Treadmill walking during vocabulary encoding improves verbal long-term memory

Amplitude envelope onset characteristics modulate phase locking for speech auditory-motor synchronization

The spontaneous speech-to-speech synchronization (SSS) test has been shown to be an effective behavioral method to estimate cortical speech auditory-motor coupling strength through phase-locking value (PLV) between auditory input and motor output. This study further investigated how amplitude envelope onset variations of the auditory speech signal may influence the speech auditory-motor synchronization. Sixty Mandarin-speaking adults listened to a stream of randomly presented syllables at an increasing speed while concurrently whispering in synchrony with the rhythm of the auditory stimuli whose onset consistency was manipulated, consisting of aspirated, unaspirated, and mixed conditions. The participants' PLVs for the three conditions in the SSS test were derived and compared. Results showed that syllable rise time affected the speech auditory-motor synchronization in a bifurcated fashion. Specifically, PLVs were significantly higher in the temporally more consistent conditions (aspirated or unaspirated) than those in the less consistent condition (mixed) for high synchronizers. In contrast, low synchronizers tended to be immune to the onset consistency. Overall, these results validated how syllable onset consistency in the rise time of amplitude envelope may modulate the strength of speech auditory-motor coupling. This study supports the application of the SSS test to examine individual differences in the integration of perception and production systems, which has implications for those with speech and language disorders that have difficulty with processing speech onset characteristics such as rise time.

Mutual interference between memory encoding and motor skills: the influence of motor expertise

In cognitive-motor dual-task situations, the extent of performance decrements is influenced by the attentional requirements of each task. Well-learned motor skills should be automatized, leading to less interference. This study presents two studies combining an episodic memory encoding task with well-practiced motor tasks in athletes. Study 1 asked 40 rowers (early teenagers to middle adulthood) to row on ergometers at slow or fast speeds. In study 2, Taekwondo athletes (n = 37) of different skill levels performed a well-practiced sequence of martial arts movements. Performing the motor task during encoding led to pronounced performance reductions in memory in both studies, with costs of up to 80%. Cognitive costs were even larger when rowing with the fast compared to the slow speed in study 1. Both studies also revealed decrements in motor performances under dual-task conditions: Rowing became slower and more irregular (study 1), and the quality of the Taekwondo performance was reduced. Although higher-level athletes outperformed others in motor skills under single-task conditions, proportional dual-task costs were similar across skill levels for most domains. This indicates that even well-practiced motor tasks require cognitive resources.

Epigenetic modification impacting brain functions: Effects of physical activity, micronutrients, caffeine, toxins, and addictive substances

Changes in gene expression are involved in many brain functions. Epigenetic processes modulate gene expression by histone modification and DNA methylation or RNA-mediated processes, which is important for brain function. Consequently, epigenetic changes are also a part of brain diseases such as mental illness and addiction. Understanding the role of different factors on the brain epigenome may help us understand the function of the brain. This review discussed the effects of caffeine, lipids, addictive substances, physical activity, and pollutants on the epigenetic changes in the brain and their modulatory effects on brain function.

The brain in motion-cognitive effects of simultaneous motor activity

During the last 30 years, a large number of behavioral studies have investigated the effect of simultaneous exercise on cognitive functions. The heterogeneity of the results has been attributed to different parameters, such as intensity or modality of physical activity, and the investigated cognitive processes. More recent methodological improvements have enabled to record electroencephalography (EEG) during physical exercise. EEG studies combining cognitive tasks with exercise have described predominantly detrimental effects on cognitive processes and EEG parameters. However, differences in the underlying rationale and the design of EEG versus behavioral studies make direct comparisons between both types of studies difficult. In this narrative review of dual-task experiments we evaluated behavioral and EEG studies and discuss possible explanations for the heterogeneity of results and for the discrepancy between behavioral and EEG studies. Furthermore, we provide a proposal for future EEG studies on simultaneous motion to be a useful complement to behavioral studies. A crucial factor might be to find for each cognitive function the motor activity that matches this function in terms of attentional focus. This hypothesis should be investigated systematically in future studies.

Stress can lead to an increase in smartphone use in the context of texting while walking

Texting while walking (TWW) is a dangerous behavior that can lead to injury and even death. While several studies have examined the relationship between smartphone use and stress, to our knowledge no studies have yet investigated the relationship between stress and TWW. The objective of the present study was to investigate this relationship by examining the effects of stress on TWW, the effects of TWW on subsequent stress, and the effect of stress on multitasking performance. A total of 80 participants completed two sequential tasks in a laboratory while they walked on a treadmill and responded to a biological motion stimulus imitating the movement of another pedestrian. In the unrestricted task, participants were given the choice to use their personal phones. In the controlled task, they carried a text conversation with a research assistant while they walked and responded to the stimulus. Stress was measured via questionnaire and saliva collection for measure of cortisol (a stress hormone) before and after each task. Results show that greater psychological stress and cortisol variations were associated with a greater number of phone uses during the unrestricted task. Greater phone use during the unrestricted task was associated with lower subsequent psychological stress in women and total time of phone use was correlated with subsequent cortisol levels. Stress measured before the controlled task had no effect on multitasking performance, but participants with moderate performance were those with the highest cortisol levels. Our results suggest that stress could be a precursor to TWW and that it could affect a pedestrian’s ability to stay safe when using their smartphone.

