《Brain and cognition》2014

Human memory is an enigmatic component of cognition which many researchers have attempted to comprehend. Accumulating studies on functional connectivity see brain as a complex dynamic unit with positively and negatively correlated networks in perfect coherence during a task. We aimed to examine coherence of network connectivity during visual memory encoding and retrieval in the context of education. School Educated (SE) and College Educated (CE) healthy volunteers (n = 60) were recruited and assessed for visual encoding and retrieval. Functional connectivity using seed to voxel based connectivity analysis of the posterior cingulate cortex (PCC) was evaluated. We noticed that there were reciprocal dynamic changes in both dorsolateral prefrontal cortex (DLPFC) region and PCC regions during working memory encoding and retrieval. In agreement with the previous studies, there were more positively correlated regions during retrieval compared to encoding. The default mode network (DMN) networks showed greater negative correlations during more attentive task of visual encoding. In tune with the recent studies on cognitive reserve we also found that number of years of education was a significant factor influencing working memory connectivity. SE had higher positive correlation to DLPFC region and lower negative correlation to DMN in comparison with CE during encoding and retrieval.  相似文献   

    

《Brain and cognition》2014

Behavioral studies suggested heightened impact of emotionally laden perceptual input in schizophrenia spectrum disorders, in particular in patients with prominent positive symptoms. De-coupling of prefrontal and posterior cortices during stimulus processing, which is related to loosening of control of the prefrontal cortex over incoming affectively laden information, may underlie this abnormality. Pre-selected groups of individuals with low versus high positive schizotypy (lower and upper quartile of a large screening sample) were tested. During exposure to auditory displays of strong emotions (anger, sadness, cheerfulness), individuals with elevated levels of positive schizotypal symptoms showed lesser prefrontal–posterior coupling (EEG coherence) than their symptom-free counterparts (right hemisphere). This applied to negative emotions in particular and was most pronounced during confrontation with anger. The findings indicate a link between positive symptoms and a heightened impact particularly of threatening emotionally laden stimuli which might lead to exacerbation of positive symptoms and inappropriate behavior in interpersonal situations.  相似文献   

    

Hendrik Hüttermann  Sabine Boerner 《European Journal of Work and Organizational Psychology》2013,22(6):833-854

Empirical research on the effects of functional diversity on team innovation has yielded largely inconsistent results, showing positive, negative, as well as nonsignificant effects. For capitalizing on the positive potential inherent in functionally diverse teams, opening the black box between cross-functionality and team innovation by analysing mediating and moderating processes thus seems to be highly relevant. In this article, task and relationship conflicts are introduced as mediators of functional diversity and team innovation. Within this framework, transformational leadership is discussed as a moderator. It will become apparent that the role of transformational leadership in fostering the innovativeness of cross-functional teams is rather ambiguous. The discussed mediators and the moderator transformational leadership are integrated into a comprehensive framework and propositions for future research are derived.  相似文献   

    

Fields L  Arntzen E  Nartey RK  Eilifsen C 《Journal of the experimental analysis of behavior》2012,97(2):163-181

Thirty college students attempted to form three 3-node 5-member equivalence classes under the simultaneous protocol. After concurrent training of AB, BC, CD, and DE relations, all probes used to assess the emergence of symmetrical, transitive, and equivalence relations were presented for two test blocks. When the A-E stimuli were all abstract shapes, none of 10 participants formed classes. When the A, B, D, and E stimuli were abstract shapes and the C stimuli were meaningful pictures, 8 of 10 participants formed classes. This high yield may reflect the expansion of existing classes that consist of the associates of the meaningful stimuli, rather than the formation of the ABCDE classes, per se. When the A-E stimuli were abstract shapes and the C stimuli became S(D)s prior to class formation, 5 out of 10 participants formed classes. Thus, the discriminative functions served by the meaningful stimuli can account for some of the enhancement of class formation produced by the inclusion of a meaningful stimulus as a class member. A sorting task, which provided a secondary measure of class formation, indicated the formation of all three classes when the emergent relations probes indicated the same outcome. In contrast, the sorting test indicated \"partial\" class formation when the emergent relations test indicated no class formation. Finally, the effects of nodal distance on the relatedness of stimuli in the equivalence classes were not influenced by the functions served by the C stimuli in the equivalence classes.  相似文献   

    

Nicole C. Groskreutz  Allen Karsina  Caio F. Miguel  Mark P. Groskreutz 《Journal of applied behavior analysis》2010,43(1):131-136

