Beverley J. Hale

Acute, intermediate intensity exercise, and speed and accuracy in working memory tasks: A meta-analytical comparison of effects

The purpose of this study was to compare, using meta-analytic techniques, the effect of acute, intermediate intensity exercise on the speed and accuracy of performance of working memory tasks. It was hypothesized that acute, intermediate intensity exercise would have a significant beneficial effect on response time and that effect sizes for response time and accuracy data would differ significantly. Random-effects meta-analysis showed a significant, beneficial effect size for response time, g=-1.41 (p<0.001) but a significant detrimental effect size, g=0.40 (p<0.01), for accuracy. There was a significant difference between effect sizes (Z(diff)=3.85, p<0.001). It was concluded that acute, intermediate intensity exercise has a strong beneficial effect on speed of response in working memory tasks but a low to moderate, detrimental one on accuracy. There was no support for a speed-accuracy trade-off. It was argued that exercise-induced increases in brain concentrations of catecholamines result in faster processing but increases in neural noise may negatively affect accuracy.

Differential effects of differing intensities of acute exercise on speed and accuracy of cognition: A meta-analytical investigation

The primary purpose of this study was to examine, using meta-analytical techniques, the differential effects of differing intensities of acute exercise on speed and accuracy of cognition. Overall, exercise demonstrated a small, significant mean effect size (g=0.14, p<0.01) on cognition. Examination of the comparison between speed and accuracy dependent variables showed that speed accounted for most of the effect. For speed, moderate intensity exercise demonstrated a significantly larger mean effect size than those for low and high intensities. For speed of processing during moderate intensity exercise, central executive tasks showed a larger effect size than recall and alertness/attention tasks; and mean effect size for counterbalanced or randomized studies was significantly greater than for studies in which a pre-exercise followed by during or post-exercise protocol was used. There was no significant difference between mean effect sizes when testing took place post-exercise compared to during exercise for speed but accuracy studies demonstrated a significantly larger mean effect size post-exercise. It was concluded that increased arousal during moderate intensity exercise resulted in faster speed of processing. The very limited effect on accuracy may be due to the failure to choose tests which are complex enough to measure exercise-induced changes in accuracy of performance.

Beyond the Catecholamines Hypothesis for an Acute Exercise–Cognition Interaction: A Neurochemical Perspective

Abstract Research shows that moderate duration, moderate intensity, acute exercise generates increases in plasma catecholamines concentrations, which stimulate the vagal/nucleus tractus solitarii pathway. This induces the synthesis and release of catecholamines in the brain. Moderate increases in catecholamines concentrations facilitate performance of most cognitive tasks. Long duration, moderate intensity, and heavy exercise generate excessive concentrations of catecholamines, as well as resulting in increased concentrations of cortisol, which interact with catecholamines to inhibit working memory. However, heavy exercise has a beneficial effect on long-term memory due to activation of β-adrenoreceptors in the hippocampus and increased exercise-induced brain-derived neurotrophic factor (BDNF) levels, which aid neurogenesis and neuroplasticity. Heavy exercise also facilitates performance of autonomous tasks, probably due to activation of α1- and β-adrenoreceptors. With attention/perception tasks results are somewhat equivocal, although theoretically activation of α1- and β-adrenoreceptors should also aid the performance of these tasks.

Effect of incremental exercise on initiation and movement times in a choice response, whole body psychomotor task

Objectives: To examine how exercise at moderate and maximal intensities affects performance on a choice response time, whole body psychomotor task. Methods: Subjects (n  =  12) were tested on a three-choice response time task, after rest and after exercise at 70% and 100% maximum power output (W˙max). The dependent variables were time to begin forward momentum (initiation time) and time to complete the movement (movement time). Stride time for the first and second strides and number of strides to cover first 1.1 m were also measured. Blood lactate concentrations and heart rate were recorded before and after completion of each psychomotor test. The subjects subjectively assessed the amount of effort that they used to complete the task. Results: Repeated measures analysis of variance showed a significant effect for initiation (F2,22  =  11.47, p<0.001) and movement times (F2,22  = 14.61, p<0.001). Post hoc least significant difference (LSD) tests showed that initiation time after exercise at 70% W˙max was significantly faster than that in the other two conditions. Speed of initiation after rest was significantly quicker than that after exercise at W˙max. For movement time, LSD tests showed that time after maximal exercise was significantly slower than that in the other two conditions. Stride time for the second stride showed a significant effect (F2,22  =  6.20, p<0.01). LSD tests found that time after exercise at W˙max was significantly slower in the other two conditions. Stepwise multiple regression analyses found that the increment of change, from rest, of lactate concentrations could significantly predict the increment of change in initiation (R2  =  0.40) and movement (R2  =  0.50) times. Conclusions: Exercise affects a whole body task differently from purely cognitive tasks. Central factors are probably more important than peripheral factors.

