Organizational factors and mental health in community volunteers. The role of exposure,preparation, training,tasks assigned,and support

During disasters, aid organizations often respond using the resources of local volunteer members from the affected population who are not only inexperienced, but who additionally take on some of the more psychologically and physically difficult tasks in order to provide support for their community. Although not much empirical evidence exists to justify the claim, it is thought that preparation, training, and organizational support limit (or reduce) a volunteer's risk of developing later psychopathology. In this study, we examined the effects of preparation, training, and organizational support and assigned tasks on the mental health of 506 Indonesian Red Cross volunteers who participated in the response to a massive earthquake in Yogyakarta, Indonesia, in 2006. Controlling for exposure level, the volunteers were assessed for post-traumatic stress disorder (PTSD), anxiety, depression, and subjective health complaints (SHCs) 6, 12, and 18 months post-disaster. Results showed high levels of PTSD and SHCs up to 18 months post-disaster, while anxiety and depression levels remained in the normal range. Higher levels of exposure as well as certain tasks (e.g., provision of psychosocial support to beneficiaries, handling administration, or handing out food aid) made the volunteers more vulnerable. Sense of safety, expressed general need for support at 6 months, and a lack of perceived support from team leaders and the organization were also related to greater psychopathology at 18 months. The results highlight the importance of studying organizational factors. By incorporating these results into future volunteer management programs the negative effects of disaster work on volunteers can be ameliorated.     

Retrieval experience as a modifier of future encoding: another test effect

Research on how individuals monitor their level of comprehension during study paints a picture of learners as being insensitive to many of the factors or conditions of learning that can enhance long-term retention and transfer. In previous research, however, deWinstanley and Bjork (2004) demonstrated that learners--if made sensitive to the memorial benefits of generation in the context of an informative test following study of a text passage in which they had encoded both to-be-read and to-be-generated critical items--then became more effective processors of future to-be-read information presented in a 2nd text passage. In Experiments 1 and 2 of the present research, we explored the potential applicability of this effect by testing whether it could survive certain types of activity-filled delays. In Experiments 3 and 4, we tested whether enhanced processing of contextual information, an encoding strategy that could possibly have been discovered by participants during the testing episode for the 1st text passage, was a potential underlying cause of this effect. Together, our results bring to light an additional benefit of test taking and point to what might be considered necessary and sufficient conditions for leading learners to become more effective processors of future to-be-learned information.     

The costs and benefits of testing text materials

Tests have been shown to improve the later recall of tested information, a result known as the testing effect. Tests, however, can also impair the later recall of related information, an effect known as retrieval-induced forgetting. Although retrieval-induced forgetting has been demonstrated using a wide variety of materials, recent work suggests that learning information in the context of a coherent text passage may afford protection from retrieval-induced forgetting. In four experiments we explored the conditions under which retrieval-induced forgetting does and does not occur with such materials. We found that two factors-the coherence of the to-be-learned material and the competitiveness of retrieval practice-are important in determining whether retrieval-induced forgetting does or does not occur. Furthermore, even if retrieval-induced forgetting does occur, having the opportunity to restudy the forgotten information can prevent that forgetting from persisting. Taken together, these findings provide greater understanding of the costs and benefits of testing text materials, with possible implications for the optimisation of testing as a tool for learning in educational contexts.     

The stimulus prefix is not irrelevant and is redundant in different ways

The present study examined the stimulus prefix effect of immediate recall under conditions in which the prefix element was defined explicitly as being an irrelevant item that should be ignored, or, alternatively, as an item to be remembered and recalled. Memory was poorer in the latter case. Also examined were the effects of three types of redundancy relation between the prefix and target elements; one of these, interstring redundancy (same prefix precedes each target string), was found to improve recall in a relative sense, and another, conceptual redundancy (prefix and target items belong to the same conceptual category), was found to degrade it. Thus, that part of the conventional stimulus prefix effect attributable to redundancy, per se, can be viewed as a composite of at least two opposing factors. Finally, the independent variables of the present study were interpreted to impose different information-processing requirements on the subject, and an account of these requirements was offered.     

Infant search errors: Stage of concept development or stage of memory development

Memory & Cognition - An 8-to-12-month-old infant, having found an object hidden at a first location (A), will frequently continue to search at the A location when the object is moved, in full...     

Letter identification in relation to linguistic context and masking conditions

With a two-choice detection procedure, identifiability of signal letters was determined in backgrounds of words, nonword letter strings, or homogeneous noise characters. Under high performance conditions of exposure duration and pre- and postmasks, there was a substantial advantage in identifiability of letters presented alone over letters embedded in words; under low performance conditions there were generally no differences between the two types of context, but some interactive effects appeared involving particular letters with serial position and type of background. No differences were obtained between word and nonword contexts. The disparities between these findings and those reported by Reicher (1969) and Wheeler (1970) may be related to the more complete elimination under the present procedures of effects of redundancy on response selection.     

Detection and placement of redundant signal elements in tachistoscopic displays of letters

On each trial of a forced-choice detection experiment, S indicated which of two signal elements was represented and also specified the cell of the 5 by 5 matrix display in which he detected the signal. Reaction time on correct choice, Correct placement trials proved virtually invariant with respect to number of redundant signal elements present in the display. These data do not support a serial model for sensory processing, but they could be accommodated by a parallel model for sensory processing together with a serial self-terminating model for processes involving comparison of elements of a display with items in memory. Further analyses of both frequency and reaction time data support the assumption that the distributions of observed detection response measures represent mixtures of true detections, guesses, and misperceptions.     

Retrieval-induced forgetting in an eyewitness-memory paradigm

The potential impact of repeated questioning of a witness was examined. Subjects were shown slides depicting the aftermath of a theft and subsequently were asked several times to recall selected details of what they saw. Previous experiments employing simple verbal materials have demonstrated that information addressed by questioning becomes more recallable in the future than it would have been without such retrieval practice, but other information, especially that bearing a categorical similarity to the practiced items, becomes less recallable. Such positive and negative effects appeared in subjects’ later recall of crime-scene details in the present experiment. These results have an important implication for legal practice: Repeated interrogation of a witness can modify the witness’s memory-enhancing the recall of certain details while inducing the forgetting of other details-even when no misinformation is contained or implied in the questioning.