enhances cognition of older adults: a meta-analytic study.

It has been suggested that video game training enhances cognitive functions in young and older adults. However, effects across studies are mixed. We conducted a meta-analysis to examine the hypothesis that training healthy older adults with video games enhances their cognitive functioning. The studies included in the meta-analysis were video game training interventions with pre- and posttraining measures. Twenty experimental studies published between 1986 and 2013, involving 474 trained and 439 healthy older controls, met the inclusion criteria. The results indicate that video game training produces positive effects on several cognitive functions, including reaction time (RT), attention, memory, and global cognition. The heterogeneity test did not show a significant heterogeneity (I(2) = 20.69%) but this did not preclude a further examination of moderator variables. The magnitude of this effect was moderated by methodological and personal factors, including the age of the trainees and the duration of the intervention. The findings suggest that cognitive and neural plasticity is maintained to a certain extent in old age. Training older adults with video games enhances several aspects of cognition and might be a valuable intervention for cognitive enhancement.

An electrophysiological study of haptic roughness: effects of levels of texture and stimulus uncertainty in the P300.

This study investigated the neural mechanisms implicated in tactile perception using a discrimination task. We also investigated the influence of the type of presentation on the subject's uncertainty. The stimuli varied across four levels of roughness and were presented using a pure/mixed block design. We used an oddball paradigm with three target stimuli varying in the level of roughness, and a smooth surface as the non-target. Stimuli were presented using a specific-purpose device. We analyzed the modulation of the P300 amplitude elicited by targets and non-targets in both presentation conditions. The results showed that the P300 waveform was modulated by roughness, as well as by the order of stimuli presentation. The P300 amplitude was more sensitive to roughness when stimuli were presented in mixed blocks (higher uncertainty). The results are discussed in the context of the attention resources allocation theory applied to tactile modality.

Lack of pattern of birth in patients with bulimia nervosa.

OBJECTIVE: An excess of bulimia nervosa (BN) births during the fall has been recently reported, but this finding has not been yet adequately replicated. The purpose of our study was to evaluate the presence of a seasonal birth pattern in a representative clinical sample of women with BN. METHOD: We registered the month of birth of 216 female patients who fulfilled all the criteria for BN according to DSM-IV on admission to a specialized eating disorders service in Spain. RESULTS: Our analyses showed no significant variation in the season of birth of our BN sample when compared to a general population. DISCUSSION: Our data do not support the hypothesis of a season of birth bias in BN.

Absence of seasonal pattern of birth in patients with anorexia nervosa.

OBJECTIVE: An excess of spring births has been suggested in patients with anorexia nervosa (AN), especially in the restricting subtype, but most of the research has been carried out inside the United Kingdom. The aim of this study was to assess whether there is a seasonal pattern of birth in a representative sample of patients with AN in a different latitude in the northern hemisphere. METHOD: We examined the month of birth in a sample of 210 female patients with a DSM-IV diagnosis of AN at first presentation to a specialized eating disorders service in Spain. RESULTS: We found no evidence of significant variation in month or season of birth in AN when compared to general population. DISCUSSION: There is not enough evidence of a season of birth bias under the latitude of the United Kingdom in the risk of developing AN.

Ageing affects event-related potentials and brain oscillations: a behavioral and electrophysiological study using a haptic recognition memory task.

In this electrophysiological study, we investigated the effects of ageing on recognition memory for three-dimensional (3D) familiar objects presented to touch in a continuous paradigm. To examine changes in event-related potentials (ERPs) and brain oscillations, we recorded the EEGs of healthy groups of young (n=14; mean age=32.3 years) and older adults (n=14; mean age=65.1). Both age groups exhibited similar accuracy and exploration times when making old-new judgments. Young and older participants showed a marginally significant ERP old/new effect widely distributed over the scalp between 550-750 ms. In addition, the elders showed lower amplitude than younger participants within 1200-1500 ms. There were age-related differences in brain oscillations as measured by event-related spectral perturbation (ERSP). Older adults showed greater alpha and beta power reductions than young participants, suggesting the recruitment of additional neural resources. In contrast, the two age groups showed a reliable old/new effect in the theta band that temporarily overlapped the ERP old/new effect. The present results suggest that despite similar behavioral performance, the young and older adults recruited different neural resources to perform a haptic recognition task.

