首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
In a temporal double bisection task, animals learn two discriminations. In the presence of Red and Green keys, responses to Red are reinforced after 1-s samples and responses to Green are reinforced after 4-s samples; in the presence of Blue and Yellow keys, responses to Blue are reinforced after 4-s samples and responses to Yellow are reinforced after 16-s samples. Subsequently, given a choice between Green and Blue, the probability of choosing Green increases with the sample duration-the context effect. In the present study we asked whether this effect could be predicted from the stimulus generalization gradients induced by the two basic discriminations. Six pigeons learned to peck Green following 4-s samples (S(+)) but not following 1-s samples (S(-)) and to peck Red following 4-s samples (S(+)) but not following 16-s samples (S(-)). Temporal generalization gradients for Green and Red were then obtained. Finally, the pigeons were given a choice between Green and Red following sample durations ranging from 1 to 16 s. Results showed that a) the two generalization gradients had the minimum at the S(-) duration, an intermediate value between the S(-) and the S(+) durations, and the maximum at the S(+) as well as more extreme durations; b) on choice trials, preference for Green over Red increased with sample duration, the context effect; and c) the two generalization gradients predicted the average context effect well. The Learning-to-Time model accounts for the major trends in the data.  相似文献   

2.
功能磁共振技术在表象研究中得到广泛应用是表象研究追求客观化精确性的必然趋势。本文介绍了功能磁共振多变量模式分析方法及其演变历程,探讨了借助该方法实现“视觉表象可视化”的理论依据与亟待解决的关键问题。分析指出“视觉表象可视化”将为表象研究提供全新的研究视角与方法途径。  相似文献   

3.
Auditory orienting and discrimination were studied with combined multi-channel EEG and MEG recordings in a patient with unilateral amygdala-hippocampus-partial temporal lobe resection of the right hemisphere. The results revealed abnormalities of habituation in alerting- and orienting-related responses, and discrimination-related responses, elicited by auditory stimulation contralateral to the resected cerebral hemisphere. These results give support to the notions about the role of the amygdala and hippocampus in alerting and orienting, respectively, and of the temporal cortex in auditory discrimination.  相似文献   

4.
Understanding of sensory and cognitive brain processes requires information about activation timing within and between different brain sites. Such data can be obtained by magnetoencephalography (MEG) that tracks cortical activation sequences with a millisecond temporal accuracy. MEG is gaining a well-established role in human neuroscience, complementing with its excellent temporal resolution the spatially more focused brain imaging methods. As examples of MEG's role in cognitive neuroscience, we discuss time windows related to cortical processing of sensory and multisensory stimuli, effects of the subject's own voice on the activity of their auditory cortex, timing of brain activation in reading, and cortical dynamics of the human mirror-neuron system activated when the subject views another person's movements.  相似文献   

5.
王润洲  毕鸿燕 《心理科学进展》2022,30(12):2764-2776
发展性阅读障碍的本质一直是研究者争论的焦点。大量研究发现,阅读障碍者具有视听时间整合缺陷。然而,这些研究仅考察了阅读障碍者视听时间整合加工的整体表现,也就是平均水平的表现,却对整合加工的变化过程缺乏探讨。视听时间再校准反映了视听时间整合的动态加工过程,对内部时间表征与感觉输入之间差异的再校准困难则会导致多感觉整合受损,而阅读障碍者的再校准相关能力存在缺陷。因此,视听时间再校准能力受损可能是发展性阅读障碍视听时间整合缺陷的根本原因。未来的研究需要进一步考察发展性阅读障碍者视听时间再校准能力的具体表现,以及这些表现背后的认知神经机制。  相似文献   

6.
Two experiments studied the emergence of bindings between stimulus features (object files) and between stimulus and response features (event files) over time. Choice responses (R2) were signalled by the shape of a stimulus (S2) that followed another stimulus (S1) of the same or different shape, location, and colour. S1 did not require a response (Experiment 1) or trigger a precued simple response (R1) that was or was not repeated by R2 (Experiment 2). Results demonstrate that the mere cooccurrence of stimulus features, and of stimuli and responses, is sufficient to bind their codes. Bindings emerge quickly and remain intact for at least four seconds. Which features are considered depends on their task‐relevance; hence, integration reflects the current attentional set. There was no consistent trend toward higher order interactions as a function of time or of the amount of attention devoted to S1, suggesting that features are not integrated into a single, global superstructure, but enter independent local bindings presumably subserving different functions.  相似文献   