The Effects of Acute Cardiovascular Exercise on Memory and Its Associations With Exercise-Induced Increases in Neurotrophic Factors

Due to increasing life expectancy, low-cost interventions to counteract age-related memory impairment have gained popularity. Physical activity has been shown to positively affect memory and hippocampal plasticity in rodents and humans. These effects have been proposed to be mediated by the release of neurotrophic factors. However, studies examining the effects of a single cardiovascular exercise session on human memory have yielded conflicting results. Moreover, it remains unclear whether exercise-induced memory enhancements are related to changes in peripheral neurotrophic factor concentrations. The present study tested whether one bout of cardiovascular exercise during an early phase of memory consolidation, compared to one bout of stretching and toning, positively affected memory. Furthermore, it was analyzed whether exercise-induced changes in the brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) were related to memory enhancement after a single bout of physical exercise. Fifty healthy participants (20–40 years) were randomly assigned to either a cycling group (BIKE) or a stretching and toning group (STRETCH). Participants performed an implicit vocabulary learning task which was immediately followed by physical exercise. Memory for the learned vocabulary was tested 1–2 weeks later. To measure exercise-induced changes in serum neurotrophic factor levels, blood samples were collected at rest (baseline) and immediately after the exercise session. Results did not show a significant difference in memory between the BIKE group and the STRETCH group. However, in the BIKE group, a larger increase in BDNF and VEGF levels was observed than in the STRETCH group. Moreover, the increase in BDNF and memory performance tended to be positively related in the BIKE group. We speculate that the correlation between exercise-increased BDNF levels and memory in the cycling group may indicate an involvement of BDNF in mediating memory processes after acute cardiovascular exercise.

Walking and Daily Affect Among Sedentary Older Adults Measured Using the StepMATE App: Pilot Randomized Controlled Trial

BACKGROUND

Although fitness technology can track and encourage increases in physical activity, few smartphone apps are based on behavior change theories. Apps that do include behavioral components tend to be costly and often do not include strategies to help those who are unsure of how to increase their physical activity.

OBJECTIVE

The aim of this pilot study is to test the efficacy of a new app, StepMATE, for increasing daily walking in a sample of inactive adults and to examine daily relationships between walking and self-reported mood and energy.

METHODS

The participants were middle-aged and older adults aged ≥50 years (mean 61.64, SD 7.67 years). They were randomly assigned to receive either a basic, pedometer-like version of the app or a version with supports to help them determine where, when, and with whom to walk. Of the 96 participants randomized to 1 of 2 conditions, 87 (91%) completed pretest assessments and 81 (84%) successfully downloaded the app. Upon downloading the app, step data from the week prior were automatically recorded. The participants in both groups were asked to set a daily walking goal, which they could change at any point during the intervention. They were asked to use the app as much as possible over the next 4 weeks. Twice per day, pop-up notifications assessed mood and energy levels.

RESULTS

Although one group had access to additional app features, both groups used the app in a similar way, mainly using just the walk-tracking feature. Multilevel models revealed that both groups took significantly more steps during the 4-week study than during the week before downloading the app (γ=0.24; P<.001). During the study, the participants in both groups averaged 5248 steps per day compared with an average of 3753 steps per day during the baseline week. Contrary to predictions, there were no differences in step increases between the two conditions. Cognition significantly improved from pre- to posttest (γ=0.17; P=.02). Across conditions, on days in which the participants took more steps than average, they reported better mood and higher energy levels on the same day and better mood on the subsequent day. Daily associations among walking, mood, and energy were significant for women but not for men and were stronger for older participants (those aged ≥62 years) than for the younger participants.

CONCLUSIONS

Both groups increased their steps to a similar extent, suggesting that setting and monitoring daily walking goals was sufficient for an initial increase and maintenance of steps. Across conditions, walking had benefits for positive mood and energy levels, particularly for women and older participants. Further investigations should identify other motivating factors that could lead to greater and more sustained increases in physical activity.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03124537; https://clinicaltrials.gov/ct2/show/NCT03124537.

Acute and Chronic Exercise Effects on Human Memory: What We Know and Where to Go from Here

Although the acquisition, storage, and retrieval of memories was once thought to happen within a single memory system with multiple processes operating on it, it is now believed that memory is comprised of both distinct and interacting brain systems [...].

Can acute resistance exercise facilitate episodic memory encoding?

