Distinguishing multi-voxel patterns and mean activation: Why, how, and what does it tell us?

The introduction of multi-voxel pattern analysis (MVPA) to the functional magnetic resonance imaging (fMRI) community has brought a deeper appreciation for the diverse forms of information that can be present within fMRI activity. The conclusions drawn from MVPA investigations are frequently influenced by both the ability to decode information from multi-voxel patterns and mean activation levels. In practice, MVPA studies vary widely in why and how they test for differing overall response levels. In this article, I examine the place of univariate information in MVPA investigations. I first discuss the variety of interpretations given to finding univariate response differences. I go on to discuss some of the analysis approaches used to investigate and compare univariate and multivariate sources of information, which can illuminate their respective contributions. It will be important for the MVPA and general fMRI community to continue to discuss and debate these important issues.     

Incentivizing physical activity using token reinforcement with preschool children

We combined several single‐subject designs to assess the effects of contingent and noncontingent token reinforcement on moderate‐to‐vigorous physical activity (MVPA) exhibited by 4 preschool‐aged children. Higher overall levels and longer bouts of MVPA reliably occurred when tokens were delivered contingent on MVPA for 3 of the 4 children when compared to baseline (no token) and for 2 of the 4 children when compared to noncontingent‐token conditions. The present study demonstrated that the delivery of tokens contingent on MVPA can increase and maintain MVPA exhibited by preschool‐aged children, resulting in more MVPA than in baseline conditions and conditions in which tokens are awarded without respect to MVPA. These results demonstrate that token economies can be used to increase MVPA and they add to the evidence base supporting the use of token economies to address a range of behavior problems.     

Beyond mind-reading: multi-voxel pattern analysis of fMRI data

A key challenge for cognitive neuroscience is determining how mental representations map onto patterns of neural activity. Recently, researchers have started to address this question by applying sophisticated pattern-classification algorithms to distributed (multi-voxel) patterns of functional MRI data, with the goal of decoding the information that is represented in the subject's brain at a particular point in time. This multi-voxel pattern analysis (MVPA) approach has led to several impressive feats of mind reading. More importantly, MVPA methods constitute a useful new tool for advancing our understanding of neural information processing. We review how researchers are using MVPA methods to characterize neural coding and information processing in domains ranging from visual perception to memory search.     

Belief-level markers of physical activity among young adult couples: Comparisons across couples without children and new parents

The health benefits of regular moderate–vigorous intensity physical activity (MVPA) are well established, yet young adults, particularly parents, often show declines in MVPA and may represent a critical population for intervention. Theory-based correlates used to guide future interventions are scant in this population. The purpose of this study was to examine theory of planned behaviour (TPB) belief-level constructs as correlates of directly assessed MVPA across cohorts of couples without children and with their first child over the initial 12?months. Participants were 238 adults (102 not expecting a child, 136 expecting first child) who completed baseline demographics, belief measures of the TPB and seven-day accelerometry, followed by assessments at 6 and 12 months. Results showed select medium-sized belief-PA correlations with sex and cohort interactions. Overall, women had larger affect-based behavioural belief associations with MVPA than men (e.g. PA relieves stress), and among new parents, mothers showed larger associations with control over MVPA than fathers. Mothers also had larger associations between control beliefs and MVPA compared to women without children (e.g. domestic duties, bad weather). Extremely high means and low variability on the behavioural beliefs show limited room for possible changes in intervention while control beliefs had low means suggesting room for change. Interventions targeting control among new mothers may be paramount for increasing MVPA, yet the TPB yielded less insight into the targets for promoting MVPA among young men.     

