The role of affect in the decision to exercise: Does being happy lead to a more active lifestyle?

ObjectiveThis study investigated the influence of affect on individuals' intentions to engage in physical activities such as exercise. Behavior intentions were examined through the Theory of Planned Behavior (TPB).MethodAn experimental survey was conducted among 153 undergraduates randomly assigned to three conditions – positive affect, neutral, and negative affect. Key variables from the TPB were assessed across these conditions.ResultsAnalyses showed that participants in the positive affect and the negative affect conditions reported lower intentions to exercise than those in the neutral condition. Participants in the negative affect condition also reported more unfavorable attitudes toward exercise than their positive or neutral counterparts. Other TPB measures remained stable across the three conditions. In particular, perceived behavioral control and attitude were significant predictors of behavior intention in the pooled sample.ConclusionThese results underline the important role that affect, especially negative affect, plays in individuals' decision to exercise. Rational models for health behavior change, such as the TPB, should take into account the impact of affect.     

Adolescent Neural Responses to Antismoking Messages,Perceived Effectiveness,and Sharing Intention

ABSTRACT

Health communication delivered via media channels can substantially influence adolescents’ choices, and the effects of messages are amplified through interpersonal sharing. However, the underlying psychological and neurocognitive mechanisms that influence message effectiveness and likelihood of sharing are not well understood, especially among adolescents. Based on research in adults, we hypothesized and preregistered that message-induced neural activation in regions associated with self-reflection, social processing, and positive valuation would be related to greater perceived ad effectiveness and intentions to share messages. We focused on brain activity in meta-analytically defined regions associated with these three processes as 40 adolescent nonsmokers viewed advertisements from “The Real Cost” antismoking campaign. Perceived message effectiveness was positively associated with brain activity in the hypothesized social processing regions and marginally associated with brain activity in self-relevance regions, but not associated with brain activity in valuation regions. By contrast, intentions to share the messages were not associated with neural response in these 3 systems. In contrast to previous neuroimaging studies with adult subjects, our findings highlight the role of social cognition in adolescent processing of persuasive messages. We discuss the possibility that the mental processes responsive to effective and shareworthy messages may reflect developmental processes pertinent to media effects.     

Short-Term Violent Video Game Play by Adolescents Alters Prefrontal Activity During Cognitive Inhibition

Prior research has indicated an association between exposure to violent media and aggressive thoughts, feelings, and behavior, potentially as a result of effects on inhibitory mechanisms. However, the role of violence in video games in modulating subsequent neural activity related to cognitive inhibition has received little attention. To examine short-term effects of playing a violent video game, 45 adolescents were randomly assigned to play either a violent or a nonviolent video game for 30 minutes immediately prior to functional magnetic resonance imaging (fMRI). During the fMRI procedure, participants performed a go/no-go task that required them to press a button for each target stimulus and withhold the response for non-target stimuli. Participants who played the violent game demonstrated a lower BOLD response in right dorsolateral prefrontal cortex (DLPFC) when responses were appropriately inhibited. The DLPFC is involved with executive functioning, including suppression of unwanted thoughts and behaviors. In addition, responses in the DLPFC demonstrated stronger inverse connectivity with precuneus in the nonviolent game players. These results provide evidence that playing a violent video game can modulate prefrontal activity during cognitive inhibition.     

视觉工作记忆对自上而下注意控制的影响:发展视角的探讨

注意控制探讨个体以何种方式选择性地注意外界信息。本研究从发展角度探讨视觉工作记忆对自上而下注意控制的影响。研究采用记忆任务与视觉搜索任务相结合的范式,以小学三、四、五年级学生为被试,从视觉工作记忆中信息性质和视觉工作记忆负荷两个角度考察了视觉工作记忆对自上而下注意控制影响的发展特点。结果发现,(1)自上而下注意控制能力存在年级差异,小学五年级学生的成绩显著优于小学三年级学生;(2)视觉工作记忆内容影响自上而下注意控制,目标相关信息促进目标搜索,而目标无关信息干扰目标搜索;(3)视觉工作记忆负荷影响自上而下注意控制,高视觉工作记忆负荷条件下的反应时显著长于低视觉工作记忆负荷。     

Individuals with congenital amusia imitate pitches more accurately in singing than in speaking: Implications for music and language processing

In this study, we investigated the impact of congenital amusia, a disorder of musical processing, on speech and song imitation in speakers of a tone language, Mandarin. A group of 13 Mandarin-speaking individuals with congenital amusia and 13 matched controls were recorded while imitating a set of speech and two sets of song stimuli with varying pitch and rhythm patterns. The results indicated that individuals with congenital amusia were worse than controls in both speech and song imitation, in terms of both pitch matching (absolute and relative) and rhythm matching (relative time and number of time errors). Like the controls, individuals with congenital amusia achieved better absolute and relative pitch matching and made fewer pitch interval and contour errors in song than in speech imitation. These findings point toward domain-general pitch (and time) production deficits in congenital amusia, suggesting the presence of shared pitch production mechanisms but distinct requirements for pitch-matching accuracy in language and music processing.     

