The role of stimulus ambiguity and movement in spatial navigation: a multiple memory systems analysis of location discrimination

This paper reviews recent findings about how rats navigate by learning to discriminate among locations. The assumption underlying the experiments and their interpretation is that the information required to do this is learned by three independent, parallel memory systems. One system processes cognitive information (or "knowledge"), a second system processes reinforced stimulus-response associations and a third processes Pavlovian conditioned responses in the form of stimulus-affect associations. The information stored in each system produces behavior that, in some cases, results in a location discrimination. The present experiments focus on three factors that influence what each system learns and whether the resulting memory produces behavior that results in a location discrimination. One factor is whether the locations to be discriminated can be identified by unique, unambiguous stimuli or whether they are ambiguously associated with the same stimuli. The second factor is whether the stimuli are observed passively or whether the rats move among them, voluntarily or involuntarily. The third factor is whether or not the rats perform specific reinforced responses in the presence of the stimuli. Instances of co-operative behavioral outputs from memory systems that facilitate location discriminations and of competitive outputs that impede discriminations are described.     

Methodological issues in judgment and decision-making research: Concurrent verbal protocol validity and simultaneous traces of process

This paper examines two dimensions of concurrent verbal protocol validity. First, whether verbalization affects process and outcome (reactivity) was examined by comparing concurrent verbal protocol traces with those from a computer search process tracing method, the latter being a complete trace of information acquisition from experimental materials. Earlier findings that verbalization affects time were confirmed. However, verbalization did not affect amount and pattern of acquisition or accuracy of judgments. Second, whether concurrent verbal protocols are complete was examined by comparing concurrent verbal protocol and computer traces that were simultaneously obtained in a treatment in which subjects verbalized as they acquired information from the computer. The verbal traces less completely captured information acquisition behavior than computer search. This suggests that, although concurrent verbal protocols provide greater insight into decision behavior than computer search, the latter is a more reliable information-acquisition trace. Thus, if information acquisition is of primary interest and if computer search activities can be naturally integrated into performing the primary task, computer search is preferred to concurrent verbal protocols. However, if information use or retrieval from long-term memory is of primary interest, concurrent verbal protocols are preferred to computer search. Finally, this paper examined whether the simultaneous use of concurrent verbal protocols and computer search provides traces of information acquisition and use that are as complete as when each method is independently applied. Although computer search tended to limit subjects verbalizations of evaluative operators, this effect may be eliminated by practice on the computer prior to collecting data.     

Five Phases of Dyadic Analysis: Stretching the Boundaries of Understanding of Family Relationships

In the last decade, an increasing number of qualitative studies sought to investigate the dynamics of various dyads by conducting in-depth, multiple family member interviews. The emphasis in the methodological literature dealing with this type of research is primarily on the data collection process, and much less on the development of methods suitable for the analysis of the data thus derived, especially with regard to dyads consisting of family members belonging to different systems: families of origin or nuclear families. The purpose of this paper is to propose a model for dyadic analysis based on examining the dynamics of the evolving relationships between key caregivers of a family member with brain injury. The model includes inductive and abductive phases of analysis, and it is based on an ecological-systemic perspective. The benefits of this model are highlighted, and its potential contribution is further discussed.     

Identification accuracy of a single culprit in a multiple-perpetrator mock crime

IntroductionEyewitness identification research has mainly examined the identification accuracy of a single perpetrator but many actual crimes involve not one but several perpetrators.ObjectiveThe aim of the study was to examine the identification accuracy if only one lineup for one of the two perpetrators is presented in a multiple perpetrator crime.MethodThe sample consisted of 180 participants who saw a theft video followed by distraction tasks. One group of participants saw lineups for both of the perpetrators (one target present and one target-absent) whereas the other saw only a single lineup (either target-present or target-absent) for one of the two perpetrators.ResultsParticipants who saw a single lineup did not make more inaccurate identification decisions then participants who saw two lineups. Decision accuracy in the first lineup was not associated with the decision accuracy in the second lineup.ConclusionThe results are discussed in terms of the number of perpetrators and line-up presentation types.     

The Complex Interplay Between Trait Fatigue and Cognition in Multiple Sclerosis

Cognitive impairments are frequent in patients with Multiple Sclerosis (MS). Yet, the influence of MS-related symptoms on cognitive status is not clear. Studies investigating the impact of trait fatigue along with anxio-depressive symptoms on cognition are seldom, and even less considered fatigue as multidimensional. Moreover, these studies provided conflicting results.Twenty-nine MS patients and 28 healthy controls, matched on age, gender and education underwent a full comprehensive neuropsychological assessment. Anxio-depressive and fatigue symptoms were assessed using the HAD scale and the MFIS, respectively. Six composite scores were derived from the neuropsychological assessment, reflecting the cognitive domains of working memory, verbal and visual learning, executive functions, attention and processing speed. Stepwise regression analyses were conducted in each group to investigate if trait cognitive and physical fatigue, depression and anxiety are relevant predictors of performance in each cognitive domain. In order to control for disease progression, patient’s EDSS score was also entered as predictor variable.In the MS group, trait physical fatigue was the only significant predictor of working memory score. Cognitive fatigue was a predictor for executive functioning performance and for processing speed (as well as EDSS score for processing speed). In the healthy controls group, only an association between executive functioning and depression was observed.Fatigue predicted cognition in MS patients only, beyond anxio-depressive symptoms and disease progression. Considering fatigue as a multidimensional symptom is paramount to better understand its association with cognition, as physical and cognitive fatigue are predictors of different cognitive processes.     

