贝叶斯因子及其在JASP中的实现

统计推断在科学研究中起到关键作用,然而当前科研中最常用的经典统计方法——零假设检验(Null hypothesis significance test,NHST)却因难以理解而被部分研究者误用或滥用。有研究者提出使用贝叶斯因子(Bayes factor)作为一种替代和(或)补充的统计方法。贝叶斯因子是贝叶斯统计中用来进行模型比较和假设检验的重要方法,其可以解读为对零假设H_0或者备择假设H_1的支持程度。其与NHST相比有如下优势:同时考虑H_0和H_1并可以用来支持H_0、不"严重"地倾向于反对H_0、可以监控证据强度的变化以及不受抽样计划的影响。目前,贝叶斯因子能够很便捷地通过开放的统计软件JASP实现,本文以贝叶斯t检验进行示范。贝叶斯因子的使用对心理学研究者来说具有重要的意义,但使用时需要注意先验分布选择的合理性以及保持数据分析过程的透明与公开。

多中心合作和可重复的心理与脑科学研究

心理与脑科学研究结果的可重复性问题近年来备受关注。这一问题的根源一般被认为有两个方面:客观存在的方法学问题和研究者有意或无意的可疑研究操纵。开展可重复的心理与脑科学研究已经为越来越多的研究者所接受和推崇,正在成为新的趋势。本文从多中心合作的视角,就多中心合作研究模式在开展可重复的心理与脑科学研究中的应用和发展,以及应用过程中需要注意的问题展开讨论。希望国内心理与脑科学同行,尤其是年轻研究者加强多中心合作研究相关的方法学训练,以更开放的心态联合起来,开展稳健、可重复的心理与脑科学研究。

团队科学研究方法在可重复的心理与脑科学研究中的应用

近年来,研究结果的可重复性问题在多个领域引起了广泛关注。然而,在心理与脑科学领域中导致一些研究结果不可重复的原因是复杂的。例如,研究对象、研究范式和研究变量的复杂性、出版偏见(publication bias)等都会导致研究结果的不可重复。鉴于这些复杂的因素,我们很难明确一些研究结果不可重复的具体原因:可能是小样本研究导致效应量被高估,也可能是重复实验与原实验不同群体样本导致数据偏差,还可能是研究过程中存在有意或无意的有问题做法。目前,开展可重复的心理与脑科学研究已经被越来越多的研究者所重视和推崇,并逐渐成为新的趋势。针对如何开展可重复的研究,一些研究者从方法学和实践的角度进行了诸多讨论,如数据采集前的样本预估、研究预注册(preregistration)、阴性结果发表、数据共享等。这里笔者主要结合自己的研究经历,就团队合作研究方法(team science)在开展可重复研究中的应用和可能的挑战做一些分享。

Isochronous singing in 3 crested gibbon species(Nomascus spp.)

The search for common characteristics between the musical abilities of humans and other animal species is still taking its frst steps.One of the most promising aspects from a comparative point of view is the analysis of rhythmic components,which are crucial features of human communicative performance but also well-identifable patterns in the vocal displays of other species.Therefore,the study of rhythm is becoming essential to understand the mechanisms of singing behavior and the evolution of human communication.Recent fndings provided evidence that particular rhythmic structures occur in human music and some singing animal species,such as birds and rock hyraxes,but only 2 species of nonhuman primates have been investigated so far(Indri indri and Hylobates lar).Therefore,our study aims to consistently broaden the list of species studied regarding the presence of rhythmic categories.We investigated the temporal organization in the singing of 3 species of crested gibbons(Nomascus gabriellae,Nomascus leucogenys,and Nomascus siki)and found that the most prominent rhythmic category was isochrony.Moreover,we found slight variation in songs’tempo among species,with N.gabriellae and N.siki singing with a temporal pattern involving a gradually increasing tempo(a musical accelerando),and N.leucogenys with a more regular pattern.Here,we show how the prominence of a peak at the isochrony establishes itself as a shared characteristic in the small apes considered so far.

Humans identify negative （but not positive） arousal in silver fox vocalizations： implications for the adaptive value of interspecific eavesdropping

The ability to identify emotional arousal in heterospecific vocalizations may facilitate behaviors that increase survival opportunities. Crucially, this ability may orient inter-species interactions, par- ticularly between humans and other species. Research shows that humans identify emotional arousal in vocalizations across multiple species, such as cats, dogs, and piglets. However, no previ- ous study has addressed humans＂ ability to identify emotional arousal in silver foxes. Here, we adopted low- and high-arousal calls emitted by three strains of silver fox--Tame, Aggressive, and Unselected--in response to human approach. Tame and Aggressive foxes are genetically selected for friendly and attacking behaviors toward humans, respectively. Unselected foxes show aggres- sive and fearful behaviors toward humans. These three strains show similar levels of emotional arousal, but different levels of emotional valence in relation to humans. This emotional information is reflected in the acoustic features of the calls. Our data suggest that humans can identify high- arousal calls of Aggressive and Unselected foxes, but not of Tame foxes. Further analyses revealed that, although within each strain different acoustic parameters affect human accuracy in identifying high-arousal calls, spectral center of gravity, harmonic-to-noise ratio, and F0 best predict humans＇ ability to discriminate high-arousal calls across all strains. Furthermore, we identified in spectral center of gravity and F0 the best predictors for humans＇ absolute ratings of arousal in each call. Implications for research on the adaptive value of inter-specific eavesdropping are discussed.