Momentary affective response to bouts of moderate-to-vigorous physical activity predicts changes in physical activity and sedentary behavior during behavioral weight loss

BackgroundAffective responses are posited to be key predictors of the uptake and maintenance of health behaviors. However, few studies have examined how individuals’ affective response to physical activity, as well as the degree to which their affect response changes, may predict changes in physical activity and sedentary time during behavioral weight loss treatment.PurposeThe current study examined how baseline momentary affective response (i.e., stress and anxiety) to moderate-to-vigorous physical activity (MVPA) and the degree of pre--post intervention change in this response predicted change in daily sedentary, light, and MVPA time during a three-month internet-based weight loss program.MethodsWomen with overweight/obesity (final N = 37) completed 14-day ecological momentary assessment (EMA) protocols with objective measurement of physical activity (i.e., bout-related MVPA time) before and after the intervention.ResultsWomen who had more reinforcing responses to MVPA (i.e., greater reductions in anxiety and stress response following MVPA bouts) at baseline had greater increases in overall MVPA at the end of the intervention. Those who had greater anxiety reductions after MVPA bouts at baseline also evidenced less sedentary time at the end of the intervention. Changes in affective responses across the intervention were not related to changes in physical activity levels.ConclusionsFindings suggest initial levels of affective reinforcement from MVPA bouts predict future change in MVPA and sedentary time during behavioral weight loss. Future work is needed to examine the utility of more precisely targeting affective responses to physical activity to optimize intervention approaches.     

利用脑成像多体素模式分析解码认知的神经表征:原理和应用

多体素模式分析(multi-voxel pattern analysis,MVPA)是一种基于机器学习理论发展出来的新的功能磁共振数据分析技术。MVPA技术通过训练分类器,对由不同认知状态引起的多体素信号模式进行分类。与传统的基于单个体素的分析方法相比,该技术可更敏感地检测脑对认知状态的表征,并使得从神经信号解码认知状态成为可能。文章介绍MVPA技术的基本原理、分析步骤以及可以用MVPA来解决的科学问题,并对应用中可能面临的问题提供了参考建议。     

Personality,motivational, and social cognition predictors of leisure-time physical activity

ObjectiveThe purpose of the present study was to investigate associations between personality traits of extraversion and neuroticism, autonomous motivation, and the Theory of Planned Behavior (TPB) constructs and leisure-time physical activity. The study examined whether autonomous motivation and the TPB constructs mediate the association between personality traits and physical activity, and whether personality traits moderate the relationship of autonomous motivation and the TPB constructs with physical activity.MethodsMiddle-aged women (N = 441) completed self-report measures of personality traits, autonomous motivation, attitudes, subjective norms, perceived behavioral control (PBC) and intention. Moderate-to-vigorous leisure-time physical activity (MVPA) was measured using accelerometers approximately seven weeks later. Participants’ past accelerometer-based MVPA was available from four years earlier.ResultsOnly autonomous motivation and past MVPA directly predicted MVPA. Neuroticism and past MVPA were indirectly related with MVPA through autonomous motivation. No support for a moderator role of personality traits was found.ConclusionsCurrent data suggest that autonomous motivation and past experience are prominent determinants of accelerometer-based leisure-time MVPA, but not beliefs and intentions.     

Adult attention and interaction can increase moderate‐to‐vigorous physical activity in young children

Evidence suggests that physical inactivity is prevalent among young children. To combat this, one recommendation for caregivers is to become actively involved in their child's physical activities. However, this general recommendation does not specify how or when a parent should become involved. The purpose of the current study was to conduct a functional analysis to identify a social consequence that would increase the moderate‐to‐vigorous physical activity (MVPA) exhibited by preschool‐aged children, and then to compare the effects of that social consequence when it was provided contingent on MVPA and when provided independent of MVPA. The results of the functional analyses indicated that 3 of 7 children were most active when attention or interactive play was provided contingent on MVPA. Results of the intervention analysis suggested that caregivers of young children should provide attention or interactive play contingent on MVPA when those consequences are identified as reinforcers in a functional analysis.     

