Neuropsychological Functioning Associated with High-Altitude Exposure

This article focuses on neuropsychological functioning at moderate, high, and extreme altitude. This article summarizes the available literature on respiratory, circulatory, and brain determinants on adaptation to hypoxia that are hypothesized to be responsible for neuropsychological impairment due to altitude. Effects on sleep are also described. At central level, periventricular focal damages (leuko-araiosis) and cortical atrophy have been observed. Frontal lobe and middle temporal lobe alterations are also presumed. A review is provided regarding the effects on psychomotor performance, perception, learning, memory, language, cognitive flexibility, and metamemory. Increase of reaction time and latency of P300 are observed. Reduced thresholds of tact, smell, pain, and taste, together with somesthetic illusions and visual hallucinations have been reported. Impairment in codification and short-term memory are especially noticeable above 6,000 m. Alterations in accuracy and motor speed are identified at lower altitudes. Deficits in verbal fluency, language production, cognitive fluency, and metamemory are also detected. The moderating effects of personality variables over the above-mentioned processes are discussed. Finally, methodological flaws found in the literature are detailed and some applied proposals are suggested.     

Reinforcement magnitude and responding during treatment with differential reinforcement

Basic findings indicate that the amount or magnitude of reinforcement can influence free-operant responding prior to and during extinction. In this study, the relation between reinforcement magnitude and adaptive behavior was evaluated with 3 children as part of treatment with differential reinforcement. In the first experiment, a communicative response was shaped and maintained by the same reinforcer that was found to maintain problem behavior. Two reinforcement magnitudes (20-s or 60-s access to toys or escape from demands) were compared and found to be associated with similar levels of resistance to extinction. The relation between reinforcement magnitude and response maintenance was further evaluated in the second experiment by exposing the communicative response to 20-s or 300-s access to toys or escape. Results for 2 participants suggested that this factor may alter the duration of postreinforcement pauses.     

重复性急性应激对攻击行为的影响及调控机制

关于急性应激对攻击行为的影响, 现有研究多集中于单次急性应激情境下。然而, 相比单次急性应激, 对重复暴露于同一应激源的研究更能反映人们在现实生活中经历的应激事件。与单次应激不同, 重复性急性应激与应激适应有关, 能够节省资源, 具有很强的进化和适应意义, 但目前关于重复性急性应激对攻击行为的影响却知之甚少。鉴于此, 研究运用事件电位相关技术、鼻喷催产素和催产素受体基因型分析方法, 探讨重复性急性应激对攻击行为的影响及内部机制, 并进一步探讨通过内部和外部调控重复性急性应激反应后攻击行为的变化。     

Post-stroke depression as a predictor of caregivers burden of acute ischemic stroke patients in China

Our aim was to explore the independent attribution of Post-stroke depression (PSD) to caregiver burden of acute ischemic stroke patients. A cross-sectional survey was performed with 271 acute ischemic stroke patients in the Huai-He Hospital and First People’s Hospital of Kaifeng City in China. PSD was assessed by Self-rating Depressive Scale, and caregiver burden was assessed by Zarit Caregiver Burden Interview. Clustered logistic regression was applied to identify the impact of PSD on caregiver burden. As results, female patients, normal muscle strength and PSD were associated with caregiver burden. PSD correlated with an independent influence of 17.2% on the risk of caregiver burden, The independent influence of PSD on caregiver burden was smaller than that of social-demographics of caregivers and clinical factors of stroke patients This study suggests that PSD may have a modest influence on caregiver burden.     

Brain-derived neurotrophic factor Val66met polymorphism and plasma levels in road traffic accident survivors

Background: Alterations in brain-derived neurotrophic factor (BDNF) expression and release may play a role in the pathogenesis of post-traumatic stress disorder (PTSD). Design: This study evaluated road traffic accident (RTA) survivors to determine whether PTSD and trauma-related factors were associated with plasma BDNF levels and BDNF Val66Met carrier status following RTA exposure. Methods: One hundred and twenty-three RTA survivors (mean age 33.2 years, SD?=?10.6 years; 56.9% male) were assessed 10 (SD?=?4.9) days after RTA exposure. Acute stress disorder (ASD), as assessed with the Acute Stress Disorder Scale, was present in 50 (42.0%) of the participants. Plasma BDNF levels were measured with enzyme-linked immunosorbent assay and BDNF Val66Met genotyping was performed. PTSD, as assessed with the Clinician-Administered PTSD Scale, was present in 10 (10.8%) participants at 6 months follow-up. Results: Neither BDNF Val66Met genotype nor plasma BDNF was significantly associated with the presence or severity of ASD or PTSD. Plasma BDNF levels were, however, significantly correlated with the lifetime number of trauma exposures. Conclusions: In RTA survivors, plasma BDNF levels increased with increasing number of prior trauma exposures. Plasma BDNF may, therefore, be a marker of trauma load.     

急性疼痛与慢性疼痛对奖赏加工的影响及神经机制

疼痛和奖赏能够为个体提供不同的行为动机和主观价值体验,寻求奖赏和避免疼痛对于生存都很重要。疼痛可划分为急性疼痛和慢性疼痛,奖赏可区分为预期阶段的动机成分和体验阶段的享乐成分。奖赏对疼痛的抑制作用已经被广泛证实,但关于疼痛对奖赏的影响,目前的研究结果并不一致。因此需要进一步区分并探究急性疼痛与慢性疼痛对奖赏加工不同阶段的影响,分析两种疼痛对奖赏加工产生不一致影响的现象。这种现象出现的原因可能与急性疼痛向慢性疼痛转变过程中出现的奖赏加工能力缺陷有关。未来可以考虑从改善奖赏加工能力缺陷的角度进行检测和治疗,提前预防急性疼痛向慢性疼痛转变。     

急性呼吸窘迫综合征肺泡塌陷与肺复张的意义

大量肺泡塌陷是急性呼吸窘迫综合征(ARDS)病理生理改变的基础,可导致顽固性低氧血症、肺泡表面活性物质丢失、呼气气流受限、去复张性肺损伤、肺部感染和生物性肺损伤。积极的实施肺开放策略,实现塌陷肺泡的复张具有重要的临床意义。肺复张导致肺泡过度膨胀、循环干扰,以及肺泡难以复张因素的存在,使肺泡完全复张可能并不必要。在避免肺泡塌陷危害与肺复张的局限性之间寻求平衡,才能使肺复张确立其在ARDS治疗中的恰当地位。     

小儿重症肺炎的诊治策略

肺炎是儿童常见的呼吸道疾病,小儿重症肺炎及其导致的并发症特别全身炎症反应综合征和多脏器功能衰竭是严重威胁儿童健康和生命的重要原因。随着基础医学和临床医学的发展,人们的认识逐渐深入,防治水平也取得重要进展。但病原学的变迁,不恰当的临床监测和干预仍然影响着人们对该病的正确认识和处理。运用哲学的辩证思维来探讨小儿重症肺炎诊治中的若干问题,将为儿科临床工作提供新的指导。     

急性心肌梗死中医治疗的两点策略——附临床资料回顾性分析

急性心肌梗死(AMI)是临床常见的急重症,现代医学已在循证医学基础上建立了诊疗指南,为临床诊治决策提供依据。相比而言,以辨证论治为特色的中医药缺乏循证依据。对AMI诊治过程中如何发挥中医药治疗的价值,认为不能停留在传统的概念上,应选择正确治疗策略,提高疗效。