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511.
People find it difficult to enjoy their own thoughts when asked to do so, but what happens when they are asked to think about whatever they want? Do they find thinking more or less enjoyable? In the present studies, we show that people are more successful in enjoying their thoughts when instructed to do so. We present evidence in support of four reasons why this is: without instructions people do not realize how enjoyable it will be to think for pleasure, they do not realize how personally meaningful it will be to do so, they believe that thinking for pleasure will be effortful, and they believe it would be more worthwhile to engage in planning than to try to enjoy their thoughts. We discuss the practical implications of thinking for pleasure for promoting alternatives to the use of technology.  相似文献   
512.
Respect for the dignity and autonomy of patients has long been a fundamental principle of ethical decision making. As a practical matter, a primary way of maintaining this ethical standard is by obtaining an individual’s informed consent prior to intervening or collecting data. By giving individuals clear information about alternative treatments and potential risks and benefits, the practitioner tries to ensure that the patient can make an informed choice. However, there are cases in which those seeking informed consent have very different values and belief systems from those whose consent is being sought. In this article we explore such discrepancies using informed consent with Navajo clients as an example, illustrate potential challenges with case examples, and propose ways in which ethical dilemmas may be successfully navigated.  相似文献   
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Abstract— Intense hedonic states trigger psychological processes that are designed to attenuate them, and thus intense states may abate more quickly than mild states. Because people are unaware of these psychological processes, they may mistakenly expect intense states to last longer than mild ones. In Study 1, participants predicted that the more they initially disliked a transgressor, the longer their dislike would last. In Study 2, participants predicted that their dislike for a transgressor who hurt them a lot would last longer than their dislike for a transgressor who hurt them a little, but precisely the opposite was the case. In Study 3, participants predicted that their dislike for a transgressor who hurt them a lot would last longer than their dislike for a transgressor who hurt someone else a lot, but precisely the opposite was the case. These errors of prediction are discussed as instances of a more general phenomenon known as the region-β paradox.  相似文献   
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Rats with perirhinal cortex (PRC), hippocampal, or sham lesions were trained on a successive discrimination go/no-go task to examine recognition memory for an array of visual objects with varying interference among the objects in the array. Rats were trained to recognize a target array consisting of four particular objects that could be presented in any one of four possible configurations to cover baited food wells. If the four target objects were presented, the rat should displace each object to receive food. However, if a novel object replaced any one or more of the target objects, then the rat should withhold its response. The number of novel objects presented on nonrewarded trials varied from one to four. The fewer the number of novel objects in the array, the more interference the array shared with the target array, therefore increasing task difficulty. An increased number of novel objects should result in less interference with the target array and decreased task difficulty. Although accuracy was slightly lower in rats with hippocampal lesions compared with controls, the learning of the groups was not statistically different. In contrast, rats with PRC lesions were significantly impaired in learning compared with both control and hippocampal-lesioned rats. The results suggest that recognition memory for complex visual discriminations is affected by stimulus interference in rodents with PRC damage.  相似文献   
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During movement, the intrinsic muscle force-velocity property decreases the net force for the shortening muscle (agonist) and increases it for the lengthening muscle (antagonist). The authors present a quantitative analysis of the effect of that muscle property on activation and force output of the same muscle acting as agonist and antagonist in fast and medium speed goal-oriented movements. They compared biceps activation and force output when that muscle was the agonist in a series of elbow flexions and when it was the antagonist in a series of elbow extensions. They performed the same analysis for the lateral, long, and medial heads of the triceps muscle. Muscle EMG was about 2 times larger and the angular impulse developed by the modeled contractile torque was up to 3 times larger when the muscle or muscles acted as the agonist than when the same muscle or muscles acted as the antagonist in movements with similar kinematics. The large effect of the muscle force-velocity property strongly suggests that the neural controller must account for intrinsic muscle properties to generate movements with a commonly observed bell-shaped velocity profile.  相似文献   
519.
Western scrub-jays (Aphelocoma californica) cached perishable and nonperishable food items, which they could recover after both short and long retention intervals. When perishable items were always degraded at recovery, jays decreased the number of perishable items cached and increased their caching of nonperishable items, relative to a control group whose caches were always fresh at recovery. Jays reduced the number of nonperishable items cached, however, when highly preferred food items were degraded only after the long retention intervals. The findings are discussed in terms of the role of retrospective and prospective processes in the control of caching.  相似文献   
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The interrelationships of cerebellar and cerebral neural circuits in the eyeblink paradigm were explored with the controlled application of cortical spreading depression (CSD) and lidocaine in the New Zealand albino rabbit. The initial research focus was directed toward the involvement of the motor cortex in the conditioned eyeblink response. However, CSD timing and triangulation results indicate that other areas in the cerebral cortex, particularly the auditory cortex (acoustic conditioned stimulus), appear to be critical for the CSD effect on the eyeblink response. In summary: (1) CSD can be elicited, monitored, and timed and its side effects controlled in 97% of awake rabbits in the right and/or left cerebral hemisphere(s) during eyeblink conditioning. (2) The motor cortex appears to play little or no part in classical conditioning of the eyeblink in the rabbit in the delay paradigm. (3) Inactivating the auditory cortex with CSD or lidocaine temporarily impairs the conditioned response during the first 5 to 15 days of training, but has little effect past that point.  相似文献   
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