Six participants with autism learned conditional relations between complex auditory‐visual sample stimuli (dictated words and pictures) and simple visual comparisons (printed words) using matching‐to‐sample training procedures. Pre‐ and posttests examined potential stimulus control by each element of the complex sample when presented individually and emergence of additional conditional relations and oral labeling. Tests revealed class‐consistent performance for all participants following training.  相似文献   

    

Guinther PM  Dougher MJ 《Journal of the experimental analysis of behavior》2010,93(3):329-347

Contemporary behavior analytic research is making headway in characterizing memory phenomena that typically have been characterized by cognitive models, and the current study extends this development by producing \"false memories\" in the form of functional equivalence responding. A match-to-sample training procedure was administered in order to encourage participants to treat groups of unrelated English words as being interchangeable. Following training, participants were presented with a list of words from within one of the groups for a free recall test and a recognition test. Results showed that participants were more likely to falsely recall and recognize words that had been assigned to the same group as the list words during prior training, relative to words not assigned to the same group and relative to words that co-occurred with list words. These results indicate that semantic relatedness can be experimentally manipulated in order to produce specific false memories.  相似文献   

    

Lovett S  Rehfeldt RA  Garcia Y  Dunning J 《Journal of applied behavior analysis》2011,44(4):819-833

This study compared the effects of a computer-based stimulus equivalence protocol to a traditional lecture format in teaching single-subject experimental design concepts to undergraduate students. Participants were assigned to either an equivalence or a lecture group, and performance on a paper-and-pencil test that targeted relations among the names of experimental designs, design definitions, design graphs, and clinical vignettes was compared. Generalization of responding to novel graphs and novel clinical vignettes, as well as the emergence of a topography-based tact response after selection-based training, were evaluated for the equivalence group. Performance on the paper-and-pencil test following teaching was comparable for participants in the equivalence and lecture groups. All participants in the equivalence group showed generalization to novel graphs, and 6 participants showed generalization to novel clinical vignettes. Three of the 4 participants demonstrated the emergence of a topography-based tact response following training on the stimulus equivalence protocol.  相似文献   

    

Fienup DM  Critchfield TS 《Journal of applied behavior analysis》2011,44(3):435-450

College students in a psychology research-methods course learned concepts related to inferential statistics and hypothesis decision making. One group received equivalence-based instruction on conditional discriminations that were expected to promote the emergence of many untaught, academically useful abilities (i.e., stimulus equivalence group). A negative control group received no instruction, and a positive (complete instruction) control group received instruction on all possible relations (those taught to, and emerging untaught in, the stimulus equivalence group). On posttests, the stimulus equivalence group performed as well as the positive control group (and both outperformed the negative control group), but those in the equivalence-based instruction condition achieved this outcome with significantly less training, thereby demonstrating the efficiency of equivalence-based instruction. Social validity measures indicated that participants found the instruction to be beneficial and as enjoyable as traditional teaching methods.  相似文献   

    

Urcuioli PJ  Vasconcelos M 《Journal of the experimental analysis of behavior》2008,90(1):61-80

Two experiments evaluated the source(s) of emergent differential sample behavior in pigeons. Initially, pigeons learned two-sample, two-alternative symbolic matching in which different patterns of sample responding were required to produce the comparisons. Afterwards, two other samples nominally identical to the comparisons were added to the matching task. On new-sample trials, completion of either sample-response requirement produced comparison alternatives which were either the same as or different from the alternatives on the familiar-sample trials. Differential responding to the new samples developed only when the comparisons were the same as the familiar samples. The results are consistent with acquired sample equivalence and adventitious reinforcement accounts of emergent sample behavior and are inconsistent with bidirectional transfer (symmetry) between the response patterns explicitly required to the originally trained (familiar) samples and the subsequently reinforced comparisons.  相似文献   

  总被引：6，自引：6，他引：0  

Dugdale N  Lowe CF 《Journal of the experimental analysis of behavior》2000,73(1):5-22

If subjects are taught to match Stimulus A to B and then, without further training, match B to A, they have passed a test of symmetry. It has been suggested that non-humans' lack of success on symmetry tests might be overcome by giving them a history of symmetry exemplar training, that is, by directly teaching a large number of conditional relations (e.g., AB, CD, EF,...) and also directly training the \"reverse\" of these relations (e.g., BA, DC, FE,...). The chimpanzee subjects of the present study, Sherman, Austin, and Lana, had already received extensive symmetry exemplar training as a result of attempts to teach a selection-based language system of lexigrams. The present study systematically subjected 2 of these chimps (Sherman and Lana), for the first time, to standard symmetry tests in controlled conditions. Both chimps failed the tests, even when their correct responses on test trials were reinforced. The findings do not support the exemplar training hypothesis, and cast doubt upon whether the chimps can pass tests of stimulus equivalence.  相似文献