文本阅读中预期推理激活与编码的语境条件研究

本研究通过三个实验考察了语义联系和因果制约对文本阅读中预期推理激活和编码的贡献。结果表明,预期语境与预期事件间的语义联系不能使预期推理在文本阅读过程中得到激活和编码,语境与预期事件间的强因果关系是文本阅读过程中预期推理激活与编码的必要条件;提示阅读过程中的预期是因果预期而非联想预期。结果为建构主义推理观提供了实验依据。     

Unit price and choice in a token-reinforcement context

Pigeons were exposed to multiple and concurrent second-order schedules of token reinforcement, with stimulus lights serving as token reinforcers. Tokens were produced and exchanged for food according to various fixed-ratio schedules, yielding equal and unequal unit prices (responses per unit food delivery). On one schedule (termed the standard schedule), the unit price was held constant across conditions. On a second schedule (the alternative schedule), the unit price was either the same or different from the standard. Under conditions with unequal unit prices, near-exclusive preference for the lower unit price was obtained. Under conditions with equal unit prices, the direction and degree of preference depended on ratio size (number of responses per exchange period). When this ratio differed, strong preferences for the smaller ratio were observed. When this ratio was equal, preferences were nearer indifference. Response rates on the multiple schedule were generally consistent with the preference data in showing sensitivity to ratio size. Results are discussed in terms of a unit-price model that includes handling and reinforcer immediacy as additional costs. On the whole, results show that preferences were determined primarily by delay to the exchange period.     

The effects of meaningful irrelevant speech and road traffic noise on teachers' attention, episodic and semantic memory

The aim of the present experiment was to examine the effects of meaningful irrelevant speech and road traffic noise on attention, episodic and semantic memory, and also to examine whether the noise effects were age-dependent. A total of 96 male and female teachers in the age range of 35-45 and 55-65 years were randomly assigned to a silent or the two noise conditions. Noise effects found in episodic memory were limited to a meaningful text, where cued recall contrary to expectations was equally impaired by the two types of noise. However, meaningful irrelevant speech also deteriorated recognition of the text, whereas road traffic noise caused no decrement. Retrieval from two word fluency tests in semantic memory showed strong effects of noise exposure, one affected by meaningful irrelevant speech and the other by road traffic noise. The results implied that both acoustic variation and the semantic interference could be of importance for noise impairments. The expected age-dependent noise effects did not show up.     

Parallel processing across neural systems: implications for a multiple memory system hypothesis

A common conceptualization of the organization of memory systems in brain is that different types of memory are mediated by distinct neural systems. Strong support for this view comes from studies that show double (or triple) dissociations between spatial, response, and emotional memories following selective lesions of hippocampus, striatum, and the amygdala. Here, we examine the extent to which hippocampal and striatal neural activity patterns support the multiple memory systems view. A comparison is made between hippocampal and striatal neural correlates with behavior during asymptotic performance of spatial and response maze tasks. Location- (or place), movement, and reward-specific firing patterns were found in both structures regardless of the task demands. Many, but not all, place fields of hippocampal and striatal neurons were similarly affected by changes in the visual and reward context regardless of the cognitive demands. Also, many, but not all, hippocampal and striatal movement-sensitive neurons showed significant changes in their behavioral correlates after a change in visual context, irrespective of cognitive strategy. Similar partial reorganization was observed following manipulations of the reward condition for cells recorded from both structures, again regardless of task. Assuming that representations that persist across context changes reflect learned information, we make the following conclusions. First, the consistent pattern of partial reorganization supports a view that the analysis of spatial, response, and reinforcement information is accomplished via an error-driven, or match-mismatch, algorithm across neural systems. Second, task-relevant processing occurs continuously within hippocampus and striatum regardless of the cognitive demands of the task. Third, given the high degree of parallel processing across allegedly different memory systems, we propose that different neural systems may effectively compete for control of a behavioral expression system. The strength of the influence of any one neural system on behavioral output is likely modulated by factors such as motivation, experience, or hormone status.     

On the Representation of Inflections and Derivations: Data from Spanish

The four experiments reported in this paper were designed to determine to what extent words are lexically represented in terms of their morphological structure. The experiments are carried out in Spanish, a language with rich morphological resources, using a priming paradigm and a lexical decision task. In particular, they examined the pattern of priming effects in regular inflected words with gender and in derived words, in comparison to those produced by orthographically and semantically related words, by manipulating form similarity and semantic transparency. The results showed, on the one hand, that regular inflected words produced reliable facilitatory effects which are not driven just by form relatedness (Experiments 1 and 2). On the other hand, they showed that both transparent and nontransparent derived forms produced facilitatory effects distinct from purely orthographic and semantic effects (Experiments 3 and 4.). In general, these findings suggest that morphological information is represented in the mental lexicon and may play a central role in the individuation and retrieval of lexical entries.     