Research has shown benefits of physical exercise on memory performance when carried out before or after a memory task. The effects of concurrent physical exercise and particularly resistance exercise are still inconclusive. The current study investigates the influence of resistance exercise with two intensities (fast and slow squats) on performance in a wordlist learning task using a within-subject design. Sport students (N = 58, Mage = 23 years; 26 women) were trained in a mnemonic technique to encode word lists (method of loci). In each session they were asked to encode two lists, each consisting of 20 words. During encoding, participants either performed one squat per word (fast-squat-condition), one squat every second word (slow-squat-condition), or stayed seated (control-condition). Participants performed three sessions for each condition, in counterbalanced order. Heart rates differed significantly according to exercise intensity. Memory performances in the sitting condition were better, compared to the exercise conditions. Performance in sitting and the fast squat conditions improved similarly over time, while performance in the slow squat condition increased faster, and reached the level of the fast squat condition at the end of the study phase. We conclude that light to moderate resistance exercise while working on an episodic memory task may rather represent a dual-task situation (= two tasks that compete for attentional resources). Especially doing a squat every second word may represent an inhibition task that people have to get used to. Future studies should include biochemical markers of arousal and neuronal plasticity in addition to heart rate.

Evaluation of the transient hypofrontality theory in the context of exercise: A systematic review with meta-analysis

Accumulating research suggests that, as a result of reduced neural activity in the prefrontal cortex (PFC), higher-order cognitive function may be compromised while engaging in high-intensity acute exercise, with this phenomenon referred to as the transient hypofrontality effect. However, findings in this field remain unclear and lack a thorough synthesis of the evidence. Therefore, the purpose of this meta-analysis was to evaluate the effects of in-task acute exercise on cognitive function, and further, to examine whether this effect is moderated by the specific type of cognition (i.e., PFC-dependent vs. non-PFC-dependent). Studies were identified by electronic databases in accordance with the PRISMA guidelines. In total, 22 studies met our inclusion criteria and intercept only meta-regression models with robust variance estimation were used to calculate the weighted average effect sizes across studies. Acute exercise at all intensities did not influence cognitive function (β = -0.16, 95% CI = [-0.58, 0.27], p = .45) when exercise occurred during the cognitive task, and no significant moderation effects emerged. However, there was evidence that cognitive task type (PFC-dependent vs. non-PFC-dependent) moderated the effect of high-intensity acute exercise on a concomitant cognitive performance (β = -0.81, 95% CI = [-1.60, -0.02], p = .04). Specifically, our findings suggest that PFC-dependent cognition is impaired while engaging in an acute bout of high-intensity exercise, providing support for the transient hypofrontality theory. We discuss these findings in the context of reticular-activating and cognitive-energetic perspectives.

Examining the Role of Physical Activity on Word Learning in School-Aged Children

Purpose Previous studies show that there is increased brain activity after exercise, leading to improved word recall in adults. The aim of this study was to examine whether different types of exercise (i.e., aerobic vs. anaerobic) may also lead to improved performance during vocabulary learning in children. Method A total of 48 participants (24 in Experiment 1 and 24 in Experiment 2) between the ages of 6 and 12 years completed a word learning task. Training of words took place in a resting and in an exercise condition using a within-subject design. In the resting measure, children were taught names of novel objects and then colored for 3 min before being tested on their ability to recognize the words. In the exercise condition, the same steps were followed, but instead of coloring, children engaged in 3 min of either aerobic exercise (i.e., swimming in Experiment 1) or anaerobic exercise (i.e., a CrossFit-like workout in Experiment 2). Results In Experiment 1, accuracy of word recognition was significantly higher for words that were trained in the aerobic exercise compared to the resting condition. In Experiment 2, there was no significant difference in performance between the anaerobic exercise and resting conditions. Conclusions These findings suggest that previously identified benefits of exercise on language abilities in adults also extend to school-aged children. However, not all types of physical activity lead to this boost in performance, as only aerobic (but not anaerobic) exercise improved children's ability to acquire new word-object relations. Supplemental Material https://doi.org/10.23641/asha.14462187.

Mindfulness and Other Simple Neuroscience-Based Proposals to Promote the Learning Performance and Mental Health of Students during the COVID-19 Pandemic

The COVID-19 pandemic has had a negative impact on education. The restrictions imposed have undoubtedly led to impairment of the psychological well-being of both teachers and students, and of the way they experience interpersonal relationships. As reported previously in the literature, adverse effects such as loneliness, anxiety, and stress have resulted in a decrease in the cognitive performance of school and higher education students. Therefore, the objective of this work is to present a general overview of the reported adverse effects of the COVID-19 pandemic which may potentially influence the learning performance of students. Some neuroscientific findings related to memory and cognition, such as neuroplasticity and long-term potentiation, are also shown. We also discuss the positive effects of the practice of mindfulness, as well as other simple recommendations based on neuroscientific findings such as restful sleep, physical activity, and nutrition, which can act on memory and cognition. Finally, we propose some practical recommendations on how to achieve more effective student learning in the context of the pandemic. The aim of this review is to provide some assistance in this changing and uncertain situation in which we all find ourselves, and we hope that some of the information could serve as a starting point for hypotheses to be tested in educational research and their association with neuroscience.

