Investigating the acute effect of an aerobic dance exercise program on neuro-cognitive function in the elderly

ObjectiveThe present study investigated the types of aerobic dance programs that positively impact cognition, such as executive function, in elderly people.DesignRandomized controlled trial.MethodThe study compared the effects of acute aerobic dance exercise on cognitive performance using two 40-min aerobic dance programs. Thirty-four elderly participants, aged 65–75 years, were randomly assigned into either free (N = 17) or combination (N = 17) style workout groups. The free style (FR) workout consisted of several patterns of movement, while the combination style (CB) workout consisted of similar patterns of movement to FR, but the patterns were joined to form a long choreographic routine. Both dance programs were controlled to be the same in exercise intensity, approximately 40% heart rate reserve. Reaction time and correct rates were measured using a task-switching reaction time test to evaluate executive cognitive performance immediately before and after the 40-min dance exercise.ResultsA two-way (dance program × pre-post dance exercise) repeated-measures analysis of variance for switch reaction time increase (switch cost) demonstrated a significant interaction (p = .006), showing that the switch cost in the CB group became smaller after the dance exercise than before (p = .009).ConclusionThe results suggest that the executive cognitive network was facilitated in a CB dance workout that has a dual-task nature and induces movement (task) interference with unexpected movement changes.     

A dual identity-electronic contact (DIEC) experiment promoting short- and long-term intergroup harmony

Existing intergroup harmony programs have been short in length with little long-term evaluation of their true effectiveness. This experiment addresses this limitation through the development and evaluation of a new intergroup harmony program that integrates dual identity and contact tenets. At Time 1, 116 Australian Muslim and 104 Australian Christian first-year high school students attending religiously segregated schools completed pre-test measures of intergroup bias, intergroup anxiety, prejudice, and outgroup knowledge. Eight months later, in the next year of school, these students were allocated to either the nine-week dual identity-electronic or E-contact (DIEC) program that involved Muslim and Christians interacting via a synchronous internet chat tool, or the control condition where they completed the program within their religious groups with no recategorization. All participants completed the same pre-test measures at two weeks (Time 2) and 6-months (Time 3) post-program. At Time 2, for students in the DIEC condition, intergroup bias and intergroup anxiety decreased significantly, and outgroup knowledge increased significantly, compared to the control condition. In the case of intergroup bias, the decrease was maintained at Time 3. Moderation effects of ingroup identification and outgroup friendship, and mediation effects of intergroup anxiety were also found. These encouraging findings highlight that carefully designed E-contact programs can successfully promote intergroup harmony in both the short- and long-term.     

Relationship between loudness tolerance and the acceptance of background noise for young adults with normal hearing

This study investigated the relationship between listener loudness tolerance and listener acceptable noise level (ANL). Twenty-five normal hearing adults completed loudness tolerance and acceptable noise level measures. Loudness tolerance was measured using a scaling technique. The acceptable noise levels were calculated from a procedure designed to quantify a listener's willingness to accept background noise while listening to speech. Pearson correlation confirmed that loudness tolerance and acceptable noise levels are not related.     

The experience of force: the role of haptic experience of forces in visual perception of object motion and interactions, mental simulation, and motion-related judgments

Forces are experienced in actions on objects. The mechanoreceptor system is stimulated by proximal forces in interactions with objects, and experiences of force occur in a context of information yielded by other sensory modalities, principally vision. These experiences are registered and stored as episodic traces in the brain. These stored representations are involved in generating visual impressions of forces and causality in object motion and interactions. Kinematic information provided by vision is matched to kinematic features of stored representations, and the information about forces and causality in those representations then forms part of the perceptual interpretation. I apply this account to the perception of interactions between objects and to motions of objects that do not have perceived external causes, in which motion tends to be perceptually interpreted as biological or internally caused. I also apply it to internal simulations of events involving mental imagery, such as mental rotation, trajectory extrapolation and judgment, visual memory for the location of moving objects, and the learning of perceptual judgments and motor skills. Simulations support more accurate judgments when they represent the underlying dynamics of the event simulated. Mechanoreception gives us whatever limited ability we have to perceive interactions and object motions in terms of forces and resistances; it supports our practical interventions on objects by enabling us to generate simulations that are guided by inferences about forces and resistances, and it helps us learn novel, visually based judgments about object behavior.     