Does acute exercise affect the performance of whole-body, psychomotor skills in an inverted-U fashion? A meta-analytic investigation

The primary purpose of this study was to examine, using meta-analytical measures, whether research into the performance of whole-body, psychomotor tasks following moderate and heavy exercise demonstrates an inverted-U effect. A secondary purpose was to compare the effects of acute exercise on tasks requiring static maintenance of posture versus dynamic, ballistic skills. Moderate intensity exercise was determined as being between 40% and 79% maximum power output (ẆMAX) or equivalent, while ≥80% ẆMAX was considered to be heavy. There was a significant difference (Zdiff=4.29, p=0.001, R(2)=0.42) between the mean effect size for moderate intensity exercise (g=0.15) and that for heavy exercise size (g=-0.86). These data suggest a catastrophe effect during heavy exercise. Mean effect size for static tasks (g=-1.24) was significantly different (Zdiff=3.24, p=0.001, R(2)=0.90) to those for dynamic/ballistic tasks (g=-0.30). The result for the static versus dynamic tasks moderating variables point to perception being more of an issue than peripheral fatigue for maintenance of static posture. The difference between this result and those found in meta-analyses examining the effects of acute exercise on cognition shows that, when perception and action are combined, the complexity of the interaction induces different effects to when cognition is detached from motor performance.

Effect of acute hypoxia on cognition: A systematic review and meta-regression analysis

HighlightsHypoxia has a negative effect on cognition.Effect on central executive and non‐executive tasks did not differ significantly.Low (<60 mmHg) arterial partial pressure of oxygen predicts poor cognition.Hypobaric versus normobaric hypoxic conditions was not a significant moderator. ABSTRACT A systematic meta‐regression analysis of the effects of acute hypoxia on the performance of central executive and non‐executive tasks, and the effects of the moderating variables, arterial partial pressure of oxygen (PaO2) and hypobaric versus normobaric hypoxia, was undertaken. Studies were included if they were performed on healthy humans; within‐subject design was used; data were reported giving the PaO2 or that allowed the PaO2 to be estimated (e.g. arterial oxygen saturation and/or altitude); and the duration of being in a hypoxic state prior to cognitive testing was ≤6 days. Twenty‐two experiments met the criteria for inclusion and demonstrated a moderate, negative mean effect size (g = −0.49, 95% CI −0.64 to −0.34, p < 0.001). There were no significant differences between central executive and non‐executive, perception/attention and short‐term memory, tasks. Low (35–60 mmHg) PaO2 was the key predictor of cognitive performance (R2 = 0.45, p < 0.001) and this was independent of whether the exposure was in hypobaric hypoxic or normobaric hypoxic conditions.

Do you mind if I vape? Immediate effects of electronic cigarettes on perfusion in buccal mucosal tissue - a pilot study

The association between smoking and postoperative complications is compounded in patients who have oral and maxillofacial operations by an additional local effect, and patients often continue to smoke after operation despite advice to stop. Recent studies have suggested that nicotine may reduce inflammation and improve angiogenesis, so topical application may be beneficial for smokers. The electronic cigarette is increasing in popularity and more patients ask whether they can vape after operation. We investigated the effect of electronic cigarettes (of which half contained nicotine and half did not) on blood flow in the buccal mucosa in 10 volunteers immediately after vaping. Smokers were excluded as this was considered an additional variable in a small pilot study and our Trust has a no-smoking policy. After vaping for 5 minutes, capillary blood flow was measured in the buccal mucosa at 5-minute intervals using a laser Doppler probe, and the results were expressed as arbitrary perfusion units. There was a wide variation in results and a small but significant rise (p=0.008) as a result of nicotine vaping, but these fell to the same levels as before within 30 minutes. Electronic cigarettes may have an effect on blood flow to the oral mucosa, although further studies are needed to show whether they improve healing time after operation. Additional work is also needed to compare them with cigarettes.