Cognitive-Motor Dual Task Interference Effects on Declarative Memory: A Theory-Based Review

Bouts of exercise performed either prior to or immediately following study periods enhance encoding and learning. Empirical evidence supporting the benefits of interventions that simultaneously pair physical activity with material to be learned is not conclusive, however. A narrative, theory-based review of dual-task experiments evaluated studies in terms of arousal theories, attention theories, cognitive-energetic theories, and entrainment theories. The pattern of the results of these studies suggests that cognitive-motor interference can either impair or enhance memory of semantic information and the manner in which physical activity impacts working memory within executive processing appears to explain disparate outcomes. The integration and timing of physical movements in concert with the type of information to be encoded and remembered appears to be a critical requirement for learning. These observations have implications for the role of physical activity in education, rehabilitation, and gerontological settings.

Running During Encoding Improves Word Learning for Children

The learning of new information is an important task in everyday life, especially at a young age. Acute physical exercise can facilitate cognitive processes in multiple ways, and previous studies have shown that memory can profit from physical exercise before and during the encoding of vocabulary. The current study investigates the interplay of movement and vocabulary learning and also addresses lifespan differences in these effects. Participants were recruited in a recreational basketball club. Children (n = 24, M_age = 12.3 years; 13 girls), young adults (n = 30, M_age = 21.5 years; 17 women), and older adults (n = 24, M_age = 59.3 years; 9 women) learned 20 new pseudo-words, which corresponded to a German word. In a between-subjects design, encoding took place either while standing, while running, or while running and dribbling a basketball. Recall was assessed three times throughout the learning session and on the following day. In children, more words could be remembered in the running condition compared to the standing condition. There were no differences between conditions for the young and older adults. Age-dependent reasons for this pattern of results are discussed and embedded into the literature of physical exercise. Our result suggests that implementing learning activities into children’s physical education or exercise activities could be beneficial.

Does brain-derived neurotrophic factor mediate the effects of exercise on memory?

Objective: Brain-derived neurotrophic factor (BDNF) has been hypothesized as a potential mechanism through which exercise may subserve memory function. The present review specifically evaluates this hypothesis.Methods: Studies were identified using electronic databases, including PubMed, PsychInfo, Sports Discus and Google Scholar.Results: In total, 52 articles met the study criteria, and among these, 36 were conducted in an animal model and 16 among humans. Among the animal experiments, 100% of them demonstrated that chronic exercise improved memory function; 97% demonstrated an exercise-induced increase in BDNF; and among the eight evaluating BDNF as a mediator, 100% provided evidence that BDNF mediated the relationship between exercise and memory. The findings in the human studies were mixed. Among the human studies, 44% demonstrated that varying exercise protocols improved memory and increased BDNF levels, and among the studies evaluating BDNF as a mediator, 40% provided evidence that BDNF mediated the relationship between exercise and memory.Conclusion: In animal models, chronic exercise training robustly increases BDNF and improves memory performance, with reasonable evidence to also suggest that BDNF may mediate the exercise-memory interaction. These interrelationships, however, are less clear among humans. Future research among humans, in particular, is needed to evaluate the extent to which BDNF may mediate the relationship between exercise and memory.

BDNF and Cortisol integrative system - Plasticity vs. degeneration: Implications of the Val66Met polymorphism

BDNF is the neurotrophin mediating pro-neuronal survival and plasticity. Cortisol (COR), in turn, is engaged in the coordination of several processes in the brain homeostasis. Stress-responsive, both factors show an integrative role through their receptor's dynamics in neurophysiology. Furthermore, the Val66Met BDNF polymorphism may play a role in this mechanism.

AIM

to investigate BDNF-COR interaction in the human neurophysiology context.

METHODS

We collected all papers containing BDNF and COR parameters or showing COR analyses in genotyped individuals in a PubMed search - full description available on PROSPERO - CRD42016050206.

DISCUSSION

BDNF and COR perform distinct roles in the physiology of the brain whose systems are integrated by glucocorticoid receptors dynamics. The BDNF polymorphism appears to have an influence on individual COR responsivity to stress. BDNF and COR play complementary roles in the nervous system where COR is a regulator of positive/negative effects. Exercise positively regulates both factors, regardless of BDNF polymorphism.

