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。     

Microstructural white matter alterations and personality traits: A diffusion MRI study

Personality traits refer to a set of independent patterns of behaviour, cognition, and emotion. The Big-Five of Personality (NEO-FFI), is one of the most generally recognized taxonomies of personality. The current structural and functional correlates of personality are divergent and inconsistent in some cases, which necessitate further investigation of it. Herein, we aimed to investigate the white matter (WM) microstructural correlates of personality traits using diffusion MRI connectometry. Overall, the main findings of this study were located in different parts of the corpus callosum (CC) and middle cerebellar peduncle (MCP), highlighting the significant role of WM local connectome in the CC and MCP in the regulation of personality traits. Future studies need to validate our results.     

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.     

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。     

Musical groove modulates motor cortex excitability: A TMS investigation

Groove is often described as a musical quality that can induce movement in a listener. This study examines the effects of listening to groove music on corticospinal excitability. Musicians and non-musicians listened to high-groove music, low-groove music, and spectrally matched noise, while receiving single-pulse transcranial magnetic stimulation (TMS) over the primary motor cortex either on-beat or off-beat. We examined changes in the amplitude of the motor-evoked potentials (MEPs), recorded from hand and arm muscles, as an index of activity within the motor system. Musicians and non-musicians rated groove similarly. MEP results showed that high-groove music modulated corticospinal excitability, whereas no difference occurred between low-groove music and noise. More specifically, musicians’ MEPs were larger with high-groove than low-groove music, and this effect was especially pronounced for on-beat compared to off-beat pulses. These results indicate that high-groove music increasingly engages the motor system, and the temporal modulation of corticospinal excitability with the beat could stem from tight auditory–motor links in musicians. Conversely, non-musicians’ MEPs were smaller for high-groove than low-groove music, and there was no effect of on- versus off-beat pulses, potentially stemming from suppression of overt movement. In sum, high-groove music engages the motor system, and previous training modulates how listening to music with a strong groove activates the motor system.     

经颅直流电刺激右侧颞顶联合区对道德意图加工的影响*

对行为意图的理解是人类进行道德判断的重要依据,大量研究表明,右侧颞顶联合区是意图加工的关键脑区。为考察该脑区在道德判断中的重要作用,采用经颅直流电刺激技术阳极刺激右侧颞顶联合区,探讨促进该脑区的活动对被试在道德判断中意图及相关信息加工的影响。结果发现与假刺激条件相比,阳极刺激后道德判断反应时显著延长,在伤人未遂和意外伤人条件下差异显著,证明促进右侧颞顶联合区的激活能影响道德判断中的意图加工,尤其在意图与结果产生冲突的条件下效应更加显著。     

Contextual Interference Effect: Elaborative Processing or Forgetting—Reconstruction? A Post Hoc Analysis of Transcranial Magnetic Stimulation—Induced Effects on Motor Learning

The elaborative-processing and forgetting-reconstruction hypotheses are the 2 principal explanations for the contextual interference (CI) effect. The present authors' purpose was to identify which of these 2 hypotheses better accounts for the CI effect. They synchronized single transcranial magnetic stimulation (TMS) pulses to each intertrial interval to modulate information processing during Blocked and Random Practice conditions. Participants practiced 3 arm tasks with either a Blocked or Random Practice order. The 3 stimulation conditions (No TMS, TMS, Sham TMS) by 2-practice order (Blocked, Random) between-participant design resulted in 6 experimental groups. Without TMS, motor learning increased under Random Practice. With TMS, this learning benefit diminished. These results support the elaborative-processing hypothesis by showing that perturbing information processing, evoked by Random Practice, deteriorates the learning benefit. Unlike the prediction of the forgetting—reconstruction hypothesis, adding perturbation during Blocked Practice did not significantly enhance motor learning.