Additional effects of a cognitive task on dual-task training to reduce dual-task interference

ObjectiveWhen we perform dual-tasks in daily life, task performance is generally reduced. As these reductions in performance (i.e., dual-task interference) are responsible for various accidents such as falls, the repeated practice of dual-task (i.e., dual-task training) is often implemented to reduce dual-task interference. However, the risk of various accidents increases with longer dual-task training, as dual-task interference cannot be avoided. Therefore, it is important to achieve training goals more rapidly during dual-task training. This study sought to determine whether a combination of dual-task training and cognitive tasks would accelerate training effects.DesignThe experimental design included four groups: 1) cognitive task training group, 2) dual-task training group, 3) cognitive task and dual-task training group, and 4) non training group.MethodWe assessed single- and dual-task performance before and after the 2-week training sessions. We adopted a dual-task involving knee extension and an auditory reaction, and used N-back task as a cognitive task. On the other hand, dual-task training was the same method to assess dual-task performance.ResultDual-task interference was reduced in all groups in both the tasks. However, the number of participants in the cognitive task and dual-task training group who achieved a reduction in dual-task cost was significantly higher than those in other groups.ConclusionThese findings could contribute to the development of an effective method for reducing dual-task interference and resolving issues caused by dual-task interference in daily life.     

Cerebellar contributions to tactile perception in people with varying sensorimotor experiences: Examining the sensory acquisition hypothesis

The sensory acquisition hypothesis states that the sensory demand of a task is the most crucial factor in determining the level of cerebellar activity. The present study was conducted to examine whether the prediction of sensory demand holds when participants have different sensorimotor training experiences. Archery athletes and non-athletic control participants were asked to perform tactile discrimination tasks during fMRI scanning. In archery athletes, a pattern of reduced cerebellar activation accompanying higher sensory cortical activity was observed, whereas in non-athletic control participants the visual network was found to be in concert with extensive cerebellar activation. These findings are in accordance with the prediction that the cerebellum plays a supportive role for the cerebral cortex in sensory data acquisition.     

Affective-Evaluative Learning in Humans: A Form of Associative Learning or Only an Artifact?

The status of evaluative conditioning (EC) as a distinct form of associative learning was called in question by Field and Davey (1997, 1998, 1999), who argued that in the typical visual EC paradigm, nonassociative visual concept learning is responsible for the evaluative changes observed. Especially, the use of only within-subject control conditions instead of independent control groups was criticized. The present three experiments show (a) that EC effects can be demonstrated within another sensory modality than visual perception and (b) that EC effects are demonstrable in a between-subject design (including a successful replication attempt). A further result was that these EC effects do not require participants' conscious awareness. The data provide no support for an artifactual account of EC but suggest an interpretation of EC as a form of associative learning.     

Exposure to rf electromagnetic energy decreases aggressive behavior

It was predicted from the dopamine-opiate system hypothesis that aggression induced by light tail pressure would be modified by exposure of the animals to radiofrequency electromagnetic energy. In a series of three experiments, it was found that there was a substantial decrease in aggressive behavior during exposure to EM energy at incident power densities as low as 50 μW/cm². This is consistent with previously published reports that indicate the dopamine and opiate systems of the brain are influenced by exposure to low-intensity EM energy. It would appear that EM energy exposure could be used as a probe in the study of aggression and in relating it to brain chemistry. Since this energy has become ubiquitous in the environment, and quite uneven in distribution, there may be implications for understanding aggressive behavior from a clinical standpoint as well as from the standpoint of necessary controls in experiments.     

