儿童内包量概念发展的实验研究

以2～5年级学生为被试．系统探讨了儿童速度、浓度内包量概念的发展。研究发现：(1)儿童的内包量概念发展要经历四个阶段;(2)儿童速度概念的形成早于其浓度概念的形成;(3)凋整任务在儿童解决速度内包量问题中优于比较任务;(4)儿童解决内包量概念问题的策略经历从单维向双维、从比差的加法法则向乘法法则的转变。     

Age-related changes of phasic heart rate responses to affective pictures

This study examined age differences in phasic heart rate in response to neutral, negative and positive pictures. Heart rate changes and subjective ratings were analyzed in 22 middle-aged (40-55 years) and 30 older (56-78 years) participants. The effects of valence on the HR pattern across time were similar to that obtained by Bradley and co-workers. Conversely to previous studies, we did not report any age-related reduction in cardiac reactivity. Instead, when viewing positive pictures, the triphasic wave form appeared in the group of older adults, but for younger participants, it was replaced by a sustained deceleration. These results were interpreted in the light of the socioemotional selectivity theory.     

Children's understanding of directed motion events in an imitation choice task

We investigated children’s understanding of directed motion events using an imitation choice paradigm. A total of 34 children (mean age 33 months) watched a model act out an event containing a manner of motion (hopping or sliding), a motion path (up or down a ramp), and a goal (in or on a bowl). On the children’s apparatus, the locations of the goal objects were different from the model so that the children needed to choose whether to imitate the path or the goal of the model’s event. Children’s choice of which component to imitate, therefore, reflects how they prioritize these event components. Most children showed no bias to imitate the goal of the event and, instead, preferred to imitate the model’s path at the expense of the model’s goal. However, children who spontaneously played with the goal objects during a free play session showed a diminished path preference, choosing to imitate path and goal components equally often. We suggest that children’s prioritization of information within an event depends on how that information is structured within the event itself.     

A family history of psychopathology modifies the decrement in cognitive control among patients with HIV/AIDS

The present study was designed to evaluate the effect of HIV/AIDS on cognitive control and to determine if the effect is modified by familial risk for either alcohol or mood disorders. Sixty HIV-1 seropositive and 75 seronegative volunteers were assigned to four subgroups defined by the crossing of a diagnosis of alcohol dependence in the biological father with diagnoses of either major depressive disorder or bipolar disorder in the biological mother. Cognitive control was evaluated during a task in which subjects were asked, on occasion, to inhibit the impulse to respond in the same physical direction as the stimulus and instead respond in the opposite direction. Event related brain potentials and measures of task performance were recorded. The task evoked a negative shift in a late slow potential (SP) as well as an increment in reaction time when cognitive control was challenged. An important finding was an interaction between trial type, HIV/AIDS, and family history: HIV/AIDS and family history each attenuated the negative shift in the SP to such a degree that no further attenuation could be accomplished by the other. The effects of familial risk for alcohol versus mood disorders were equivalent. In conclusion, the absence of change in a late slow potential following a challenge to cognitive control may represent a marker of familial risk for both externalizing and internalizing disorders. The effects of familial risk on this slow potential are sufficiently robust as to attenuate the effects of HIV/AIDS on the probable generators of the response: the anterior cingulate and prefrontal cortex.     

Using heart rate as a physical activity metric

Physical activity (PA) is critical for a healthy lifestyle. The current study assessed heart rate (HR) as a primary measure of moderate and vigorous PA with four typically developing children. First, individualized HR assessments were conducted to determine moderate and vigorous HR zones. Next, participants engaged in various exercises at a local YMCA facility (i.e., biking, elliptical, basketball, and exergame boxing) to determine how HR during these activities aligned with their individualized HR zones. During exercise bouts, HR was typically above moderate, but below vigorous HR zones for all participants. Additionally, exercises that restricted range of motion (i.e., biking and elliptical) engendered generally lower HR than exercises with greater range of motion. Vocal instructions to exercise at vigorous levels were effective at increasing HR to vigorous levels for one participant. The advantages of using HR as a metric of PA during assessment and intervention are discussed.     

