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1.
This experiment tested for age-linked asymmetries predicted under Node Structure theory (NST; D. G. MacKay & D. M. Burke, 1990) between detecting versus retrieving orthographic information. Older adults detected that briefly presented words were correctly spelled (e.g., endeavor) or misspelled (e.g., endeavuor) as readily as did young adults. However, they were less able than young adults to retrieve the correctly and incorrectly spelled words that they had seen. These age-linked asymmetries were not due to educational factors, stimulus characteristics, sensory-level factors, task complexity, floor or ceiling effects, general slowing, or cohort-related activities, but they were consistent with NST predictions and with similar asymmetries in a wide range of other studies. By contrast, repetition deficits in detecting and retrieving repeated- versus unrepeated-letter misspellings (e.g., elderdly vs. elderkly) were symmetrical or equivalent in magnitude for young and older adults. Implications for a wide range of theories of cognitive aging and of repetition deficits are discussed.  相似文献   

2.
There is considerable evidence to document the case that the preferred hand is demonstrably superior for a number of manual tasks, although the mechanisms underlying this effect are less clear. Two perspectives have been dominant; one that emphasizes differential efficiency of feedback processing and one that suggests that asymmetries are a function of increased variability of output for the nonpreferred hand. This review considers the mediating effect of the complexity of the visual space in which aimed movements occur. Some inconsistencies may be resolved by noting the superiority of the right cerebral hemisphere for manipulation of spatial relationships. A multilevel, transactional perspective, which must then be adopted, may accommodate both feedback processing and motor output variability.  相似文献   

3.
老龄化个体出现的认知障碍在某种程度上是由于语言的认知老化所导致,因此,了解语言认知老化的具体表现、老化机制及其神经基础对于延缓语言认知老化、矫正老年痴呆有重要意义。首先基于理解和产生两个维度,分别从词汇、句子和文本三个层面分析了语言认知老化的表现,而后着重从工作记忆的角度分析了语言认知老化的认知机制,在此基础上,进一步从词汇加工、语义提取、句法分析三个方面分析了语言认知老化的神经基础,并指出半球不对称性减弱和脑区的弥散性激活是语言认知老化的主要神经表现。最后,围绕着语言认知老化的"发展进程、领域表现形式、干预矫正方法"三个必须解决的问题展开讨论,为该领域未来的发展做出理论上的铺垫。  相似文献   

4.
Amphibian vision is one of the most comprehensively studied of all vertebrate sensory systems. However, the processes of object recognition and memory in anuran amphibians have resisted satisfactory explanation. Our research shows that insight to the issue of visual discrimination and recognition in toads may be gained by investigation of the specialized and complementary functions carried out by the left and right brain hemispheres. We report that specialized processes associated with the left eye (right hemisphere) of the Bufo marinus toad carry out decisions to view and strike at complex prey stimuli recognized as 'novel.' This was demonstrated in the toads' preferences when provided a choice between identical novel insect models presented simultaneously into the left and right lateral, monocular visual fields. In a second experiment, videotaped trials of toad groups competing in an open field for live crickets were analysed for lateralized prey-catching behaviour. Concomitant with a preference for directing agonistic strikes at conspecifics within the left visual hemifield, toads were found to possess a significant preference for directing predatory responses at the familiar prey viewed in the right visual hemifield. The preference for directing prey-catching responses at freely moving crickets in the right visual hemifield supports the earlier findings drawn from automated and familiar model insect prey. We present a hypothesis explaining differences in hemispheric processing in toads responding to 'novel' and 'familiar' prey types, utilizing a range of long-term memories found to be lateralized in other vertebrates.  相似文献   

5.
People can discriminate cheaters from cooperators by their appearance. However, successful cheater detection can be thwarted by a posed smile, which cheaters display with greater emotional intensity than cooperators. The present study investigated the underlying neural and cognitive mechanisms of a posed smile, which cheaters use to conceal their anti-social attitude, in terms of hemifacial asymmetries of emotional expressions. Raters (50 women and 50 men) performed trustworthiness judgments on composite faces of cheaters and cooperators, operationally defined by the number of deceptions in an economic game. The left–left composites of cheaters were judged to be more trustworthy than the right–right composites when the models posed a happy expression. This left-hemiface advantage for the happy expression was not observed for cooperators. In addition, the left-hemiface advantage of cheaters disappeared for the angry expression. These results suggest that cheaters used the left hemiface, which is connected to the emotional side of the brain (i.e., the right hemisphere), more effectively than the right hemiface to conceal their anti-social attitude.  相似文献   

6.
The ability to process simultaneously presented auditory and visual information is a necessary component underlying many cognitive tasks. While this ability is often taken for granted, there is evidence that under many conditions auditory input attenuates processing of corresponding visual input. The current study investigated infants' processing of visual input under unimodal and cross-modal conditions. Results of the three reported experiments indicate that different auditory input had different effects on infants' processing of visual information. In particular, unfamiliar auditory input slowed down visual processing, whereas more familiar auditory input did not. These results elucidate mechanisms underlying auditory overshadowing in the course of cross-modal processing and have implications on a variety of cognitive tasks that depend on cross-modal processing.  相似文献   

