Infant attention to intentional action predicts preschool theory of mind

This research examines whether there are continuities between infant social attention and later theory of mind. Forty-five children were studied as infants and then again as 4-year-olds. Measures of infant social attention (decrement of attention during habituation to displays of intentional action) significantly predicted later theory of mind (false-belief understanding). Possibly, this longitudinal association could have been explained by more general developments in IQ, verbal competence, or executive function (rather than continuities in the realm of social cognition). However, the association remained significant and undiminished even when IQ, verbal competence, and executive function were controlled. The findings thus provide strong support for an important continuity in social cognition separable from continuities in more general information processing.     

Evidence for an explanation advantage in naïve biological reasoning

The present studies compare young children's explanations and predictions for the biological phenomenon of contamination. In Study 1, 36 preschoolers and 24 adults heard vignettes concerning contamination, and were asked either to make a prediction or to provide an explanation. Even 3-year-olds readily supplied contamination-based explanations, and most children mentioned an unseen mechanism (germs, contact through bodily fluids). Moreover, unlike adults who performed at ceiling across both explanation and prediction tasks, children were significantly more accurate with their explanations than their predictions. In Study 2, we varied the strength of cues regarding the desirability of the contaminated substance (N=24 preschoolers). Although desirability affected responses, for both levels of desirability participants were significantly more accurate on explanation than prediction questions. Altogether, these studies demonstrate a significant "explanation advantage" for children's reasoning in the domain of everyday biology.     

纵向再探学前儿童心理理论发展模式

本文作者前不久完成的一项横断设计研究中, 以自编的心理理论量表测查比较了中美两国3~5岁儿童的有关发展。量表包括五项任务: (1) 不同的愿望; (2) 知与不知; (3) 不同的信念; (4) 内容错误信念和 (5) 伪装的情绪。研究发现两种不同文化群体儿童对上述任务的理解均表现出稳定一致的发展次序, 两者的次序大致相同但具有重要差别: 我国儿童的理解次序如从易到难排列如上所列, 这一次序与美国儿童的差别在于我国儿童先理解“知与不知”, 然后是“不同的信念”, 而美国儿童则恰好相反。这一研究结果对了解不同文化儿童心理理论的发展次序是十分有意义的, 但问题是经由横断设计的量表研究所确立的发展次序能否准确地描述个体儿童的纵向进展呢? 为此本研究使用了相同的测量工具对参加过横断研究的北京3岁儿童(时间1)在他们4岁(时间2)和5岁(时间3)时进行了焦点追踪研究。研究结果表明, 随着测查时间的 延伸, 个体儿童的作业成绩不仅逐步提高, 而且这种提高符合量表任务的发展次序。通过应用格特曼(Guttman)和雷氏(Rasch)测量模型对这一结果的分析, 再一次证实我国个体儿童的有关发展次序与欧美文化儿童的发展次序大致相同并且有重要的差别。本研究的结果不仅能为横断研究中个别差异的研究提供有用的工具, 而且深化了人们对心理理论发展机制的认识, 即把心理理论的发展看作是在一定的文化环境影响下不断扩展和深化的概念建构过程。但对这一推论仍有待进一步证实。     

Effects of tobacco smoking, schizotypy and number of pre-exposures on latent inhibition in healthy subjects

Latent inhibition is a slowing of learning about a stimulus that when previously experienced had no consequences. This study investigated the effects of tobacco smoking and personality traits on a latent inhibition task. Two-hundred and five healthy adults performed an auditory masking task during which half of them were pre-exposed to bursts of white noise. All subjects were then asked to detect an association of the white noise with a change on a computer screen. Subjects who had heard the white noises before were slower to learn the association than subjects who had not, i.e. they showed latent inhibition. Latent inhibition was stronger when subjects were pre-exposed to 10 rather than 6 bursts of white noise. Latent inhibition was reduced in subjects who smoked tobacco and in non-smoking subjects who scored highly on a schizotypy questionnaire. These two effects were independent. We conclude that tobacco smoking should be taken into account in interpreting the results of human latent inhibition studies.     

Theory of mind: The state of the art*

Abstract

In this article, I reflect on theory of mind as a field (ToM), how it has developed over the years, and focally on the state of current research and theory. Having begun with preschoolers’ understanding of beliefs and desires, the field now includes research from infancy through late life, contributions and contributors from around the world, research on behavior, conversation, neural correlates, gene-environment contributions, evolution, and the social-behavioral antecedents and consequences of the unfolding trajectories of ToM understanding. Several topics in particular portray the current state of the art and my sense of where theory-of-mind research is likely to head in the near future: progressions of theory of mind achievement; cultural experiences plus experiential influences that shape developmental trajectories; developmental cognitive neuroscience; infant ToM insights; research on ToM developments beyond preschool, including children’s increasing interest in and wrestling with extraordinary minds, such as those of God and super-heroes.     

Influence of lateral motion transfer on sleep.

This study examined the effects of motion of an artificial bed partner on the sleep of a real subject on the same mattress. A 240-lb eight-sided cylindrical roller served as the artificial bed partner. The roller was placed on one side of a king-size mattress and a normal adult slept on the other half. On experimental nights, the roller intermittently rocked back and forth for brief periods of time which in aggregate represented approximately 13% of total sleep time. On control nights, the roller was stationary. After an adaptation night in the laboratory, subjects spent two more nights in the sleep laboratory. The order of Roller On and Roller Off nights was random. 24 subjects were randomly assigned to sleep on the three surfaces. The three mattresses used in the study had different construction designs and in turn variable properties of motion transfer. Sleep variables were measured objectively by nocturnal polysomnography and subjectively by a postsleep questionnaire. Analysis of the data indicated that motion transferred laterally across a mattress was associated with a significant increase in Stage 1 sleep, and a significant decrease in Stage 3/4 sleep. Over-all, sleep efficiency, number of awakenings, and wakefulness after sleep onset did not show significant changes from control to experimental nights. The amount of change in sleep architecture, however, was more notable on the mattresses which transferred more motion. An implication of these findings is that motion transferred across the surface of a mattress, by lightening the depth of the sleep and thereby decreasing the auditory arousal threshold, can increase the potential for sleep disruption from environmental stimuli such as noise.     

Cortical neuroanatomical correlates of behavioral deficits produced by lesion of the basal forebrain in rats

Morphological changes in the frontoparietal cortex were assessed in rats that exhibited deficits in a go/no go alternation task due to electrolytic lesion of the basal forebrain. Cortical area, laminar thickness, neuronal density, and soma area were examined in frontal, hindlimb, forelimb, and parietal areas of the cortex. Quantitative morphological analysis of the frontoparietal cortex in lesioned rats revealed a decrease in laminar thickness due to reduced soma size in particular cortical laminae. Neuronal density was not affected. These effects were present in all cortical areas examined and most pronounced in laminae II-III. Similar morphological changes were observed in the same cortical areas following lesions of the basal forebrain made with ibotenic acid, allowing a discrimination of lesion effects from those induced by damage to fibers of passage or differential behavioral testing. Lesions of the basal forebrain have previously been shown to produce both behavioral deficits and changes in cortical cholinergic activity. The cortical morphological changes observed in the present study following basal forebrain lesion provide further evidence for the importance of ascending cholinergic inputs to the cortex and their role in learning and memory.