The distribution of fixation durations during reading: effects of stimulus quality

Participants' eye movements were recorded as they read single sentences presented normally, presented entirely in faint text, or presented normally except for a single faint word. Fixations were longer when the entire sentence was faint than when the sentence was presented normally. In addition, fixations were much longer on a single faint word embedded in normal text, compared to when the entire sentence was faint. The primary aim of the study was to examine the influence of stimulus quality on the distribution of fixation durations. Ex-Gaussian fitting revealed that stimulus quality affected the mean of the Normal component, but in contrast to results from single-word tasks (Plourde & Besner, 1997), stimulus quality did not affect the exponential component, regardless of whether one or all words were faint. The results also contrast with the finding (Staub, White, Drieghe, Hollway, & Rayner, 2010) that the word frequency effect on fixation durations is an effect on both of the critical distributional parameters. These findings are argued to have implications for the interpretation of the role of stimulus quality in word recognition, and for models of eye movement control in reading.     

Neural activation underlying cognitive control in the context of neutral and affectively charged pictures in children

The neural correlates of cognitive control for typically developing 9-year-old children were examined using dense-array ERPs and estimates of cortical activation (LORETA) during a go/no-go task with two conditions: a neutral picture condition and an affectively charged picture condition. Activation was estimated for the entire cortex after which data were exported for four regions of interests (ROIs): ventrolateral prefrontal cortex (VLPFC), dorsal anterior cingulate cortex (dACC), dorsolateral prefrontal cortex (DLPFC), and orbitofrontal/ventromedial prefrontal cortex (OFC/VMPFC). Results revealed faster reaction times, greater N2 activation, and greater prefrontal activation for the affectively charged picture condition than the neutral picture condition. The findings are discussed in reference to the impact of affective stimuli on recruitment of specific brain regions involved in cognitive control.     

Accuracy in parameter estimation for ANCOVA and ANOVA contrasts: sample size planning via narrow confidence intervals

Contrasts of means are often of interest because they describe the effect size among multiple treatments. High-quality inference of population effect sizes can be achieved through narrow confidence intervals (CIs). Given the close relation between CI width and sample size, we propose two methods to plan the sample size for an ANCOVA or ANOVA study, so that a sufficiently narrow CI for the population (standardized or unstandardized) contrast of interest will be obtained. The standard method plans the sample size so that the expected CI width is sufficiently small. Since CI width is a random variable, the expected width being sufficiently small does not guarantee that the width obtained in a particular study will be sufficiently small. An extended procedure ensures with some specified, high degree of assurance (e.g., 90% of the time) that the CI observed in a particular study will be sufficiently narrow. We also discuss the rationale and usefulness of two different ways to standardize an ANCOVA contrast, and compare three types of standardized contrast in the ANCOVA/ANOVA context. All of the methods we propose have been implemented in the freely available MBESS package in R so that they can be easily applied by researchers.     

Dissociation of short-term forgetting from the passage of time

In many theories, forgetting is closely linked to the passage of time. In the present experiments, recall in a short-term memory task was less accurate when the retention interval included a difficult arithmetic addition task, compared with an easy task. In a novel condition, the interfering task was switched from hard to easy partway through the retention interval. Recall accuracy at long retention intervals recovered from the level consistent with the hard interfering task to a more accurate level consistent with an easy interfering task. Such recovery is not in agreement with theories that link forgetting to the passage of time, such as trace decay. The reversed forgetting functions are more consistent with an account in which different levels of nonspecific retroactive interference in the retention interval just before the time of retrieval influence different levels of performance accuracy. With the uncoupling of interference levels from time, forgetting is dissociated from the passage of time.     

Perceived competence: a common core for self-efficacy and self-concept?

This study uses Bandura's Multidimensional Scales of Perceived Self-Efficacy (MSPSE; Bandura, 1990) and Harter's Self-Perception Profile for Adolescents (SPPA; Harter, 1988) to examine the extent to which self-efficacy and competency-related elements of the self-concept are independent constructs. Factor analysis of data provided by 778 high school students revealed that when measured using domain-general measures such as the MSPSE and SPPA, self-efficacy and competency self-concept do not represent totally separate, distinct constructs. Overlap of dimensions occurs at both the first- and second-order levels of analysis. The practical and theoretical implications of these findings are discussed.