7.
8.
研究探讨中文阅读中的副中央凹-中央凹效应。副中央凹-中央凹效应是指副中央凹处词的特性对中央凹处词汇加工的影响。实验以27名大学生为被试,采用句子阅读材料,考察词n的语义透明度特性对词n-1(高频、低频)加工的影响。结果表明,词n的语义透明度的高低对词n-1(高频、低频)的加工没有影响,没有出现副中央凹-中央凹效应。实验结果支持E-Z读者模型的假设。  相似文献   

9.
Lucchiari, C. & Pravettoni, G. (2010). Feedback related brain activity in a gambling task: A temporal analysis of EEG correlates. Scandinavian Journal of Psychology 51, 449–454. The pattern of neural correlates of feedback processing has been the subject of a number of studies, using both neuroimaging and electrophysiological recordings. A complex functional network was found to be activated after a choice in order to process a feedback and sustain an adaptive behavior. However, many aspects of this network are still unclear and further research is needed to better understand this process. We conducted an EEG study using a simple gambling task. Twenty three subjects participated to the study. We analyzed both EEG power spectrum and ERP components evoked by presentation of a feedback signal (money gain or loss) during a simple gambling task. Our data confirmed that a negative ERP component is present about 270 ms after feedback, particularly relevant following a choice with negative outcome. Furthermore, the theta and delta oscillatory activity seem to be correlated to a dynamic decision‐making process within specific cortical networks. In particular, theta activity showed a valence dependent development between 150 and 350 ms post‐feedback onset. Differently from previous studies (Cohen, Elger & Ranganath, 2007; Marco‐Pallares, Cucurell, Cunillera et al., 2008), we did not find any valence effect in beta range. However, our data are consistent with Christie and Tata (2009) , probably due to the nature of the gambling task used in both studies. In conclusion, our data, in line with some prior findings showed that the feedback related response is correlated to a complex pattern of cortical activation probably mediated by theta and delta activity.  相似文献   

10.
A practical intervention program, targeting the safety belt use of pizza deliverers at two stores, increased significantly the use of both safety belts (143% above baseline) and turn signals (25% above baseline). Control subjects (i.e., pizza deliverers at a third no-intervention store and patrons driving to the pizza stores) showed no changes in belt or turn signal use over the course of 7-month study. The intervention program was staggered across two pizza stores and consisted of a group meeting wherein employees discussed the value of safety belts, received feedback regarding their low safety belt use, offered suggestions for increasing their belt use, and made a personal commitment to buckle up by signing buckle-up promise cards. Subsequently, employee-designed buckle-up reminder signs were placed in the pizza stores. By linking license plate numbers to individual driving records, we examined certain aspects of driving history as moderators of pre- and postintervention belt use. Although baseline belt use was significantly lower for drivers with one or more driving demerits or accidents in the previous 5 years, after the intervention these risk groups increased their belt use significantly and at the same rate as drivers with no demerits or accidents. Whereas baseline belt use was similar for younger (under 25) and older (25 or older) drivers, younger drivers were markedly more influenced by the intervention than were older drivers. Individual variation in belt use during baseline, intervention, and follow-up phases indicated that some drivers require more effective and costly intervention programs to motivate their safe driving practices.  相似文献   

11.
It is well established that the temporal proximity of two events is a fundamental cue to causality. Recent research with adults has shown that this relation is bidirectional: events that are believed to be causally related are perceived as occurring closer together in time—the so‐called temporal binding effect. Here, we examined the developmental origins of temporal binding. Participants predicted when an event that was either caused by a button press, or preceded by a non‐causal signal, would occur. We demonstrate for the first time that children as young as 4 years are susceptible to temporal binding. Binding occurred both when the button press was executed via intentional action, and when a machine caused it. These results suggest binding is a fundamental, early developing property of perception and grounded in causal knowledge. A video abstract of this article can be viewed at https://www.youtube.com/watch?v=EQC_MqjxZQQ  相似文献   