Child perceived motor competence as a moderator between physical activity parenting and child objectively measured physical activity

This longitudinal study aimed to examine how physical activity parenting (PAP) directly predicted objectively measured children’s moderate-to-vigorous physical activity (MVPA) and sedentariness over a three-year transitional period from early to middle childhood, and second, whether the children’s perception of motor competence (PMC) mediated or moderated the influence of PAP to children’s MVPA or sedentariness. At time 1 (T1), PAP and children’s (N = 396, mean age 5.80, SD 1.04) PA were assessed by parental questionnaire. Three years later, at time 2 (T2), children’s (N = 396, mean age 8.80, SD 1.04) PMC was measured by a validated pictorial scale, and MVPA and sedentariness were measured by accelerometers. All the analyses were conducted using the Mplus statistical package (Version 8.4). The models were adjusted for the following covariates: children’s PA (T1), gender (T1), age (T1), mean accelerometer measurement in hours per day (T2), and parents’ education level (T1). Results showed that PAP at T1 did not significantly predict level of MVPA or sedentary time at T2 and, therefore, PMC did not mediate the PAP-children’s MVPA or sedentary time relationship either. However, PMC significantly moderated the relationship between PAP and MVPA but not between PAP and sedentary time. The results suggested that parental support positively predicts children’s MVPA among children with low PMC but not among children with high PMC. This unique finding proposes that family-based PA interventions could benefit from screening of children with low PMC and provision of PA counselling to their parents.     

From enjoyment to physical activity or from physical activity to enjoyment? Longitudinal associations in parent–child dyads

Abstract

Background: This longitudinal dyadic study used cross-lagged analyses to examine reciprocal patterns of associations between physical activity (PA) enjoyment and moderate-to-vigorous PA (MVPA) among children and their parents.

Methods: At Time 1 (T1) 879 parent–child dyads provided their data. The follow-up (Time 2, T2) took place 7–8-months later. MVPA and PA enjoyment scales were filled out separately by parents and children at T1 and T2.

Findings: Child PA enjoyment (T1) predicted a higher level of child MVPA (T2), parental PA enjoyment (T1) explained a higher level of parental MVPA (T2), and parental MVPA (T1) predicted a higher level of parental PA enjoyment (T2). Furthermore, child PA enjoyment (T1) predicted a higher level of parental PA enjoyment (T2).

Conclusions: Child PA enjoyment was the key variable predicting child and parental outcomes. In particular, it explained child MVPA, but also PA enjoyment among parents.     

Parents’ Social Status and Children’s Daily Physical Activity: The Role of Familial Socialization and Support

Physical activity is a health relevant factor, particularly in affluent societies where overweight and obesity are increasingly prevalent, even among children. Understanding the development of physical activity patterns in childhood is thus an important issue for health promotion. Following socialization theory, this study describes and explains differences in objectively measured moderate-to-vigorous physical activity (MVPA) in a socially and ethnically mixed sample of 6- to 11-year-old children in Germany. MVPA levels were objectively measured with accelerometers over the course of six consecutive days (Wednesday to Monday). Parents’ attitudes and practices as well as the family’s socio-economic status (SES) were assessed from the parents via questionnaires. Results indicate that MVPA levels of children vary with gender, but not with age and ethnicity. Moreover, parental SES, parental support for the child’s sports activities, parents’ own sport activities and the parents’ belief in sports’ capacities to foster personality development, character building and social integration significantly predict the MVPA level of children. It is concluded that interventions to promote MVPA among children need to take family interactions and lifestyles into account and should address families in socio-economically underprivileged areas.     

Effect of a behavioral intervention on dimensions of self-regulation and physical activity among overweight and obese adults with type 2 diabetes: a pilot study

The purpose of this pilot study was to determine the preliminary effect of a behavioral intervention on the use of self-regulation strategies and moderate-to-vigorous physical activity (MVPA) in overweight and obese adults with type 2 diabetes. 23 individuals recruited from ResearchMatc.org and campus advertisements were randomized into an intervention (n = 12) and control (n = 11) group. The intervention group received a behavioral intervention that used goal setting, time management, and self-monitoring to target dimensions of self-regulation and MVPA. The control received information regarding their PA habits. MVPA was measured via BodyMedia Armbands at pre- and post-test. The use of self-regulatory strategies for MVPA was assessed at pretest and posttest using the Self-Regulation for Exercise Scale. Cohen’s d effect sizes were calculated to determine the practical impact of the intervention. The intervention had a large effect on all dimensions of self-regulation across time: including total self-regulation (3.15), self-monitoring (4.63), goal setting (3.17), social support (1.29), self-reward (1.98), time management (4.41), and overcoming barriers (2.25). The intervention had no impact on dimensions of MVPA across time. This pilot study demonstrated the ability of a behavioral intervention to improve the use of self-regulation strategies for MVPA in a sample of adults with type 2 diabetes. These findings can further inform the development of health promotion programs to promote self-regulation. Future research should focus on determining ability of improvements in self-regulation to stimulate behavior change.     