左侧背外侧前额叶在程序性运动学习中的作用

程序性运动学习包括序列学习和随机学习。神经影像学研究表明背外侧前额叶皮层(DLPFC)和初级运动皮层(M1)在程序性运动学习中发挥重要作用, 但DLPFC和M1之间的联通性及其与不同程序性运动学习的关系尚不明确。本研究采用连续反应时间任务, 结合经颅磁刺激(TMS)方法, 探讨左侧DLPFC到M1的联通性在不同程序性运动学习中的差异。实验1采用两连发TMS探测DLPFC到M1的最佳投射时间点; 实验2, 被试分为2组, 分别进行序列学习和随机学习, 在学习前、后采集行为学数据, 以及M1的运动诱发电位和DLPFC-M1联通性的电生理学数据。行为学结果发现序列学习组的学习效果更佳; 电生理学结果发现, 两组被试学习前、后M1的运动诱发电位均未发生改变; 在最佳时间投射点、适当刺激强度下, 序列学习组DLPFC-M1联通性发生改变, 且与学习成绩相关, 而随机学习组没有改变。结果说明DLPFC到M1的联通性增强可能是序列学习成绩更佳的重要原因, 这一结果从电生理角度为DLPFC在运动学习中的作用提供了重要证据。     

Stimulus factors in the isolation-induced aggression of Bobwhite quail and Khaki Campbell ducklings

Two studies examined the relative abilities of conspecific-derived visual and tactile stimulation to modulate the occurrence of isolation-induced aggression in Bobwhite quail and Khaki Campbell ducklings. In Experiment 1, subjects were permitted visual stimulation from conspecifics but were deprived of conspecific tactile stimulation. In both species, these subjects subsequently showed significantly less aggression towards conspecifics than birds that had been deprived of both visual and tactile stimulation from conspecifics. In Experiment 2, one group of subjects was permitted conspecific tactile stimulation but was deprived of conspecific visual stimulation. Again for both species, these subjects subsequently exhibited significantly less aggressive behavior towards conspecifics than did subjects that had been both visually and tactually de-prived. In sum, the present research suggests that both tactile and visual stimulation from a conspecific are individually sufficient to reduce isolation-induced aggression in these precocial buds.     

Conceptual ambiguities and measurement issues in sensory processing sensitivity

The aim of the article is (1) to critically discuss Sensory Processing Sensitivity (SPS) in light of personality theories and (2) to examine the validity of the only available measure of SPS, the Highly Sensitive Person Scale (HSPS). Study 1 (N = 289) examines the relations of the HSPS with facets of the Big Five. In Study 2 (N = 226), the HSPS’ relation to emotion recognition ability is estimated after controlling for the Big Five. In contrast to previous studies, these relationships are estimated at the level of latent variables. Our data suggest that SPS highly overlaps with established personality traits, and its relation with emotion recognition ability can be fully explained by Neuroticism and Openness to Experience.     

Sensory attenuation of action outcomes of varying amplitude and valence

Stimuli caused by self-initiated actions are perceived as less intense than those caused externally; this effect is called sensory attenuation (SA). In two experiments, we aimed to assess the impact of the amplitude of outcomes and its affective valence on SA and explicit ratings of sense of agency. This allowed us to test the predictions of the available SA frameworks and better understand the link between SA, affect, and agency. The results indicated that SA can be reversed, and such sensory amplification is driven by low-amplitude and positive-valence outcomes. We also show that intentional action influences the perceived valence of outcomes, and that modulations of explicit sense of agency are divergent from those of SA. Our study shows that valence influences the processing of the amplitude of intentional action outcomes and suggests that none of the currently available frameworks give full justice to SA’s variability.     

重复经颅磁刺激对轻度认知障碍的干预效果

轻度认知障碍(mild cognitive impairment, MCI)是介于正常认知老化和老年痴呆的中间状态, 目前尚无有效的药物治疗方案。重复经颅磁刺激(repetitive transcranial magnetic stimulation, rTMS)可通过诱导突触可塑性的改变来改善大脑的认知功能。对rTMS干预MCI认知功能的有效性及神经机制进行分析。未来研究应优化定位手段, 延长对干预效果的随访评估, 考察不同刺激参数和刺激靶区对干预有效性的影响, 以及结合脑成像技术来探索rTMS的干预机制。