Physical Activity and Brain Health

Physical activity (PA) has been central in the life of our species for most of its history, and thus shaped our physiology during evolution. However, only recently the health consequences of a sedentary lifestyle, and of highly energetic diets, are becoming clear. It has been also acknowledged that lifestyle and diet can induce epigenetic modifications which modify chromatin structure and gene expression, thus causing even heritable metabolic outcomes. Many studies have shown that PA can reverse at least some of the unwanted effects of sedentary lifestyle, and can also contribute in delaying brain aging and degenerative pathologies such as Alzheimer’s Disease, diabetes, and multiple sclerosis. Most importantly, PA improves cognitive processes and memory, has analgesic and antidepressant effects, and even induces a sense of wellbeing, giving strength to the ancient principle of “mens sana in corpore sano” (i.e., a sound mind in a sound body). In this review we will discuss the potential mechanisms underlying the effects of PA on brain health, focusing on hormones, neurotrophins, and neurotransmitters, the release of which is modulated by PA, as well as on the intra- and extra-cellular pathways that regulate the expression of some of the genes involved.

Auditory-motor coupling affects phonetic encoding

Recent studies have shown that moving in synchrony with auditory stimuli boosts attention allocation and verbal learning. Furthermore rhythmic tones are processed more efficiently than temporally random tones ('timing effect'), and this effect is increased when participants actively synchronize their motor performance with the rhythm of the tones, resulting in auditory-motor synchronization. Here, we investigated whether this applies also to sequences of linguistic stimuli (syllables). We compared temporally irregular syllable sequences with two temporally regular conditions where either the interval between syllable onsets (stimulus onset asynchrony, SOA) or the interval between the syllables' vowel onsets was kept constant. Entrainment to the stimulus presentation frequency (1 Hz) and event-related potentials were assessed in 24 adults who were instructed to detect pre-defined deviant syllables while they either pedaled or sat still on a stationary exercise bike. We found larger 1 Hz entrainment and P300 amplitudes for the SOA presentation during motor activity. Furthermore, the magnitude of the P300 component correlated with the motor variability in the SOA condition and 1 Hz entrainment, while in turn 1 Hz entrainment correlated with auditory-motor synchronization performance. These findings demonstrate that acute auditory-motor coupling facilitates phonetic encoding.

Acute high-intensity aerobic exercise affects brain-derived neurotrophic factor in mild cognitive impairment: a randomised controlled study

OBJECTIVE

To investigate the brain-derived neurotrophic factor (BDNF) and cognitive response to a short bout of high-intensity aerobic exercise in older adults with mild cognitive impairment (MCI).

METHODS

Participants were randomised to one of two testing schedules, completing either a standardised exercise test (group A) or a resting control condition (group B). Blood sampling and cognitive measures (visuospatial learning and memory, sustained attention and executive function) were collected at baseline (T1) and postintervention (T2). An additional measurement of study outcomes was collected after exercise (T3) in group B only.

RESULTS

64 participants (female 53.2%, mean age 70.5±6.3 years) with MCI were recruited. From T1 to T2, serum BDNF (sBDNF) concentration increased in group A (n=35) (median (Md) 4564.61±IQR 5737.23 pg/mL to Md 5173.27±5997.54 pg/mL) and decreased in group B (Md 4593.74±9558.29 pg/mL to Md 3974.66±3668.22 pg/mL) (between-group difference p=0.024, effect size r=0.3). The control group made fewer errors on the sustained attention task compared with the exercise group (p=0.025). Measures of visuospatial learning and memory or executive function did not change significantly between groups.

CONCLUSION

This study is the first to show that a short bout of high-intensity aerobic exercise increases peripheral sBDNF in a population with MCI. However, acute exercise did not improve cognitive performance.

Cognitive demand of eccentric versus concentric cycling and its effects on post-exercise attention and vigilance

PURPOSE

This study tested the hypotheses that eccentric cycling (ECC) would be more cognitively demanding than concentric cycling (CONC), and attention and vigilance would improve more after ECC than CONC.

METHODS

Thirty young adults performed CONC and two bouts of ECC (ECC1 and ECC2) for 20 min at a similar workload (227.5 ± 51.5 W) with 1-week apart. Cognitive load during exercise was assessed by the average error from the target torque over 1200 (60 rpm × 20 min) revolutions, choice reaction time (CRT), the NASA-task load index (NASA-TLX), and prefrontal cortex oxygenation and deoxygenation (HHb) by near-infrared spectroscopy. Attention and vigilance were assessed by a sustained attention to response task (SART) before, immediately, and at every 15 min for 60 min after exercise or sitting (control).

RESULTS

Heart rate was lower during ECC1 (115.5 ± 20.3 bpm) and ECC2 (116.7 ± 21.0 bpm) than CONC (156.9 ± 19.4 bpm). The torque error was greater for ECC1 (26.1 ± 9.0%) and ECC2 (19.4 ± 9.0%) than CONC (10.8 ± 3.7%). CRT (CONC: 602.8 ± 69.0, ECC1: 711.1 ± 113.0, ECC2: 693.6 ± 122.6 ms) and mental demand in NASA-TLX (46.8 ± 25.8, 80.0 ± 15.3, 60.3 ± 17.6) were greater for ECC1 and ECC2 than CONC. Decreases in HHb were greater for ECC1 (- 0.41 ± 0.37 µM) and ECC2 (- 0.40 ± 0.40 µM) than CONC (0.10 ± 0.40 µM) and control (- 0.21 ± 0.28 µM). Attention and vigilance decreased 2-8% after 20-min sitting, but improved 2-10% immediately after ECC2, and did not decline from the baseline for 30 min after ECC1 or 60 min after CONC and ECC2.