Long-term effects of a dyadic planning intervention with couples motivated to increase physical activity

ObjectiveIn dyadic planning a target person and a planning partner create plans for when, where, and how the target person will change a health-relevant behavior. Across 52 weeks, direct and indirect effects of a dyadic-planning intervention on moderate-to-vigorous physical activity (MVPA) and physical fitness in target persons and their partners were investigated in a randomized controlled trial. Relationship quality was explored as a moderator.MethodsN = 338 couples (target persons randomized) were randomly assigned to a dyadic-planning- (DPC), an individual-planning- (IPC), or a no-planning dyadic-control condition (CC). MVPA was objectively assessed four times across 52 weeks using accelerometry. Physical fitness and proposed mediators (individual action control, received behavior-specific support and control) were repeatedly assessed. Relationship quality was measured at baseline. Latent growth curve-, multi-level-, and manifest mediation models were fit.ResultsAcross 52 weeks, MVPA of IPC and CC target persons increased. MVPA of DPC target persons remained stable, but those who reported high relationship quality increased their MVPA over time. DPC partners showed steeper increases in physical fitness when compared to IPC partners, but not CC partners. DPC partners’ increases in physical fitness were mediated by received support from target persons.ConclusionsThe dyadic planning intervention showed non-beneficial effects for target persons’ MVPA, but beneficial effects on their partners’ fitness. These findings resemble evidence from the social support literature indicating more benefits for support providers than for recipients.Trial registrationClinicalTrials.gov identifier: NCT01963494.     

Changes in physical activity and sedentary behavior associated with an exercise intervention in depressed adults

BackgroundExercise is beneficial for depression, but less is known about its impact on post-intervention physical activity and sedentary behavior. The aim of this paper was to determine the extent to which participation in light-, moderate- and vigorous-intensity exercise intervention influenced habitual physical activity and sedentary behavior patterns in depressed adults.MethodsAccelerometer data was collected pre- and post-intervention from depressed participants randomized to one of three 12-week intervention groups: light (n = 21), moderate (n = 25) and vigorous (n = 22) exercise. Mixed models examined changes in time spent sedentary and in light and moderate-to-vigorous physical activity (MVPA); time accumulated in sedentary and MVPA bouts; and, number of MVPA bouts and interruptions in sedentary time.ResultsOverall sedentary time decreased while light activity time increased across all intervention groups but not significantly so. The light exercise intervention group reduced MVPA minutes (−8.22, 95% CI: −16.44, −0.01), time in MVPA bouts (−8.44, 95% CI: −14.27, −2.62), and number of activity bouts (−0.43, 95% CI: −0.77, −0.09). The moderate exercise intervention group reduced time in MVPA bouts (−6.27, 95% CI: −11.71, −0.82) and number of sedentary interruptions (−6.07, 95% CI: −9.30, −2.84). No changes were observed for the vigorous exercise intervention group.ConclusionsThe exercise intervention led to an increase in overall light physical activity and decrease in sedentary time, though neither change was statistically significant. Participation in the light and moderate exercise intervention groups was associated with reductions of time in MVPA bouts, but this was not evident for the vigorous exercise intervention group.     

