Visual working memory contaminates perception

Indirect evidence suggests that the contents of visual working memory may be maintained within sensory areas early in the visual hierarchy. We tested this possibility using a well-studied motion repulsion phenomenon in which perception of one direction of motion is distorted when another direction of motion is viewed simultaneously. We found that observers misperceived the actual direction of motion of a single motion stimulus if, while viewing that stimulus, they were holding a different motion direction in visual working memory. Control experiments showed that none of a variety of alternative explanations could account for this repulsion effect induced by working memory. Our findings provide compelling evidence that visual working memory representations directly interact with the same neural mechanisms as those involved in processing basic sensory events.     

Resistance to change and preference for variable versus fixed response sequences

In Experiment 1, 4 pigeons were trained on a multiple chain schedule in which the initial link was a variable-interval (VI) 20-s schedule signalled by a red or green center key, and terminal links required four responses made to the left (L) and/or right (R) keys. In the REPEAT component, signalled by red keylights, only LRLR terminal-link response sequences were reinforced, while in the VARY component, signalled by green keylights, terminal-link response sequences were reinforced if they satisfied a variability criterion. The reinforcer rate for both components was equated by adjusting the reinforcer probability for correct REPEAT sequences across sessions. Results showed that initial- and terminal-link responding in the VARY component was generally more resistant to prefeeding, extinction, and response-independent food than responding in the REPEAT component. In Experiment 2, the REPEAT and VARY contingencies were arranged as terminal links of a concurrent chain and the relative reinforcer rate was manipulated across conditions. For all pigeons, initial-link response allocation was biased toward the alternative associated with the VARY terminal link. These results replicate previous reports that operant variation is more resistant to change than operant repetition (Doughty & Lattal, 2001), and show that variation is preferred to repetition with reinforcer-related variables controlled. Behavioral momentum theory (Nevin & Grace, 2000) predicts the covariation of preference and resistance to change in Experiments 1 and 2, but does not explain why these aspects of behavior should depend on contingencies that require repetition or variation.     

The use of Internet technology for psychoeducation and support with dementia caregivers

A large randomized trial evaluated the benefits of online education, support, and self-care promotion for caregivers of persons with dementia. Anecdotal reports from participants indicated enjoyment of the materials, convenient access from home, and support from professionals and other caregivers. A substantial number of screened caregivers experienced obstacles of access, cost, and time regarding use of technology. Telephone options are being explored, and future caregiving generations are expected to have increased exposure and willingness to use computer technology, such as the program described here.     

Is “Σ” purple or green? Bistable grapheme-color synesthesia induced by ambiguous characters

People with grapheme-color synesthesia perceive specific colors when viewing different letters or numbers. Previous studies have suggested that synesthetic color experience can be bistable when induced by an ambiguous character. However, the exact relationship between processes underlying the identity of an alphanumeric character and the experience of the induced synesthetic color has not been examined. In the present study, we explored this by focusing on the temporal relation of inducer identification and color emergence using inducers whose identity could be rendered ambiguous upon rotation of the characters. Specifically, achromatic alphabetic letters (W/M) and digits (6/9) were presented at varying angles to 9 grapheme-color synesthetes. Results showed that grapheme identification and synesthetically perceived grapheme color covary with the orientation of the test stimulus and that synesthetes were slower naming the experienced color than identifying the character, particularly at intermediate angles where ambiguity was greatest.     

Influence of Cognitive Factors on Sexual Assault Recovery: Descriptive Review and Methodological Concerns

This article aims to verify whether the empirical data presented in the literature on sexually assaulted victims support the hypothesis advanced by various aetiological models, which is that cognitions play an important role in the development and maintenance of Post-Traumatic Stress Disorder. The first objective is to present state-of-the-art results on sexually assaulted victims' post-traumatic cognitions and their link to post-assault symptomatology. The second objective is to analyse the various methodological facets of those studies. Finally, paths for future studies are traced and recommendations are made.     

The “Mind's Eye” and Metered-Memory Search

The effects of imagery value of noun stimuli were investigated in a metered-memory search paradigm. A within-subjects design was used with two levels of imagery (high or low) and three transformation levels. Response latency increased significantly with transformation level and was significantly faster when high-imagery nouns composed the memory set. The imagery effect was not found to lead to differential search rates. The hypothesis that metered-memory search would include a component of visually regenerating the memory set and holding it for the actual search was supported. No evidence was found against the notion that the search itself was verbal in nature.     

Interactive effects of proactive personality and display rules on emotional labor in organizations

Emotional labor is the management of emotional displays that happens in the context of a work role. Past research has shown that organizational display rules (standards for emotions that should be shown and hidden from customers) influence emotional labor, but little research has examined the individual differences that make employees more or less responsive to these display rules. The present study draws on concepts from the control theory model of emotional labor to address this limitation by examining the moderating role of proactive personality. Results indicate that proactive individuals are highly responsive to different types of display rules that prompt the use of different emotional labor strategies, highlighting the importance of how display expectations are framed for employees.     

Independence of terminal-link entry rate and immediacy in concurrent chains

In Phase 1, 4 pigeons were trained on a three-component multiple concurrent-chains procedure in which components differed only in terms of relative terminal-link entry rate. The terminal links were variable-interval schedules and were varied across four conditions to produce immediacy ratios of 4:1, 1:4, 2:1, and 1:2. Relative terminal-link entry rate and relative immediacy had additive and independent effects on initial-link response allocation, and the data were well-described by a generalized-matching model. Regression analyses showed that allowing sensitivity to immediacy to vary across components produced only trivial increases in variance accounted for. Phase 2 used a three-component concurrent-schedules procedure in which the schedules were the same as the initial links of Phase 1. Across two conditions, the relative reinforcer magnitude was varied. Sensitivity to relative reinforcer rate was independent of relative magnitude, confirming results of prior studies. Sensitivity to relative reinforcer rate in Phase 2 did not vary systematically across subjects compared to sensitivity to relative entry rate in Phase 1, and regression analyses confirmed again that only small increases in variance accounted for were obtained when sensitivities were estimated independently compared with a single estimate for both phases. Overall, the data suggest that conditioned and primary reinforcers have functionally equivalent effects on choice and support the independence of relative terminal-link entry rate and immediacy as determiners of response allocation. These results are consistent with current models for concurrent chains, including Grace's (1994) contextual choice model and Mazur's (2001) hyperbolic value-added model.