12.
The ability of the perturbation model (Jones & Wearden, 2003) to account for reference memory function in a visual temporal generalization task and auditory and visual reproduction tasks was examined. In all tasks the number of presentations of the standard was manipulated (1, 3, or 5), and its effect on performance was compared. In visual temporal generalization the number of presentations of the standard did not affect the number of times the standard was correctly identified, nor did it affect the overall temporal generalization gradient. In auditory reproduction there was no effect of the number of times the standard was presented on mean reproductions. In visual reproduction mean reproductions were shorter when the standard was only presented once; however, this effect was reduced when a visual cue was provided before the first presentation of the standard. Whilst the results of all experiments are best accounted for by the perturbation model there appears to be some attentional benefit to multiple presentations of the standard in visual reproduction.  相似文献   

13.
In Experiment 1, 6 college students were given generalization tests using 25 line lengths as samples with a long line, a short line, and a “neither” option as comparisons. The neither option was to be used if a sample did not go with the other comparisons. Then, four-member equivalence classes were formed. Class 1 included three nonsense words and the short line. Class 2 included three other nonsense words and the long line. After repeating the generalization test for line length, additional tests were conducted using members of the equivalence classes (i.e., nonsense words and lines) as comparisons and intermediate-length lines as samples. All Class 2 comparisons were selected in the presence of the test lines that also evoked the selection of the long line in the generalization test that had been given before equivalence class formation. Class 1 yielded complementary findings. Thus, the preclass primary generalization gradient predicted which test lines acted as members of each equivalence class. Regardless of using comparisons that were nonsense words or lines, the post-class-formation gradients overlapped, showing the substitutability of class members. Experiment 2 assessed the discriminability of the intermediate-length test lines from the Class 1 (shortest) and Class 2 (longest) lines. The test lines that functioned as members of an equivalence class were discriminable from the line that was a member of the same class by training. Thus, these test lines also acted as members of a dimensionally defined class of “long” or “short” lines. Extension of an equivalence class, then, involved its merger with a dimensionally defined class, which converted a close-ended class to an open-ended class. These data suggest a means of predicting class membership in naturally occurring categories.  相似文献   

14.
Recent studies have revealed that the temporal lobe, a cortical region thought to be in charge of episodic and semantic memory, is involved in creative insight. This work examines the contributions of discrete temporal regions to insight. Activity in the medial temporal regions is indicative of novelty recognition and detection, which is necessary for the formation of novel associations and the “Aha!” experience. The fusiform gyrus mainly affects the formation of gestalt-like representation and perspective taking. The anterior and posterior middle temporal gyri (MTG) are individually associated with extensive semantic processing and inhibiting salient or routine word associations, which are necessary to form non-salient, novel and remote associations. The anterior and posterior superior temporal gyri (STG) are individually responsible for integrating/binding and accessing various types of available conceptual representations. Based on the current knowledge, an integrated model of the temporal lobe's role in insight and some future directions are proposed.  相似文献   

15.
Compatibility effects (CEs) arise when multiple stimuli fall within the visual field, providing an indication of stimulus processing. Previous research demonstrated that exogenous factors (e.g., luminance) influence the magnitude of CEs and their time course. The current research investigated the influence of endogenous factors. We used a flanker paradigm with a variable temporal delay (SOA) between a flanker and a subsequent central stimulus appearing. To manipulate endogenous factors, we required responses to the flanker on either half or all of the trials. The results indicate that increasing the task relevance of the flanker strengthened the initial positive CE (measured at short SOAs), consistent with past findings related to exogenous factors. However, at longer SOAs, the CE did not reverse into a negative CE, which stands against findings related to exogenous factors. These results indicate that CEs are subject to endogenous modulation, but the temporal dynamics do not mimic exogenous modulation.  相似文献   

16.
Processing speed is a component of general intelligence and an indicator of learning potential. There is a need for robust measures of mental speed based on contemporary theoretical developments. The current study addressed this need by proposing a mental speed test for children aged 60 to 96 months (5 to 8 years) and examining its psychometric properties. The test included indicators of perceptual speed, memory speed, reasoning speed, and fluency-flexibility speed presented through nonverbal items administered individually using touchscreen tablets. After establishing gender non-bias and concurrent validity with a contemporary intelligence test (i.e., ASIS, r = .59) with 107 children, the next administration included 373 children. Exploratory factor analysis (EFA) with subtest scores revealed a single-factor structure accounting for 45% of the total variance. Additional data from 212 children were used to assess structural validity and gender bias, which showed acceptable goodness of fit, providing evidence of the validity and reliability of the new measure for further use.  相似文献   