7.
This article introduces a new technique designed to study the flow of information through processing stages in choice reaction time tasks. The technique was designed to determine whether response preparation can begin before stimulus identification is complete ("continuous" models), or if a stimulus must be fully identified prior to any response activation ("discrete" models). To control the information available at various times during stimulus identification, some relevant stimulus characteristics were made easy to discriminate and some were made hard to discriminate. The experimental strategy was to look for effects of partial output based on information conveyed by characteristics that were easy to discriminate. The technique capitalized on the fact, demonstrated in Experiment 1, that preparation of two response fingers on the same hand is more effective than preparation of two response fingers on different hands. The usefulness of partial output was varied by manipulating the assignments of stimuli to responses. For some mappings partial information could contribute to effective response preparation because the responses consistent with partial information were assigned to fingers on the same hand. For other mappings partial information could not contribute to effective response preparation because the responses consistent with partial information were assigned to fingers of different hands. Performance differences between these mappings were considered evidence that partial information about a stimulus was transmitted to response activation processes before the stimulus was uniquely identified, and thus were considered evidence against discrete transmission of information about the stimulus as a whole. A variety of stimulus sets were studied; the results suggest that information is transmitted discretely with respect to stimulus codes, although distinct codes activated by a single stimulus may be transmitted at different times.  相似文献   

8.
The present study investigated cerebral asymmetries in accessing multiple meanings of two types of homographs: homophonic homographs (e.g., bank) and heterophonic homographs (e.g., tear). Participants read homographs preceded by either a biasing or a non-biasing sentential context and performed a lexical decision on lateralized targets presented 150 ms after onset of the sentence-final ambiguous prime. Targets were either related to the dominant or the subordinate meaning of the preceding homograph or were unrelated to it. In the case of homophonic homographs – our results converge with previous findings: both activation and selection processes are faster in the LH than in the RH. Importantly, however, in the case of heterophonic homographs – opposite asymmetries were found. These results suggest that semantic asymmetries are modulated by phonology. They are discussed in the context of a model of functional architecture of reading in the two hemispheres in which orthography, phonology and semantics are fully interconnected in the LH, whereas in the RH, orthography and phonology are not directly connected, such that phonological processes are mediated by semantics.  相似文献   

9.
In a series of experiments, students were presented with selections of brief encyclopedia articles and biographical sketches, and asked to state which they preferred to read, and which they actually found to be most interesting after the reading. In all experiments, interest ratings were clearly influenced by amount of prior knowledge of the topic in question. There was in some cases a tendency to prefer less known to better known items, but more often familiar topics or persons were thought of as more interesting than unfamiliar ones. The results are compatible with the hypothesis that the inherent interestingness of a communication is directly related to its degree of perceived informativeness, and that both are dependent upon the possibility of getting to know something new about something already sufficiently well known. This study was written while the author was on sabbatical leave at the Aesthetics Research Group, University of Leicester, and was supported by a grant from the Norwegian Research Council for Science and the Humanities.  相似文献   

10.
In honeybees, Apis mellifera L., the proboscis extension reflex (PER) can be conditioned by associating an odor stimulus (CS) with a sucrose reward (US). As the neural structures involved in the detection and integration of CS and US are bilaterally symmetrical in the bee brain, we ask what respective role each brain side plays in the conditioning process. More specifically, the US normally used in conditioning experiments is the compound stimulation of the antennae (which triggers the PER) and of the proboscis (where bees lick the sucrose solution). Anatomically, the brain receives unilateral US input through each antenna, but bilateral input from the proboscis. By controlling each US component, we show that an antenna–US produces unilateral sensitization, whereas a proboscis–US or a compound–US induces bilateral sensitization. Bees can learn a unilateral odor CS with all three USs, but when a proboscis–US is used, new learning is inhibited on the contralateral side, owing to a possible US-preexposure effect. Furthermore, we show that the antenna–US induces both unilateral and bilateral reinforcement processes, whereas the proboscis–US produces only bilateral effects. Based on these data, we propose a functional model of the role of each brain side in processing lateralized CSs and USs in olfactory learning in honeybees.  相似文献   

11.
Previous literature has argued that proficient bilingual speakers often demonstrate monolingual-equivalent structural processing of language (e.g., the processing of structural ambiguities; Frenck-Mestre, 2002). In this paper, we explore this thesis further via on-line examination of the processing of syntactically complex structures with three populations: those who classify as monolingual native English speaker (MNES), those who classify as non-native English speakers (NNES), and those who calssify as bilingual native English speakers (BNES). On-line measures of processing of object-relative constructions demonstrated that both NNES and BNES have different patterns of performance as compared to MNES. Further, NNES and BNES speakers perform differently from one another in such processing. The study also examines the activation of lexical information in biasing contexts, and suggests that different processes are at work in the different type of bilinguals examined here. The nature of these differences and the implications for developing sensitive models of on-line language comprehension are developed and discussed.  相似文献   