Response rate correlates with indifference points in a delay‐discounting procedure

To study how effort affects reward value, we replicated Fortes, Vasconcelos and Machado's (2015) study using an adjusting‐delay task. Nine pigeons chose between a standard alternative that gave access to 4 s of food, after a 10 s delay, and an adjusting‐delay alternative that gave access to 12 s of food after a delay that changed dynamically with the pigeons' choices, decreasing when they preferred the standard alternative, and increasing when they preferred the adjusting alternative. The delay value at which preference stabilized defined the indifference point, a measure of reward value. To manipulate effort across phases, we varied the response rate required during the delay of the standard alternative. Results showed that a) the indifference point increased in the higher‐response‐rate phases, suggesting that reward value decreased with effort, and b) in the higher‐response‐rate phases, response rate in the standard alternative was linearly related to the indifference point. We advance several conceptions of how effort may change perceived delay or amount and thereby affect reward value.     

Young adult couples’ behavioral and physiological responses to the infant simulator: A preliminary illustration of coparenting

This exploratory application of the infant simulator with two couples is designed to illustrate individual reactivity and coparenting behaviors in young couples in serious relationships who do not yet have children. A 35-min protocol with standardized onsets and offsets of inconsolable baby cries was used to capture partner’s individual behavioral and physiological responses as well as the couple’s joint efforts to soothe the crying baby. Task feasibility was demonstrated by couples’ persistent and wide-ranging efforts to calm the baby including rocking, feeding, changing, talking to the baby, and singing. Within-person fluctuations in ongoing heart rate (HR) and electrodermal activity (EDA) through the protocol suggested evidence of heightened physiological reactivity during baby crying compared to silence. During bouts of crying, higher HR also was evidenced when participants took the lead in caregiving as contrasted with assisting or busying themselves in another task. Behavioral observations indicated that this task elicited examples of coparenting behaviors including cooperation, support, undermining, and negotiating the division of labor. These preliminary pilot data demonstrate the potential of infant simulator paradigms with couples who are not yet pregnant but envision being future parents, and set the stage for future research to identify how individual and couple characteristics might impact reactions to shared baby caregiving.     

长沙市新型农村合作医疗现状与对策研究

新型农村合作医疗制度是我国农民的基本医疗保障制度,长沙市自2003开始试点,2006年全面推行,农民参合率达到84．6％,有效保障了农民能享有基本医疗卫生保健服务。通过对长沙2006年四县五区的新型农村合作医疗工作进行调查,分析了新型农村合作医疗存在的问题,提出了进一步改进的政策方案。     

Further analysis of the matching law to describe two- and three-point shot allocation by professional basketball players

The matching law was used to analyze whether the proportion of shots taken from two- or three-point range would match the proportional reinforcement rates produced by those shots when the reinforcement rate of three-point shooting was changed. Rule changes in 1994 and 1997 altered the distance of the three-point line in the National Basketball Association, which created a quasiexperimental reversal design, thereby naturally changing three-point reinforcement rates. The present data partially confirmed predictions made by the matching law, in that increases in the relative rate of three-point shots attempted corresponded to increases in the relative rate of three-point shots made.     

Frontal brain electrical activity (EEG) and heart rate in response to affective infant-directed (ID) speech in 9-month-old infants

Many studies have shown that infants prefer infant-directed (ID) speech to adult-directed (AD) speech. ID speech functions to aid language learning, obtain and/or maintain an infant's attention, and create emotional communication between the infant and caregiver. We examined psychophysiological responses to ID speech that varied in affective content (i.e., love/comfort, surprise, fear) in a group of typically developing 9-month-old infants. Regional EEG and heart rate were collected continuously during stimulus presentation. We found the pattern of overall frontal EEG power was linearly related to affective intensity of the ID speech, such that EEG power was greatest in response to fear, than surprise than love/comfort; this linear pattern was specific to the frontal region. We also noted that heart rate decelerated to ID speech independent of affective content. As well, infants who were reported by their mothers as temperamentally distressed tended to exhibit greater relative right frontal EEG activity during baseline and in response to affective ID speech, consistent with previous work with visual stimuli and extending it to the auditory modality. Findings are discussed in terms of how increases in frontal EEG power in response to different affective intensity may reflect the cognitive aspects of emotional processing across sensory domains in infancy.