CONCLUSION

Cognitive load was greater during ECC than CONC, but post-exercise attention and vigilance changes were not largely different between ECC and CONC.

The Temporal Effects of Acute Exercise on Episodic Memory Function: Systematic Review with Meta-Analysis

Background: Accumulating research demonstrates that the timing of exercise plays an important role in influencing episodic memory. However, we have a limited understanding as to the factors that moderate this temporal effect. Thus, the purpose of this systematic review with meta-analysis was to evaluate the effects of study characteristics (e.g., exercise modality, intensity and duration of acute exercise) and participant attributes (e.g., age, sex) across each of the temporal periods of acute exercise on episodic memory (i.e., acute exercise occurring before memory encoding, and during memory encoding, early consolidation, and late consolidation). Methods: The following databases were used for our computerized searches: Embase/PubMed, Web of Science, Google Scholar, Sports Discus and PsychInfo. Studies were included if they: (1) Employed an experimental design with a comparison to a control group/visit, (2) included human participants, (3) evaluated exercise as the independent variable, (4) employed an acute bout of exercise (defined as a single bout of exercise), (5) evaluated episodic memory as the outcome variable (defined as the retrospective recall of information either in a spatial or temporal manner), and (6) provided sufficient data (e.g., mean, SD, and sample size) for a pooled effect size estimate. Results: In total, 25 articles met our inclusionary criteria and were meta-analyzed. Acute exercise occurring before memory encoding (d = 0.11, 95% CI: −0.01, 0.23, p = 0.08), during early memory consolidation (d = 0.47, 95% CI: 0.28, 0.67; p < 0.001) and during late memory consolidation (d = 1.05, 95% CI: 0.32, 1.78; p = 0.005) enhanced episodic memory function. Conversely, acute exercise occurring during memory encoding had a negative effect on episodic memory (d = −0.12, 95% CI: −0.22, −0.02; p = 0.02). Various study designs and participant characteristics moderated the temporal effects of acute exercise on episodic memory function. For example, vigorous-intensity acute exercise, and acute exercise among young adults, had greater effects when the acute bout of exercise occurred before memory encoding or during the early memory consolidation period. Conclusions: The timing of acute exercise plays an important role in the exercise-memory interaction. Various exercise- and participant-related characteristics moderate this temporal relationship.

An integrated model of acute exercise on memory function

Memory is a complex cognition that plays a critical role in daily functioning. This review discusses the dynamic effects of acute exercise on memory function, via a hypothesized exercise-memory interaction model, taking into consideration multiple memory systems and exercise parameters.

A Narrative Review of School-Based Physical Activity for Enhancing Cognition and Learning: The Importance of Relevancy and Integration

Engaging in regular physical activity can have substantial cognitive and academic benefits for children, and is generally promoted for its beneficial effects on children's physical and mental health. Although embodied cognition research has convincingly shown the integral relationship of the human body and mind, in schools physical activity and cognitive activity are typically treated as unrelated processes. Consequently, most physical activities used are neither sufficiently relevant for nor fully integrated into the learning tasks. In reviewing the literature regarding the integration of physical activity into education to promote cognition and learning, two main lines of research emerged: exercise and cognition research vs. embodied cognition research. In this narrative review, we describe these two separately evolved schools of thought, highlighting their differences and commonalities. In categorising the existing studies on a 2 × 2 matrix, concerning the two main categories of relevance for and integration into the learning task, it becomes clear where the different foci lie, and how both lines of research could profit from learning from each other. Finally, a new instructional model that integrates task-relevant physical activities into the cognitive/learning task is proposed to inform both further research and educational practice.

Temporal Effects of Acute Walking Exercise on Learning and Memory Function

PURPOSE

To evaluate the temporal effects of acute exercise on episodic memory.

DESIGN

A quasi-experimental study.

SAMPLE

Eighty-eight college students (N = 22 per group).

MEASURES

Four experimental groups were evaluated, including a control group, exercising prior to memory encoding, exercising during encoding, and exercising during memory consolidation. The exercise stimulus consisted of a 15-minute moderate-intensity walk on a treadmill. Participants completed the Rey Auditory Verbal Learning Test (RAVLT) to assess learning and memory. Prospective memory was assessed via a Red Pen Task. Long-term memory (recognition and attribution) of the RAVLT was assessed 20 minutes and 24 hours after exercise.

ANALYSIS

Repeated-measures analysis of variance (ANOVA) assessed the performance of RAVLT scores of trials 1 to 5 across groups. One-way ANOVA assessed the performance of individual trials across groups, whereas χ² assessed the performance of the Red Pen Task across groups.