Achievement goal orientations,beliefs about sport success and sport emotions as related to moderate to vigorous physical activity of adolescents

Abstract

This study examined the relationships between achievement goals, beliefs about sport success and sport emotions with moderate to vigorous physical activity of Estonian adolescents. Three hundred and seventy five adolescents, aged 13–14 years, completed the Task and Ego Orientation in Sport Questionnaire and 7-day physical activity recall. Measures of the adolescent's orientation to work avoidance, focus on cooperation, beliefs about the causes of success and degree of satisfaction/interest specific to the context of sport and games were also included. Moderate to vigorous physical activity (MVPA) quartiles were determined and psychological measures for extreme activity groups were compared. A one-way ANOVA indicated that active males scored significantly higher in task orientation, motivation/effort, ability and enjoyment/interest whereas active females showed higher scores for cooperation and exercise enjoyment and lower deception and boredom compared with low activity groups. Correlation analysis revealed that in males, MVPA was related with task orientation, reported ability and motivation/ effort. For females, cooperation, and enjoyment of sport were positively and the amount of boredom was negatively associated with MVPA scores. Multiple regression analysis revealed that psychological measures explained only 14% (females) and 19% (males) of the variance in MVPA. It is concluded that for adolescent males and females, different psychological measures predicted MVPA behavior.     

Body-related emotions and subsequent physical activity behaviour: An ecological momentary assessment

Body-related shame and guilt are theorized to be time-varying affective determinants of physical activity, yet research has predominantly relied on self-report measures of physical activity and between-person associations. To address these limitations, the present study used ecological momentary assessment to examine within- and between-person associations between body-related shame and guilt, and subsequent time spent in moderate-to-vigorous physical activity (MVPA) measured by continuously worn accelerometers. University students (n = 98; 79.6% female; m_age = 19.45) were prompted 49 times over seven days to report body-related shame and guilt, and wore activPAL accelerometers to monitor movement behaviours. Higher levels of within-person body-related guilt, but not shame, were associated with increased subsequent time spent in MVPA. Contrary to existing literature, neither body-related shame nor guilt demonstrated a significant association with average levels of MVPA between individuals. These findings support theoretical propositions that body-related guilt may impact engagement in physical activity in daily life.     

Change in the social context of physical activity across adolescence and its association with moderate-to-vigorous intensity physical activity

We examined whether changes in social context (i.e., frequency with which youth engage in physical activity [PA] alone, with teammates, with friends, with siblings, or with parents/grandparents) is associated with change in moderate-to-vigorous intensity PA (MVPA) across Grades 5–8 and Grades 8–11 (N = 938). Data were self-reported annually. Across Grades 5–8, the frequency of PA in all social contexts declined over time, and changes in the frequency of PA alone, with teammates, with siblings, and in diversity of PA companion types were positively associated with change in MVPA. Across Grades 8–11, the frequency of PA with siblings, friends, and parents/grandparents declined over time, and changes in the frequency of PA alone, with teammates, with friends, with parents/grandparents, and in diversity of PA companion types were positively associated with change in MVPA. PA social contexts vary in how they associate with change in MVPA in youth over time.     

Global self-esteem,perceived athletic competence,and physical activity in children: A longitudinal cohort study

ObjectivesThe Exercise and Self-Esteem Model is used as a theoretical framework to describe associations between global self-esteem and physical activity, mediated by perceived athletic competence. We know little about how these associations develop over time in elementary school children. We examined the change in, and associations between, global self-esteem, perceived athletic competence, and moderate-to-vigorous physical activity (MVPA) in children from kindergarten to grade 4. We also investigated if this change and these associations were different for boys and girls.DesignA prospective longitudinal cohort-sequential design that consisted of two cohorts of children.MethodChildren in cohort I were followed from kindergarten to grade 2, and children in cohort II were followed from grade 2 to grade 4. Global self-esteem and perceived athletic competence were measured with the Self-Perception Profile for Children (SPPC) (n = 292; 148 boys), while MVPA was measured with proxy-reports for physical activity filled in by parents (n = 184; 88 boys).ResultsGlobal self-esteem, perceived athletic competence, and MVPA remained stable. Global self-esteem was the same in boys and girls, while boys reported higher levels of perceived athletic competence and were more physically active than girls. The change in global self-esteem was significantly associated with perceived athletic competence and MVPA in girls, but not in boys.ConclusionThere are few developmental changes in global self-esteem, perceived athletic competence, and MVPA from kindergarten to grade 4. The change in global self-esteem was associated with perceived athletic competence and MVPA in girls, but not in boys.