Is motion extrapolation employed in multiple object tracking? Tracking as a low-level, non-predictive function

In a series of five experiments, we investigated whether visual tracking mechanisms utilize prediction when recovering multiple reappearing objects. When all objects abruptly disappeared and reappeared mid-trajectory, it was found that (a) subjects tracked better when objects reappeared at their loci of disappearance than when they reappeared in their extrapolated trajectories, (b) disappearance episodes ranging from 150 to 900 ms had virtually no differential effect on performance, (c) tracking deteriorated monotonically as a function of displacement magnitude during disappearance, and (d) tracking did not depend on whether objects moved in predictable paths. Even objects that reappeared backward in their trajectories were tracked dramatically better than objects that reappeared in their extrapolated trajectories. When all objects disappeared and reappeared in ways that implicated the presence of an occluder (i.e., with occlusion and disocclusion cues along fixed contours), tracking again was not predictive, and performance deteriorated with increased displacement. When objects reappeared predictably in 75% of trials, they were still tracked better when they reappeared at their points of disappearance. Theoretical implications of a non-predictive multiple object tracking mechanism are discussed.     

成就动机的多重目标理论

基于成就目标的三分法,Harackiewicz等人提出多重目标理论。该理论认为,学生在学习过程中采用多种类型的成就目标将会带来最佳的适应性结果,这种观点与单纯强调掌握目标正性作用的传统目标理论相对立。根据多重目标对成就结果的作用模式,理论学家分别提出了四种模型：累加目标模型、交互目标模型、特定目标模型以及选择目标模型。最近的实证研究支持了选择目标模型的观点,并为如何提升个体的成就水平提供了重要的理论依据。     

Promoting Generalization of Oral Reading Fluency: Providing Drill versus Practice Opportunities

Extensive evidence exists demonstrating the benefits of repeated readings (RR) interventions at increasing students’ fluency on intervention passages. Few studies however have examined the extent to which repeatedly reading one passage improves students’ reading fluency on similar passages. Using an alternating treatment design, we examined the extent to which two interventions resulted in improvements in students’ fluency on generalization passages. While both interventions incorporated RR, one intervention involved students reading one passage four times and the other involved students reading two similar passages each twice. Intervention effects were evaluated by having students read a generalization passage prior to and following intervention implementation. Results indicate that both interventions were effective in increasing students reading fluency on generalization passages. For 3 participants the RR intervention produced greater gains in fluency on the generalization passages, while data for the remaining 3 participants are inconclusive. Implications of these findings for practice and for better understanding application of the instructional hierarchy to the development of reading interventions are discussed.

Memory transfer for emotionally valenced words between identities in dissociative identity disorder

The present study aimed to determine interidentity retrieval of emotionally valenced words in dissociative identity disorder (DID). Twenty-two DID patients participated together with 25 normal controls and 25 controls instructed to simulate DID. Two wordlists A and B were constructed including neutral, positive and negative material. List A was shown to one identity, while list B was shown to another identity claiming total amnesia for the words learned by the first identity. The identity claiming amnesia was tested for intrusions from list A words into the recall of words from list B and recognition of the words learned by both identities. Test results indicated no evidence of total interidentity amnesia for emotionally valenced material in DID. It is argued that dissociative amnesia in DID may more adequately be described as a disturbance in meta-memory functioning instead of an actual retrieval inability.     

Perfectionism and exam performance: The mediating effect of task-approach goals

Perfectionistic strivings are positively correlated with students’ achievement goals and exam performance. However, so far no study has employed a prospective design investigating whether achievement goals mediate the positive relationship between perfectionistic strivings and exam performance. In the present study, 100 university students completed a measure of self-oriented perfectionism and socially prescribed perfectionism (Hewitt & Flett, 1991) and received a chapter from a textbook to study for 2–4 days. Then they returned to the lab to complete a measure of achievement goals following the 3 × 2 model (Elliot, Murayama, & Pekrun, 2011) and sit a mock exam testing their knowledge of the chapter. Multiple regressions showed that socially prescribed perfectionism negatively predicted exam performance when the overlap with self-oriented perfectionism was controlled for. In contrast, self-oriented perfectionism—a defining indicator of perfectionistic strivings—positively predicted exam performance. Moreover, task-approach goals mediated the positive relationship between self-oriented perfectionism and exam performance. The findings suggest that perfectionistic strivings make students adopt task-approach goals that help them achieve better results on exams.