12.
13.
14.
For more than a century, psychologists have been intrigued by the idea that mental representations of perceived human actions are closely connected with mental representations of performing those same actions. In this article, connections between input and output representations are considered in terms of the potential for imitation. A broad range of evidence suggests that, for imitatible stimuli, input and output representations are isomorphic to one another, allowing mutual influence between perception and motoric planning that is rapid, effortless, and possibly obligatory. Thus, the cognitive consequences of imitatibility may underlie such diverse phenomena as phoneme perception; imitation in neonates; echoic memory; stimulus-response compatibility; conduction aphasia; maintenance rehearsal; and a variety of developmental and social activities such as language acquisition, social learning, empathy, and monitoring one's own behavior.  相似文献   

15.
This study explores oscillatory brain activity by means of event-related synchronization and desynchronization (%ERS/ERD) of EEG activity during the use of phonological and orthographic-morphological spelling strategies in L2 (English) and L1 (German) in native German speaking children. EEG was recorded while 33 children worked on a task requiring either phonological or orthographic-morphological spelling strategies. L2 processing elicited more theta %ERS than L1 processing (particularly at bilateral frontal and right posterior parietal sites) which might suggest a stronger involvement of semantic encoding and retrieval of the less familiar L2. The highest level of theta %ERS was revealed for the orthographic-morphological strategy in L2 which might indicate a more intense way of lexical retrieval compared to the phonological strategy in L2 and the orthographic-morphological strategy in L1. Analyses moreover revealed that phonological processing (both in L1 and L2) was associated with comparatively strong left-hemispheric %ERD in the upper alpha frequency band.  相似文献   

16.
The use of multiple familiar views of objects to facilitate recognition of novel views has been addressed in a number of behavioral studies, but the results have not been conclusive. The present study was a comprehensive examination of view combination for different types of novel views (internal or external to the studied views) and different objects (amoeboid objects and objects composed of geons; objects with and without self-occlusion across rotation). The authors found that the advantage gained from the study of 2 views was more than the generalization from each of the studied views presented alone. This facilitation occurred only for internal views but not external views. In addition, the benefits from the study of 2 views diminished when (a) the studied views did not share the same visible features and when (b) the studied views were separated by a small angular difference.  相似文献   

17.
In three experiments, native Chinese speakers were asked to use their native and non-native languages to read and translate Chinese words and to name pictures. In Experiment 1, four groups of subjects with various degrees of proficiency in their second language, English, participated. In Experiments 2 and 3, subjects were first asked to learn a list of words in a new language, French, using either Chinese words or pictures as media; then they performed the reading, naming, and translation tasks. All subjects performed better in reading words than in naming pictures, when responding in Chinese. When the response was in the non-native language (English or French), high-learning subjects were equally efficient in translation and picture-naming tasks. Low-learning subjects, however, performed better in either the translation or the picture-naming task, depending on their learning strategies. These results are consistent with the idea that both proficiency in a non-native language and the strategy for acquiring the language are main determinants for the pattern of lexical processing in that language.  相似文献   

18.
This paper evaluates whether or not simplicity or minimalistic heuristics, which are posited to account for local ambiguity resolution at the level of structural processing and for the lack of inferential elaboration during discourse processing, represent the most accurate account of language processing. Evidence from on-line studies is presented which suggests that alternative, more knowledge-based mechanisms for handling processing are brought to bear in these situations.  相似文献   

19.
The modality effect in immediate recall refers to superior recall of the last few items within lists presented in spoken as opposed to printed form. The locus of this well-known effect has been unclear. N. Cowan, J. S. Saults, E. M. Elliott, and M. Moreno (2002) introduced a new method to distinguish between the effects of input serial position, output serial position, and the number of items yet to be recalled and found that large modality effects occurred only in conditions in which delay and interference at output (from items already recalled) was high. The authors replicated that finding, even when the response period included output interference acoustically similar to the spoken stimuli to be recalled. However, the authors found that output delay and interference act only by lowering the level of performance to a more sensitive range. The modality effect thus originates during encoding of the list to be recalled, not during output.  相似文献   

20.
A digital pursuit rotor task was used to measure dual task costs of language production by young and older adults. After training on the pursuit rotor, participants were asked to track the moving target while providing a language sample. When simultaneously engaged, young adults experienced greater dual task costs to tracking, fluency, and grammatical complexity than older adults. Older adults were able to preserve their tracking performance by speaking more slowly. Individual differences in working memory, processing speed, and Stroop interference affected vulnerability to dual task costs. These results demonstrate the utility of using a digital pursuit rotor to study the effects of aging and dual task demands on language production and confirm prior findings that young and older adults use different strategies to accommodate to dual task demands.  相似文献   

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