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991.
992.
When readers need to go beyond the straightforward compositional meaning of a sentence (i.e., when enriched composition is required), costly additional processing is the norm. However, this conclusion is based entirely on research that has looked at enriched composition between two phrases or within the verb phrase (e.g., the verb and its complement in . . . started the book . . .) where there is a discrepancy between the semantic expectations of the verb and the semantics of the noun. We carried out an eye-tracking experiment investigating enriched composition within a single noun phrase, as in the difficult mountain. As compared with adjective–noun phrases that allow a straightforward compositional interpretation (the difficult exercise), the coerced phrases were more difficult to process. These results indicate that coercion effects can be found in the absence of a typing violation and within a single noun phrase.  相似文献   
993.
The defensive withdrawal reflexes of Aplysia californica have provided powerful behavioral systems for studying the cellular and molecular basis of memory formation. Among these reflexes the tail-elicited tail withdrawal reflex (T-TWR) has been especially useful. In vitro studies examining the monosynaptic circuit for the T-TWR, the tail sensory-motor (SN-MN) synapses, have identified the induction requirements and molecular basis of different temporal phases of synaptic facilitation that underlie sensitization in this system. They have also permitted more recent studies elucidating the role of synaptic and nuclear signaling during synaptic facilitation. Here we report the development of a novel, compartmentalized semi-intact T-TWR preparation that allows examination of the unique contributions of processing in the SN somatic compartment (the pleural ganglion) and the SN-MN synaptic compartment (the pedal ganglion) during the induction of sensitization. Using this preparation we find that the T-TWR is mediated entirely by central connections in the synaptic compartment. Moreover, the reflex is stably expressed for at least 24 h, and can be modified by tail shocks that induce sensitization across multiple temporal domains, as well as direct application of the modulatory neurotransmitter serotonin. This preparation now provides an experimentally powerful system in which to directly examine the unique and combined roles of synaptic and nuclear signaling in different temporal domains of memory formation.  相似文献   
994.
Considerable neuroimaging research in humans indicates that the frontal pole cortex (FPC), also known as Brodmann area 10, contributes to many aspects of cognition. Despite these findings, however, its fundamental function and mechanism remain unclear. Recent neurophysiological results from the FPC of monkeys have implications about both. Neurons in the FPC seem to encode chosen goals at feedback time and nothing else. Goals, the places and objects that serve as targets for action, come in many forms and arise from many cognitive processes. The FPC's signal, although surprisingly simple for neurons at the apex of a prefrontal hierarchy, could promote learning about which kinds of goals and goal-generating processes produce particular costs and benefits, thereby improving future choices.  相似文献   
995.
Movement organization of cricket batters' actions was analyzed under three distinct experimental task constraints: a representative condition of a practice context in which the batters batted against a "live" bowler, a ball projection machine, and a near life-size video simulation of a bowler. Results showed that each distinct set of task constraints led to significant variations in the patterns of movement control. Removal of advanced information sources from a bowler's actions when the batters faced the ball projection machine caused significant delays in movement initiation, resulting in reduced peak bat swing velocities and a reduction in the quality of bat-ball contact, when compared with batting against a "live" bowler. When responding to a two-dimensional video simulation, batters were able to use information from the bowlers' action, enabling fidelity of initial behavioral responses consistent with the task of batting against a "live" bowler. However, without interceptive task requirements or actual ball flight information, significant variations in downswing initiation timing and peak bat velocities were demonstrated. Findings stress the need for representative experimental and learning designs in fast ball sports for developing performers.  相似文献   
996.
The current research examined the predictions that short-term memory models generate for the phonological similarity effect, when similarity was defined in different ways. Three serial recall experiments with consonant–vowel–consonant (CVC) nonwords are reported, where the position of the phonemes that list items shared was manipulated (i.e., shared vowel and final consonant [_VC; Experiment 1], initial consonant and vowel [CV_; Experiment 2], or the two consonants [C_C; Experiment 3]. The results show that the position of common phonemes in nonwords has differential effects on order and item information. The findings are discussed in relation to previous research into the effect of phonemic similarity on nonword recall, and modifications to current short-term memory models are proposed.  相似文献   
997.
Numerous reaction time studies have suggested that age-related declines in cognitive function might be ameliorated by lifestyles involving aerobic activity or by interventionist programmes of aerobic exercise. These studies are far from conclusive, however, reflecting a failure to factor out cognitive from sensory and motor processes. Following a critical review of the literature, we report on recent developments that differentiate cognitive processes involving executive vs non-executive control, the former being associated with frontal lobe function. Three key studies suggest that aerobic exercise primarily improves executive control.  相似文献   
998.
In the present study, we investigated the influence of cognitive factors on eye-movement behaviors in reading. Participants performed two tasks: a normal-reading task, as well as a mindless-reading task in which letters were replaced with unreadable block shapes. This mindless-reading task served as an oculomotor control condition, simulating the visual aspects of reading but removing higher-level linguistic processing. Fixation durations, word skipping, and some regressions were influenced by cognitive factors, whereas eye movements within words appeared to be less open to cognitive control. Implications for models of eye-movement control in reading are discussed.  相似文献   
999.
Dogs were conditioned to an anxiety response characterized by an increase in heart rate upon presentation of a musical tone. Meprobamate, chlordiazepoxide and diazepam effectively prevented the cardiac conditioned response. Phenobarbital and chlorpromazine were less effective. Amphetamine, 1.5 orally, also blocked the cardiac conditioned response. Atropine, meperidine, caffeine, imipramine and -methyl-dopa had no effect on the cardiac conditioned response. Morphine and methyl phenidate were clearly active only in doses producing marked side effects. Ethanol in relatively small doses was mildly effective.  相似文献   
1000.
Frequently, people learn to classify instances of a concept and later learn additional information about the concept. What is the effect of this later learning on the original classification? In five experiments, this issue was investigated with a common classification paradigm in which symptom sets were classified into disease categories. After learning to classify these sets, the subjects learned to use the category to decide what treatment should be given for a symptom set. The symptoms that were important for the treatments were later classified by disease more accurately and were generated earlier from the disease name. However, this effect occurred only if the category representation was activated during the learning of the treatments. Thus, later learning about a particular use of the concept can sometimes affect the original classification.  相似文献   
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