Positive affect improves working memory: Implications for controlled cognitive processing

This study examined the effects of positive affect on working memory (WM) and short-term memory (STM). Given that WM involves both storage and controlled processing and that STM primarily involves storage processing, we hypothesised that if positive affect facilitates controlled processing, it should improve WM more than STM. The results demonstrated that positive affect, compared with neutral affect, significantly enhanced WM, as measured by the operation span task. The influence of positive affect on STM, however, was weaker. These results suggest that positive affect enhances WM, a task that involves controlled processing, not just storage processing. Additional analyses of recall and processing times and accuracy further suggest that improved WM under positive affect is not attributable to motivational differences, but results instead from improved controlled cognitive processing.     

Altered topological patterns of large-scale brain functional networks during passive hyperthermia

In this study, we simulated environmental heat exposure to 18 participants, and obtained functional magnetic resonance image (fMRI) data during resting state. Brain functional networks were constructed over a wide range of sparsity threshold according to a prior atlas dividing the whole cerebrum into 90 regions. Results of graph theoretical approaches showed that although brain networks in both normal and hyperthermia conditions exhibited economical small-world property, significant alterations in both global and nodal network metrics were demonstrated during hyperthermia. Specifically, a lower clustering coefficient, maintained shortest path length, a lower small-worldness, a lower mean local efficiency were found, indicating a tendency shift to a randomized network. Additionally, significant alterations in nodal efficiency were found in bilateral gyrus rectus, bilateral parahippocampal gyrus, bilateral insula, right caudate nucleus, bilateral putamen, left temporal pole of middle temporal gyrus, right inferior temporal gyrus. In consideration of physiological system changes, we found that the alterations of normalized clustering coefficient, small-worldness, mean normalized local efficiency were significantly correlated with the rectal temperature alteration, but failed to obtain significant correlations with the weight loss. More importantly, behavioral attention network test (ANT) after MRI scanning showed that the ANT effects were altered and correlated with the alterations of some global metrics (normalized shortest path length and normalized global efficiency) and prefrontal nodal efficiency (right dorsolateral superior frontal gyrus, right middle frontal gyrus and left orbital inferior frontal gyrus), implying behavioral deficits in executive control effects and maintained alerting and orienting effects during passive hyperthermia. The present study provided the first evidence for human brain functional disorder during passive hyperthermia according to graph theoretical analysis using resting-state fMRI.     

Congruency sequence effect in cross-task context: Evidence for dimension-specific modulation

The congruency sequence effect refers to a reduced congruency effect after incongruent trials relative to congruent trials. This modulation is thought to be, at least in part, due to the control mechanisms resolving conflict. The present study examined the nature of the control mechanisms by having participants perform two different tasks in an alternating way. When participants performed horizontal and vertical Simon tasks in Experiment 1A, and horizontal and vertical spatial Stroop task in Experiment 1B, no congruency sequence effect was obtained between the task congruencies. When the Simon task and spatial Stroop task were performed with different response sets in Experiment 2, no congruency sequence effect was obtained. However, in Experiment 3, in which the participants performed the horizontal Simon and spatial Stroop tasks with an identical response set, a significant congruency sequence effect was obtained between the task congruencies. In Experiment 4, no congruency sequence effect was obtained when participants performed two tasks having different task-irrelevant dimensions with the identical response set. The findings suggest inhibitory processing between the task-irrelevant dimension and response mode after conflict.     

Crossover from bulk to surface diffusion in the fluctuations of step edges on Pt(111)

Using low-energy electron microscopy we explore the fluctuations of step edges on Pt(111) in the temperature range 1190?K<T<1520?K. Below 1400?K the relaxation times vary with wave vector q as q ³, and above 1400?K as q ², while the observed activation energy changes from 1.25 to 2.75?eV. A discussion shows that surface diffusion is responsible for the rates at low temperatures, and that bulk vacancy diffusion becomes dominant above 1400?K. We infer that a similar crossover must occur for steps on most metal surfaces. The step stiffness is determined as 175 ± 20?meV?nm^?1 at 1500?K.     

A novel method for measurement of electronic work function of micro/nanostructure materials using a Kelvin probe system

Work function (WF) can be measured using the Kelvin probe (KP) technique to characterize surface behavior of micro/nanostructures grown on substrates such as metals or semiconductors. However, for such micro/nanostructures, substrates with different WF can strongly affect the measurements if they are exposed directly to face the Kevin probe tip. In this article, a model is proposed to investigate the WF of sparse ZnO nanorods grown on an Si substrate. It is demonstrated that theoretical results from the model are consistent with experimental observations performed using a KP system.