Dreaming in the multilevel framework

Biological realism ( [Revonsuo, 2001] and [Revonsuo, 2006] ) states that dreaming is a biological phenomenon and therefore explainable in naturalistic terms, similar to the explanation of other biological phenomena. In the biological sciences, the structure of explanations can be described with the help of a framework called ‘multilevel explanation’. The multilevel model provides a context that assists to clarify what needs to be explained and how, and how to place different theories into the same model. Here, I will argue that the multilevel framework would be useful when we try to construct scientific explanations of dreaming.     

The perception of biological and mechanical motion in female fragile X premutation carriers

Previous studies reported impaired visual information processing in patients with fragile X syndrome and in premutation carriers. In this study, we assessed the perception of biological motion (a walking point-light character) and mechanical motion (a rotating shape) in 25 female fragile X premutation carriers and in 20 healthy non-carrier controls. Stimuli were moving stimulus dots embedded among a cloud of noise dots. Sensitivity (d′) for motion detection was determined. Emotional symptoms were assessed by Hamilton’s depression and anxiety rating scales. Results revealed that the premutation carriers displayed lower sensitivities for biological and mechanical motion relative to the non-carriers. This deficit was more pronounced in the case of biological stimuli. The premutation carriers displayed higher depression and anxiety scores relative to the non-carriers. Higher depression, but not anxiety, scores were associated with decreased sensitivity for biological, but not mechanical, motion in the carrier group. These results suggest that motion perception deficits are detectable in fragile X premutation carriers, and that the impairment of biological motion perception is associated with depressive symptoms.     

Sex differences in response to a panicogenic challenge procedure: an experimental evaluation of panic vulnerability in a non-clinical sample

Epidemiological studies show that women are twice as likely as men to develop panic disorder (PD) during their lifetimes. Data from retrospective studies also suggest that women are more distressed by panic and other negative emotional states than men, and that this tendency may precede the development of PD. The present prospective study sought to expand this work by evaluating sex differences in the predisposition to panic in individuals without PD or other forms of psychopathology. Participants (N=96; 52 women) were exposed to 12 panicogenic inhalations of 20% CO2-enriched air while physiological (e.g., heart rate, electrodermal response, Frontalis EMG) and self-report (e.g., subject distress, fear, frequency and severity of DSM-IV panic symptoms) response domains were monitored. As expected, magnitude of autonomic responding failed to reliably discriminate between women and men. Yet, women reported more fear and panic immediately following the challenge procedure relative to men, and this sex difference persisted when assessed again 30 min post-challenge. Implications of these results are discussed broadly in the context of biopsychosocial accounts of sex differences in the clinical presentation of PD.     

A bird's eye view: biological categorization and reasoning within and across cultures

Many psychological studies of categorization and reasoning use undergraduates to make claims about human conceptualization. Generalizability of findings to other populations is often assumed but rarely tested. Even when comparative studies are conducted, it may be challenging to interpret differences. As a partial remedy, in the present studies we adopt a 'triangulation strategy' to evaluate the ways expertise and culturally different belief systems can lead to different ways of conceptualizing the biological world. We use three groups (US bird experts, US undergraduates, and ordinary Itza' Maya) and two sets of birds (North American and Central American). Categorization tasks show considerable similarity among the three groups' taxonomic sorts, but also systematic differences. Notably, US expert categorization is more similar to Itza' than to US novice categorization. The differences are magnified on inductive reasoning tasks where only undergraduates show patterns of judgment that are largely consistent with current models of category-based taxonomic inference. The Maya commonly employ causal and ecological reasoning rather than taxonomic reasoning. Experts use a mixture of strategies (including causal and ecological reasoning), only some of which current models explain. US and Itza' informants differed markedly when reasoning about passerines (songbirds), reflecting the somewhat different role that songbirds play in the two cultures. The results call into question the importance of similarity-based notions of typicality and central tendency in natural categorization and reasoning. These findings also show that relative expertise leads to a convergence of thought that transcends cultural boundaries and shared experiences.     

Examining college students' food security coping strategies and experiences during the COVID-19 pandemic

College students' food situations may have been disrupted by the COVID-19 pandemic, which could have affected their health and well-being. However, little is known about how the pandemic impacted students' food experiences and how students coped with food-related disruptions, particularly from the student's own perspective. This study reviews data from 571 undergraduates who attended public colleges during Fall 2021 and Spring 2022 and wrote a narrative about the pandemic's impact on their food experiences. Most students indicated they experienced a wide range of food difficulties and adapted new food practices. Despite these challenges, students emphasized proactive coping strategies and positive pandemic outcomes rather than difficulties and negative outcomes. These findings have implications for students' long-term health and well-being.     