17.
In listening to speech, people have been shown to apply several types of adjustment to their phonemic categories that take into account variations in the prevailing linguistic environment. These adjustments include selective adaptation, lexically driven recalibration, and audiovisually determined recalibration. Prior studies have used dual task procedures to test whether these adjustments are automatic or if they require attention, and all of these tests have supported automaticity. The current study instead uses a method of targeted distraction to demonstrate that lexical recalibration does in fact require attention. Building on this finding, the targeted distraction method is used to measure the period of time during which the lexical percept remains malleable. The results support a processing window of approximately one second, consistent with the results of a small number of prior studies that bear on this question. The results also demonstrate that recalibration is closely linked to the completion of lexical access.  相似文献   

18.
Numerous studies have indicated that, consistent with current “cognitive” accounts of information processing, human Pavlovian autonomic discrimination acquisition cannot occur without awareness of the CS-US relationship. However, extinction studies have suggested that awareness is not necessary, findings that, in information-processing terms, have been explained by assuming that the processing by the extinction stage is parallel (automatic) rather than serial (controlled). This explanation was tested in an 80-subject study. The first, acquisition phase was a standard semantic differential conditioning arrangement with a 96-db white noise as US, and a “long” CS-US interval of 8 s, with ten trials each of CS+ (paired with US) and CS− (unpaired) trials. In extinction (USs omitted), in order to obtain non-autonomic indices of processing and thereby test the information-processing account of “unaware” autonomic conditioning during extinction, a dichotic listening task was implemented, with the CSs presented in the unattended channel (ear), while the subject had to perform a semantic differential reaction task in an attended-to channel (other ear). In early extinction, the electrodermal response occurring at an interval of 9–15 s after CS onset (i.e., following placement of the US during acquisition) and the finger-pulse-volume response occurring at an interval of 4–11 s after CS onset both showed reliable conditioning, but reaction-time and subjective-report data for the recognized critical words indicated serial rather than parallel processing of the CSs during extinction.  相似文献   

19.
Previous meta-analyses have estimated that the intention–behaviour association in physical activity (PA) is large in magnitude. However, these prior meta-analyses have also revealed a large degree of heterogeneity, suggesting the presence of moderating variables. This study examines the impact of one such moderator, testing the hypothesis that the magnitude of the association between intention and behaviour decreases as the temporal separation between the two increases. A systematic literature search was used to identify published and unpublished studies that met the inclusion criteria. A random-effects meta-regression was conducted to test the study hypothesis. A total of 78 journal articles and 11 unpublished dissertations were identified, yielding 109 effect sizes. The mean number of weeks between the measurement of intention and behaviour was 5.4 (SD = 6.6, range = .43, 26). The average correlation between intention and behaviour was r = 0.51. In line with theoretical predictions, temporal separation was a significant moderator of the intention–behaviour correlation (B = ?.014, p < .001) and explained 24% of the between-study variance. This result remained unchanged when entered simultaneously with several control variables. The results of this analysis have important implications both for researchers and for intervention designers aiming to increase rates of PA.  相似文献   

20.
Although the N400 ERP component has been extensively studied in younger adults, the underlying mechanisms are still unclear. In older adults, N400 ERP studies have shown less efficient use of context compared to younger adults. Here, we asked whether the mechanisms underlying the N400 effect are the same in terms of predictiveness and congruency in younger and older adults. We used a simple picture-word matching task in which we crossed predictiveness and congruency. Our results indicate a three-way interaction between predictiveness, congruency, and age, in that, younger adults showed an N400 effect only in strongly constrained conditions; whereas, older adults showed an effect in both strongly- and weakly constrained conditions. This interaction was not modulated by language experience or cognitive decline. Our results support either two separate mechanisms (lexical access and integration) that run in parallel and are modulated by age or a common prediction error mechanism that changes with age.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号