Evaluation of How the Blended Use of a Virtual Learning Environment (VLE) Can Impact on Learning and Teaching in a Specific Module

Abstract This paper explores how the blended use of a virtual learning environment (VLE) can impact on student learning in a specific module within a small university in the UK. Students studying a module about crisis situations faced by children in different parts of the world were asked to contribute to online forums as part of their learning. Forty-seven students participated in the study. Student questionnaires, Moodle reports and student assessment grades were analysed to explore the benefits of online forums. In line with previous research, online forums were found to be popular with students and multiple perceived benefits were identified, such as flexibility, greater sense of community and enhanced higher learning skills. Analysis of student assessment grades suggests that online forums may also enhance student performance. However, a larger scale longitudinal study is necessary to determine this more clearly. Overall, the findings highlight the importance of viewing VLEs as a communication, collaboration and knowledge focused medium with the potential to enhance higher learning skills through the use of interactive online activities such as forums.

Salivary pooling: is it specific to particular regions in oral submucous fibrosis?

Despite extensive research, the pathophysiology of oral submucous fibrosis (OSMF), a premalignant condition that primarily affects the mucosa, is still unclear, although the chewing of areca nut is known to be the primary cause. While a clear association exists between areca nut and OSMF, very little has been published on the reason for its sporadic incidence in the mouth. Many authors have suggested the site where quid is habitually placed, but this fails to explain multiple sites in those who chew on one side. We hypothesised that the pattern of salivary pooling might affect the distribution of OSMF by carrying the chemicals responsible for mucosal damage. In our study of 174 patients, we evaluated the sites where quid was habitually placed and the areas of salivary pooling, and their association with the incidence of OSMF. Most chewers (136/174, 78%) placed the quid in the buccal vestibule, although other sites were also used including the vestibule of the lip, tongue, and floor of the mouth. The standardised residuals suggested significant associations (p<0.001) between salivary pooling and OSMF, and indicated that salivary pooling affects the mucosal surfaces where it occurs. Our results show that the quid is not the only cause of OSMF. Salivary pooling also has an important role and provides a possible mechanism for the sporadic incidence of the condition. To our knowledge this is the first study to evaluate salivary pooling as a contributory factor in OSMF, and it may help to explain the pattern of distribution. Further work is needed in this area to understand the association more fully.

Does the great auricular nerve predict the size of the main trunk of the facial nerve? A clinical and cadaveric study.

There seems to be only individual clinical experience and some anecdotal evidence about a relation between the width of the great auricular nerve (GAN) and the size of the main trunk of the facial nerve during parotidectomy. To our knowledge no anatomical studies have been published. In this cadaveric and clinical study we measured the widest point of the GAN as it crosses the sternomastoid muscle before it divides, and the main trunk of the facial nerve before it bifurcates. Measurements were obtained from 16 patients who required formal superficial parotidectomies with identification of the facial nerve, and from 21 cadavers (16 formalin-fixed and 5 fresh frozen) where both sides were dissected. We recorded the results and the side of dissection. The mean (SD) width of the GAN and facial nerve from all the dissections was 2.75 (0.53)mm and 2.83 (0.54)mm, respectively. There was a strong correlation between the width of the nerves from both sides (left: r=0.934, p<0.001; right: r=0.940, p<0.001). The nerves did not differ significantly in size in patients or cadavers (GAN: right, p=0.873; left, p=0.486; facial nerve: right, p=0.931; left, p=0.691). We have found that the GAN accurately predicts the width of the main trunk of the facial nerve. This is particularly useful surgically as a narrow GAN can alert the surgeon to expect a small facial nerve.