迎接21世纪生命科学的新时代：———基因组与蛋白组计划时代

当全世界人类基因组计划在近年取得迅速和突出的进展,即将来临床的２１世纪将带领人类基因组计,划进入一个基基因组时代、蛋白组计划、生物信息学的新时代,所有这些将构成２１世纪生命科学研究的核心前沿和主流。同亲,生物信息学的成果将高度地拓展生命科学新的研究领域和加速其研究的里程。多种多样数以千万计的生命模式（如生物大分子结构功能的模式）的数字化,将是加快生命科学信息化步入一个崭新的水平和时代的必由之路。     

Using the simultaneous protocol to study equivalence class formation: the facilitating effects of nodal number and size of previously established equivalence classes

The emergence of equivalence classes in college students is unlikely when all baseline relations are trained concurrently and all probes for emergent relations are then introduced concurrently (the simultaneous protocol). This experiment showed how the number of nodes and the size of previously established equivalence classes enhanced the emergence of new equivalence classes under the simultaneous protocol. First, one-node three-, five-, or seven-member classes or three-node five- or seven-member classes were established with college students. A sixth group received no pretraining. Then, the simultaneous protocol was used to establish new three-node five-member equivalence classes with all students. The speed and variability with which the baseline relations were established in the simultaneous protocol were inverse functions of number of nodes in the previously established classes, but not of their size. The percentage of subjects who showed the emergence of new equivalence classes under the simultaneous protocol was a direct function of number of nodes and size of pretrained classes. The additional time spent for pretraining greatly reduced the total training time needed to produce individuals who showed the emergence of classes under the simultaneous protocol. The total time saved was a direct function of number of nodes and number of stimuli in the pretrained classes.     

Do children have to remember to reason? A fuzzy-trace theory of transitivity development

An idea that has become commonplace in the literature on cognitive development is that the solution of thinking and reasoning problems requires that children retain accurate representations of certain background facts in short-term memory. This reasoning/remembering hypothesis is reexamined with reference to the one childhood cognitive task for which the validity of the hypothesis seems to be firmly established, transitive inference. Although the hypothesis says that children's transitive inferences are critically dependent on memory for the initial premise information, it is shown in six experiments that transitivity and premise memory are independent abilities in children. A fuzzy-trace theory is developed to explain this surprising independence effect. The theory assumes that children retain only degraded, schematic representations (fuzzy traces) of the overall pattern of an ordered series and that performance on subsequent test trials is mediated by processing operations that flesh out vague pattern information. Some further experiments that were designed to test various predictions of the fuzzy-trace theory are reported. Last, it is shown that reasoning and remembering are independent abilities in some other childhood cognitive tasks for which the initial background facts are not logically inescapable components of the eventual solution. These reasoning/remembering independence effects argue for an increased emphasis on encoding selectivity in theories of cognitive development.     

Visual perception of biological motion in newly hatched chicks as revealed by an imprinting procedure

Day-old chicks were exposed to point-light animation sequences depicting either a walking hen or a rotating cylinder. On a subsequent free-choice test (experiment 1) the chicks approached the novel stimulus, irrespective of this being the hen or the cylinder. In order to obtain equivalent local motion vectors, in experiments 2 and 3 newly hatched chicks were exposed either to a point-light animation sequence depicting a walking hen, or to a positionally scrambled walking hen (i.e. an animation in which exactly the same set of dots in motion as that employed for the walking hen was presented, but with spatially randomized starting positions). Chicks tested on day 1 (experiment 2) or on day 2 (i.e. after a period in the dark following exposure on day 1 (experiment 3)) proved able to discriminate the two animation sequences: males preferentially approached the novel stimulus, females the familiar one. These results indicate that discrimination was not based on local motion vectors, but rather on the temporally integrated motion sequence. Received: 18 August 1999 / Accepted after revision: 14 March 2000     

The Big Five personality traits and perceptions of touch to intimate and nonintimate body regions

This investigation tested whether (1) the Big Five personality traits contribute to favorable perceptions of touch from a relational partner, (2) participants’ sex or personality better predicted positive perceptions of touch, and (3) perceptions of touch vary as a function of relationship satisfaction. A total of 305 participants aged 18–69 years completed self-report measures of reactions to touch, personality, and relationship satisfaction. Results showed that agreeableness was a significant predictor of positive perceptions of touch to both intimate and nonintimate body regions. Openness to experience was also a significant predictor in positive perceptions of touch to nonintimate body regions. Overall, personality was a stronger predictor of positive perceptions of touch than either biological sex or relationship satisfaction with the toucher.