RESULTS

Regarding learning, the interaction of groups × trial was marginally statistically significant ( F_12,332 = 1.773, P = .05), indicating that the group which exercised before encoding did better than the group that exercised during encoding and consolidation. For both 24-hour recognition and attribution performance, the group that exercised before memory encoding performed significantly better than the group that exercised during consolidation ( P = .05 recognition, P = .006 attribution).

DISCUSSION

Engaging in a 15-minute bout of moderate-intensity walking before a learning task was effective in influencing long-term episodic memory.

Aerobic Exercise as an Adjuvant to Aphasia Therapy: Theory, Preliminary Findings, and Future Directions

PURPOSE

This study investigated whether participation in aerobic exercise enhances the effects of aphasia therapy, and the degree to which basal serum brain-derived neurotropic factor (BDNF) concentrations fluctuate after the beginning of aerobic exercise or stretching activities in individuals with poststroke aphasia.

METHODS

The study used a single-subject, multiple-baseline design. Seven individuals with chronic poststroke aphasia participated in 2 Blocks of aphasia therapy: aphasia therapy alone (Block 1), followed by aphasia therapy with the addition of aerobic activity via bicycle ergometer (n = 5) or stretching (n = 2) (Block 2). Serum BDNF concentrations from blood draws were analyzed in 4 participants who exercised and in 1 participant who stretched.

FINDINGS

Three of the five exercise participants demonstrated larger Tau-U effects when aphasia therapy was paired with aerobic exercise, whereas 1 of the 2 stretching participants demonstrated a larger effect size when aphasia therapy was paired with stretching. Group-level comparisons revealed a greater overall increase in effect size in the aerobic exercise group, as indicated by differences in Tau-U weighted means. BDNF data showed that all 4 exercise participants demonstrated a decrease in BDNF concentrations during the first 6 weeks of exercise and an increase in BDNF levels near or at baseline during the last 6 weeks of exercise. The stretching participant did not show the same pattern.

IMPLICATIONS

Additional research is needed to understand the mechanism of effect and to identify the factors that mediate response to exercise interventions, specifically the optimal dose of exercise and timing of language intervention with exercise. ClinicalTrials.gov identifier: NCT01113879.

Randomized controlled trial evaluating the temporal effects of high-intensity exercise on learning, short-term and long-term memory, and prospective memory

The broader purpose of this study was to examine the temporal effects of high-intensity exercise on learning, short-term and long-term retrospective memory and prospective memory. Among a sample of 88 young adult participants, 22 were randomized into one of four different groups: exercise before learning, control group, exercise during learning, and exercise after learning. The retrospective assessments (learning, short-term and long-term memory) were assessed using the Rey Auditory Verbal Learning Test. Long-term memory including a 20-min and 24-hr follow-up assessment. Prospective memory was assessed using a time-based procedure by having participants contact (via phone) the researchers at a follow-up time period. The exercise stimulus included a 15-min bout of progressive maximal exertion treadmill exercise. High-intensity exercise prior to memory encoding (vs. exercise during memory encoding or consolidation) was effective in enhancing long-term memory (for both 20-min and 24-h follow-up assessments). We did not observe a differential temporal effect of high-intensity exercise on short-term memory (immediate post-memory encoding), learning or prospective memory. The timing of high-intensity exercise may play an important role in facilitating long-term memory.

The brain during free movement - What can we learn from the animal model

Animals, just like humans, can freely move. They do so for various important reasons, such as finding food and escaping predators. Observing these behaviors can inform us about the underlying cognitive processes. In addition, while humans can convey complicated information easily through speaking, animals need to move their bodies to communicate. This has prompted many creative solutions by animal neuroscientists to enable studying the brain during movement. In this review, we first summarize how animal researchers record from the brain while an animal is moving, by describing the most common neural recording techniques in animals and how they were adapted to record during movement. We further discuss the challenge of controlling or monitoring sensory input during free movement. However, not only is free movement a necessity to reflect the outcome of certain internal cognitive processes in animals, it is also a fascinating field of research since certain crucial behavioral patterns can only be observed and studied during free movement. Therefore, in a second part of the review, we focus on some key findings in animal research that specifically address the interaction between free movement and brain activity. First, focusing on walking as a fundamental form of free movement, we discuss how important such intentional movements are for understanding processes as diverse as spatial navigation, active sensing, and complex motor planning. Second, we propose the idea of regarding free movement as the expression of a behavioral state. This view can help to understand the general influence of movement on brain function. Together, the technological advancements towards recording from the brain during movement, and the scientific questions asked about the brain engaged in movement, make animal research highly valuable to research into the human "moving brain".