视觉工作记忆中的子系统

由于在预实验中发现记忆复合物体(multi—feature objects)时存在子系统优势,在本实验中,研究了记忆单特征物体(single—feature objects)时,是否存在子系统优势。被试为中国科学技术大学学生17人。要求被试记忆同样数目的单特征物体,条件1下物体属性相同,条件2下物体分属两种属性。通过正确率分析,条件2的成绩好于条件1。这个结果表明：单特征物体记忆时存在子系统优势。     

Neuronal substrates of relapse to cocaine-seeking behavior: role of prefrontal cortex

The return to drug seeking, even after prolonged periods of abstinence, is a defining feature of cocaine addiction. The neural circuitry underlying relapse has been identified in neuropharmacological studies of experimental animals, typically rats, and supported in brain imaging studies of human addicts. Although the nucleus accumbens (NAcc), which has long been implicated in goal-directed behavior, plays a critical role in this circuit, the prefrontal cortex (PFC) appears to process the events that directly trigger relapse: exposure to acute stress, cues previously associated with the drug, and the drug itself. In this paper, we review animal models of relapse and what they have revealed about the mechanisms underlying the involvement of the NAcc and PFC in cocaine-seeking behavior. We also present electrophysiological data from PFC illustrating how the hedonic, motor, motivational, and reinforcing effects of cocaine can be analyzed at the neuronal level. Our preliminary findings suggest a role for PFC in processing information related to cocaine seeking but not the hedonic effects of the drug. Further use of this recording technology can help dissect the functions of PFC and other components of the neural circuitry underlying relapse.     

Language effects in magnitude comparison: small, but not irrelevant

It is assumed that number magnitude comparison is performed by assessing magnitude representation on a single analog mental number line. However, we have observed a unit-decade-compatibility effect in German which is inconsistent with this assumption (Nuerk, Weger, & Willmes, 2001). Incompatible magnitude comparisons in which decade and unit comparisons lead to different responses (e.g., 37_52 for which 3<5, but 7>2) are slower and less accurately responded to than compatible trials in which decade and unit comparisons lead to the same response (e.g., 42_57, for which 4<5 and 2<7). As overall distance was held constant, a single holistic magnitude representation could not account for this compatibility effect. However, because of the inversion property of the corresponding German two-digit number words ("einundzwanzig" ), the language-generality of the effect is questionable. We have therefore examined the compatibility effect with native English speakers. We were able to replicate the compatibility effect using Arabic notation. Thus, the compatibility effect is not language-specific. However, in cross-linguistic analyses language-specific modulations were observed not only for number words but also for Arabic numbers. The constraints imposed on current models by the verbal mediation of Arabic number comparison are discussed.     

Processing "d-linked" phrases

Linguists draw a distinction between two types of interrogatives: discourse linked (d-linked) phrases such as which man, which implies the existence of a set of contextually determined entities (men) from which the speaker is asking for a choice, and non–d-linked interrogatives such as who, which carry no such implication. Two questionnaires and an on-line reading study showed that readers prefer a d-linked phrase more than a non–d-linked phrase as the antecedent for a pronoun, suggesting that d-linked phrases are immediately instantiated in a discourse representation that is checked during the process of pronoun interpretation. Comparable difficulty is not observed for non–d-linked interrogatives. A questionnaire and an on-line listening study also showed that readers and listeners were more willing to accept a grammatical island violation containing a pronoun when the pronoun's antecendent was a d-linked interrogative than when the antecedent was non–d-linked, suggesting that they check a discourse representation for the pronoun antecedent. All results suggest that d-linked phrases are immediately interpreted in a discourse representation, not just in a syntactic representation.     

Semantic representations of word meanings by the cerebral hemispheres

Two priming experiments investigated kind and strength of semantic knowledge underlying known, frontier, and unknown low frequency words. Results from Experiment 1 suggest that known words reflect categorical knowledge, but frontier and unknown words reflect thematic knowledge. Thematic knowledge for frontier words appears to be stronger than that for unknown words. Experiment 2 entailed visual half-field presentation of targets. All facilitory effects were restricted to the lvf/RH, and inhibitory effects to the rvf/LH. Experiment 1 findings were mirrored by the RH. Thematic knowledge appears to precede categorical knowledge for the RH, but the opposite may be true of the LH. Results are also discussed in terms of the RH role in meaning acquisition and metacontrol.