Does P3 Reflect Attentional or Memory Performances,or Cognition more Generally?

The study evaluated the off-line relationship of attention, memory and other cognitive performances with the auditory event-related potentials P3 (P300) and N2. The sample comprised 200 middle-aged construction workers. Verbal, visuomotor and memory tests were administered. Attentional domains were examined using CogniSpeed software. Slowed reaction times in the test of sustained attention (vigilance) were associated with delayed P3 latency (p < 0.001) and decreased P3 amplitude (p = 0.005), as well as with delayed N2 latency (p < 0.001). Visuomotor slowing in Digit Symbol was also related to delayed P3 latency (p = 0.030) and decreased P3 amplitude (p = 0.014). In contrast, mild cognitive impairment, short- and long-term memory, and concentrating or sharing attention with high working memory demands were not related to P3. The results suggest that P3 is linked to attentional performance with low working memory demands rather than to effortful working memory updating, retrieval from memory stores, or mild cognitive impairment.     

组织支持对工作压力的中介效应研究——基于知识型员工样本的实证分析

采用中介变量分析的一般范式,以知识型员工为研究样本,实证检验了组织支持在工作压力源与压力反应之间的中介效应。研究表明:组织支持在良性压力源(如任务要求、能力要求)与积极压力反应(如组织承诺、工作满意度、工作参与感)之间发挥显著的中介作用;在负性压力源(如人际冲突、组织结构问题、时间冲突)与积极和消极压力反应(如消极工作情绪)之间都发挥显著的缓冲作用。管理者在知识型员工压力管理过程中,应高度重视组织支持的中介缓冲作用。     

Ethological analysis of neuropeptides and psychotropic drugs: Effects on intraspecies aggression and sociability of isolated mice

The experiments on mice (under the condition of agonistic interactions) have shown increases and decreases in certain forms of species-specific behavior (aggression, defense, sociability) when synthetic peptides and psychotropic drugs were administered. MIF-1, TRH, and LH-RH (acute injections) enhance aggression in isolated mice while somatostatin reduces it. MIF–1 antagonizes the antiaggressive effects of haloperidol, muscimol, and morphine. ACTH 1–24 counteracts the action of diaze-pam on attacks and threats. Somatostatin reduces both aggression and sociability and that effect may be potentiated by diazepam. Neo-endorphin injected together with diazepam reduces aggression and enhances sociability. A combination of synthetic neuropeptides and well known psychotropic drugs (neuroleptics, tranquil-izers, and others) may be more effective for the control of aggression and sociability than the psychotropic drugs employed alone.     

The offensive nature of maternal aggression in mice: Effects of fluprazine hydrochloride

The phenylpiperazine fluprazine hydrochloride was used to test the hypothesis that maternal aggression in laboratory mice reflects offensive motivation. Lactating females (n = 8 per condition) tested for aggression following drug treatment (1.0 mg/kg and 5.0 mg/kg of fluprasine) were significantly less aggressive than saline controls according to all measures used. The findings support the hypothesis that maternal aggression is offensive in nature, and provide no evidence that maternal attack is a mixture of offensive and defensive tendencies.     

Prey-dependent effects of fluprazine hydrochloride on predatory aggression in northern grasshopper mice (Onychomys leucogaster) and rats (Rattus norvegicus)

Treatment with the phenylpiperazine DU 27716 (fluprazine hydrochloride) inhibited the predatory killing of albino mice by northern grasshopper mice (Onychomys leucogaster) and of frogs by rats. This treatment had no effect on cricket predation by grasshopper mice or worm predation by rats. The prey-specific effect of fluprazine did not seem to result from a decreased tendency to attack nor was its effect restricted to prey showing characteristic rodent defensive responses. Rather, the drug seemed to increase fearfulness when the prey exhibited vigorous defensive behavior. It is possible that increased fearfulness induced by treatment with this drug may also contribute to its antioffensive effect during conspecific encounters.     