White Matter Abnormalities in Major Depression Biotypes Identified by Diffusion Tensor Imaging

Identifying data-driven biotypes of major depressive disorder(MDD) has promise for the clarification of diagnostic heterogeneity. However, few studies have focused on white-matter abnormalities for MDD subtyping. This study included 116 patients with MDD and118 demographically-matched healthy controls assessed by diffusion tensor imaging and neurocognitive evaluation.Hierarchical clustering was applied to the major fiber tracts, in conjunction with tract-based spatial statistics, to reveal white-matter alterations associated with MDD.Clinical and neurocognitive differences were compared between identified subgroups and healthy controls. With fractional anisotropy extracted from 20 fiber tracts, cluster analysis revealed 3 subgroups based on the patterns of abnormalities. Patients in each subgroup versus healthy controls showed a stepwise pattern of white-matter alterations as follows: subgroup 1(25.9% of patient sample),widespread white-matter disruption;subgroup 2(43.1% of patient sample), intermediate and more localized abnormalities in aspects of the corpus callosum and left cingulate;and subgroup 3(31.0% of patient sample),possible mild alterations, but no statistically significant tract disruption after controlling for family-wise error. The neurocognitive impairment in each subgroup accompanied the white-matter alterations: subgroup 1, deficits in sustained attention and delayed memory;subgroup 2, dysfunction in delayed memory;and subgroup 3, no significant deficits. Three subtypes of white-matter abnormality exist in individuals with major depression, those having widespread abnormalities suffering more neurocognitive impairments, which may provide evidence for parsing the heterogeneity of the disorder and help optimize typespecific treatment approaches.

Neurocognitive Graphs of First-Episode Schizophrenia and Major Depression Based on Cognitive Features

Neurocognitive deficits are frequently observed in patients with schizophrenia and major depressive disorder(MDD). The relations between cognitive features may be represented by neurocognitive graphs based on cognitive features, modeled as Gaussian Markov random fields. However, it is unclear whether it is possible to differentiate between phenotypic patterns associated with the differential diagnosis of schizophrenia and depression using this neurocognitive graph approach. In this study, we enrolled 215 first-episode patients with schizophrenia(FES), 125 with MDD, and 237 demographically-matched healthy controls(HCs). The cognitive performance of all participants was evaluated using a battery of neurocognitive tests. The graphical LASSO model was trained with aone-vs-one scenario to learn the conditional independent structure of neurocognitive features of each group. Participants in the holdout dataset were classified into different groups with the highest likelihood. A partial correlation matrix was transformed from the graphical model to further explore the neurocognitive graph for each group. The classification approach identified the diagnostic class for individuals with an average accuracy of 73.41% for FES vs HC, 67.07% for MDD vs HC, and 59.48% for FES vs MDD. Both of the neurocognitive graphs for FES and MDD had more connections and higher node centrality than those for HC. The neurocognitive graph for FES was less sparse and had more connections than that for MDD.Thus, neurocognitive graphs based on cognitive features are promising for describing endophenotypes that may discriminate schizophrenia from depression.

How small could a pup sound？ The physical bases of signaling body size in harbor seals

Vocal communication is a crucial aspect of animal behavior. The mechanism which most mam- mals use to vocalize relies on three anatomical components. First, air overpressure is generated in- side the lower vocal tract. Second, as the airstream goes through the glottis, sound is produced via vocal fold vibration. Third, this sound is further filtered by the geometry and length of the upper vocal tract. Evidence from mammalian anatomy and bioacoustics suggests that some of these three components may covary with an animal＇s body size. The framework provided by acoustic al- Iometry suggests that, because vocal tract length （VTL） is more strongly constrained by the growth of the body than vocal fold length （VFL）, VTL generates more reliable acoustic cues to an animal＇s size. This hypothesis is often tested acoustically but rarely anatomically, especially in pinnipeds. Here, we test the anatomical bases of the acoustic allometry hypothesis in harbor seal pups Phoca vitulina. We dissected and measured vocal tract, vocal folds, and other anatomical features of 15 harbor seals post-mortem. We found that, while VTL correlates with body size, VFL does not. This suggests that, while body growth puts anatomical constraints on how vocalizations are filtered by harbor seals＇ vocal tract, no such constraints appear to exist on vocal folds, at least during puppy- hood. It is particularly interesting to find anatomical constraints on harbor seals＇ vocal tracts, the same anatomical region partially enabling pups to produce individually distinctive vocalizations.