Aerobic Exercise During Encoding Impairs Hippocampus-Dependent Memory

We investigated how aerobic exercise during encoding affects hippocampus-dependent memory through a source memory task that assessed hippocampus-independent familiarity and hippocampus-dependent recollection processes. Using a within-participants design, young adult participants performed a memory-encoding task while performing a cycling exercise or being seated. The subsequent retrieval phase was conducted while sitting on a chair. We assessed behavioral and event-related brain potential measures of familiarity and recollection processes during the retrieval phase. Results indicated that source accuracy was lower for encoding with exercise than for encoding in the resting condition. Event-related brain potential measures indicated that the parietal old/new effect, which has been linked to recollection processing, was observed in the exercise condition, whereas it was absent in the rest condition, which is indicative of exercise-induced hippocampal activation. These findings suggest that aerobic exercise during encoding impairs hippocampus-dependent memory, which may be attributed to inefficient source encoding during aerobic exercise.

CRH promotes human colon cancer cell proliferation via IL-6/JAK2/STAT3 signaling pathway and VEGF-induced tumor angiogenesis

Corticotrophin-releasing hormone (CRH) has been demonstrated to participate in various diseases. Our previous study showed that its receptor CRHR1 mediated the development of colitis-associated cancer in mouse model. However, the detailed mechanisms remain unclear. In this study, we explored the oncogenetic role of CRH/CRHR1 signaling in colon cancer cells. Cell proliferation and colony formation assays revealed that CRH contributed to cell proliferation. Moreover, tube formation assay showed that CRH-treated colon cancer cell supernatant significantly promoted tube formation of human umbilical vein endothelial cells (HUVECs). And these effects could be reversed by the CRHR1 specific antagonist Antalarmin. Further investigation showed that CRH significantly upregulated the expressions of interlukin-6 (IL-6) and vascular endothelial growth factor (VEGF) through activating nuclear factor-kappa B (NF-κB). The CRH-induced IL-6 promoted phosphorylation of janus kinase 2 (JAK2) and signal transducers and activators of transcription 3 (STAT3). STAT3 inhibition by Stattic significantly inhibited the CRH-induced cell proliferation. In addition, silence of VEGF resulted in declined tube formation induced by CRH. Taken together, CRH/CRHR1 signaling promoted human colon cancer cell proliferation via NF-κB/IL-6/JAK2/STAT3 signaling pathway and tumor angiogenesis via NF-κB/VEGF signaling pathway. Our results provide evidence to support a critical role for the CRH/CRHR1 signaling in colon cancer progression and suggest its potential utility as a new therapeutic target for colon cancer.

Effects of Isometric Hand-Grip Muscle Contraction on Young Adults' Free Recall and Recognition Memory

PURPOSE

The purpose of this study was to determine if physical arousal produced by isometric hand-dynamometer contraction performed during word-list learning affects young adults' free recall or recognition memory.

METHOD

Twenty-four young adults (12 female; M_age = 22 years) were presented with 4 20-item word lists. Moderate arousal was induced in 12 adults by an initial 30-s maximal hand-dynamometer squeeze with force productions of 50% maximum; low arousal was induced in 12 adults by an initial 1-s maximal dynamometer squeeze with force production of 10% maximum during learning. Memory performances following dual-task conditions experienced during the encoding, consolidation, and recall phases of learning were compared to a single-task control condition during which words were learned in the absence of isometric exercise.

RESULTS

Planned contrasts revealed that arousal coinciding with word encoding led to significantly poorer immediate recall, F(1, 23) = 10.13, p < .05, [Formula: see text] = .31, delayed free recall, F(1, 23) = 15.81, p < .05, [Formula: see text] = .41, and recognition memory, F(1, 23) = 6.07, p < .05, [Formula: see text] = .21, compared with when there was no arousal. Neither arousal condition facilitated participants' memory performance.

CONCLUSION

The reduction in long-term memory performance specific to the encoding phase of learning is explained in terms of the dual-task attentional demands placed on participants.

The Effects of Acute Physical Exercise on Memory, Peripheral BDNF, and Cortisol in Young Adults

In animals, physical activity has been shown to induce functional and structural changes especially in the hippocampus and to improve memory, probably by upregulating the release of neurotrophic factors. In humans, results on the effect of acute exercise on memory are inconsistent so far. Therefore, the aim of the present study was to assess the effects of a single bout of physical exercise on memory consolidation and the underlying neuroendocrinological mechanisms in young adults. Participants encoded a list of German-Polish vocabulary before exercising for 30 minutes with either high intensity or low intensity or before a relaxing phase. Retention of the vocabulary was assessed 20 minutes after the intervention as well as 24 hours later. Serum BDNF and salivary cortisol were measured at baseline, after learning, and after the intervention. The high-intensity exercise group showed an increase in BDNF and cortisol after exercising compared to baseline. Exercise after learning did not enhance the absolute number of recalled words. Participants of the high-intensity exercise group, however, forgot less vocabulary than the relaxing group 24 hours after learning. There was no robust relationship between memory scores and the increase in BDNF and cortisol, respectively, suggesting that further parameters have to be taken into account to explain the effects of exercise on memory in humans.