Procedural learning across the lifespan: A systematic review with implications for atypical development

This systematic review aimed to investigate procedural learning across the lifespan in typical and atypical development. Procedural learning is essential for the development of everyday skills, including language and communication skills. Although procedural learning efficiency has been extensively studied, there is no consensus yet on potential procedural learning changes during development and ageing. Currently, three conflicting models regarding this trajectory exist: (1) a model of age invariance; (2a) a model with a peak in young adulthood; and (2b) a model with a plateau in childhood followed by a decline. The aims of this study were (1) to investigate this debate on procedural learning across the lifespan by systematically reviewing evidence for each model from studies using the serial reaction time task; and (2) to review procedural learning in autism spectrum disorder (ASD) and specific language impairment (SLI), two developmental disorders characterized by deficits in communication skills, in the light of these models. Our findings on typical development strongly support a model of age-related changes (Model 2a or 2b) and show that mixed findings regarding the developmental trajectory during childhood can be explained by methodological differences across studies. Applying these conclusions to systematic reviews of studies of ASD and SLI makes it clear that there is a strong need for the inclusion of multiple age groups in these clinical studies to model procedural learning in atypical development. Clinical implications of the findings are discussed. Future research should focus on the role of declarative learning in both typical and atypical development.     

Children's supernatural thinking as a signalling behaviour in early childhood

In this study, we analysed the reaction times of 137 college students when making decisions on pairs of hypothetical children verbalizing different types of vignettes and/or exhibiting different physical appearance (photographs of faces). Vignettes depicted immature and mature versions of both supernatural (e.g., ‘The sun's not out today because it's mad’ vs. ‘The sun's not out today because the clouds are blocking it’) and natural (‘I can remember all 20 cards!’ vs. ‘I can remember 6 or 7 cards’) explanations to ordinary phenomena. Photographs of children's faces were morphed with a physical appearance of approximately 4–7 years old or approximately 8–10 years old. In earlier research, immature supernatural thinking produced positive‐affect reactions from adults and older adolescents (14–18 years old) towards young children, with cognitive cues being more important than physical‐appearance cues in influencing adults’ judgements. Reaction times to make decisions varied for the Supernatural and Natural vignettes and for the immature and mature vignettes/faces, reflecting the differential cognitive effort adults used for making decisions about aspects of children's physical appearance and verbal expressions. The findings were interpreted in terms of the critical role that young children's immature supernatural thinking has on adults’ perception, analogous to the evolved role of immature physical features on adults’ perception of infants.     

Effects of cocaine on simple reaction times and sensory thresholds in baboons.

The effects of chronic, daily administration of cocaine on auditory and visual reaction times and thresholds were studied in baboons. Single intramuscular injections of cocaine hydrochloride (0.1 to 5.6 mg/kg) were given once daily for periods of 10 to 25 days, and were followed immediately by psychophysical tests designed to assess cocaine's effects on simple reaction times as on auditory and visual threshold functions. Consistent reductions in reaction times were frequently observed over the cocaine dose range of 0.32 to 1.0 mg/kg; at higher doses, either decreases or increases in reaction times were observed, depending upon the animal. Lowered reaction times generally occurred immediately following the 1st day's cocaine injection, and continued through all subsequent days during the dose administration period, suggesting little development of tolerance or sensitivity to these reaction-time effects. Reaction-time decreases showed a U-shaped dose-effect function. The greatest decreases in reaction times occurred from 0.32 to 1.0 mg/kg, and produced an average reaction-time decrease of 10 to 12%. Concurrently measured auditory and visual thresholds showed no systematic changes as a function of cocaine dose. Pausing was observed during performance of the psychophysical tasks, with the length of total session pause times being directly related to cocaine dose.     

Education and testing strategy for large-scale cystic fibrosis carrier screening

Population-based screening for cystic fibrosis carrier mutations presents a number of challenges for genetic counselors, owing primarily to the inability of current DNA testing technology to identify all possible mutations and the difficulty involved in conveying the concept of residual risk to those patients who test negative. To address these issues, we are conducting a pilot study, as part of a consortium established by the National Center for Human Genome Research, to explore the efficacy, acceptance, and psychosocial impact of various approaches to carrier screening in an ethnically diverse Southern California population. This article reports the patient instructional and screening strategies we developed in the initial phase of the project in order to optimize our chances of answering these questions and delivering this service on a large scale.     

Infants' fast saccades in the gap paradigm and development of visual attention

The saccadic reaction times (SRTs) in the overlap, no-overlap, and gap conditions of 2.5- to 12-month-old infants and adults were measured. In the overlap condition, the SRTs of younger infants were over 600 ms longer than those of older infants, whereas the SRTs in the gap condition of the younger infants were 300–350 ms, much faster than reported hitherto, and were shortened only by about 100 ms. The results indicate that the oculo-motor system and attention process for disengagement in the gap condition mature earlier than the attention process for disengagement in the overlap condition.