Memoria implícita y explícita en mayores no dementes con trastornos metabólicos producidos por la diabetes mellitus tipo 2 / No disponible

En este estudio hemos investigado si la memoria implícita de palabras seencuentra preservada en el envejecimiento normal y en el envejecimientocon diabetes mellitus. El estudio también ha evaluado la posible disociaciónentre dos formas de acceder a la información previamente codificada,implícita y explícita. Los resultados han mostrado un priming de repeticiónsimilar en los tres grupos que han participado en el estudio (adultos jóvenes,mayores sanos y pacientes diabéticos). Por el contrario, los tres grupos handiferido en la capacidad de su memoria de reconocimiento. La memoriaexplícita se encuentra deteriorada en el grupo de mayores diabéticos conrespecto a los mayores sanos. Además, los adultos jóvenes actuaron mejorque los dos grupos de mayores. El mantenimiento del priming visual depalabras en pacientes diabéticos y mayores sanos en relación al primingobtenido por los adultos jóvenes apoya la idea de que la memoria implícitadepende de un sistema de memoria perceptivo diferente del sistematemporal medio del que depende la memoria explícita(AU)

Selective attention modulates visual and haptic repetition priming: effects in aging and Alzheimer's disease.

In two experiments, we examined the effect of selective attention at encoding on repetition priming in normal aging and Alzheimer's disease (AD) patients for objects presented visually (experiment 1) or haptically (experiment 2). We used a repetition priming paradigm combined with a selective attention procedure at encoding. Reliable priming was found for both young adults and healthy older participants for visually presented pictures (experiment 1) as well as for haptically presented objects (experiment 2). However, this was only found for attended and not for unattended stimuli. The results suggest that independently of the perceptual modality, repetition priming requires attention at encoding and that perceptual facilitation is maintained in normal aging. However, AD patients did not show priming for attended stimuli, or for unattended visual or haptic objects. These findings suggest an early deficit of selective attention in AD. Results are discussed from a cognitive neuroscience approach.

Picture priming in normal aging and Alzheimers disease

The present study investigated age invariance for naming pictures and whether implicit memory is spared in Alzheimers disease (AD). During the study phase, young adults, AD patients, and older controls were shown outlines of familiar pictures. After a distracter task, implicit memory was assessed incidentally. The results showed similar visual priming for the three groups, although young adults responded faster than the two older groups. Moreover, the number of errors was smaller for studied than for nonstudied pictures. This pattern of results was repeated across the three groups, although AD patients produced more errors than young adults and older controls, and there were no differences between these latter groups. These results confirmed previous visual and haptic findings showing unimpaired perceptual priming in normal aging and AD patients when implicit memory is assessed using identification tasks. These results are interpreted from a cognitive neuroscience perspective

El trabajo estudió la existencia de priming perceptivo invariante con la edad y si la memoria implícita se mantiene en enfermos de Alzheimer (EA). Presentamos a adultos jóvenes, enfermos de Alzheimer (AD) y mayores controles durante la fase de estudio siluetas de dibujos familiares. Después de realizar una tarea distractora, evaluamos su memoria implícita de manera incidental. Los resultados mostraron un priming perceptivo similar en los tres grupos, aunque los jóvenes respondieron más de prisa que los dos grupos de mayores. Además, el número de errores fue menor en los tres grupos para los estímulos estudiados que para los no estudiados. Estos resultados confirman resultados visuales y hápticos previos y sugieren la existencia de priming perceptivo normal, invariante con la edad y la demencia, cuando la memoria implícita se evalúa con tareas de identificación perceptiva. Estos resultados se interpretan desde la perspectiva de la neurociencia cognitiva