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本实验探讨了影响深度觉及距离判断的有关因素。实验分三部分:一、双眼正视(0°)和双眼斜视(45°)条件的深度觉辨别实验;二、双眼正视(0°)条件下不同距离相对判断实验;三、双眼斜视(45°)条件下的相对距离判断实验。实验结果表明:在双眼正视条件下(0°),深度觉辨别最准确,双眼斜视(45°)条件下,误差值明显增加,而单眼正视条件下,误差值最大。双眼斜视(45°)条件下的相对距离判断的误差值明显较之双眼正视(0°)条件下的为大。对2/4的相对距离判断的准确性均较之对1/4和3/4的距离为高。在双眼斜视条件下,眼肌调节发生变化,睫状肌紧张度增加,视觉易于疲劳可能是造成深度觉及距离判断准确性降低的主要原因。  相似文献   
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Previous research among university students has identified four classes of assertive behavior, namely, Directiveness, Social Assertiveness, Defense of One's Rights and Interests and Independence. Scores on the Lorr and More (1980) Assertiveness Inventory, obtained from a general population sample, were subjected to Varimax rotatio. Results revealed only three classes of assertiveness. It is argued that Directiveness may be inferred from various forms of assertiveness, rather than being a separate and distinct class of assertive behavior.  相似文献   
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本工作是在前一工作的基础上,进一步研究分别电损毁有关回路的乳头体、隔区,对以糖精水为条件刺激。氯化锂腹腔注射引起中毒作为非条件刺激的条件性糖精厌恶痕迹的形成和保存的影响。结果表明,无论是损毁乳头体,或者隔区,对条件性糖精厌恶痕迹的形成和保存均无影响。说明在本实验条件下,这种条件性味觉痕迹的形成与保存,不依赖边缘系统的乳头体、海马、隔区这些回路的参与,这就进一步说明味觉信号的记忆确有其不同于视、听觉信号的记忆的机制的。  相似文献   
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本文观察了在成年后进行群体隔离的大白鼠与群居鼠在摄食、饮水、睡眠等方面的行为差异。着重观察了社会应激对成年后进行群体隔离的动物的行为的影响,以研究群体隔离时动物的年龄与过去生活经验是不是动物在社会应激时发生的行为改变的关键因素。 结果表明:群居与隔离两种环境对动物摄食、饮水和体重无明显影响,但隔离动物睡眠时间较群居动物短。即使在成年后进行群体隔离、社会应激对隔离动物的摄食、饮水、睡眠和攻击性行为的影响也比群居组明显。但进行群体隔离时动物的年龄和隔离前有较长时间的群居生活经验可大大减轻社会应激时行为反应的强度,也可使适应过程发生得快些。这说明早期环境和过去生活经验的重要性。社会应激影响饮水和摄食的方式随年龄而改变,年龄较大的群居鼠对社会应激的适应可能比年龄较轻的群居鼠差。  相似文献   
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Previous research has evaluated the effects of prompt rates on the rate of communicative behavior. More recent research has suggested that dense prompting can result in communicative behavior that is more resistant to change. However, existing research has not considered the impact that higher response rates had on reinforcement rate, a variable known to impact response persistence. The current study systematically replicated previous research by evaluating communicative responding in contexts associated with dense- and lean-prompt schedules and extended existing research by (a) holding reinforcement rates similar across the two prompting schedules (lean and dense), and (b) evaluating the persistence of communicative responding in the contexts associated with each prompting schedule. The results for Experiment 1 clearly replicated and extended previous research. The results for Experiment 2 were equivocal and suggested that previous reinforcement history and response class size impacted outcomes.  相似文献   
48.
Animal Cognition - Exploring new and unfamiliar environments is critical for survival, providing information on food, shelter, mates, and sources of danger. The open field paradigm is commonly used...  相似文献   
49.
Raven's Advanced Progressive Matrices (APM) Set I is a validated and brief test of fluid intelligence, ideal for use in busy clinical settings. However, there is a dearth of normative data allowing an accurate interpretation of APM scores. To address this, we present normative data from across the adult lifespan (18–89 years) for the APM Set I. Data are presented in five age cohorts (total N = 352), including two older adult cohorts (65–79 years and 80–89 years), which allows age-standardized assessment. We also present data from a validated measure of premorbid intellectual ability, which was absent from previous standardizations of longer forms of the APM. In line with previous findings, a striking age-related decline was noted, beginning relatively early in adulthood and most marked amongst lower-scoring individuals. Older adults did not demonstrate difficulty with specific test items or make an increased proportion of specific errors. Sex was not a significant predictor of performance. The data set is of particular use in the neuropsychological assessment of older adults, given the known susceptibility of fluid intelligence to both the effects of normal ageing and acquired brain injury in older age. The results are discussed in light of theories of neurological ageing.  相似文献   
50.
The COVID-19 pandemic brought new attention to the issues of food insecurity faced by individuals throughout the United States, a stressor exacerbated by disruptions to work status and supply chains. The burden of food insecurity likely carries consequences for whether individuals feel capable of pursuing their broad goals and life engagements; put differently, food insecurity may pose a threat to people perceiving a sense of purpose in life. The current study tested this claim across three samples taken during 2020 (n = 2009), 2021 (n = 1666), and 2022 (n = 1975). Participants completed inventories for perceived food insecurity, sense of purpose, depressive symptoms, and anxiety, among other measures. Results found consistent negative associations between food insecurity and sense of purpose across all three samples. In addition, food insecurity moderated associations between sense of purpose and depressive or anxiety symptoms. Sense of purpose was more strongly negatively associated with depressive and anxiety symptoms for those participants who reported no food insecurity. That said, sense of purpose remained negatively associated with psychological distress even among those reporting food insecurity.  相似文献   
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